summaryrefslogtreecommitdiff
path: root/mm/page_alloc.c
AgeCommit message (Collapse)Author
2018-10-09mm, sched/numa: Remove remaining traces of NUMA rate-limitingSrikar Dronamraju
Remove the leftover pglist_data::numabalancing_migrate_lock and its initialization, we stopped using this lock with: efaffc5e40ae ("mm, sched/numa: Remove rate-limiting of automatic NUMA balancing migration") [ mingo: Rewrote the changelog. ] Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linux-MM <linux-mm@kvack.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1538824999-31230-1-git-send-email-srikar@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-02mm, sched/numa: Remove rate-limiting of automatic NUMA balancing migrationMel Gorman
Rate limiting of page migrations due to automatic NUMA balancing was introduced to mitigate the worst-case scenario of migrating at high frequency due to false sharing or slowly ping-ponging between nodes. Since then, a lot of effort was spent on correctly identifying these pages and avoiding unnecessary migrations and the safety net may no longer be required. Jirka Hladky reported a regression in 4.17 due to a scheduler patch that avoids spreading STREAM tasks wide prematurely. However, once the task was properly placed, it delayed migrating the memory due to rate limiting. Increasing the limit fixed the problem for him. Currently, the limit is hard-coded and does not account for the real capabilities of the hardware. Even if an estimate was attempted, it would not properly account for the number of memory controllers and it could not account for the amount of bandwidth used for normal accesses. Rather than fudging, this patch simply eliminates the rate limiting. However, Jirka reports that a STREAM configuration using multiple processes achieved similar performance to 4.16. In local tests, this patch improved performance of STREAM relative to the baseline but it is somewhat machine-dependent. Most workloads show little or not performance difference implying that there is not a heavily reliance on the throttling mechanism and it is safe to remove. STREAM on 2-socket machine 4.19.0-rc5 4.19.0-rc5 numab-v1r1 noratelimit-v1r1 MB/sec copy 43298.52 ( 0.00%) 44673.38 ( 3.18%) MB/sec scale 30115.06 ( 0.00%) 31293.06 ( 3.91%) MB/sec add 32825.12 ( 0.00%) 34883.62 ( 6.27%) MB/sec triad 32549.52 ( 0.00%) 34906.60 ( 7.24% Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Reviewed-by: Rik van Riel <riel@surriel.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Jirka Hladky <jhladky@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linux-MM <linux-mm@kvack.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20181001100525.29789-2-mgorman@techsingularity.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-04mm/hugetlb: filter out hugetlb pages if HUGEPAGE migration is not supported.Aneesh Kumar K.V
When scanning for movable pages, filter out Hugetlb pages if hugepage migration is not supported. Without this we hit infinte loop in __offline_pages() where we do pfn = scan_movable_pages(start_pfn, end_pfn); if (pfn) { /* We have movable pages */ ret = do_migrate_range(pfn, end_pfn); goto repeat; } Fix this by checking hugepage_migration_supported both in has_unmovable_pages which is the primary backoff mechanism for page offlining and for consistency reasons also into scan_movable_pages because it doesn't make any sense to return a pfn to non-migrateable huge page. This issue was revealed by, but not caused by 72b39cfc4d75 ("mm, memory_hotplug: do not fail offlining too early"). Link: http://lkml.kernel.org/r/20180824063314.21981-1-aneesh.kumar@linux.ibm.com Fixes: 72b39cfc4d75 ("mm, memory_hotplug: do not fail offlining too early") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reported-by: Haren Myneni <haren@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-30notifier: Remove notifier header file wherever not usedMukesh Ojha
The conversion of the hotplug notifiers to a state machine left the notifier.h includes around in some places. Remove them. Signed-off-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/1535114033-4605-1-git-send-email-mojha@codeaurora.org
2018-08-23mm: soft-offline: close the race against page allocationNaoya Horiguchi
A process can be killed with SIGBUS(BUS_MCEERR_AR) when it tries to allocate a page that was just freed on the way of soft-offline. This is undesirable because soft-offline (which is about corrected error) is less aggressive than hard-offline (which is about uncorrected error), and we can make soft-offline fail and keep using the page for good reason like "system is busy." Two main changes of this patch are: - setting migrate type of the target page to MIGRATE_ISOLATE. As done in free_unref_page_commit(), this makes kernel bypass pcplist when freeing the page. So we can assume that the page is in freelist just after put_page() returns, - setting PG_hwpoison on free page under zone->lock which protects freelists, so this allows us to avoid setting PG_hwpoison on a page that is decided to be allocated soon. [akpm@linux-foundation.org: tweak set_hwpoison_free_buddy_page() comment] Link: http://lkml.kernel.org/r/1531452366-11661-3-git-send-email-n-horiguchi@ah.jp.nec.com Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reported-by: Xishi Qiu <xishi.qiuxishi@alibaba-inc.com> Tested-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: <zy.zhengyi@alibaba-inc.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22mm/page_alloc: Introduce free_area_init_core_hotplugOscar Salvador
Currently, whenever a new node is created/re-used from the memhotplug path, we call free_area_init_node()->free_area_init_core(). But there is some code that we do not really need to run when we are coming from such path. free_area_init_core() performs the following actions: 1) Initializes pgdat internals, such as spinlock, waitqueues and more. 2) Account # nr_all_pages and # nr_kernel_pages. These values are used later on when creating hash tables. 3) Account number of managed_pages per zone, substracting dma_reserved and memmap pages. 4) Initializes some fields of the zone structure data 5) Calls init_currently_empty_zone to initialize all the freelists 6) Calls memmap_init to initialize all pages belonging to certain zone When called from memhotplug path, free_area_init_core() only performs actions #1 and #4. Action #2 is pointless as the zones do not have any pages since either the node was freed, or we are re-using it, eitherway all zones belonging to this node should have 0 pages. For the same reason, action #3 results always in manages_pages being 0. Action #5 and #6 are performed later on when onlining the pages: online_pages()->move_pfn_range_to_zone()->init_currently_empty_zone() online_pages()->move_pfn_range_to_zone()->memmap_init_zone() This patch does two things: First, moves the node/zone initializtion to their own function, so it allows us to create a small version of free_area_init_core, where we only perform: 1) Initialization of pgdat internals, such as spinlock, waitqueues and more 4) Initialization of some fields of the zone structure data These two functions are: pgdat_init_internals() and zone_init_internals(). The second thing this patch does, is to introduce free_area_init_core_hotplug(), the memhotplug version of free_area_init_core(): Currently, we call free_area_init_node() from the memhotplug path. In there, we set some pgdat's fields, and call calculate_node_totalpages(). calculate_node_totalpages() calculates the # of pages the node has. Since the node is either new, or we are re-using it, the zones belonging to this node should not have any pages, so there is no point to calculate this now. Actually, we re-set these values to 0 later on with the calls to: reset_node_managed_pages() reset_node_present_pages() The # of pages per node and the # of pages per zone will be calculated when onlining the pages: online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_zone_range() online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_pgdat_range() Also, since free_area_init_core/free_area_init_node will now only get called during early init, let us replace __paginginit with __init, so their code gets freed up. [osalvador@techadventures.net: fix section usage] Link: http://lkml.kernel.org/r/20180731101752.GA473@techadventures.net [osalvador@suse.de: v6] Link: http://lkml.kernel.org/r/20180801122348.21588-6-osalvador@techadventures.net Link: http://lkml.kernel.org/r/20180730101757.28058-5-osalvador@techadventures.net Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22mm/page_alloc: inline function to handle CONFIG_DEFERRED_STRUCT_PAGE_INITOscar Salvador
Let us move the code between CONFIG_DEFERRED_STRUCT_PAGE_INIT to an inline function. Not having an ifdef in the function makes the code more readable. Link: http://lkml.kernel.org/r/20180730101757.28058-4-osalvador@techadventures.net Signed-off-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22mm: remove __paginginitPavel Tatashin
__paginginit is the same thing as __meminit except for platforms without sparsemem, there it is defined as __init. Remove __paginginit and use __meminit. Use __ref in one single function that merges __meminit and __init sections: setup_usemap(). Link: http://lkml.kernel.org/r/20180801122348.21588-4-osalvador@techadventures.net Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22mm: access zone->node via zone_to_nid() and zone_set_nid()Pavel Tatashin
zone->node is configured only when CONFIG_NUMA=y, so it is a good idea to have inline functions to access this field in order to avoid ifdef's in c files. Link: http://lkml.kernel.org/r/20180730101757.28058-3-osalvador@techadventures.net Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22mm/page_alloc.c: move ifdefery out of free_area_init_coreOscar Salvador
Patch series "Refactor free_area_init_core and add free_area_init_core_hotplug", v6. This patchset does three things: 1) Clean up/refactor free_area_init_core/free_area_init_node by moving the ifdefery out of the functions. 2) Move the pgdat/zone initialization in free_area_init_core to its own function. 3) Introduce free_area_init_core_hotplug, a small subset of free_area_init_core, which is only called from memhotlug code path. In this way, we have: free_area_init_core: called during early initialization free_area_init_core_hotplug: called whenever a new node is allocated/re-used (memhotplug path) This patch (of 5): Moving the #ifdefs out of the function makes it easier to follow. Link: http://lkml.kernel.org/r/20180730101757.28058-2-osalvador@techadventures.net Signed-off-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17mm, page_alloc: double zone's batchsizeAaron Lu
To improve page allocator's performance for order-0 pages, each CPU has a Per-CPU-Pageset(PCP) per zone. Whenever an order-0 page is needed, PCP will be checked first before asking pages from Buddy. When PCP is used up, a batch of pages will be fetched from Buddy to improve performance and the size of batch can affect performance. zone's batch size gets doubled last time by commit ba56e91c9401("mm: page_alloc: increase size of per-cpu-pages") over ten years ago. Since then, CPU has envolved a lot and CPU's cache sizes also increased. Dave Hansen is concerned the current batch size doesn't fit well with modern hardware and suggested me to do two things: first, use a page allocator intensive benchmark, e.g. will-it-scale/page_fault1 to find out how performance changes with different batch sizes on various machines and then choose a new default batch size; second, see how this new batch size work with other workloads. In the first test, we saw performance gains on high-core-count systems and little to no effect on older systems with more modest core counts. In this phase's test data, two candidates: 63 and 127 are chosen. In the second step, ebizzy, oltp, kbuild, pigz, netperf, vm-scalability and more will-it-scale sub-tests are tested to see how these two candidates work with these workloads and decides a new default according to their results. Most test results are flat. will-it-scale/page_fault2 process mode has 10%-18% performance increase on 4-sockets Skylake and Broadwell. vm-scalability/lru-file-mmap-read has 17%-47% performance increase for 4-sockets servers while for 2-sockets servers, it caused 3%-8% performance drop. Further analysis showed that, with a larger pcp->batch and thus larger pcp->high(the relationship of pcp->high=6 * pcp->batch is maintained in this patch), zone lock contention shifted to LRU add side lock contention and that caused performance drop. This performance drop might be mitigated by others' work on optimizing LRU lock. Another downside of increasing pcp->batch is, when PCP is used up and need to fetch a batch of pages from Buddy, since batch is increased, that time can be longer than before. My understanding is, this doesn't affect slowpath where direct reclaim and compaction dominates. For fastpath, throughput is a win(according to will-it-scale/page_fault1) but worst latency can be larger now. Overall, I think double the batch size from 31 to 63 is relatively safe and provide good performance boost for high-core-count systems. The two phase's test results are listed below(all tests are done with THP disabled). Phase one(will-it-scale/page_fault1) test results: Skylake-EX: increased batch size has a good effect on zone->lock contention, though LRU contention will rise at the same time and limited the final performance increase. batch score change zone_contention lru_contention total_contention 31 15345900 +0.00% 64% 8% 72% 53 17903847 +16.67% 32% 38% 70% 63 17992886 +17.25% 24% 45% 69% 73 18022825 +17.44% 10% 61% 71% 119 18023401 +17.45% 4% 66% 70% 127 18029012 +17.48% 3% 66% 69% 137 18036075 +17.53% 4% 66% 70% 165 18035964 +17.53% 2% 67% 69% 188 18101105 +17.95% 2% 67% 69% 223 18130951 +18.15% 2% 67% 69% 255 18118898 +18.07% 2% 67% 69% 267 18101559 +17.96% 2% 67% 69% 299 18160468 +18.34% 2% 68% 70% 320 18139845 +18.21% 2% 67% 69% 393 18160869 +18.34% 2% 68% 70% 424 18170999 +18.41% 2% 68% 70% 458 18144868 +18.24% 2% 68% 70% 467 18142366 +18.22% 2% 68% 70% 498 18154549 +18.30% 1% 68% 69% 511 18134525 +18.17% 1% 69% 70% Broadwell-EX: similar pattern as Skylake-EX. batch score change zone_contention lru_contention total_contention 31 16703983 +0.00% 67% 7% 74% 53 18195393 +8.93% 43% 28% 71% 63 18288885 +9.49% 38% 33% 71% 73 18344329 +9.82% 35% 37% 72% 119 18535529 +10.96% 24% 46% 70% 127 18513596 +10.83% 23% 48% 71% 137 18514327 +10.84% 23% 48% 71% 165 18511840 +10.82% 22% 49% 71% 188 18593478 +11.31% 17% 53% 70% 223 18601667 +11.36% 17% 52% 69% 255 18774825 +12.40% 12% 58% 70% 267 18754781 +12.28% 9% 60% 69% 299 18892265 +13.10% 7% 63% 70% 320 18873812 +12.99% 8% 62% 70% 393 18891174 +13.09% 6% 64% 70% 424 18975108 +13.60% 6% 64% 70% 458 18932364 +13.34% 8% 62% 70% 467 18960891 +13.51% 5% 65% 70% 498 18944526 +13.41% 5% 64% 69% 511 18960839 +13.51% 5% 64% 69% Skylake-EP: although increased batch reduced zone->lock contention, but the effect is not as good as EX: zone->lock contention is still as high as 20% with a very high batch value instead of 1% on Skylake-EX or 5% on Broadwell-EX. Also, total_contention actually decreased with a higher batch but that doesn't translate to performance increase. batch score change zone_contention lru_contention total_contention 31 9554867 +0.00% 66% 3% 69% 53 9855486 +3.15% 63% 3% 66% 63 9980145 +4.45% 62% 4% 66% 73 10092774 +5.63% 62% 5% 67% 119 10310061 +7.90% 45% 19% 64% 127 10342019 +8.24% 42% 19% 61% 137 10358182 +8.41% 42% 21% 63% 165 10397060 +8.81% 37% 24% 61% 188 10341808 +8.24% 34% 26% 60% 223 10349135 +8.31% 31% 27% 58% 255 10327189 +8.08% 28% 29% 57% 267 10344204 +8.26% 27% 29% 56% 299 10325043 +8.06% 25% 30% 55% 320 10310325 +7.91% 25% 31% 56% 393 10293274 +7.73% 21% 31% 52% 424 10311099 +7.91% 21% 32% 53% 458 10321375 +8.02% 21% 32% 53% 467 10303881 +7.84% 21% 32% 53% 498 10332462 +8.14% 20% 33% 53% 511 10325016 +8.06% 20% 32% 52% Broadwell-EP: zone->lock and lru lock had an agreement to make sure performance doesn't increase and they successfully managed to keep total contention at 70%. batch score change zone_contention lru_contention total_contention 31 10121178 +0.00% 19% 50% 69% 53 10142366 +0.21% 6% 63% 69% 63 10117984 -0.03% 11% 58% 69% 73 10123330 +0.02% 7% 63% 70% 119 10108791 -0.12% 2% 67% 69% 127 10166074 +0.44% 3% 66% 69% 137 10141574 +0.20% 3% 66% 69% 165 10154499 +0.33% 2% 68% 70% 188 10124921 +0.04% 2% 67% 69% 223 10137399 +0.16% 2% 67% 69% 255 10143289 +0.22% 0% 68% 68% 267 10123535 +0.02% 1% 68% 69% 299 10140952 +0.20% 0% 68% 68% 320 10163170 +0.41% 0% 68% 68% 393 10000633 -1.19% 0% 69% 69% 424 10087998 -0.33% 0% 69% 69% 458 10187116 +0.65% 0% 69% 69% 467 10146790 +0.25% 0% 69% 69% 498 10197958 +0.76% 0% 69% 69% 511 10152326 +0.31% 0% 69% 69% Haswell-EP: similar to Broadwell-EP. batch score change zone_contention lru_contention total_contention 31 10442205 +0.00% 14% 48% 62% 53 10442255 +0.00% 5% 57% 62% 63 10452059 +0.09% 6% 57% 63% 73 10482349 +0.38% 5% 59% 64% 119 10454644 +0.12% 3% 60% 63% 127 10431514 -0.10% 3% 59% 62% 137 10423785 -0.18% 3% 60% 63% 165 10481216 +0.37% 2% 61% 63% 188 10448755 +0.06% 2% 61% 63% 223 10467144 +0.24% 2% 61% 63% 255 10480215 +0.36% 2% 61% 63% 267 10484279 +0.40% 2% 61% 63% 299 10466450 +0.23% 2% 61% 63% 320 10452578 +0.10% 2% 61% 63% 393 10499678 +0.55% 1% 62% 63% 424 10481454 +0.38% 1% 62% 63% 458 10473562 +0.30% 1% 62% 63% 467 10484269 +0.40% 0% 62% 62% 498 10505599 +0.61% 0% 62% 62% 511 10483395 +0.39% 0% 62% 62% Westmere-EP: contention is pretty small so not interesting. Note too high a batch value could hurt performance. batch score change zone_contention lru_contention total_contention 31 4831523 +0.00% 2% 3% 5% 53 4834086 +0.05% 2% 4% 6% 63 4834262 +0.06% 2% 3% 5% 73 4832851 +0.03% 2% 4% 6% 119 4830534 -0.02% 1% 3% 4% 127 4827461 -0.08% 1% 4% 5% 137 4827459 -0.08% 1% 3% 4% 165 4820534 -0.23% 0% 4% 4% 188 4817947 -0.28% 0% 3% 3% 223 4809671 -0.45% 0% 3% 3% 255 4802463 -0.60% 0% 4% 4% 267 4801634 -0.62% 0% 3% 3% 299 4798047 -0.69% 0% 3% 3% 320 4793084 -0.80% 0% 3% 3% 393 4785877 -0.94% 0% 3% 3% 424 4782911 -1.01% 0% 3% 3% 458 4779346 -1.08% 0% 3% 3% 467 4780306 -1.06% 0% 3% 3% 498 4780589 -1.05% 0% 3% 3% 511 4773724 -1.20% 0% 3% 3% Skylake-Desktop: similar to Westmere-EP, nothing interesting. batch score change zone_contention lru_contention total_contention 31 3906608 +0.00% 2% 3% 5% 53 3940164 +0.86% 2% 3% 5% 63 3937289 +0.79% 2% 3% 5% 73 3940201 +0.86% 2% 3% 5% 119 3933240 +0.68% 2% 3% 5% 127 3930514 +0.61% 2% 4% 6% 137 3938639 +0.82% 0% 3% 3% 165 3908755 +0.05% 0% 3% 3% 188 3905621 -0.03% 0% 3% 3% 223 3903015 -0.09% 0% 4% 4% 255 3889480 -0.44% 0% 3% 3% 267 3891669 -0.38% 0% 4% 4% 299 3898728 -0.20% 0% 4% 4% 320 3894547 -0.31% 0% 4% 4% 393 3875137 -0.81% 0% 4% 4% 424 3874521 -0.82% 0% 3% 3% 458 3880432 -0.67% 0% 4% 4% 467 3888715 -0.46% 0% 3% 3% 498 3888633 -0.46% 0% 4% 4% 511 3875305 -0.80% 0% 5% 5% Haswell-Desktop: zone->lock is pretty low as other desktops, though lru contention is higher than other desktops. batch score change zone_contention lru_contention total_contention 31 3511158 +0.00% 2% 5% 7% 53 3555445 +1.26% 2% 6% 8% 63 3561082 +1.42% 2% 6% 8% 73 3547218 +1.03% 2% 6% 8% 119 3571319 +1.71% 1% 7% 8% 127 3549375 +1.09% 0% 6% 6% 137 3560233 +1.40% 0% 6% 6% 165 3555176 +1.25% 2% 6% 8% 188 3551501 +1.15% 0% 8% 8% 223 3531462 +0.58% 0% 7% 7% 255 3570400 +1.69% 0% 7% 7% 267 3532235 +0.60% 1% 8% 9% 299 3562326 +1.46% 0% 6% 6% 320 3553569 +1.21% 0% 8% 8% 393 3539519 +0.81% 0% 7% 7% 424 3549271 +1.09% 0% 8% 8% 458 3528885 +0.50% 0% 8% 8% 467 3526554 +0.44% 0% 7% 7% 498 3525302 +0.40% 0% 9% 9% 511 3527556 +0.47% 0% 8% 8% Sandybridge-Desktop: the 0% contention isn't accurate but caused by dropped fractional part. Since multiple contention path's contentions are all under 1% here, with some arithmetic operations like add, the final deviation could be as large as 3%. batch score change zone_contention lru_contention total_contention 31 1744495 +0.00% 0% 0% 0% 53 1755341 +0.62% 0% 0% 0% 63 1758469 +0.80% 0% 0% 0% 73 1759626 +0.87% 0% 0% 0% 119 1770417 +1.49% 0% 0% 0% 127 1768252 +1.36% 0% 0% 0% 137 1767848 +1.34% 0% 0% 0% 165 1765088 +1.18% 0% 0% 0% 188 1766918 +1.29% 0% 0% 0% 223 1767866 +1.34% 0% 0% 0% 255 1768074 +1.35% 0% 0% 0% 267 1763187 +1.07% 0% 0% 0% 299 1765620 +1.21% 0% 0% 0% 320 1767603 +1.32% 0% 0% 0% 393 1764612 +1.15% 0% 0% 0% 424 1758476 +0.80% 0% 0% 0% 458 1758593 +0.81% 0% 0% 0% 467 1757915 +0.77% 0% 0% 0% 498 1753363 +0.51% 0% 0% 0% 511 1755548 +0.63% 0% 0% 0% Phase two test results: Note: all percent change is against base(batch=31). ebizzy.throughput (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 2410037±7% 2600451±2% +7.9% 2602878 +8.0% lkp-bdw-ex1 1493328 1489243 -0.3% 1492145 -0.1% lkp-skl-2sp2 1329674 1345891 +1.2% 1351056 +1.6% lkp-bdw-ep2 711511 711511 0.0% 710708 -0.1% lkp-wsm-ep2 75750 75528 -0.3% 75441 -0.4% lkp-skl-d01 264126 262791 -0.5% 264113 +0.0% lkp-hsw-d01 176601 176328 -0.2% 176368 -0.1% lkp-sb02 98937 98937 +0.0% 99030 +0.1% kbuild.buildtime (less is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 107.00 107.67 +0.6% 107.11 +0.1% lkp-bdw-ex1 97.33 97.33 +0.0% 97.42 +0.1% lkp-skl-2sp2 180.00 179.83 -0.1% 179.83 -0.1% lkp-bdw-ep2 178.17 179.17 +0.6% 177.50 -0.4% lkp-wsm-ep2 737.00 738.00 +0.1% 738.00 +0.1% lkp-skl-d01 642.00 653.00 +1.7% 653.00 +1.7% lkp-hsw-d01 1310.00 1316.00 +0.5% 1311.00 +0.1% netperf/TCP_STREAM.Throughput_total_Mbps (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 948790 947144 -0.2% 948333 -0.0% lkp-bdw-ex1 904224 904366 +0.0% 904926 +0.1% lkp-skl-2sp2 239731 239607 -0.1% 239565 -0.1% lk-bdw-ep2 365764 365933 +0.0% 365951 +0.1% lkp-wsm-ep2 93736 93803 +0.1% 93808 +0.1% lkp-skl-d01 77314 77303 -0.0% 77375 +0.1% lkp-hsw-d01 58617 60387 +3.0% 60208 +2.7% lkp-sb02 29990 30137 +0.5% 30103 +0.4% oltp.transactions (higer is better) machine batch=31 batch=63 batch=127 lkp-bdw-ex1 9073276 9100377 +0.3% 9036344 -0.4% lkp-skl-2sp2 8898717 8852054 -0.5% 8894459 -0.0% lkp-bdw-ep2 13426155 13384654 -0.3% 13333637 -0.7% lkp-hsw-ep2 13146314 13232784 +0.7% 13193163 +0.4% lkp-wsm-ep2 5035355 5019348 -0.3% 5033418 -0.0% lkp-skl-d01 418485 4413339 -0.1% 4419039 +0.0% lkp-hsw-d01 3517817±5% 3396120±3% -3.5% 3455138±3% -1.8% pigz.throughput (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1.513e+08 1.507e+08 -0.4% 1.511e+08 -0.2% lkp-bdw-ex1 2.060e+08 2.052e+08 -0.4% 2.044e+08 -0.8% lkp-skl-2sp2 8.836e+08 8.845e+08 +0.1% 8.836e+08 -0.0% lkp-bdw-ep2 8.275e+08 8.464e+08 +2.3% 8.330e+08 +0.7% lkp-wsm-ep2 2.224e+08 2.221e+08 -0.2% 2.218e+08 -0.3% lkp-skl-d01 1.177e+08 1.177e+08 -0.0% 1.176e+08 -0.1% lkp-hsw-d01 1.154e+08 1.154e+08 +0.1% 1.154e+08 -0.0% lkp-sb02 0.633e+08 0.633e+08 +0.1% 0.633e+08 +0.0% will-it-scale.malloc1.processes (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 620181 620484 +0.0% 620240 +0.0% lkp-bdw-ex1 1403610 1401201 -0.2% 1417900 +1.0% lkp-skl-2sp2 1288097 1284145 -0.3% 1283907 -0.3% lkp-bdw-ep2 1427879 1427675 -0.0% 1428266 +0.0% lkp-hsw-ep2 1362546 1353965 -0.6% 1354759 -0.6% lkp-wsm-ep2 2099657 2107576 +0.4% 2100226 +0.0% lkp-skl-d01 1476835 1476358 -0.0% 1474487 -0.2% lkp-hsw-d01 1308810 1303429 -0.4% 1301299 -0.6% lkp-sb02 589286 589284 -0.0% 588101 -0.2% will-it-scale.malloc1.threads (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 21289 21125 -0.8% 21241 -0.2% lkp-bdw-ex1 28114 28089 -0.1% 28007 -0.4% lkp-skl-2sp2 91866 91946 +0.1% 92723 +0.9% lkp-bdw-ep2 37637 37501 -0.4% 37317 -0.9% lkp-hsw-ep2 43673 43590 -0.2% 43754 +0.2% lkp-wsm-ep2 28577 28298 -1.0% 28545 -0.1% lkp-skl-d01 175277 173343 -1.1% 173082 -1.3% lkp-hsw-d01 130303 129566 -0.6% 129250 -0.8% lkp-sb02 113742±3% 116911 +2.8% 116417±3% +2.4% will-it-scale.malloc2.processes (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1.206e+09 1.206e+09 -0.0% 1.206e+09 +0.0% lkp-bdw-ex1 1.319e+09 1.319e+09 -0.0% 1.319e+09 +0.0% lkp-skl-2sp2 8.000e+08 8.021e+08 +0.3% 7.995e+08 -0.1% lkp-bdw-ep2 6.582e+08 6.634e+08 +0.8% 6.513e+08 -1.1% lkp-hsw-ep2 6.671e+08 6.669e+08 -0.0% 6.665e+08 -0.1% lkp-wsm-ep2 1.805e+08 1.806e+08 +0.0% 1.804e+08 -0.1% lkp-skl-d01 1.611e+08 1.611e+08 -0.0% 1.610e+08 -0.0% lkp-hsw-d01 1.333e+08 1.332e+08 -0.0% 1.332e+08 -0.0% lkp-sb02 82485104 82478206 -0.0% 82473546 -0.0% will-it-scale.malloc2.threads (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1.574e+09 1.574e+09 -0.0% 1.574e+09 -0.0% lkp-bdw-ex1 1.737e+09 1.737e+09 +0.0% 1.737e+09 -0.0% lkp-skl-2sp2 9.161e+08 9.162e+08 +0.0% 9.181e+08 +0.2% lkp-bdw-ep2 7.856e+08 8.015e+08 +2.0% 8.113e+08 +3.3% lkp-hsw-ep2 6.908e+08 6.904e+08 -0.1% 6.907e+08 -0.0% lkp-wsm-ep2 2.409e+08 2.409e+08 +0.0% 2.409e+08 -0.0% lkp-skl-d01 1.199e+08 1.199e+08 -0.0% 1.199e+08 -0.0% lkp-hsw-d01 1.029e+08 1.029e+08 -0.0% 1.029e+08 +0.0% lkp-sb02 68081213 68061423 -0.0% 68076037 -0.0% will-it-scale.page_fault2.processes (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 14509125±4% 16472364 +13.5% 17123117 +18.0% lkp-bdw-ex1 14736381 16196588 +9.9% 16364011 +11.0% lkp-skl-2sp2 6354925 6435444 +1.3% 6436644 +1.3% lkp-bdw-ep2 8749584 8834422 +1.0% 8827179 +0.9% lkp-hsw-ep2 8762591 8845920 +1.0% 8825697 +0.7% lkp-wsm-ep2 3036083 3030428 -0.2% 3021741 -0.5% lkp-skl-d01 2307834 2304731 -0.1% 2286142 -0.9% lkp-hsw-d01 1806237 1800786 -0.3% 1795943 -0.6% lkp-sb02 842616 837844 -0.6% 833921 -1.0% will-it-scale.page_fault2.threads machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1623294 1615132±2% -0.5% 1656777 +2.1% lkp-bdw-ex1 1995714 2025948 +1.5% 2113753±3% +5.9% lkp-skl-2sp2 2346708 2415591 +2.9% 2416919 +3.0% lkp-bdw-ep2 2342564 2344882 +0.1% 2300206 -1.8% lkp-hsw-ep2 1820658 1831681 +0.6% 1844057 +1.3% lkp-wsm-ep2 1725482 1733774 +0.5% 1740517 +0.9% lkp-skl-d01 1832833 1823628 -0.5% 1806489 -1.4% lkp-hsw-d01 1427913 1427287 -0.0% 1420226 -0.5% lkp-sb02 750626 748615 -0.3% 746621 -0.5% will-it-scale.page_fault3.processes (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 24382726 24400317 +0.1% 24668774 +1.2% lkp-bdw-ex1 35399750 35683124 +0.8% 35829492 +1.2% lkp-skl-2sp2 28136820 28068248 -0.2% 28147989 +0.0% lkp-bdw-ep2 37269077 37459490 +0.5% 37373073 +0.3% lkp-hsw-ep2 36224967 36114085 -0.3% 36104908 -0.3% lkp-wsm-ep2 16820457 16911005 +0.5% 16968596 +0.9% lkp-skl-d01 7721138 7725904 +0.1% 7756740 +0.5% lkp-hsw-d01 7611979 7650928 +0.5% 7651323 +0.5% lkp-sb02 3781546 3796502 +0.4% 3796827 +0.4% will-it-scale.page_fault3.threads (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1865820±3% 1900917±2% +1.9% 1826245±4% -2.1% lkp-bdw-ex1 3094060 3148326 +1.8% 3150036 +1.8% lkp-skl-2sp2 3952940 3953898 +0.0% 3989360 +0.9% lkp-bdw-ep2 3420373±3% 3643964 +6.5% 3644910±5% +6.6% lkp-hsw-ep2 2609635±2% 2582310±3% -1.0% 2780459 +6.5% lkp-wsm-ep2 4395001 4417196 +0.5% 4432499 +0.9% lkp-skl-d01 5363977 5400003 +0.7% 5411370 +0.9% lkp-hsw-d01 5274131 5311294 +0.7% 5319359 +0.9% lkp-sb02 2917314 2913004 -0.1% 2935286 +0.6% will-it-scale.read1.processes (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 73762279±14% 69322519±10% -6.0% 69349855±13% -6.0% (result unstable) lkp-bdw-ex1 1.701e+08 1.704e+08 +0.1% 1.705e+08 +0.2% lkp-skl-2sp2 63111570 63113953 +0.0% 63836573 +1.1% lkp-bdw-ep2 79247409 79424610 +0.2% 78012656 -1.6% lkp-hsw-ep2 67677026 68308800 +0.9% 67539106 -0.2% lkp-wsm-ep2 13339630 13939817 +4.5% 13766865 +3.2% lkp-skl-d01 10969487 10972650 +0.0% no data lkp-hsw-d01 9857342±2% 10080592±2% +2.3% 10131560 +2.8% lkp-sb02 5189076 5197473 +0.2% 5163253 -0.5% will-it-scale.read1.threads (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 62468045±12% 73666726±7% +17.9% 79553123±12% +27.4% (result unstable) lkp-bdw-ex1 1.62e+08 1.624e+08 +0.3% 1.614e+08 -0.3% lkp-skl-2sp2 58319780 59181032 +1.5% 59821353 +2.6% lkp-bdw-ep2 74057992 75698171 +2.2% 74990869 +1.3% lkp-hsw-ep2 63672959 63639652 -0.1% 64387051 +1.1% lkp-wsm-ep2 13489943 13526058 +0.3% 13259032 -1.7% lkp-skl-d01 10297906 10338796 +0.4% 10407328 +1.1% lkp-hsw-d01 9636721 9667376 +0.3% 9341147 -3.1% lkp-sb02 4801938 4804496 +0.1% 4802290 +0.0% will-it-scale.write1.processes (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1.111e+08 1.104e+08±2% -0.7% 1.122e+08±2% +1.0% lkp-bdw-ex1 1.392e+08 1.399e+08 +0.5% 1.397e+08 +0.4% lkp-skl-2sp2 59369233 58994841 -0.6% 58715168 -1.1% lkp-bdw-ep2 61820979 CPU throttle 63593123 +2.9% lkp-hsw-ep2 57897587 57435605 -0.8% 56347450 -2.7% lkp-wsm-ep2 7814203 7918017±2% +1.3% 7669068 -1.9% lkp-skl-d01 8886557 8971422 +1.0% 8818366 -0.8% lkp-hsw-d01 9171001±5% 9189915 +0.2% 9483909 +3.4% lkp-sb02 4475406 4475294 -0.0% 4501756 +0.6% will-it-scale.write1.threads (higer is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1.058e+08 1.055e+08±2% -0.2% 1.065e+08 +0.7% lkp-bdw-ex1 1.316e+08 1.300e+08 -1.2% 1.308e+08 -0.6% lkp-skl-2sp2 54492421 56086678 +2.9% 55975657 +2.7% lkp-bdw-ep2 59360449 59003957 -0.6% 58101262 -2.1% lkp-hsw-ep2 53346346±2% 52530876 -1.5% 52902487 -0.8% lkp-wsm-ep2 7774006 7800092±2% +0.3% 7558833 -2.8% lkp-skl-d01 8346174 8235695 -1.3% no data lkp-hsw-d01 8636244 8655731 +0.2% 8658868 +0.3% lkp-sb02 4181820 4204107 +0.5% 4182992 +0.0% vm-scalability.anon-r-rand.throughput (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 11933873±3% 12356544±2% +3.5% 12188624 +2.1% lkp-bdw-ex1 7114424±2% 7330949±2% +3.0% 7392419 +3.9% lkp-skl-2sp2 6773277±5% 6492332±8% -4.1% 6543962 -3.4% lkp-bdw-ep2 7133846±4% 7233508 +1.4% 7013518±3% -1.7% lkp-hsw-ep2 4576626 4527098 -1.1% 4551679 -0.5% lkp-wsm-ep2 2583599 2592492 +0.3% 2588039 +0.2% lkp-hsw-d01 998199±2% 1028311 +3.0% 1006460±2% +0.8% lkp-sb02 570572 567854 -0.5% 568449 -0.4% vm-scalability.anon-r-rand-mt.throughput (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1789419 1787830 -0.1% 1788208 -0.1% lkp-bdw-ex1 3492595±2% 3554966±2% +1.8% 3558835±3% +1.9% lkp-skl-2sp2 3856238±2% 3975403±4% +3.1% 3994600 +3.6% lkp-bdw-ep2 3726963±11% 3809292±6% +2.2% 3871924±4% +3.9% lkp-hsw-ep2 2131760±3% 2033578±4% -4.6% 2130727±6% -0.0% lkp-wsm-ep2 2369731 2368384 -0.1% 2370252 +0.0% lkp-skl-d01 1207128 1206220 -0.1% 1205801 -0.1% lkp-hsw-d01 964317 992329±2% +2.9% 992099±2% +2.9% lkp-sb02 567137 567346 +0.0% 566144 -0.2% vm-scalability.lru-file-mmap-read.throughput (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 19560469±6% 23018999 +17.7% 23418800 +19.7% lkp-bdw-ex1 17769135±14% 26141676±3% +47.1% 26284723±5% +47.9% lkp-skl-2sp2 14056512 13578884 -3.4% 13146214 -6.5% lkp-bdw-ep2 15336542 14737654 -3.9% 14088159 -8.1% lkp-hsw-ep2 16275498 15756296 -3.2% 15018090 -7.7% lkp-wsm-ep2 11272160 11237231 -0.3% 11310047 +0.3% lkp-skl-d01 7322119 7324569 +0.0% 7184148 -1.9% lkp-hsw-d01 6449234 6404542 -0.7% 6356141 -1.4% lkp-sb02 3517943 3520668 +0.1% 3527309 +0.3% vm-scalability.lru-file-mmap-read-rand.throughput (higher is better) machine batch=31 batch=63 batch=127 lkp-skl-4sp1 1689052 1697553 +0.5% 1698726 +0.6% lkp-bdw-ex1 1675246 1699764 +1.5% 1712226 +2.2% lkp-skl-2sp2 1800533 1799749 -0.0% 1800581 +0.0% lkp-bdw-ep2 1807422 1807758 +0.0% 1804932 -0.1% lkp-hsw-ep2 1809807 1808781 -0.1% 1807811 -0.1% lkp-wsm-ep2 1800198 1802434 +0.1% 1801236 +0.1% lkp-skl-d01 696689 695537 -0.2% 694106 -0.4% lkp-hsw-d01 698364 698666 +0.0% 696686 -0.2% lkp-sb02 258939 258787 -0.1% 258199 -0.3% Link: http://lkml.kernel.org/r/20180711055855.29072-1-aaron.lu@intel.com Signed-off-by: Aaron Lu <aaron.lu@intel.com> Suggested-by: Dave Hansen <dave.hansen@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Kemi Wang <kemi.wang@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17mm: drop VM_BUG_ON from __get_free_pagesMichal Hocko
There is no real reason to blow up just because the caller doesn't know that __get_free_pages cannot return highmem pages. Simply fix that up silently. Even if we have some confused users such a fixup will not be harmful. [akpm@linux-foundation.org: mask off __GFP_HIGHMEM] Link: http://lkml.kernel.org/r/20180622162841.25114-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jiankang Chen <chenjiankang1@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Yisheng Xie <xieyisheng1@huawei.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17mm, page_alloc: actually ignore mempolicies for high priority allocationsVlastimil Babka
__alloc_pages_slowpath() has for a long time contained code to ignore node restrictions from memory policies for high priority allocations. The current code that resets the zonelist iterator however does effectively nothing after commit 7810e6781e0f ("mm, page_alloc: do not break __GFP_THISNODE by zonelist reset") removed a buggy zonelist reset. Even before that commit, mempolicy restrictions were still not ignored, as they are passed in ac->nodemask which is untouched by the code. We can either remove the code, or make it work as intended. Since ac->nodemask can be set from task's mempolicy via alloc_pages_current() and thus also alloc_pages(), it may indeed affect kernel allocations, and it makes sense to ignore it to allow progress for high priority allocations. Thus, this patch resets ac->nodemask to NULL in such cases. This assumes all callers can handle it (i.e. there are no guarantees as in the case of __GFP_THISNODE) which seems to be the case. The same assumption is already present in check_retry_cpuset() for some time. The expected effect is that high priority kernel allocations in the context of userspace tasks (e.g. OOM victims) restricted by mempolicies will have higher chance to succeed if they are restricted to nodes with depleted memory, while there are other nodes with free memory left. It's not a new intention, but for the first time the code will match the intention, AFAICS. It was intended by commit 183f6371aac2 ("mm: ignore mempolicies when using ALLOC_NO_WATERMARK") in v3.6 but I think it never really worked, as mempolicy restriction was already encoded in nodemask, not zonelist, at that time. So originally that was for ALLOC_NO_WATERMARK only. Then it was adjusted by e46e7b77c909 ("mm, page_alloc: recalculate the preferred zoneref if the context can ignore memory policies") and cd04ae1e2dc8 ("mm, oom: do not rely on TIF_MEMDIE for memory reserves access") to the current state. So even GFP_ATOMIC would now ignore mempolicies after the initial attempts fail - if the code worked as people thought it does. Link: http://lkml.kernel.org/r/20180612122624.8045-1-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17mm: skip invalid pages block at a time in zero_resv_unresv()Pavel Tatashin
The role of zero_resv_unavail() is to make sure that every struct page that is allocated but is not backed by memory that is accessible by kernel is zeroed and not in some uninitialized state. Since struct pages are allocated in blocks (2M pages in x86 case), we can skip pageblock_nr_pages at a time, when the first one is found to be invalid. This optimization may help since now on x86 every hole in e820 maps is marked as reserved in memblock, and thus will go through this function. This function is called before sched_clock() is initialized, so I used my x86 early boot clock patches to measure the performance improvement. With 1T hole on i7-8700 currently we would take 0.606918s of boot time, but with this optimization 0.001103s. Link: http://lkml.kernel.org/r/20180615155733.1175-1-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-14Merge tag 'pm-4.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add a new framework for CPU idle time injection, to be used by all of the idle injection code in the kernel in the future, fix some issues and add a number of relatively small extensions in multiple places. Specifics: - Add a new framework for CPU idle time injection (Daniel Lezcano). - Add AVS support to the armada-37xx cpufreq driver (Gregory CLEMENT). - Add support for current CPU frequency reporting to the ACPI CPPC cpufreq driver (George Cherian). - Rework the cooling device registration in the imx6q/thermal driver (Bastian Stender). - Make the pcc-cpufreq driver refuse to work with dynamic scaling governors on systems with many CPUs to avoid scalability issues with it (Rafael Wysocki). - Fix the intel_pstate driver to report different maximum CPU frequencies on systems where they really are different and to ignore the turbo active ratio if hardware-managend P-states (HWP) are in use; make it use the match_string() helper (Xie Yisheng, Srinivas Pandruvada). - Fix a minor deferred probe issue in the qcom-kryo cpufreq driver (Niklas Cassel). - Add a tracepoint for the tracking of frequency limits changes (from Andriod) to the cpufreq core (Ruchi Kandoi). - Fix a circular lock dependency between CPU hotplug and sysfs locking in the cpufreq core reported by lockdep (Waiman Long). - Avoid excessive error reports on driver registration failures in the ARM cpuidle driver (Sudeep Holla). - Add a new device links flag to the driver core to make links go away automatically on supplier driver removal (Vivek Gautam). - Eliminate potential race condition between system-wide power management transitions and system shutdown (Pingfan Liu). - Add a quirk to save NVS memory on system suspend for the ASUS 1025C laptop (Willy Tarreau). - Make more systems use suspend-to-idle (instead of ACPI S3) by default (Tristian Celestin). - Get rid of stack VLA usage in the low-level hibernation code on 64-bit x86 (Kees Cook). - Fix error handling in the hibernation core and mark an expected fall-through switch in it (Chengguang Xu, Gustavo Silva). - Extend the generic power domains (genpd) framework to support attaching a device to a power domain by name (Ulf Hansson). - Fix device reference counting and user limits initialization in the devfreq core (Arvind Yadav, Matthias Kaehlcke). - Fix a few issues in the rk3399_dmc devfreq driver and improve its documentation (Enric Balletbo i Serra, Lin Huang, Nick Milner). - Drop a redundant error message from the exynos-ppmu devfreq driver (Markus Elfring)" * tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (35 commits) PM / reboot: Eliminate race between reboot and suspend PM / hibernate: Mark expected switch fall-through cpufreq: intel_pstate: Ignore turbo active ratio in HWP cpufreq: Fix a circular lock dependency problem cpu/hotplug: Add a cpus_read_trylock() function x86/power/hibernate_64: Remove VLA usage cpufreq: trace frequency limits change cpufreq: intel_pstate: Show different max frequency with turbo 3 and HWP cpufreq: pcc-cpufreq: Disable dynamic scaling on many-CPU systems cpufreq: qcom-kryo: Silently error out on EPROBE_DEFER cpufreq / CPPC: Add cpuinfo_cur_freq support for CPPC cpufreq: armada-37xx: Add AVS support dt-bindings: marvell: Add documentation for the Armada 3700 AVS binding PM / devfreq: rk3399_dmc: Fix duplicated opp table on reload. PM / devfreq: Init user limits from OPP limits, not viceversa PM / devfreq: rk3399_dmc: fix spelling mistakes. PM / devfreq: rk3399_dmc: do not print error when get supply and clk defer. dt-bindings: devfreq: rk3399_dmc: move interrupts to be optional. PM / devfreq: rk3399_dmc: remove wait for dcf irq event. dt-bindings: clock: add rk3399 DDR3 standard speed bins. ...
2018-08-14Merge branches 'pm-core', 'pm-domains', 'pm-sleep', 'acpi-pm' and 'pm-cpuidle'Rafael J. Wysocki
Merge changes in the PM core, system-wide PM infrastructure, generic power domains (genpd) framework, ACPI PM infrastructure and cpuidle for 4.19. * pm-core: driver core: Add flag to autoremove device link on supplier unbind driver core: Rename flag AUTOREMOVE to AUTOREMOVE_CONSUMER * pm-domains: PM / Domains: Introduce dev_pm_domain_attach_by_name() PM / Domains: Introduce option to attach a device by name to genpd PM / Domains: dt: Add a power-domain-names property * pm-sleep: PM / reboot: Eliminate race between reboot and suspend PM / hibernate: Mark expected switch fall-through x86/power/hibernate_64: Remove VLA usage PM / hibernate: cast PAGE_SIZE to int when comparing with error code * acpi-pm: ACPI / PM: save NVS memory for ASUS 1025C laptop ACPI / PM: Default to s2idle in all machines supporting LP S0 * pm-cpuidle: ARM: cpuidle: silence error on driver registration failure
2018-08-06PM / reboot: Eliminate race between reboot and suspendPingfan Liu
At present, "systemctl suspend" and "shutdown" can run in parrallel. A system can suspend after devices_shutdown(), and resume. Then the shutdown task goes on to power off. This causes many devices are not really shut off. Hence replacing reboot_mutex with system_transition_mutex (renamed from pm_mutex) to achieve the exclusion. The renaming of pm_mutex as system_transition_mutex can be better to reflect the purpose of the mutex. Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-08-05mm: Allow non-direct-map arguments to free_reserved_area()Dave Hansen
free_reserved_area() takes pointers as arguments to show which addresses should be freed. However, it does this in a somewhat ambiguous way. If it gets a kernel direct map address, it always works. However, if it gets an address that is part of the kernel image alias mapping, it can fail. It fails if all of the following happen: * The specified address is part of the kernel image alias * Poisoning is requested (forcing a memset()) * The address is in a read-only portion of the kernel image The memset() fails on the read-only mapping, of course. free_reserved_area() *is* called both on the direct map and on kernel image alias addresses. We've just lucked out thus far that the kernel image alias areas it gets used on are read-write. I'm fairly sure this has been just a happy accident. It is quite easy to make free_reserved_area() work for all cases: just convert the address to a direct map address before doing the memset(), and do this unconditionally. There is little chance of a regression here because we previously did a virt_to_page() on the address for the memset, so we know these are not highmem pages for which virt_to_page() would fail. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@google.com Cc: aarcange@redhat.com Cc: jgross@suse.com Cc: jpoimboe@redhat.com Cc: gregkh@linuxfoundation.org Cc: peterz@infradead.org Cc: hughd@google.com Cc: torvalds@linux-foundation.org Cc: bp@alien8.de Cc: luto@kernel.org Cc: ak@linux.intel.com Cc: Kees Cook <keescook@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Hugh Dickins <hughd@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Link: https://lkml.kernel.org/r/20180802225826.1287AE3E@viggo.jf.intel.com
2018-07-16mm: don't do zero_resv_unavail if memmap is not allocatedPavel Tatashin
Moving zero_resv_unavail before memmap_init_zone(), caused a regression on x86-32. The cause is that we access struct pages before they are allocated when CONFIG_FLAT_NODE_MEM_MAP is used. free_area_init_nodes() zero_resv_unavail() mm_zero_struct_page(pfn_to_page(pfn)); <- struct page is not alloced free_area_init_node() if CONFIG_FLAT_NODE_MEM_MAP alloc_node_mem_map() memblock_virt_alloc_node_nopanic() <- struct page alloced here On the other hand memblock_virt_alloc_node_nopanic() zeroes all the memory that it returns, so we do not need to do zero_resv_unavail() here. Fixes: e181ae0c5db9 ("mm: zero unavailable pages before memmap init") Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Tested-by: Matt Hart <matt@mattface.org> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-14mm: zero unavailable pages before memmap initPavel Tatashin
We must zero struct pages for memory that is not backed by physical memory, or kernel does not have access to. Recently, there was a change which zeroed all memmap for all holes in e820. Unfortunately, it introduced a bug that is discussed here: https://www.spinics.net/lists/linux-mm/msg156764.html Linus, also saw this bug on his machine, and confirmed that reverting commit 124049decbb1 ("x86/e820: put !E820_TYPE_RAM regions into memblock.reserved") fixes the issue. The problem is that we incorrectly zero some struct pages after they were setup. The fix is to zero unavailable struct pages prior to initializing of struct pages. A more detailed fix should come later that would avoid double zeroing cases: one in __init_single_page(), the other one in zero_resv_unavail(). Fixes: 124049decbb1 ("x86/e820: put !E820_TYPE_RAM regions into memblock.reserved") Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-15mm: use octal not symbolic permissionsJoe Perches
mm/*.c files use symbolic and octal styles for permissions. Using octal and not symbolic permissions is preferred by many as more readable. https://lkml.org/lkml/2016/8/2/1945 Prefer the direct use of octal for permissions. Done using $ scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace mm/*.c and some typing. Before: $ git grep -P -w "0[0-7]{3,3}" mm | wc -l 44 After: $ git grep -P -w "0[0-7]{3,3}" mm | wc -l 86 Miscellanea: o Whitespace neatening around these conversions. Link: http://lkml.kernel.org/r/2e032ef111eebcd4c5952bae86763b541d373469.1522102887.git.joe@perches.com Signed-off-by: Joe Perches <joe@perches.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm, page_alloc: do not break __GFP_THISNODE by zonelist resetVlastimil Babka
In __alloc_pages_slowpath() we reset zonelist and preferred_zoneref for allocations that can ignore memory policies. The zonelist is obtained from current CPU's node. This is a problem for __GFP_THISNODE allocations that want to allocate on a different node, e.g. because the allocating thread has been migrated to a different CPU. This has been observed to break SLAB in our 4.4-based kernel, because there it relies on __GFP_THISNODE working as intended. If a slab page is put on wrong node's list, then further list manipulations may corrupt the list because page_to_nid() is used to determine which node's list_lock should be locked and thus we may take a wrong lock and race. Current SLAB implementation seems to be immune by luck thanks to commit 511e3a058812 ("mm/slab: make cache_grow() handle the page allocated on arbitrary node") but there may be others assuming that __GFP_THISNODE works as promised. We can fix it by simply removing the zonelist reset completely. There is actually no reason to reset it, because memory policies and cpusets don't affect the zonelist choice in the first place. This was different when commit 183f6371aac2 ("mm: ignore mempolicies when using ALLOC_NO_WATERMARK") introduced the code, as mempolicies provided their own restricted zonelists. We might consider this for 4.17 although I don't know if there's anything currently broken. SLAB is currently not affected, but in kernels older than 4.7 that don't yet have 511e3a058812 ("mm/slab: make cache_grow() handle the page allocated on arbitrary node") it is. That's at least 4.4 LTS. Older ones I'll have to check. So stable backports should be more important, but will have to be reviewed carefully, as the code went through many changes. BTW I think that also the ac->preferred_zoneref reset is currently useless if we don't also reset ac->nodemask from a mempolicy to NULL first (which we probably should for the OOM victims etc?), but I would leave that for a separate patch. Link: http://lkml.kernel.org/r/20180525130853.13915-1-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Fixes: 183f6371aac2 ("mm: ignore mempolicies when using ALLOC_NO_WATERMARK") Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm: combine LRU and main union in struct pageMatthew Wilcox
This gives us five words of space in a single union in struct page. The compound_mapcount moves position (from offset 24 to offset 20) on 64-bit systems, but that does not seem likely to cause any trouble. Link: http://lkml.kernel.org/r/20180518194519.3820-11-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm: use page->deferred_listMatthew Wilcox
Now that we can represent the location of 'deferred_list' in C instead of comments, make use of that ability. Link: http://lkml.kernel.org/r/20180518194519.3820-9-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm: split page_type out from _mapcountMatthew Wilcox
We're already using a union of many fields here, so stop abusing the _mapcount and make page_type its own field. That implies renaming some of the machinery that creates PageBuddy, PageBalloon and PageKmemcg; bring back the PG_buddy, PG_balloon and PG_kmemcg names. As suggested by Kirill, make page_type a bitmask. Because it starts out life as -1 (thanks to sharing the storage with _mapcount), setting a page flag means clearing the appropriate bit. This gives us space for probably twenty or so extra bits (depending how paranoid we want to be about _mapcount underflow). Link: http://lkml.kernel.org/r/20180518194519.3820-3-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm/page_alloc.c: remove useless parameter of finalise_ac()Huaisheng Ye
finalise_ac() has parameter order which is not used at all. Remove it. Signed-off-by: Huaisheng Ye <yehs1@lenovo.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm: move is_pageblock_removable_nolock() to mm/memory_hotplug.cMathieu Malaterre
is_pageblock_removable_nolock() is not used outside of mm/memory_hotplug.c. Move it next to unique caller is_mem_section_removable() and make it static. Remove prototype in <linux/memory_hotplug.h> to silence gcc warning (W=1): mm/page_alloc.c:7704:6: warning: no previous prototype for `is_pageblock_removable_nolock' [-Wmissing-prototypes] Link: http://lkml.kernel.org/r/20180509190001.24789-1-malat@debian.org Signed-off-by: Mathieu Malaterre <malat@debian.org> Suggested-by: Michal Hocko <mhocko@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07lockdep: fix fs_reclaim annotationOmar Sandoval
While revisiting my Btrfs swapfile series [1], I introduced a situation in which reclaim would lock i_rwsem, and even though the swapon() path clearly made GFP_KERNEL allocations while holding i_rwsem, I got no complaints from lockdep. It turns out that the rework of the fs_reclaim annotation was broken: if the current task has PF_MEMALLOC set, we don't acquire the dummy fs_reclaim lock, but when reclaiming we always check this _after_ we've just set the PF_MEMALLOC flag. In most cases, we can fix this by moving the fs_reclaim_{acquire,release}() outside of the memalloc_noreclaim_{save,restore}(), althought kswapd is slightly different. After applying this, I got the expected lockdep splats. 1: https://lwn.net/Articles/625412/ Link: http://lkml.kernel.org/r/9f8aa70652a98e98d7c4de0fc96a4addcee13efe.1523778026.git.osandov@fb.com Fixes: d92a8cfcb37e ("locking/lockdep: Rework FS_RECLAIM annotation") Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm/page_alloc: remove realsize in free_area_init_core()Wei Yang
Highmem's realsize always equals to freesize, so it is not necessary to spare a variable to record this. Link: http://lkml.kernel.org/r/20180413083859.65888-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-25mm, memory_hotplug: make has_unmovable_pages more robustMichal Hocko
Oscar has reported: : Due to an unfortunate setting with movablecore, memblocks containing bootmem : memory (pages marked by get_page_bootmem()) ended up marked in zone_movable. : So while trying to remove that memory, the system failed in do_migrate_range : and __offline_pages never returned. : : This can be reproduced by running : qemu-system-x86_64 -m 6G,slots=8,maxmem=8G -numa node,mem=4096M -numa node,mem=2048M : and movablecore=4G kernel command line : : linux kernel: BIOS-provided physical RAM map: : linux kernel: BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable : linux kernel: BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved : linux kernel: BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved : linux kernel: BIOS-e820: [mem 0x0000000000100000-0x00000000bffdffff] usable : linux kernel: BIOS-e820: [mem 0x00000000bffe0000-0x00000000bfffffff] reserved : linux kernel: BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved : linux kernel: BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved : linux kernel: BIOS-e820: [mem 0x0000000100000000-0x00000001bfffffff] usable : linux kernel: NX (Execute Disable) protection: active : linux kernel: SMBIOS 2.8 present. : linux kernel: DMI: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org : linux kernel: Hypervisor detected: KVM : linux kernel: e820: update [mem 0x00000000-0x00000fff] usable ==> reserved : linux kernel: e820: remove [mem 0x000a0000-0x000fffff] usable : linux kernel: last_pfn = 0x1c0000 max_arch_pfn = 0x400000000 : : linux kernel: SRAT: PXM 0 -> APIC 0x00 -> Node 0 : linux kernel: SRAT: PXM 1 -> APIC 0x01 -> Node 1 : linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x00000000-0x0009ffff] : linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x00100000-0xbfffffff] : linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0x13fffffff] : linux kernel: ACPI: SRAT: Node 1 PXM 1 [mem 0x140000000-0x1bfffffff] : linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x1c0000000-0x43fffffff] hotplug : linux kernel: NUMA: Node 0 [mem 0x00000000-0x0009ffff] + [mem 0x00100000-0xbfffffff] -> [mem 0x0 : linux kernel: NUMA: Node 0 [mem 0x00000000-0xbfffffff] + [mem 0x100000000-0x13fffffff] -> [mem 0 : linux kernel: NODE_DATA(0) allocated [mem 0x13ffd6000-0x13fffffff] : linux kernel: NODE_DATA(1) allocated [mem 0x1bffd3000-0x1bfffcfff] : : zoneinfo shows that the zone movable is placed into both numa nodes: : Node 0, zone Movable : pages free 160140 : min 1823 : low 2278 : high 2733 : spanned 262144 : present 262144 : managed 245670 : Node 1, zone Movable : pages free 448427 : min 3827 : low 4783 : high 5739 : spanned 524288 : present 524288 : managed 515766 Note how only Node 0 has a hutplugable memory region which would rule it out from the early memblock allocations (most likely memmap). Node1 will surely contain memmaps on the same node and those would prevent offlining to succeed. So this is arguably a configuration issue. Although one could argue that we should be more clever and rule early allocations from the zone movable. This would be correct but probably not worth the effort considering what a hack movablecore is. Anyway, We could do better for those cases though. We rely on start_isolate_page_range resp. has_unmovable_pages to do their job. The first one isolates the whole range to be offlined so that we do not allocate from it anymore and the later makes sure we are not stumbling over non-migrateable pages. has_unmovable_pages is overly optimistic, however. It doesn't check all the pages if we are withing zone_movable because we rely that those pages will be always migrateable. As it turns out we are still not perfect there. While bootmem pages in zonemovable sound like a clear bug which should be fixed let's remove the optimization for now and warn if we encounter unmovable pages in zone_movable in the meantime. That should help for now at least. Btw. this wasn't a real problem until commit 72b39cfc4d75 ("mm, memory_hotplug: do not fail offlining too early") because we used to have a small number of retries and then failed. This turned out to be too fragile though. Link: http://lkml.kernel.org/r/20180523125555.30039-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Oscar Salvador <osalvador@techadventures.net> Tested-by: Oscar Salvador <osalvador@techadventures.net> Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-24Revert "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE"Joonsoo Kim
This reverts the following commits that change CMA design in MM. 3d2054ad8c2d ("ARM: CMA: avoid double mapping to the CMA area if CONFIG_HIGHMEM=y") 1d47a3ec09b5 ("mm/cma: remove ALLOC_CMA") bad8c6c0b114 ("mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE") Ville reported a following error on i386. Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) microcode: microcode updated early to revision 0x4, date = 2013-06-28 Initializing CPU#0 Initializing HighMem for node 0 (000377fe:00118000) Initializing Movable for node 0 (00000001:00118000) BUG: Bad page state in process swapper pfn:377fe page:f53effc0 count:0 mapcount:-127 mapping:00000000 index:0x0 flags: 0x80000000() raw: 80000000 00000000 00000000 ffffff80 00000000 00000100 00000200 00000001 page dumped because: nonzero mapcount Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 4.17.0-rc5-elk+ #145 Hardware name: Dell Inc. Latitude E5410/03VXMC, BIOS A15 07/11/2013 Call Trace: dump_stack+0x60/0x96 bad_page+0x9a/0x100 free_pages_check_bad+0x3f/0x60 free_pcppages_bulk+0x29d/0x5b0 free_unref_page_commit+0x84/0xb0 free_unref_page+0x3e/0x70 __free_pages+0x1d/0x20 free_highmem_page+0x19/0x40 add_highpages_with_active_regions+0xab/0xeb set_highmem_pages_init+0x66/0x73 mem_init+0x1b/0x1d7 start_kernel+0x17a/0x363 i386_start_kernel+0x95/0x99 startup_32_smp+0x164/0x168 The reason for this error is that the span of MOVABLE_ZONE is extended to whole node span for future CMA initialization, and, normal memory is wrongly freed here. I submitted the fix and it seems to work, but, another problem happened. It's so late time to fix the later problem so I decide to reverting the series. Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Acked-by: Laura Abbott <labbott@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11xen, mm: allow deferred page initialization for xen pv domainsPavel Tatashin
Juergen Gross noticed that commit f7f99100d8d ("mm: stop zeroing memory during allocation in vmemmap") broke XEN PV domains when deferred struct page initialization is enabled. This is because the xen's PagePinned() flag is getting erased from struct pages when they are initialized later in boot. Juergen fixed this problem by disabling deferred pages on xen pv domains. It is desirable, however, to have this feature available as it reduces boot time. This fix re-enables the feature for pv-dmains, and fixes the problem the following way: The fix is to delay setting PagePinned flag until struct pages for all allocated memory are initialized, i.e. until after free_all_bootmem(). A new x86_init.hyper op init_after_bootmem() is called to let xen know that boot allocator is done, and hence struct pages for all the allocated memory are now initialized. If deferred page initialization is enabled, the rest of struct pages are going to be initialized later in boot once page_alloc_init_late() is called. xen_after_bootmem() walks page table's pages and marks them pinned. Link: http://lkml.kernel.org/r/20180226160112.24724-2-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Tested-by: Juergen Gross <jgross@suse.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andy Lutomirski <luto@kernel.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Mathias Krause <minipli@googlemail.com> Cc: Jinbum Park <jinb.park7@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Baoquan He <bhe@redhat.com> Cc: Jia Zhang <zhang.jia@linux.alibaba.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11mm/cma: remove ALLOC_CMAJoonsoo Kim
Now, all reserved pages for CMA region are belong to the ZONE_MOVABLE and it only serves for a request with GFP_HIGHMEM && GFP_MOVABLE. Therefore, we don't need to maintain ALLOC_CMA at all. Link: http://lkml.kernel.org/r/1512114786-5085-3-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLEJoonsoo Kim
Patch series "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE", v2. 0. History This patchset is the follow-up of the discussion about the "Introduce ZONE_CMA (v7)" [1]. Please reference it if more information is needed. 1. What does this patch do? This patch changes the management way for the memory of the CMA area in the MM subsystem. Currently the memory of the CMA area is managed by the zone where their pfn is belong to. However, this approach has some problems since MM subsystem doesn't have enough logic to handle the situation that different characteristic memories are in a single zone. To solve this issue, this patch try to manage all the memory of the CMA area by using the MOVABLE zone. In MM subsystem's point of view, characteristic of the memory on the MOVABLE zone and the memory of the CMA area are the same. So, managing the memory of the CMA area by using the MOVABLE zone will not have any problem. 2. Motivation There are some problems with current approach. See following. Although these problem would not be inherent and it could be fixed without this conception change, it requires many hooks addition in various code path and it would be intrusive to core MM and would be really error-prone. Therefore, I try to solve them with this new approach. Anyway, following is the problems of the current implementation. o CMA memory utilization First, following is the freepage calculation logic in MM. - For movable allocation: freepage = total freepage - For unmovable allocation: freepage = total freepage - CMA freepage Freepages on the CMA area is used after the normal freepages in the zone where the memory of the CMA area is belong to are exhausted. At that moment that the number of the normal freepages is zero, so - For movable allocation: freepage = total freepage = CMA freepage - For unmovable allocation: freepage = 0 If unmovable allocation comes at this moment, allocation request would fail to pass the watermark check and reclaim is started. After reclaim, there would exist the normal freepages so freepages on the CMA areas would not be used. FYI, there is another attempt [2] trying to solve this problem in lkml. And, as far as I know, Qualcomm also has out-of-tree solution for this problem. Useless reclaim: There is no logic to distinguish CMA pages in the reclaim path. Hence, CMA page is reclaimed even if the system just needs the page that can be usable for the kernel allocation. Atomic allocation failure: This is also related to the fallback allocation policy for the memory of the CMA area. Consider the situation that the number of the normal freepages is *zero* since the bunch of the movable allocation requests come. Kswapd would not be woken up due to following freepage calculation logic. - For movable allocation: freepage = total freepage = CMA freepage If atomic unmovable allocation request comes at this moment, it would fails due to following logic. - For unmovable allocation: freepage = total freepage - CMA freepage = 0 It was reported by Aneesh [3]. Useless compaction: Usual high-order allocation request is unmovable allocation request and it cannot be served from the memory of the CMA area. In compaction, migration scanner try to migrate the page in the CMA area and make high-order page there. As mentioned above, it cannot be usable for the unmovable allocation request so it's just waste. 3. Current approach and new approach Current approach is that the memory of the CMA area is managed by the zone where their pfn is belong to. However, these memory should be distinguishable since they have a strong limitation. So, they are marked as MIGRATE_CMA in pageblock flag and handled specially. However, as mentioned in section 2, the MM subsystem doesn't have enough logic to deal with this special pageblock so many problems raised. New approach is that the memory of the CMA area is managed by the MOVABLE zone. MM already have enough logic to deal with special zone like as HIGHMEM and MOVABLE zone. So, managing the memory of the CMA area by the MOVABLE zone just naturally work well because constraints for the memory of the CMA area that the memory should always be migratable is the same with the constraint for the MOVABLE zone. There is one side-effect for the usability of the memory of the CMA area. The use of MOVABLE zone is only allowed for a request with GFP_HIGHMEM && GFP_MOVABLE so now the memory of the CMA area is also only allowed for this gfp flag. Before this patchset, a request with GFP_MOVABLE can use them. IMO, It would not be a big issue since most of GFP_MOVABLE request also has GFP_HIGHMEM flag. For example, file cache page and anonymous page. However, file cache page for blockdev file is an exception. Request for it has no GFP_HIGHMEM flag. There is pros and cons on this exception. In my experience, blockdev file cache pages are one of the top reason that causes cma_alloc() to fail temporarily. So, we can get more guarantee of cma_alloc() success by discarding this case. Note that there is no change in admin POV since this patchset is just for internal implementation change in MM subsystem. Just one minor difference for admin is that the memory stat for CMA area will be printed in the MOVABLE zone. That's all. 4. Result Following is the experimental result related to utilization problem. 8 CPUs, 1024 MB, VIRTUAL MACHINE make -j16 <Before> CMA area: 0 MB 512 MB Elapsed-time: 92.4 186.5 pswpin: 82 18647 pswpout: 160 69839 <After> CMA : 0 MB 512 MB Elapsed-time: 93.1 93.4 pswpin: 84 46 pswpout: 183 92 akpm: "kernel test robot" reported a 26% improvement in vm-scalability.throughput: http://lkml.kernel.org/r/20180330012721.GA3845@yexl-desktop [1]: lkml.kernel.org/r/1491880640-9944-1-git-send-email-iamjoonsoo.kim@lge.com [2]: https://lkml.org/lkml/2014/10/15/623 [3]: http://www.spinics.net/lists/linux-mm/msg100562.html Link: http://lkml.kernel.org/r/1512114786-5085-2-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11mm/page_alloc: don't reserve ZONE_HIGHMEM for ZONE_MOVABLE requestJoonsoo Kim
Freepage on ZONE_HIGHMEM doesn't work for kernel memory so it's not that important to reserve. When ZONE_MOVABLE is used, this problem would theorectically cause to decrease usable memory for GFP_HIGHUSER_MOVABLE allocation request which is mainly used for page cache and anon page allocation. So, fix it by setting 0 to sysctl_lowmem_reserve_ratio[ZONE_HIGHMEM]. And, defining sysctl_lowmem_reserve_ratio array by MAX_NR_ZONES - 1 size makes code complex. For example, if there is highmem system, following reserve ratio is activated for *NORMAL ZONE* which would be easyily misleading people. #ifdef CONFIG_HIGHMEM 32 #endif This patch also fixes this situation by defining sysctl_lowmem_reserve_ratio array by MAX_NR_ZONES and place "#ifdef" to right place. Link: http://lkml.kernel.org/r/1504672525-17915-1-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Tony Lindgren <tony@atomide.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: <linux-api@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11mm: treat indirectly reclaimable memory as available in MemAvailableRoman Gushchin
Adjust /proc/meminfo MemAvailable calculation by adding the amount of indirectly reclaimable memory (rounded to the PAGE_SIZE). Link: http://lkml.kernel.org/r/20180305133743.12746-4-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm/page_isolation.c: make start_isolate_page_range() fail if already isolatedMike Kravetz
start_isolate_page_range() is used to set the migrate type of a set of pageblocks to MIGRATE_ISOLATE while attempting to start a migration operation. It assumes that only one thread is calling it for the specified range. This routine is used by CMA, memory hotplug and gigantic huge pages. Each of these users synchronize access to the range within their subsystem. However, two subsystems (CMA and gigantic huge pages for example) could attempt operations on the same range. If this happens, one thread may 'undo' the work another thread is doing. This can result in pageblocks being incorrectly left marked as MIGRATE_ISOLATE and therefore not available for page allocation. What is ideally needed is a way to synchronize access to a set of pageblocks that are undergoing isolation and migration. The only thing we know about these pageblocks is that they are all in the same zone. A per-node mutex is too coarse as we want to allow multiple operations on different ranges within the same zone concurrently. Instead, we will use the migration type of the pageblocks themselves as a form of synchronization. start_isolate_page_range sets the migration type on a set of page- blocks going in order from the one associated with the smallest pfn to the largest pfn. The zone lock is acquired to check and set the migration type. When going through the list of pageblocks check if MIGRATE_ISOLATE is already set. If so, this indicates another thread is working on this pageblock. We know exactly which pageblocks we set, so clean up by undo those and return -EBUSY. This allows start_isolate_page_range to serve as a synchronization mechanism and will allow for more general use of callers making use of these interfaces. Update comments in alloc_contig_range to reflect this new functionality. Each CPU holds the associated zone lock to modify or examine the migration type of a pageblock. And, it will only examine/update a single pageblock per lock acquire/release cycle. Link: http://lkml.kernel.org/r/20180309224731.16978-1-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm, page_alloc: wakeup kcompactd even if kswapd cannot free more memoryDavid Rientjes
Kswapd will not wakeup if per-zone watermarks are not failing or if too many previous attempts at background reclaim have failed. This can be true if there is a lot of free memory available. For high- order allocations, kswapd is responsible for waking up kcompactd for background compaction. If the zone is not below its watermarks or reclaim has recently failed (lots of free memory, nothing left to reclaim), kcompactd does not get woken up. When __GFP_DIRECT_RECLAIM is not allowed, allow kcompactd to still be woken up even if kswapd will not reclaim. This allows high-order allocations, such as thp, to still trigger background compaction even when the zone has an abundance of free memory. Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803111659420.209721@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm/free_pcppages_bulk: prefetch buddy while not holding lockAaron Lu
When a page is freed back to the global pool, its buddy will be checked to see if it's possible to do a merge. This requires accessing buddy's page structure and that access could take a long time if it's cache cold. This patch adds a prefetch to the to-be-freed page's buddy outside of zone->lock in hope of accessing buddy's page structure later under zone->lock will be faster. Since we *always* do buddy merging and check an order-0 page's buddy to try to merge it when it goes into the main allocator, the cacheline will always come in, i.e. the prefetched data will never be unused. Normally, the number of prefetch will be pcp->batch(default=31 and has an upper limit of (PAGE_SHIFT * 8)=96 on x86_64) but in the case of pcp's pages get all drained, it will be pcp->count which has an upper limit of pcp->high. pcp->high, although has a default value of 186 (pcp->batch=31 * 6), can be changed by user through /proc/sys/vm/percpu_pagelist_fraction and there is no software upper limit so could be large, like several thousand. For this reason, only the first pcp->batch number of page's buddy structure is prefetched to avoid excessive prefetching. In the meantime, there are two concerns: 1. the prefetch could potentially evict existing cachelines, especially for L1D cache since it is not huge 2. there is some additional instruction overhead, namely calculating buddy pfn twice For 1, it's hard to say, this microbenchmark though shows good result but the actual benefit of this patch will be workload/CPU dependant; For 2, since the calculation is a XOR on two local variables, it's expected in many cases that cycles spent will be offset by reduced memory latency later. This is especially true for NUMA machines where multiple CPUs are contending on zone->lock and the most time consuming part under zone->lock is the wait of 'struct page' cacheline of the to-be-freed pages and their buddies. Test with will-it-scale/page_fault1 full load: kernel Broadwell(2S) Skylake(2S) Broadwell(4S) Skylake(4S) v4.16-rc2+ 9034215 7971818 13667135 15677465 patch2/3 9536374 +5.6% 8314710 +4.3% 14070408 +3.0% 16675866 +6.4% this patch 10180856 +6.8% 8506369 +2.3% 14756865 +4.9% 17325324 +3.9% Note: this patch's performance improvement percent is against patch2/3. (Changelog stolen from Dave Hansen and Mel Gorman's comments at http://lkml.kernel.org/r/148a42d8-8306-2f2f-7f7c-86bc118f8ccd@intel.com) [aaron.lu@intel.com: use helper function, avoid disordering pages] Link: http://lkml.kernel.org/r/20180301062845.26038-4-aaron.lu@intel.com Link: http://lkml.kernel.org/r/20180320113146.GB24737@intel.com [aaron.lu@intel.com: v4] Link: http://lkml.kernel.org/r/20180301062845.26038-4-aaron.lu@intel.com Link: http://lkml.kernel.org/r/20180309082431.GB30868@intel.com Link: http://lkml.kernel.org/r/20180301062845.26038-4-aaron.lu@intel.com Signed-off-by: Aaron Lu <aaron.lu@intel.com> Suggested-by: Ying Huang <ying.huang@intel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Kemi Wang <kemi.wang@intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm/free_pcppages_bulk: do not hold lock when picking pages to freeAaron Lu
When freeing a batch of pages from Per-CPU-Pages(PCP) back to buddy, the zone->lock is held and then pages are chosen from PCP's migratetype list. While there is actually no need to do this 'choose part' under lock since it's PCP pages, the only CPU that can touch them is us and irq is also disabled. Moving this part outside could reduce lock held time and improve performance. Test with will-it-scale/page_fault1 full load: kernel Broadwell(2S) Skylake(2S) Broadwell(4S) Skylake(4S) v4.16-rc2+ 9034215 7971818 13667135 15677465 this patch 9536374 +5.6% 8314710 +4.3% 14070408 +3.0% 16675866 +6.4% What the test does is: starts $nr_cpu processes and each will repeatedly do the following for 5 minutes: - mmap 128M anonymouse space - write access to that space - munmap. The score is the aggregated iteration. https://github.com/antonblanchard/will-it-scale/blob/master/tests/page_fault1.c Link: http://lkml.kernel.org/r/20180301062845.26038-3-aaron.lu@intel.com Signed-off-by: Aaron Lu <aaron.lu@intel.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Kemi Wang <kemi.wang@intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm/free_pcppages_bulk: update pcp->count insideAaron Lu
Matthew Wilcox found that all callers of free_pcppages_bulk() currently update pcp->count immediately after so it's natural to do it inside free_pcppages_bulk(). No functionality or performance change is expected from this patch. Link: http://lkml.kernel.org/r/20180301062845.26038-2-aaron.lu@intel.com Signed-off-by: Aaron Lu <aaron.lu@intel.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Huang Ying <ying.huang@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kemi Wang <kemi.wang@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm, page_alloc: move mirrored_kernelcore to __meminitdataDavid Rientjes
mirrored_kernelcore can be in __meminitdata, so move it there. At the same time, fixup section specifiers to be after the name of the variable per checkpatch. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802121623280.179479@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm, page_alloc: extend kernelcore and movablecore for percentDavid Rientjes
Both kernelcore= and movablecore= can be used to define the amount of ZONE_NORMAL and ZONE_MOVABLE on a system, respectively. This requires the system memory capacity to be known when specifying the command line, however. This introduces the ability to define both kernelcore= and movablecore= as a percentage of total system memory. This is convenient for systems software that wants to define the amount of ZONE_MOVABLE, for example, as a proportion of a system's memory rather than a hardcoded byte value. To define the percentage, the final character of the parameter should be a '%'. mhocko: "why is anyone using these options nowadays?" rientjes: : : Fragmentation of non-__GFP_MOVABLE pages due to low on memory : situations can pollute most pageblocks on the system, as much as 1GB of : slab being fragmented over 128GB of memory, for example. When the : amount of kernel memory is well bounded for certain systems, it is : better to aggressively reclaim from existing MIGRATE_UNMOVABLE : pageblocks rather than eagerly fallback to others. : : We have additional patches that help with this fragmentation if you're : interested, specifically kcompactd compaction of MIGRATE_UNMOVABLE : pageblocks triggered by fallback of non-__GFP_MOVABLE allocations and : draining of pcp lists back to the zone free area to prevent stranding. [rientjes@google.com: updates] Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802131700160.71590@chino.kir.corp.google.com Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802121622470.179479@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm/memory_hotplug: optimize memory hotplugPavel Tatashin
During memory hotplugging we traverse struct pages three times: 1. memset(0) in sparse_add_one_section() 2. loop in __add_section() to set do: set_page_node(page, nid); and SetPageReserved(page); 3. loop in memmap_init_zone() to call __init_single_pfn() This patch removes the first two loops, and leaves only loop 3. All struct pages are initialized in one place, the same as it is done during boot. The benefits: - We improve memory hotplug performance because we are not evicting the cache several times and also reduce loop branching overhead. - Remove condition from hotpath in __init_single_pfn(), that was added in order to fix the problem that was reported by Bharata in the above email thread, thus also improve performance during normal boot. - Make memory hotplug more similar to the boot memory initialization path because we zero and initialize struct pages only in one function. - Simplifies memory hotplug struct page initialization code, and thus enables future improvements, such as multi-threading the initialization of struct pages in order to improve hotplug performance even further on larger machines. [pasha.tatashin@oracle.com: v5] Link: http://lkml.kernel.org/r/20180228030308.1116-7-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180215165920.8570-7-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Baoquan He <bhe@redhat.com> Cc: Bharata B Rao <bharata@linux.vnet.ibm.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm: initialize pages on demand during bootPavel Tatashin
Deferred page initialization allows the boot cpu to initialize a small subset of the system's pages early in boot, with other cpus doing the rest later on. It is, however, problematic to know how many pages the kernel needs during boot. Different modules and kernel parameters may change the requirement, so the boot cpu either initializes too many pages or runs out of memory. To fix that, initialize early pages on demand. This ensures the kernel does the minimum amount of work to initialize pages during boot and leaves the rest to be divided in the multithreaded initialization path (deferred_init_memmap). The on-demand code is permanently disabled using static branching once deferred pages are initialized. After the static branch is changed to false, the overhead is up-to two branch-always instructions if the zone watermark check fails or if rmqueue fails. Sergey Senozhatsky noticed that while deferred pages currently make sense only on NUMA machines (we start one thread per latency node), CONFIG_NUMA is not a requirement for CONFIG_DEFERRED_STRUCT_PAGE_INIT, so that is also must be addressed in the patch. [akpm@linux-foundation.org: fix typo in comment, make deferred_pages static] [pasha.tatashin@oracle.com: fix min() type mismatch warning] Link: http://lkml.kernel.org/r/20180212164543.26592-1-pasha.tatashin@oracle.com [pasha.tatashin@oracle.com: use zone_to_nid() in deferred_grow_zone()] Link: http://lkml.kernel.org/r/20180214163343.21234-2-pasha.tatashin@oracle.com [pasha.tatashin@oracle.com: might_sleep warning] Link: http://lkml.kernel.org/r/20180306192022.28289-1-pasha.tatashin@oracle.com [akpm@linux-foundation.org: s/spin_lock/spin_lock_irq/ in page_alloc_init_late()] [pasha.tatashin@oracle.com: v5] Link: http://lkml.kernel.org/r/20180309220807.24961-3-pasha.tatashin@oracle.com [akpm@linux-foundation.org: tweak comments] [pasha.tatashin@oracle.com: v6] Link: http://lkml.kernel.org/r/20180313182355.17669-3-pasha.tatashin@oracle.com [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20180209192216.20509-2-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Gioh Kim <gi-oh.kim@profitbricks.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm: disable interrupts while initializing deferred pagesPavel Tatashin
Vlastimil Babka reported about a window issue during which when deferred pages are initialized, and the current version of on-demand initialization is finished, allocations may fail. While this is highly unlikely scenario, since this kind of allocation request must be large, and must come from interrupt handler, we still want to cover it. We solve this by initializing deferred pages with interrupts disabled, and holding node_size_lock spin lock while pages in the node are being initialized. The on-demand deferred page initialization that comes later will use the same lock, and thus synchronize with deferred_init_memmap(). It is unlikely for threads that initialize deferred pages to be interrupted. They run soon after smp_init(), but before modules are initialized, and long before user space programs. This is why there is no adverse effect of having these threads running with interrupts disabled. [pasha.tatashin@oracle.com: v6] Link: http://lkml.kernel.org/r/20180313182355.17669-2-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180309220807.24961-2-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Gioh Kim <gi-oh.kim@profitbricks.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05mm/migrate: rename migration reason MR_CMA to MR_CONTIG_RANGEAnshuman Khandual
alloc_contig_range() initiates compaction and eventual migration for the purpose of either CMA or HugeTLB allocations. At present, the reason code remains the same MR_CMA for either of these cases. Let's make it MR_CONTIG_RANGE which will appropriately reflect the reason code in both these cases. Link: http://lkml.kernel.org/r/20180202091518.18798-1-khandual@linux.vnet.ibm.com Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-02Merge tag 'arch-removal' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pul removal of obsolete architecture ports from Arnd Bergmann: "This removes the entire architecture code for blackfin, cris, frv, m32r, metag, mn10300, score, and tile, including the associated device drivers. I have been working with the (former) maintainers for each one to ensure that my interpretation was right and the code is definitely unused in mainline kernels. Many had fond memories of working on the respective ports to start with and getting them included in upstream, but also saw no point in keeping the port alive without any users. In the end, it seems that while the eight architectures are extremely different, they all suffered the same fate: There was one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem, which was more costly than licensing newer off-the-shelf CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems that all the SoC product lines are still around, but have not used the custom CPU architectures for several years at this point. In contrast, CPU instruction sets that remain popular and have actively maintained kernel ports tend to all be used across multiple licensees. [ See the new nds32 port merged in the previous commit for the next generation of "one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem" - Linus ] The removal came out of a discussion that is now documented at https://lwn.net/Articles/748074/. Unlike the original plans, I'm not marking any ports as deprecated but remove them all at once after I made sure that they are all unused. Some architectures (notably tile, mn10300, and blackfin) are still being shipped in products with old kernels, but those products will never be updated to newer kernel releases. After this series, we still have a few architectures without mainline gcc support: - unicore32 and hexagon both have very outdated gcc releases, but the maintainers promised to work on providing something newer. At least in case of hexagon, this will only be llvm, not gcc. - openrisc, risc-v and nds32 are still in the process of finishing their support or getting it added to mainline gcc in the first place. They all have patched gcc-7.3 ports that work to some degree, but complete upstream support won't happen before gcc-8.1. Csky posted their first kernel patch set last week, their situation will be similar [ Palmer Dabbelt points out that RISC-V support is in mainline gcc since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]" This really says it all: 2498 files changed, 95 insertions(+), 467668 deletions(-) * tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits) MAINTAINERS: UNICORE32: Change email account staging: iio: remove iio-trig-bfin-timer driver tty: hvc: remove tile driver tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers serial: remove tile uart driver serial: remove m32r_sio driver serial: remove blackfin drivers serial: remove cris/etrax uart drivers usb: Remove Blackfin references in USB support usb: isp1362: remove blackfin arch glue usb: musb: remove blackfin port usb: host: remove tilegx platform glue pwm: remove pwm-bfin driver i2c: remove bfin-twi driver spi: remove blackfin related host drivers watchdog: remove bfin_wdt driver can: remove bfin_can driver mmc: remove bfin_sdh driver input: misc: remove blackfin rotary driver input: keyboard: remove bf54x driver ...
2018-03-22Revert "mm: page_alloc: skip over regions of invalid pfns where possible"Daniel Vacek
This reverts commit b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible"). The commit is meant to be a boot init speed up skipping the loop in memmap_init_zone() for invalid pfns. But given some specific memory mapping on x86_64 (or more generally theoretically anywhere but on arm with CONFIG_HAVE_ARCH_PFN_VALID) the implementation also skips valid pfns which is plain wrong and causes 'kernel BUG at mm/page_alloc.c:1389!' crash> log | grep -e BUG -e RIP -e Call.Trace -e move_freepages_block -e rmqueue -e freelist -A1 kernel BUG at mm/page_alloc.c:1389! invalid opcode: 0000 [#1] SMP -- RIP: 0010: move_freepages+0x15e/0x160 -- Call Trace: move_freepages_block+0x73/0x80 __rmqueue+0x263/0x460 get_page_from_freelist+0x7e1/0x9e0 __alloc_pages_nodemask+0x176/0x420 -- crash> page_init_bug -v | grep RAM <struct resource 0xffff88067fffd2f8> 1000 - 9bfff System RAM (620.00 KiB) <struct resource 0xffff88067fffd3a0> 100000 - 430bffff System RAM ( 1.05 GiB = 1071.75 MiB = 1097472.00 KiB) <struct resource 0xffff88067fffd410> 4b0c8000 - 4bf9cfff System RAM ( 14.83 MiB = 15188.00 KiB) <struct resource 0xffff88067fffd480> 4bfac000 - 646b1fff System RAM (391.02 MiB = 400408.00 KiB) <struct resource 0xffff88067fffd560> 7b788000 - 7b7fffff System RAM (480.00 KiB) <struct resource 0xffff88067fffd640> 100000000 - 67fffffff System RAM ( 22.00 GiB) crash> page_init_bug | head -6 <struct resource 0xffff88067fffd560> 7b788000 - 7b7fffff System RAM (480.00 KiB) <struct page 0xffffea0001ede200> 1fffff00000000 0 <struct pglist_data 0xffff88047ffd9000> 1 <struct zone 0xffff88047ffd9800> DMA32 4096 1048575 <struct page 0xffffea0001ede200> 505736 505344 <struct page 0xffffea0001ed8000> 505855 <struct page 0xffffea0001edffc0> <struct page 0xffffea0001ed8000> 0 0 <struct pglist_data 0xffff88047ffd9000> 0 <struct zone 0xffff88047ffd9000> DMA 1 4095 <struct page 0xffffea0001edffc0> 1fffff00000400 0 <struct pglist_data 0xffff88047ffd9000> 1 <struct zone 0xffff88047ffd9800> DMA32 4096 1048575 BUG, zones differ! crash> kmem -p 77fff000 78000000 7b5ff000 7b600000 7b787000 7b788000 PAGE PHYSICAL MAPPING INDEX CNT FLAGS ffffea0001e00000 78000000 0 0 0 0 ffffea0001ed7fc0 7b5ff000 0 0 0 0 ffffea0001ed8000 7b600000 0 0 0 0 <<<< ffffea0001ede1c0 7b787000 0 0 0 0 ffffea0001ede200 7b788000 0 0 1 1fffff00000000 Link: http://lkml.kernel.org/r/20180316143855.29838-1-neelx@redhat.com Fixes: b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible") Signed-off-by: Daniel Vacek <neelx@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-22lockdep: fix fs_reclaim warningTetsuo Handa
Dave Jones reported fs_reclaim lockdep warnings. ============================================ WARNING: possible recursive locking detected 4.15.0-rc9-backup-debug+ #1 Not tainted -------------------------------------------- sshd/24800 is trying to acquire lock: (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30 but task is already holding lock: (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(fs_reclaim); lock(fs_reclaim); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by sshd/24800: #0: (sk_lock-AF_INET6){+.+.}, at: [<000000001a069652>] tcp_sendmsg+0x19/0x40 #1: (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30 stack backtrace: CPU: 3 PID: 24800 Comm: sshd Not tainted 4.15.0-rc9-backup-debug+ #1 Call Trace: dump_stack+0xbc/0x13f __lock_acquire+0xa09/0x2040 lock_acquire+0x12e/0x350 fs_reclaim_acquire.part.102+0x29/0x30 kmem_cache_alloc+0x3d/0x2c0 alloc_extent_state+0xa7/0x410 __clear_extent_bit+0x3ea/0x570 try_release_extent_mapping+0x21a/0x260 __btrfs_releasepage+0xb0/0x1c0 btrfs_releasepage+0x161/0x170 try_to_release_page+0x162/0x1c0 shrink_page_list+0x1d5a/0x2fb0 shrink_inactive_list+0x451/0x940 shrink_node_memcg.constprop.88+0x4c9/0x5e0 shrink_node+0x12d/0x260 try_to_free_pages+0x418/0xaf0 __alloc_pages_slowpath+0x976/0x1790 __alloc_pages_nodemask+0x52c/0x5c0 new_slab+0x374/0x3f0 ___slab_alloc.constprop.81+0x47e/0x5a0 __slab_alloc.constprop.80+0x32/0x60 __kmalloc_track_caller+0x267/0x310 __kmalloc_reserve.isra.40+0x29/0x80 __alloc_skb+0xee/0x390 sk_stream_alloc_skb+0xb8/0x340 tcp_sendmsg_locked+0x8e6/0x1d30 tcp_sendmsg+0x27/0x40 inet_sendmsg+0xd0/0x310 sock_write_iter+0x17a/0x240 __vfs_write+0x2ab/0x380 vfs_write+0xfb/0x260 SyS_write+0xb6/0x140 do_syscall_64+0x1e5/0xc05 entry_SYSCALL64_slow_path+0x25/0x25 This warning is caused by commit d92a8cfcb37e ("locking/lockdep: Rework FS_RECLAIM annotation") which replaced the use of lockdep_{set,clear}_current_reclaim_state() in __perform_reclaim() and lockdep_trace_alloc() in slab_pre_alloc_hook() with fs_reclaim_acquire()/ fs_reclaim_release(). Since __kmalloc_reserve() from __alloc_skb() adds __GFP_NOMEMALLOC | __GFP_NOWARN to gfp_mask, and all reclaim path simply propagates __GFP_NOMEMALLOC, fs_reclaim_acquire() in slab_pre_alloc_hook() is trying to grab the 'fake' lock again when __perform_reclaim() already grabbed the 'fake' lock. The /* this guy won't enter reclaim */ if ((current->flags & PF_MEMALLOC) && !(gfp_mask & __GFP_NOMEMALLOC)) return false; test which causes slab_pre_alloc_hook() to try to grab the 'fake' lock was added by commit cf40bd16fdad ("lockdep: annotate reclaim context (__GFP_NOFS)"). But that test is outdated because PF_MEMALLOC thread won't enter reclaim regardless of __GFP_NOMEMALLOC after commit 341ce06f69ab ("page allocator: calculate the alloc_flags for allocation only once") added the PF_MEMALLOC safeguard ( /* Avoid recursion of direct reclaim */ if (p->flags & PF_MEMALLOC) goto nopage; in __alloc_pages_slowpath()). Thus, let's fix outdated test by removing __GFP_NOMEMALLOC test and allow __need_fs_reclaim() to return false. Link: http://lkml.kernel.org/r/201802280650.FJC73911.FOSOMLJVFFQtHO@I-love.SAKURA.ne.jp Fixes: d92a8cfcb37ecd13 ("locking/lockdep: Rework FS_RECLAIM annotation") Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: Dave Jones <davej@codemonkey.org.uk> Tested-by: Dave Jones <davej@codemonkey.org.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Nick Piggin <npiggin@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Nikolay Borisov <nborisov@suse.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: <stable@vger.kernel.org> [4.14+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>