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2017-11-15Merge tag 'drm-for-v4.15' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds
Pull drm updates from Dave Airlie: "This is the main drm pull request for v4.15. Core: - Atomic object lifetime fixes - Atomic iterator improvements - Sparse/smatch fixes - Legacy kms ioctls to be interruptible - EDID override improvements - fb/gem helper cleanups - Simple outreachy patches - Documentation improvements - Fix dma-buf rcu races - DRM mode object leasing for improving VR use cases. - vgaarb improvements for non-x86 platforms. New driver: - tve200: Faraday Technology TVE200 block. This "TV Encoder" encodes a ITU-T BT.656 stream and can be found in the StorLink SL3516 (later Cortina Systems CS3516) as well as the Grain Media GM8180. New bridges: - SiI9234 support New panels: - S6E63J0X03, OTM8009A, Seiko 43WVF1G, 7" rpi touch panel, Toshiba LT089AC19000, Innolux AT043TN24 i915: - Remove Coffeelake from alpha support - Cannonlake workarounds - Infoframe refactoring for DisplayPort - VBT updates - DisplayPort vswing/emph/buffer translation refactoring - CCS fixes - Restore GPU clock boost on missed vblanks - Scatter list updates for userptr allocations - Gen9+ transition watermarks - Display IPC (Isochronous Priority Control) - Private PAT management - GVT: improved error handling and pci config sanitizing - Execlist refactoring - Transparent Huge Page support - User defined priorities support - HuC/GuC firmware refactoring - DP MST fixes - eDP power sequencing fixes - Use RCU instead of stop_machine - PSR state tracking support - Eviction fixes - BDW DP aux channel timeout fixes - LSPCON fixes - Cannonlake PLL fixes amdgpu: - Per VM BO support - Powerplay cleanups - CI powerplay support - PASID mgr for kfd - SR-IOV fixes - initial GPU reset for vega10 - Prime mmap support - TTM updates - Clock query interface for Raven - Fence to handle ioctl - UVD encode ring support on Polaris - Transparent huge page DMA support - Compute LRU pipe tweaks - BO flag to allow buffers to opt out of implicit sync - CTX priority setting API - VRAM lost infrastructure plumbing qxl: - fix flicker since atomic rework amdkfd: - Further improvements from internal AMD tree - Usermode events - Drop radeon support nouveau: - Pascal temperature sensor support - Improved BAR2 handling - MMU rework to support Pascal MMU exynos: - Improved HDMI/mixer support - HDMI audio interface support tegra: - Prep work for tegra186 - Cleanup/fixes msm: - Preemption support for a5xx - Display fixes for 8x96 (snapdragon 820) - Async cursor plane fixes - FW loading rework - GPU debugging improvements vc4: - Prep for DSI panels - fix T-format tiling scanout - New madvise ioctl Rockchip: - LVDS support omapdrm: - omap4 HDMI CEC support etnaviv: - GPU performance counters groundwork sun4i: - refactor driver load + TCON backend - HDMI improvements - A31 support - Misc fixes udl: - Probe/EDID read fixes. tilcdc: - Misc fixes. pl111: - Support more variants adv7511: - Improve EDID handling. - HDMI CEC support sii8620: - Add remote control support" * tag 'drm-for-v4.15' of git://people.freedesktop.org/~airlied/linux: (1480 commits) drm/rockchip: analogix_dp: Use mutex rather than spinlock drm/mode_object: fix documentation for object lookups. drm/i915: Reorder context-close to avoid calling i915_vma_close() under RCU drm/i915: Move init_clock_gating() back to where it was drm/i915: Prune the reservation shared fence array drm/i915: Idle the GPU before shinking everything drm/i915: Lock llist_del_first() vs llist_del_all() drm/i915: Calculate ironlake intermediate watermarks correctly, v2. drm/i915: Disable lazy PPGTT page table optimization for vGPU drm/i915/execlists: Remove the priority "optimisation" drm/i915: Filter out spurious execlists context-switch interrupts drm/amdgpu: use irq-safe lock for kiq->ring_lock drm/amdgpu: bypass lru touch for KIQ ring submission drm/amdgpu: Potential uninitialized variable in amdgpu_vm_update_directories() drm/amdgpu: potential uninitialized variable in amdgpu_vce_ring_parse_cs() drm/amd/powerplay: initialize a variable before using it drm/amd/powerplay: suppress KASAN out of bounds warning in vega10_populate_all_memory_levels drm/amd/amdgpu: fix evicted VRAM bo adjudgement condition drm/vblank: Tune drm_crtc_accurate_vblank_count() WARN down to a debug drm/rockchip: add CONFIG_OF dependency for lvds ...
2017-11-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - a few misc bits - ocfs2 updates - almost all of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits) memory hotplug: fix comments when adding section mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP mm: simplify nodemask printing mm,oom_reaper: remove pointless kthread_run() error check mm/page_ext.c: check if page_ext is not prepared writeback: remove unused function parameter mm: do not rely on preempt_count in print_vma_addr mm, sparse: do not swamp log with huge vmemmap allocation failures mm/hmm: remove redundant variable align_end mm/list_lru.c: mark expected switch fall-through mm/shmem.c: mark expected switch fall-through mm/page_alloc.c: broken deferred calculation mm: don't warn about allocations which stall for too long fs: fuse: account fuse_inode slab memory as reclaimable mm, page_alloc: fix potential false positive in __zone_watermark_ok mm: mlock: remove lru_add_drain_all() mm, sysctl: make NUMA stats configurable shmem: convert shmem_init_inodecache() to void Unify migrate_pages and move_pages access checks mm, pagevec: rename pagevec drained field ...
2017-11-15memory hotplug: fix comments when adding sectionFan Du
Here, pfn_to_node should be page_to_nid. Link: http://lkml.kernel.org/r/1510735205-22540-1-git-send-email-fan.du@intel.com Signed-off-by: Fan Du <fan.du@intel.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>
2017-11-15mm: make alloc_node_mem_map a void call if we don't have ↵Oscar Salvador
CONFIG_FLAT_NODE_MEM_MAP free_area_init_node() calls alloc_node_mem_map(), but this function does nothing unless we have CONFIG_FLAT_NODE_MEM_MAP. As a cleanup, we can move the "#ifdef CONFIG_FLAT_NODE_MEM_MAP" within alloc_node_mem_map() out of the function, and define a alloc_node_mem_map() { } when CONFIG_FLAT_NODE_MEM_MAP is not present. This also moves the printk that lays within the "#ifdef CONFIG_FLAT_NODE_MEM_MAP" block from free_area_init_node() to alloc_node_mem_map(), getting rid of the "#ifdef CONFIG_FLAT_NODE_MEM_MAP" in free_area_init_node(). [akpm@linux-foundation.org: clean up the printk while we're there] Link: http://lkml.kernel.org/r/20171114111935.GA11758@techadventures.net Signed-off-by: Oscar Salvador <osalvador@techadventures.net> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: simplify nodemask printingMichal Hocko
alloc_warn() and dump_header() have to explicitly handle NULL nodemask which forces both paths to use pr_cont. We can do better. printk already handles NULL pointers properly so all we need is to teach nodemask_pr_args to handle NULL nodemask carefully. This allows simplification of both alloc_warn() and dump_header() and gets rid of pr_cont altogether. This patch has been motivated by patch from Joe Perches http://lkml.kernel.org/r/b31236dfe3fc924054fd7842bde678e71d193638.1509991345.git.joe@perches.com [akpm@linux-foundation.org: fix tile warning, per Arnd] Link: http://lkml.kernel.org/r/20171109100531.3cn2hcqnuj7mjaju@dhcp22.suse.cz Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Joe Perches <joe@perches.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm,oom_reaper: remove pointless kthread_run() error checkTetsuo Handa
Since oom_init() is called before userspace processes start, memory allocation failure for creating the OOM reaper kernel thread will let the OOM killer call panic() rather than wake up the OOM reaper. Link: http://lkml.kernel.org/r/1510137800-4602-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> 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>
2017-11-15mm/page_ext.c: check if page_ext is not preparedJaewon Kim
online_page_ext() and page_ext_init() allocate page_ext for each section, but they do not allocate if the first PFN is !pfn_present(pfn) or !pfn_valid(pfn). Then section->page_ext remains as NULL. lookup_page_ext checks NULL only if CONFIG_DEBUG_VM is enabled. For a valid PFN, __set_page_owner will try to get page_ext through lookup_page_ext. Without CONFIG_DEBUG_VM lookup_page_ext will misuse NULL pointer as value 0. This incurrs invalid address access. This is the panic example when PFN 0x100000 is not valid but PFN 0x13FC00 is being used for page_ext. section->page_ext is NULL, get_entry returned invalid page_ext address as 0x1DFA000 for a PFN 0x13FC00. To avoid this panic, CONFIG_DEBUG_VM should be removed so that page_ext will be checked at all times. Unable to handle kernel paging request at virtual address 01dfa014 ------------[ cut here ]------------ Kernel BUG at ffffff80082371e0 [verbose debug info unavailable] Internal error: Oops: 96000045 [#1] PREEMPT SMP Modules linked in: PC is at __set_page_owner+0x48/0x78 LR is at __set_page_owner+0x44/0x78 __set_page_owner+0x48/0x78 get_page_from_freelist+0x880/0x8e8 __alloc_pages_nodemask+0x14c/0xc48 __do_page_cache_readahead+0xdc/0x264 filemap_fault+0x2ac/0x550 ext4_filemap_fault+0x3c/0x58 __do_fault+0x80/0x120 handle_mm_fault+0x704/0xbb0 do_page_fault+0x2e8/0x394 do_mem_abort+0x88/0x124 Pre-4.7 kernels also need commit f86e4271978b ("mm: check the return value of lookup_page_ext for all call sites"). Link: http://lkml.kernel.org/r/20171107094131.14621-1-jaewon31.kim@samsung.com Fixes: eefa864b701d ("mm/page_ext: resurrect struct page extending code for debugging") Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Joonsoo Kim <js1304@gmail.com> Cc: <stable@vger.kernel.org> [depends on f86e427197, see above] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15writeback: remove unused function parameterWang Long
The parameter `struct bdi_writeback *wb` is not been used in the function body. Remove it. Link: http://lkml.kernel.org/r/1509685485-15278-1-git-send-email-wanglong19@meituan.com Signed-off-by: Wang Long <wanglong19@meituan.com> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: do not rely on preempt_count in print_vma_addrMichal Hocko
The preempt count check on print_vma_addr has been added by commit e8bff74afbdb ("x86: fix "BUG: sleeping function called from invalid context" in print_vma_addr()") and it relied on the elevated preempt count from preempt_conditional_sti because preempt_count check doesn't work on non preemptive kernels by default. The code has evolved though and commit d99e1bd175f4 ("x86/entry/traps: Refactor preemption and interrupt flag handling") has replaced preempt_conditional_sti by an explicit preempt_disable which is noop on !PREEMPT so the check in print_vma_addr is broken. Fix the issue by using trylock on mmap_sem rather than chacking the preempt count. The allocation we are relying on has to be GFP_NOWAIT as well. There is a chance that we won't dump the vma state if the lock is contended or the memory short but this is acceptable outcome and much less fragile than the not working preemption check or tricks around it. Link: http://lkml.kernel.org/r/20171106134031.g6dbelg55mrbyc6i@dhcp22.suse.cz Fixes: d99e1bd175f4 ("x86/entry/traps: Refactor preemption and interrupt flag handling") Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Yang Shi <yang.s@alibaba-inc.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm, sparse: do not swamp log with huge vmemmap allocation failuresMichal Hocko
While doing memory hotplug tests under heavy memory pressure we have noticed too many page allocation failures when allocating vmemmap memmap backed by huge page kworker/u3072:1: page allocation failure: order:9, mode:0x24084c0(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO) [...] Call Trace: dump_trace+0x59/0x310 show_stack_log_lvl+0xea/0x170 show_stack+0x21/0x40 dump_stack+0x5c/0x7c warn_alloc_failed+0xe2/0x150 __alloc_pages_nodemask+0x3ed/0xb20 alloc_pages_current+0x7f/0x100 vmemmap_alloc_block+0x79/0xb6 __vmemmap_alloc_block_buf+0x136/0x145 vmemmap_populate+0xd2/0x2b9 sparse_mem_map_populate+0x23/0x30 sparse_add_one_section+0x68/0x18e __add_pages+0x10a/0x1d0 arch_add_memory+0x4a/0xc0 add_memory_resource+0x89/0x160 add_memory+0x6d/0xd0 acpi_memory_device_add+0x181/0x251 acpi_bus_attach+0xfd/0x19b acpi_bus_scan+0x59/0x69 acpi_device_hotplug+0xd2/0x41f acpi_hotplug_work_fn+0x1a/0x23 process_one_work+0x14e/0x410 worker_thread+0x116/0x490 kthread+0xbd/0xe0 ret_from_fork+0x3f/0x70 and we do see many of those because essentially every allocation fails for each memory section. This is an excessive way to tell the user that there is nothing to really worry about because we do have a fallback mechanism to use base pages. The only downside might be a performance degradation due to TLB pressure. This patch changes vmemmap_alloc_block() to use __GFP_NOWARN and warn explicitly once on the first allocation failure. This will reduce the noise in the kernel log considerably, while we still have an indication that a performance might be impacted. [mhocko@kernel.org: forgot to git add the follow up fix] Link: http://lkml.kernel.org/r/20171107090635.c27thtse2lchjgvb@dhcp22.suse.cz Link: http://lkml.kernel.org/r/20171106092228.31098-1-mhocko@kernel.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Joe Perches <joe@perches.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Khalid Aziz <khalid.aziz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/hmm: remove redundant variable align_endColin Ian King
Variable align_end is assigned a value but it is never read, so the variable is redundant and can be removed. Cleans up the clang warning: Value stored to 'align_end' is never read Link: http://lkml.kernel.org/r/20171017143837.23207-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/list_lru.c: mark expected switch fall-throughGustavo A. R. Silva
In preparation for enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Link: http://lkml.kernel.org/r/20171020190754.GA24332@embeddedor.com Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/shmem.c: mark expected switch fall-throughGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Link: http://lkml.kernel.org/r/20171020191058.GA24427@embeddedor.com Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/page_alloc.c: broken deferred calculationPavel Tatashin
In reset_deferred_meminit() we determine number of pages that must not be deferred. We initialize pages for at least 2G of memory, but also pages for reserved memory in this node. The reserved memory is determined in this function: memblock_reserved_memory_within(), which operates over physical addresses, and returns size in bytes. However, reset_deferred_meminit() assumes that that this function operates with pfns, and returns page count. The result is that in the best case machine boots slower than expected due to initializing more pages than needed in single thread, and in the worst case panics because fewer than needed pages are initialized early. Link: http://lkml.kernel.org/r/20171021011707.15191-1-pasha.tatashin@oracle.com Fixes: 864b9a393dcb ("mm: consider memblock reservations for deferred memory initialization sizing") Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: don't warn about allocations which stall for too longTetsuo Handa
Commit 63f53dea0c98 ("mm: warn about allocations which stall for too long") was a great step for reducing possibility of silent hang up problem caused by memory allocation stalls. But this commit reverts it, for it is possible to trigger OOM lockup and/or soft lockups when many threads concurrently called warn_alloc() (in order to warn about memory allocation stalls) due to current implementation of printk(), and it is difficult to obtain useful information due to limitation of synchronous warning approach. Current printk() implementation flushes all pending logs using the context of a thread which called console_unlock(). printk() should be able to flush all pending logs eventually unless somebody continues appending to printk() buffer. Since warn_alloc() started appending to printk() buffer while waiting for oom_kill_process() to make forward progress when oom_kill_process() is processing pending logs, it became possible for warn_alloc() to force oom_kill_process() loop inside printk(). As a result, warn_alloc() significantly increased possibility of preventing oom_kill_process() from making forward progress. ---------- Pseudo code start ---------- Before warn_alloc() was introduced: retry: if (mutex_trylock(&oom_lock)) { while (atomic_read(&printk_pending_logs) > 0) { atomic_dec(&printk_pending_logs); print_one_log(); } // Send SIGKILL here. mutex_unlock(&oom_lock) } goto retry; After warn_alloc() was introduced: retry: if (mutex_trylock(&oom_lock)) { while (atomic_read(&printk_pending_logs) > 0) { atomic_dec(&printk_pending_logs); print_one_log(); } // Send SIGKILL here. mutex_unlock(&oom_lock) } else if (waited_for_10seconds()) { atomic_inc(&printk_pending_logs); } goto retry; ---------- Pseudo code end ---------- Although waited_for_10seconds() becomes true once per 10 seconds, unbounded number of threads can call waited_for_10seconds() at the same time. Also, since threads doing waited_for_10seconds() keep doing almost busy loop, the thread doing print_one_log() can use little CPU resource. Therefore, this situation can be simplified like ---------- Pseudo code start ---------- retry: if (mutex_trylock(&oom_lock)) { while (atomic_read(&printk_pending_logs) > 0) { atomic_dec(&printk_pending_logs); print_one_log(); } // Send SIGKILL here. mutex_unlock(&oom_lock) } else { atomic_inc(&printk_pending_logs); } goto retry; ---------- Pseudo code end ---------- when printk() is called faster than print_one_log() can process a log. One of possible mitigation would be to introduce a new lock in order to make sure that no other series of printk() (either oom_kill_process() or warn_alloc()) can append to printk() buffer when one series of printk() (either oom_kill_process() or warn_alloc()) is already in progress. Such serialization will also help obtaining kernel messages in readable form. ---------- Pseudo code start ---------- retry: if (mutex_trylock(&oom_lock)) { mutex_lock(&oom_printk_lock); while (atomic_read(&printk_pending_logs) > 0) { atomic_dec(&printk_pending_logs); print_one_log(); } // Send SIGKILL here. mutex_unlock(&oom_printk_lock); mutex_unlock(&oom_lock) } else { if (mutex_trylock(&oom_printk_lock)) { atomic_inc(&printk_pending_logs); mutex_unlock(&oom_printk_lock); } } goto retry; ---------- Pseudo code end ---------- But this commit does not go that direction, for we don't want to introduce a new lock dependency, and we unlikely be able to obtain useful information even if we serialized oom_kill_process() and warn_alloc(). Synchronous approach is prone to unexpected results (e.g. too late [1], too frequent [2], overlooked [3]). As far as I know, warn_alloc() never helped with providing information other than "something is going wrong". I want to consider asynchronous approach which can obtain information during stalls with possibly relevant threads (e.g. the owner of oom_lock and kswapd-like threads) and serve as a trigger for actions (e.g. turn on/off tracepoints, ask libvirt daemon to take a memory dump of stalling KVM guest for diagnostic purpose). This commit temporarily loses ability to report e.g. OOM lockup due to unable to invoke the OOM killer due to !__GFP_FS allocation request. But asynchronous approach will be able to detect such situation and emit warning. Thus, let's remove warn_alloc(). [1] https://bugzilla.kernel.org/show_bug.cgi?id=192981 [2] http://lkml.kernel.org/r/CAM_iQpWuPVGc2ky8M-9yukECtS+zKjiDasNymX7rMcBjBFyM_A@mail.gmail.com [3] commit db73ee0d46379922 ("mm, vmscan: do not loop on too_many_isolated for ever")) Link: http://lkml.kernel.org/r/1509017339-4802-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: Cong Wang <xiyou.wangcong@gmail.com> Reported-by: yuwang.yuwang <yuwang.yuwang@alibaba-inc.com> Reported-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm, page_alloc: fix potential false positive in __zone_watermark_okVlastimil Babka
Since commit 97a16fc82a7c ("mm, page_alloc: only enforce watermarks for order-0 allocations"), __zone_watermark_ok() check for high-order allocations will shortcut per-migratetype free list checks for ALLOC_HARDER allocations, and return true as long as there's free page of any migratetype. The intention is that ALLOC_HARDER can allocate from MIGRATE_HIGHATOMIC free lists, while normal allocations can't. However, as a side effect, the watermark check will then also return true when there are pages only on the MIGRATE_ISOLATE list, or (prior to CMA conversion to ZONE_MOVABLE) on the MIGRATE_CMA list. Since the allocation cannot actually obtain isolated pages, and might not be able to obtain CMA pages, this can result in a false positive. The condition should be rare and perhaps the outcome is not a fatal one. Still, it's better if the watermark check is correct. There also shouldn't be a performance tradeoff here. Link: http://lkml.kernel.org/r/20171102125001.23708-1-vbabka@suse.cz Fixes: 97a16fc82a7c ("mm, page_alloc: only enforce watermarks for order-0 allocations") Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Rik van Riel <riel@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: mlock: remove lru_add_drain_all()Shakeel Butt
lru_add_drain_all() is not required by mlock() and it will drain everything that has been cached at the time mlock is called. And that is not really related to the memory which will be faulted in (and cached) and mlocked by the syscall itself. If anything lru_add_drain_all() should be called _after_ pages have been mlocked and faulted in but even that is not strictly needed because those pages would get to the appropriate LRUs lazily during the reclaim path. Moreover follow_page_pte (gup) will drain the local pcp LRU cache. On larger machines the overhead of lru_add_drain_all() in mlock() can be significant when mlocking data already in memory. We have observed high latency in mlock() due to lru_add_drain_all() when the users were mlocking in memory tmpfs files. [mhocko@suse.com: changelog fix] Link: http://lkml.kernel.org/r/20171019222507.2894-1-shakeelb@google.com Signed-off-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Yisheng Xie <xieyisheng1@huawei.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Greg Thelen <gthelen@google.com> Cc: Hugh Dickins <hughd@google.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>
2017-11-15mm, sysctl: make NUMA stats configurableKemi Wang
This is the second step which introduces a tunable interface that allow numa stats configurable for optimizing zone_statistics(), as suggested by Dave Hansen and Ying Huang. ========================================================================= When page allocation performance becomes a bottleneck and you can tolerate some possible tool breakage and decreased numa counter precision, you can do: echo 0 > /proc/sys/vm/numa_stat In this case, numa counter update is ignored. We can see about *4.8%*(185->176) drop of cpu cycles per single page allocation and reclaim on Jesper's page_bench01 (single thread) and *8.1%*(343->315) drop of cpu cycles per single page allocation and reclaim on Jesper's page_bench03 (88 threads) running on a 2-Socket Broadwell-based server (88 threads, 126G memory). Benchmark link provided by Jesper D Brouer (increase loop times to 10000000): https://github.com/netoptimizer/prototype-kernel/tree/master/kernel/mm/bench ========================================================================= When page allocation performance is not a bottleneck and you want all tooling to work, you can do: echo 1 > /proc/sys/vm/numa_stat This is system default setting. Many thanks to Michal Hocko, Dave Hansen, Ying Huang and Vlastimil Babka for comments to help improve the original patch. [keescook@chromium.org: make sure mutex is a global static] Link: http://lkml.kernel.org/r/20171107213809.GA4314@beast Link: http://lkml.kernel.org/r/1508290927-8518-1-git-send-email-kemi.wang@intel.com Signed-off-by: Kemi Wang <kemi.wang@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reported-by: Jesper Dangaard Brouer <brouer@redhat.com> Suggested-by: Dave Hansen <dave.hansen@intel.com> Suggested-by: Ying Huang <ying.huang@intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: "Luis R . Rodriguez" <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Christopher Lameter <cl@linux.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Tim Chen <tim.c.chen@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15shmem: convert shmem_init_inodecache() to voidweiping zhang
shmem_inode_cachep was created with SLAB_PANIC flag and shmem_init_inodecache() never returns non-zero, so convert this function to return void. Link: http://lkml.kernel.org/r/20170909124542.GA35224@bogon.didichuxing.com Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15Unify migrate_pages and move_pages access checksOtto Ebeling
Commit 197e7e521384 ("Sanitize 'move_pages()' permission checks") fixed a security issue I reported in the move_pages syscall, and made it so that you can't act on set-uid processes unless you have the CAP_SYS_PTRACE capability. Unify the access check logic of migrate_pages to match the new behavior of move_pages. We discussed this a bit in the security@ list and thought it'd be good for consistency even though there's no evident security impact. The NUMA node access checks are left intact and require CAP_SYS_NICE as before. Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1710011830320.6333@lakka.kapsi.fi Signed-off-by: Otto Ebeling <otto.ebeling@iki.fi> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm, pagevec: rename pagevec drained fieldMel Gorman
According to Vlastimil Babka, the drained field in pagevec is potentially misleading because it might be interpreted as draining this pagevec instead of the percpu lru pagevecs. Rename the field for clarity. Link: http://lkml.kernel.org/r/20171019093346.ylahzdpzmoriyf4v@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@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>
2017-11-15mm, page_alloc: simplify list handling in rmqueue_bulk()Vlastimil Babka
rmqueue_bulk() fills an empty pcplist with pages from the free list. It tries to preserve increasing order by pfn to the caller, because it leads to better performance with some I/O controllers, as explained in commit e084b2d95e48 ("page-allocator: preserve PFN ordering when __GFP_COLD is set"). To preserve the order, it's sufficient to add pages to the tail of the list as they are retrieved. The current code instead adds to the head of the list, but then updates the list head pointer to the last added page, in each step. This does result in the same order, but is needlessly confusing and potentially wasteful, with no apparent benefit. This patch simplifies the code and adjusts comment accordingly. Link: http://lkml.kernel.org/r/f6505442-98a9-12e4-b2cd-0fa83874c159@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@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>
2017-11-15mm: remove __GFP_COLDMel Gorman
As the page free path makes no distinction between cache hot and cold pages, there is no real useful ordering of pages in the free list that allocation requests can take advantage of. Juding from the users of __GFP_COLD, it is likely that a number of them are the result of copying other sites instead of actually measuring the impact. Remove the __GFP_COLD parameter which simplifies a number of paths in the page allocator. This is potentially controversial but bear in mind that the size of the per-cpu pagelists versus modern cache sizes means that the whole per-cpu list can often fit in the L3 cache. Hence, there is only a potential benefit for microbenchmarks that alloc/free pages in a tight loop. It's even worse when THP is taken into account which has little or no chance of getting a cache-hot page as the per-cpu list is bypassed and the zeroing of multiple pages will thrash the cache anyway. The truncate microbenchmarks are not shown as this patch affects the allocation path and not the free path. A page fault microbenchmark was tested but it showed no sigificant difference which is not surprising given that the __GFP_COLD branches are a miniscule percentage of the fault path. Link: http://lkml.kernel.org/r/20171018075952.10627-9-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@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>
2017-11-15mm: remove cold parameter from free_hot_cold_page*Mel Gorman
Most callers users of free_hot_cold_page claim the pages being released are cache hot. The exception is the page reclaim paths where it is likely that enough pages will be freed in the near future that the per-cpu lists are going to be recycled and the cache hotness information is lost. As no one really cares about the hotness of pages being released to the allocator, just ditch the parameter. The APIs are renamed to indicate that it's no longer about hot/cold pages. It should also be less confusing as there are subtle differences between them. __free_pages drops a reference and frees a page when the refcount reaches zero. free_hot_cold_page handled pages whose refcount was already zero which is non-obvious from the name. free_unref_page should be more obvious. No performance impact is expected as the overhead is marginal. The parameter is removed simply because it is a bit stupid to have a useless parameter copied everywhere. [mgorman@techsingularity.net: add pages to head, not tail] Link: http://lkml.kernel.org/r/20171019154321.qtpzaeftoyyw4iey@techsingularity.net Link: http://lkml.kernel.org/r/20171018075952.10627-8-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@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>
2017-11-15mm: remove cold parameter for release_pagesMel Gorman
All callers of release_pages claim the pages being released are cache hot. As no one cares about the hotness of pages being released to the allocator, just ditch the parameter. No performance impact is expected as the overhead is marginal. The parameter is removed simply because it is a bit stupid to have a useless parameter copied everywhere. Link: http://lkml.kernel.org/r/20171018075952.10627-7-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@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>
2017-11-15mm, pagevec: remove cold parameter for pagevecsMel Gorman
Every pagevec_init user claims the pages being released are hot even in cases where it is unlikely the pages are hot. As no one cares about the hotness of pages being released to the allocator, just ditch the parameter. No performance impact is expected as the overhead is marginal. The parameter is removed simply because it is a bit stupid to have a useless parameter copied everywhere. Link: http://lkml.kernel.org/r/20171018075952.10627-6-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@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>
2017-11-15mm: only drain per-cpu pagevecs once per pagevec usageMel Gorman
When a pagevec is initialised on the stack, it is generally used multiple times over a range of pages, looking up entries and then releasing them. On each pagevec_release, the per-cpu deferred LRU pagevecs are drained on the grounds the page being released may be on those queues and the pages may be cache hot. In many cases only the first drain is necessary as it's unlikely that the range of pages being walked is racing against LRU addition. Even if there is such a race, the impact is marginal where as constantly redraining the lru pagevecs costs. This patch ensures that pagevec is only drained once in a given lifecycle without increasing the cache footprint of the pagevec structure. Only sparsetruncate tiny is shown here as large files have many exceptional entries and calls pagecache_release less frequently. sparsetruncate (tiny) 4.14.0-rc4 4.14.0-rc4 batchshadow-v1r1 onedrain-v1r1 Min Time 141.00 ( 0.00%) 141.00 ( 0.00%) 1st-qrtle Time 142.00 ( 0.00%) 142.00 ( 0.00%) 2nd-qrtle Time 142.00 ( 0.00%) 142.00 ( 0.00%) 3rd-qrtle Time 143.00 ( 0.00%) 143.00 ( 0.00%) Max-90% Time 144.00 ( 0.00%) 144.00 ( 0.00%) Max-95% Time 146.00 ( 0.00%) 145.00 ( 0.68%) Max-99% Time 198.00 ( 0.00%) 194.00 ( 2.02%) Max Time 254.00 ( 0.00%) 208.00 ( 18.11%) Amean Time 145.12 ( 0.00%) 144.30 ( 0.56%) Stddev Time 12.74 ( 0.00%) 9.62 ( 24.49%) Coeff Time 8.78 ( 0.00%) 6.67 ( 24.06%) Best99%Amean Time 144.29 ( 0.00%) 143.82 ( 0.32%) Best95%Amean Time 142.68 ( 0.00%) 142.31 ( 0.26%) Best90%Amean Time 142.52 ( 0.00%) 142.19 ( 0.24%) Best75%Amean Time 142.26 ( 0.00%) 141.98 ( 0.20%) Best50%Amean Time 141.90 ( 0.00%) 141.71 ( 0.13%) Best25%Amean Time 141.80 ( 0.00%) 141.43 ( 0.26%) The impact on bonnie is marginal and within the noise because a significant percentage of the file being truncated has been reclaimed and consists of shadow entries which reduce the hotness of the pagevec_release path. Link: http://lkml.kernel.org/r/20171018075952.10627-5-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm, truncate: remove all exceptional entries from pagevec under one lockMel Gorman
During truncate each entry in a pagevec is checked to see if it is an exceptional entry and if so, the shadow entry is cleaned up. This is potentially expensive as multiple entries for a mapping locks/unlocks the tree lock. This batches the operation such that any exceptional entries removed from a pagevec only acquire the mapping tree lock once. The corner case where this is more expensive is where there is only one exceptional entry but this is unlikely due to temporal locality and how it affects LRU ordering. Note that for truncations of small files created recently, this patch should show no gain because it only batches the handling of exceptional entries. sparsetruncate (large) 4.14.0-rc4 4.14.0-rc4 pickhelper-v1r1 batchshadow-v1r1 Min Time 38.00 ( 0.00%) 27.00 ( 28.95%) 1st-qrtle Time 40.00 ( 0.00%) 28.00 ( 30.00%) 2nd-qrtle Time 44.00 ( 0.00%) 41.00 ( 6.82%) 3rd-qrtle Time 146.00 ( 0.00%) 147.00 ( -0.68%) Max-90% Time 153.00 ( 0.00%) 153.00 ( 0.00%) Max-95% Time 155.00 ( 0.00%) 156.00 ( -0.65%) Max-99% Time 181.00 ( 0.00%) 171.00 ( 5.52%) Amean Time 93.04 ( 0.00%) 88.43 ( 4.96%) Best99%Amean Time 92.08 ( 0.00%) 86.13 ( 6.46%) Best95%Amean Time 89.19 ( 0.00%) 83.13 ( 6.80%) Best90%Amean Time 85.60 ( 0.00%) 79.15 ( 7.53%) Best75%Amean Time 72.95 ( 0.00%) 65.09 ( 10.78%) Best50%Amean Time 39.86 ( 0.00%) 28.20 ( 29.25%) Best25%Amean Time 39.44 ( 0.00%) 27.70 ( 29.77%) bonnie 4.14.0-rc4 4.14.0-rc4 pickhelper-v1r1 batchshadow-v1r1 Hmean SeqCreate ops 71.92 ( 0.00%) 76.78 ( 6.76%) Hmean SeqCreate read 42.42 ( 0.00%) 45.01 ( 6.10%) Hmean SeqCreate del 26519.88 ( 0.00%) 27191.87 ( 2.53%) Hmean RandCreate ops 71.92 ( 0.00%) 76.95 ( 7.00%) Hmean RandCreate read 44.44 ( 0.00%) 49.23 ( 10.78%) Hmean RandCreate del 24948.62 ( 0.00%) 24764.97 ( -0.74%) Truncation of a large number of files shows a substantial gain with 99% of files being truncated 6.46% faster. bonnie shows a modest gain of 2.53% [jack@suse.cz: fix truncate_exceptional_pvec_entries()] Link: http://lkml.kernel.org/r/20171108164226.26788-1-jack@suse.cz Link: http://lkml.kernel.org/r/20171018075952.10627-4-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@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>
2017-11-15mm, truncate: do not check mapping for every page being truncatedMel Gorman
During truncation, the mapping has already been checked for shmem and dax so it's known that workingset_update_node is required. This patch avoids the checks on mapping for each page being truncated. In all other cases, a lookup helper is used to determine if workingset_update_node() needs to be called. The one danger is that the API is slightly harder to use as calling workingset_update_node directly without checking for dax or shmem mappings could lead to surprises. However, the API rarely needs to be used and hopefully the comment is enough to give people the hint. sparsetruncate (tiny) 4.14.0-rc4 4.14.0-rc4 oneirq-v1r1 pickhelper-v1r1 Min Time 141.00 ( 0.00%) 140.00 ( 0.71%) 1st-qrtle Time 142.00 ( 0.00%) 141.00 ( 0.70%) 2nd-qrtle Time 142.00 ( 0.00%) 142.00 ( 0.00%) 3rd-qrtle Time 143.00 ( 0.00%) 143.00 ( 0.00%) Max-90% Time 144.00 ( 0.00%) 144.00 ( 0.00%) Max-95% Time 147.00 ( 0.00%) 145.00 ( 1.36%) Max-99% Time 195.00 ( 0.00%) 191.00 ( 2.05%) Max Time 230.00 ( 0.00%) 205.00 ( 10.87%) Amean Time 144.37 ( 0.00%) 143.82 ( 0.38%) Stddev Time 10.44 ( 0.00%) 9.00 ( 13.74%) Coeff Time 7.23 ( 0.00%) 6.26 ( 13.41%) Best99%Amean Time 143.72 ( 0.00%) 143.34 ( 0.26%) Best95%Amean Time 142.37 ( 0.00%) 142.00 ( 0.26%) Best90%Amean Time 142.19 ( 0.00%) 141.85 ( 0.24%) Best75%Amean Time 141.92 ( 0.00%) 141.58 ( 0.24%) Best50%Amean Time 141.69 ( 0.00%) 141.31 ( 0.27%) Best25%Amean Time 141.38 ( 0.00%) 140.97 ( 0.29%) As you'd expect, the gain is marginal but it can be detected. The differences in bonnie are all within the noise which is not surprising given the impact on the microbenchmark. radix_tree_update_node_t is a callback for some radix operations that optionally passes in a private field. The only user of the callback is workingset_update_node and as it no longer requires a mapping, the private field is removed. Link: http://lkml.kernel.org/r/20171018075952.10627-3-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@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>
2017-11-15mm, page_alloc: enable/disable IRQs once when freeing a list of pagesMel Gorman
Patch series "Follow-up for speed up page cache truncation", v2. This series is a follow-on for Jan Kara's series "Speed up page cache truncation" series. We both ended up looking at the same problem but saw different problems based on the same data. This series builds upon his work. A variety of workloads were compared on four separate machines but each machine showed gains albeit at different levels. Minimally, some of the differences are due to NUMA where truncating data from a remote node is slower than a local node. The workloads checked were o sparse truncate microbenchmark, tiny o sparse truncate microbenchmark, large o reaim-io disk workfile o dbench4 (modified by mmtests to produce more stable results) o filebench varmail configuration for small memory size o bonnie, directory operations, working set size 2*RAM reaim-io, dbench and filebench all showed minor gains. Truncation does not dominate those workloads but were tested to ensure no other regressions. They will not be reported further. The sparse truncate microbench was written by Jan. It creates a number of files and then times how long it takes to truncate each one. The "tiny" configuraiton creates a number of files that easily fits in memory and times how long it takes to truncate files with page cache. The large configuration uses enough files to have data that is twice the size of memory and so timings there include truncating page cache and working set shadow entries in the radix tree. Patches 1-4 are the most relevant parts of this series. Patches 5-8 are optional as they are deleting code that is essentially useless but has a negligible performance impact. The changelogs have more information on performance but just for bonnie delete options, the main comparison is bonnie 4.14.0-rc5 4.14.0-rc5 4.14.0-rc5 jan-v2 vanilla mel-v2 Hmean SeqCreate ops 76.20 ( 0.00%) 75.80 ( -0.53%) 76.80 ( 0.79%) Hmean SeqCreate read 85.00 ( 0.00%) 85.00 ( 0.00%) 85.00 ( 0.00%) Hmean SeqCreate del 13752.31 ( 0.00%) 12090.23 ( -12.09%) 15304.84 ( 11.29%) Hmean RandCreate ops 76.00 ( 0.00%) 75.60 ( -0.53%) 77.00 ( 1.32%) Hmean RandCreate read 96.80 ( 0.00%) 96.80 ( 0.00%) 97.00 ( 0.21%) Hmean RandCreate del 13233.75 ( 0.00%) 11525.35 ( -12.91%) 14446.61 ( 9.16%) Jan's series is the baseline and the vanilla kernel is 12% slower where as this series on top gains another 11%. This is from a different machine than the data in the changelogs but the detailed data was not collected as there was no substantial change in v2. This patch (of 8): Freeing a list of pages current enables/disables IRQs for each page freed. This patch splits freeing a list of pages into two operations -- preparing the pages for freeing and the actual freeing. This is a tradeoff - we're taking two passes of the list to free in exchange for avoiding multiple enable/disable of IRQs. sparsetruncate (tiny) 4.14.0-rc4 4.14.0-rc4 janbatch-v1r1 oneirq-v1r1 Min Time 149.00 ( 0.00%) 141.00 ( 5.37%) 1st-qrtle Time 150.00 ( 0.00%) 142.00 ( 5.33%) 2nd-qrtle Time 151.00 ( 0.00%) 142.00 ( 5.96%) 3rd-qrtle Time 151.00 ( 0.00%) 143.00 ( 5.30%) Max-90% Time 153.00 ( 0.00%) 144.00 ( 5.88%) Max-95% Time 155.00 ( 0.00%) 147.00 ( 5.16%) Max-99% Time 201.00 ( 0.00%) 195.00 ( 2.99%) Max Time 236.00 ( 0.00%) 230.00 ( 2.54%) Amean Time 152.65 ( 0.00%) 144.37 ( 5.43%) Stddev Time 9.78 ( 0.00%) 10.44 ( -6.72%) Coeff Time 6.41 ( 0.00%) 7.23 ( -12.84%) Best99%Amean Time 152.07 ( 0.00%) 143.72 ( 5.50%) Best95%Amean Time 150.75 ( 0.00%) 142.37 ( 5.56%) Best90%Amean Time 150.59 ( 0.00%) 142.19 ( 5.58%) Best75%Amean Time 150.36 ( 0.00%) 141.92 ( 5.61%) Best50%Amean Time 150.04 ( 0.00%) 141.69 ( 5.56%) Best25%Amean Time 149.85 ( 0.00%) 141.38 ( 5.65%) With a tiny number of files, each file truncated has resident page cache and it shows that time to truncate is roughtly 5-6% with some minor jitter. 4.14.0-rc4 4.14.0-rc4 janbatch-v1r1 oneirq-v1r1 Hmean SeqCreate ops 65.27 ( 0.00%) 81.86 ( 25.43%) Hmean SeqCreate read 39.48 ( 0.00%) 47.44 ( 20.16%) Hmean SeqCreate del 24963.95 ( 0.00%) 26319.99 ( 5.43%) Hmean RandCreate ops 65.47 ( 0.00%) 82.01 ( 25.26%) Hmean RandCreate read 42.04 ( 0.00%) 51.75 ( 23.09%) Hmean RandCreate del 23377.66 ( 0.00%) 23764.79 ( 1.66%) As expected, there is a small gain for the delete operation. [mgorman@techsingularity.net: use page_private and set_page_private helpers] Link: http://lkml.kernel.org/r/20171018101547.mjycw7zreb66jzpa@techsingularity.net Link: http://lkml.kernel.org/r/20171018075952.10627-2-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Cc: Jan Kara <jack@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Chinner <david@fromorbit.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>
2017-11-15mm: batch radix tree operations when truncating pagesJan Kara
Currently we remove pages from the radix tree one by one. To speed up page cache truncation, lock several pages at once and free them in one go. This allows us to batch radix tree operations in a more efficient way and also save round-trips on mapping->tree_lock. As a result we gain about 20% speed improvement in page cache truncation. Data from a simple benchmark timing 10000 truncates of 1024 pages (on ext4 on ramdisk but the filesystem is barely visible in the profiles). The range shows 1% and 95% percentiles of the measured times: 4.14-rc2 4.14-rc2 + batched truncation 248-256 209-219 249-258 209-217 248-255 211-239 248-255 209-217 247-256 210-218 [jack@suse.cz: convert delete_from_page_cache_batch() to pagevec] Link: http://lkml.kernel.org/r/20171018111648.13714-1-jack@suse.cz [akpm@linux-foundation.org: move struct pagevec forward declaration to top-of-file] Link: http://lkml.kernel.org/r/20171010151937.26984-8-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: factor out checks and accounting from __delete_from_page_cache()Jan Kara
Move checks and accounting updates from __delete_from_page_cache() into a separate function. We will reuse it when batching page cache truncation operations. Link: http://lkml.kernel.org/r/20171010151937.26984-7-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: move clearing of page->mapping to page_cache_tree_delete()Jan Kara
Clearing of page->mapping makes sense in page_cache_tree_delete() as well and it will help us with batching things this way. Link: http://lkml.kernel.org/r/20171010151937.26984-6-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: move accounting updates before page_cache_tree_delete()Jan Kara
Move updates of various counters before page_cache_tree_delete() call. It will be easier to batch things this way and there is no difference whether the counters get updated before or after removal from the radix tree. Link: http://lkml.kernel.org/r/20171010151937.26984-5-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: factor out page cache page freeing into a separate functionJan Kara
Factor out page freeing from delete_from_page_cache() into a separate function. We will need to call the same when batching pagecache deletion operations. invalidate_complete_page2() and replace_page_cache_page() might want to call this function as well however they currently don't seem to handle THPs so it's unnecessary for them to take the hit of checking whether a page is THP or not. Link: http://lkml.kernel.org/r/20171010151937.26984-4-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: refactor truncate_complete_page()Jan Kara
Move call of delete_from_page_cache() and page->mapping check out of truncate_complete_page() into the single caller - truncate_inode_page(). Also move page_mapped() check into truncate_complete_page(). That way it will be easier to batch operations. Also rename truncate_complete_page() to truncate_cleanup_page(). Link: http://lkml.kernel.org/r/20171010151937.26984-3-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm: speed up cancel_dirty_page() for clean pagesJan Kara
Patch series "Speed up page cache truncation", v1. When rebasing our enterprise distro to a newer kernel (from 4.4 to 4.12) we have noticed a regression in bonnie++ benchmark when deleting files. Eventually we have tracked this down to a fact that page cache truncation got slower by about 10%. There were both gains and losses in the above interval of kernels but we have been able to identify that commit 83929372f629 ("filemap: prepare find and delete operations for huge pages") caused about 10% regression on its own. After some investigation it didn't seem easily possible to fix the regression while maintaining the THP in page cache functionality so we've decided to optimize the page cache truncation path instead to make up for the change. This series is a result of that effort. Patch 1 is an easy speedup of cancel_dirty_page(). Patches 2-6 refactor page cache truncation code so that it is easier to batch radix tree operations. Patch 7 implements batching of deletes from the radix tree which more than makes up for the original regression. This patch (of 7): cancel_dirty_page() does quite some work even for clean pages (fetching of mapping, locking of memcg, atomic bit op on page flags) so it accounts for ~2.5% of cost of truncation of a clean page. That is not much but still dumb for something we don't need at all. Check whether a page is actually dirty and avoid any work if not. Link: http://lkml.kernel.org/r/20171010151937.26984-2-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/page-writeback.c: convert timers to use timer_setup()Kees Cook
In preparation for unconditionally passing the struct timer_list pointer to all timer callbacks, switch to using the new timer_setup() and from_timer() to pass the timer pointer explicitly. Link: http://lkml.kernel.org/r/20171016225913.GA99214@beast Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Jeff Layton <jlayton@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm, soft_offline: improve hugepage soft offlining error logLaszlo Toth
On a failed attempt, we get the following entry: soft offline: 0x3c0000: migration failed 1, type 17ffffc0008008 (uptodate|head) Make this more specific to be straightforward and to follow other error log formats in soft_offline_huge_page(). Link: http://lkml.kernel.org/r/20171016171757.GA3018@ubuntu-desk-vm Signed-off-by: Laszlo Toth <laszlth@gmail.com> Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/page_alloc: make sure __rmqueue() etc are always inlineAaron Lu
__rmqueue(), __rmqueue_fallback(), __rmqueue_smallest() and __rmqueue_cma_fallback() are all in page allocator's hot path and better be finished as soon as possible. One way to make them faster is by making them inline. But as Andrew Morton and Andi Kleen pointed out: https://lkml.org/lkml/2017/10/10/1252 https://lkml.org/lkml/2017/10/10/1279 To make sure they are inlined, we should use __always_inline for them. With the will-it-scale/page_fault1/process benchmark, when using nr_cpu processes to stress buddy, the results for will-it-scale.processes with and without the patch are: On a 2-sockets Intel-Skylake machine: compiler base head gcc-4.4.7 6496131 6911823 +6.4% gcc-4.9.4 7225110 7731072 +7.0% gcc-5.4.1 7054224 7688146 +9.0% gcc-6.2.0 7059794 7651675 +8.4% On a 4-sockets Intel-Skylake machine: compiler base head gcc-4.4.7 13162890 13508193 +2.6% gcc-4.9.4 14997463 15484353 +3.2% gcc-5.4.1 14708711 15449805 +5.0% gcc-6.2.0 14574099 15349204 +5.3% The above 4 compilers are used because I've done the tests through Intel's Linux Kernel Performance(LKP) infrastructure and they are the available compilers there. The benefit being less on 4 sockets machine is due to the lock contention there(perf-profile/native_queued_spin_lock_slowpath=81%) is less severe than on the 2 sockets machine(85%). What the benchmark does is: it forks nr_cpu processes and then each process does the following: 1 mmap() 128M anonymous space; 2 writes to each page there to trigger actual page allocation; 3 munmap() it. in a loop. https://github.com/antonblanchard/will-it-scale/blob/master/tests/page_fault1.c Binary size wise, I have locally built them with different compilers: [aaron@aaronlu obj]$ size */*/mm/page_alloc.o text data bss dec hex filename 37409 9904 8524 55837 da1d gcc-4.9.4/base/mm/page_alloc.o 38273 9904 8524 56701 dd7d gcc-4.9.4/head/mm/page_alloc.o 37465 9840 8428 55733 d9b5 gcc-5.5.0/base/mm/page_alloc.o 38169 9840 8428 56437 dc75 gcc-5.5.0/head/mm/page_alloc.o 37573 9840 8428 55841 da21 gcc-6.4.0/base/mm/page_alloc.o 38261 9840 8428 56529 dcd1 gcc-6.4.0/head/mm/page_alloc.o 36863 9840 8428 55131 d75b gcc-7.2.0/base/mm/page_alloc.o 37711 9840 8428 55979 daab gcc-7.2.0/head/mm/page_alloc.o Text size increased about 800 bytes for mm/page_alloc.o. [aaron@aaronlu obj]$ size */*/vmlinux text data bss dec hex filename 10342757 5903208 17723392 33969357 20654cd gcc-4.9.4/base/vmlinux 10342757 5903208 17723392 33969357 20654cd gcc-4.9.4/head/vmlinux 10332448 5836608 17715200 33884256 2050860 gcc-5.5.0/base/vmlinux 10332448 5836608 17715200 33884256 2050860 gcc-5.5.0/head/vmlinux 10094546 5836696 17715200 33646442 201676a gcc-6.4.0/base/vmlinux 10094546 5836696 17715200 33646442 201676a gcc-6.4.0/head/vmlinux 10018775 5828732 17715200 33562707 2002053 gcc-7.2.0/base/vmlinux 10018775 5828732 17715200 33562707 2002053 gcc-7.2.0/head/vmlinux Text size for vmlinux has no change though, probably due to function alignment. Link: http://lkml.kernel.org/r/20171013063111.GA26032@intel.com Signed-off-by: Aaron Lu <aaron.lu@intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Kemi Wang <kemi.wang@intel.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>
2017-11-15mm: stop zeroing memory during allocation in vmemmapPavel Tatashin
vmemmap_alloc_block() will no longer zero the block, so zero memory at its call sites for everything except struct pages. Struct page memory is zero'd by struct page initialization. Replace allocators in sparse-vmemmap to use the non-zeroing version. So, we will get the performance improvement by zeroing the memory in parallel when struct pages are zeroed. Add struct page zeroing as a part of initialization of other fields in __init_single_page(). This single thread performance collected on: Intel(R) Xeon(R) CPU E7-8895 v3 @ 2.60GHz with 1T of memory (268400646 pages in 8 nodes): BASE FIX sparse_init 11.244671836s 0.007199623s zone_sizes_init 4.879775891s 8.355182299s -------------------------- Total 16.124447727s 8.362381922s sparse_init is where memory for struct pages is zeroed, and the zeroing part is moved later in this patch into __init_single_page(), which is called from zone_sizes_init(). [akpm@linux-foundation.org: make vmemmap_alloc_block_zero() private to sparse-vmemmap.c] Link: http://lkml.kernel.org/r/20171013173214.27300-10-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Tested-by: Bob Picco <bob.picco@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> 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>
2017-11-15mm: zero reserved and unavailable struct pagesPavel Tatashin
Some memory is reserved but unavailable: not present in memblock.memory (because not backed by physical pages), but present in memblock.reserved. Such memory has backing struct pages, but they are not initialized by going through __init_single_page(). In some cases these struct pages are accessed even if they do not contain any data. One example is page_to_pfn() might access page->flags if this is where section information is stored (CONFIG_SPARSEMEM, SECTION_IN_PAGE_FLAGS). One example of such memory: trim_low_memory_range() unconditionally reserves from pfn 0, but e820__memblock_setup() might provide the exiting memory from pfn 1 (i.e. KVM). Since struct pages are zeroed in __init_single_page(), and not during allocation time, we must zero such struct pages explicitly. The patch involves adding a new memblock iterator: for_each_resv_unavail_range(i, p_start, p_end) Which iterates through reserved && !memory lists, and we zero struct pages explicitly by calling mm_zero_struct_page(). === Here is more detailed example of problem that this patch is addressing: Run tested on qemu with the following arguments: -enable-kvm -cpu kvm64 -m 512 -smp 2 This patch reports that there are 98 unavailable pages. They are: pfn 0 and pfns in range [159, 255]. Note, trim_low_memory_range() reserves only pfns in range [0, 15], it does not reserve [159, 255] ones. e820__memblock_setup() reports linux that the following physical ranges are available: [1 , 158] [256, 130783] Notice, that exactly unavailable pfns are missing! Now, lets check what we have in zone 0: [1, 131039] pfn 0, is not part of the zone, but pfns [1, 158], are. However, the bigger problem we have if we do not initialize these struct pages is with memory hotplug. Because, that path operates at 2M boundaries (section_nr). And checks if 2M range of pages is hot removable. It starts with first pfn from zone, rounds it down to 2M boundary (sturct pages are allocated at 2M boundaries when vmemmap is created), and checks if that section is hot removable. In this case start with pfn 1 and convert it down to pfn 0. Later pfn is converted to struct page, and some fields are checked. Now, if we do not zero struct pages, we get unpredictable results. In fact when CONFIG_VM_DEBUG is enabled, and we explicitly set all vmemmap memory to ones, the following panic is observed with kernel test without this patch applied: BUG: unable to handle kernel NULL pointer dereference at (null) IP: is_pageblock_removable_nolock+0x35/0x90 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT ... task: ffff88001f4e2900 task.stack: ffffc90000314000 RIP: 0010:is_pageblock_removable_nolock+0x35/0x90 Call Trace: ? is_mem_section_removable+0x5a/0xd0 show_mem_removable+0x6b/0xa0 dev_attr_show+0x1b/0x50 sysfs_kf_seq_show+0xa1/0x100 kernfs_seq_show+0x22/0x30 seq_read+0x1ac/0x3a0 kernfs_fop_read+0x36/0x190 ? security_file_permission+0x90/0xb0 __vfs_read+0x16/0x30 vfs_read+0x81/0x130 SyS_read+0x44/0xa0 entry_SYSCALL_64_fastpath+0x1f/0xbd Link: http://lkml.kernel.org/r/20171013173214.27300-7-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Tested-by: Bob Picco <bob.picco@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> 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>
2017-11-15mm: define memblock_virt_alloc_try_nid_rawPavel Tatashin
* A new variant of memblock_virt_alloc_* allocations: memblock_virt_alloc_try_nid_raw() - Does not zero the allocated memory - Does not panic if request cannot be satisfied * optimize early system hash allocations Clients can call alloc_large_system_hash() with flag: HASH_ZERO to specify that memory that was allocated for system hash needs to be zeroed, otherwise the memory does not need to be zeroed, and client will initialize it. If memory does not need to be zero'd, call the new memblock_virt_alloc_raw() interface, and thus improve the boot performance. * debug for raw alloctor When CONFIG_DEBUG_VM is enabled, this patch sets all the memory that is returned by memblock_virt_alloc_try_nid_raw() to ones to ensure that no places excpect zeroed memory. Link: http://lkml.kernel.org/r/20171013173214.27300-6-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Tested-by: Bob Picco <bob.picco@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> 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>
2017-11-15mm: deferred_init_memmap improvementsPavel Tatashin
Patch series "complete deferred page initialization", v12. SMP machines can benefit from the DEFERRED_STRUCT_PAGE_INIT config option, which defers initializing struct pages until all cpus have been started so it can be done in parallel. However, this feature is sub-optimal, because the deferred page initialization code expects that the struct pages have already been zeroed, and the zeroing is done early in boot with a single thread only. Also, we access that memory and set flags before struct pages are initialized. All of this is fixed in this patchset. In this work we do the following: - Never read access struct page until it was initialized - Never set any fields in struct pages before they are initialized - Zero struct page at the beginning of struct page initialization ========================================================================== Performance improvements on x86 machine with 8 nodes: Intel(R) Xeon(R) CPU E7-8895 v3 @ 2.60GHz and 1T of memory: TIME SPEED UP base no deferred: 95.796233s fix no deferred: 79.978956s 19.77% base deferred: 77.254713s fix deferred: 55.050509s 40.34% ========================================================================== SPARC M6 3600 MHz with 15T of memory TIME SPEED UP base no deferred: 358.335727s fix no deferred: 302.320936s 18.52% base deferred: 237.534603s fix deferred: 182.103003s 30.44% ========================================================================== Raw dmesg output with timestamps: x86 base no deferred: https://hastebin.com/ofunepurit.scala x86 base deferred: https://hastebin.com/ifazegeyas.scala x86 fix no deferred: https://hastebin.com/pegocohevo.scala x86 fix deferred: https://hastebin.com/ofupevikuk.scala sparc base no deferred: https://hastebin.com/ibobeteken.go sparc base deferred: https://hastebin.com/fariqimiyu.go sparc fix no deferred: https://hastebin.com/muhegoheyi.go sparc fix deferred: https://hastebin.com/xadinobutu.go This patch (of 11): deferred_init_memmap() is called when struct pages are initialized later in boot by slave CPUs. This patch simplifies and optimizes this function, and also fixes a couple issues (described below). The main change is that now we are iterating through free memblock areas instead of all configured memory. Thus, we do not have to check if the struct page has already been initialized. ===== In deferred_init_memmap() where all deferred struct pages are initialized we have a check like this: if (page->flags) { VM_BUG_ON(page_zone(page) != zone); goto free_range; } This way we are checking if the current deferred page has already been initialized. It works, because memory for struct pages has been zeroed, and the only way flags are not zero if it went through __init_single_page() before. But, once we change the current behavior and won't zero the memory in memblock allocator, we cannot trust anything inside "struct page"es until they are initialized. This patch fixes this. The deferred_init_memmap() is re-written to loop through only free memory ranges provided by memblock. Note, this first issue is relevant only when the following change is merged: ===== This patch fixes another existing issue on systems that have holes in zones i.e CONFIG_HOLES_IN_ZONE is defined. In for_each_mem_pfn_range() we have code like this: if (!pfn_valid_within(pfn) goto free_range; Note: 'page' is not set to NULL and is not incremented but 'pfn' advances. Thus means if deferred struct pages are enabled on systems with these kind of holes, linux would get memory corruptions. I have fixed this issue by defining a new macro that performs all the necessary operations when we free the current set of pages. [pasha.tatashin@oracle.com: buddy page accessed before initialized] Link: http://lkml.kernel.org/r/20171102170221.7401-2-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20171013173214.27300-2-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Tested-by: Bob Picco <bob.picco@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/swap_state.c: declare a few variables as __read_mostlyChangbin Du
These global variables are only set during initialization or rarely change, so declare them as __read_mostly. Link: http://lkml.kernel.org/r/1507802349-5554-1-git-send-email-changbin.du@intel.com Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15kmemcheck: rip it outLevin, Alexander (Sasha Levin)
Fix up makefiles, remove references, and git rm kmemcheck. Link: http://lkml.kernel.org/r/20171007030159.22241-4-alexander.levin@verizon.com Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Vegard Nossum <vegardno@ifi.uio.no> Cc: Pekka Enberg <penberg@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Alexander Potapenko <glider@google.com> Cc: Tim Hansen <devtimhansen@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15kmemcheck: remove whats left of NOTRACK flagsLevin, Alexander (Sasha Levin)
Now that kmemcheck is gone, we don't need the NOTRACK flags. Link: http://lkml.kernel.org/r/20171007030159.22241-5-alexander.levin@verizon.com Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Alexander Potapenko <glider@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Hansen <devtimhansen@gmail.com> Cc: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACKLevin, Alexander (Sasha Levin)
Convert all allocations that used a NOTRACK flag to stop using it. Link: http://lkml.kernel.org/r/20171007030159.22241-3-alexander.levin@verizon.com Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Alexander Potapenko <glider@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Hansen <devtimhansen@gmail.com> Cc: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15kmemcheck: remove annotationsLevin, Alexander (Sasha Levin)
Patch series "kmemcheck: kill kmemcheck", v2. As discussed at LSF/MM, kill kmemcheck. KASan is a replacement that is able to work without the limitation of kmemcheck (single CPU, slow). KASan is already upstream. We are also not aware of any users of kmemcheck (or users who don't consider KASan as a suitable replacement). The only objection was that since KASAN wasn't supported by all GCC versions provided by distros at that time we should hold off for 2 years, and try again. Now that 2 years have passed, and all distros provide gcc that supports KASAN, kill kmemcheck again for the very same reasons. This patch (of 4): Remove kmemcheck annotations, and calls to kmemcheck from the kernel. [alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs] Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Alexander Potapenko <glider@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Hansen <devtimhansen@gmail.com> Cc: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15mm/rmap.c: remove redundant variable cendColin Ian King
Variable cend is set but never read, hence it is redundant and can be removed. Cleans up clang build warning: Value stored to 'cend' is never read Link: http://lkml.kernel.org/r/20171011174942.1372-1-colin.king@canonical.com Fixes: 369ea8242c0f ("mm/rmap: update to new mmu_notifier semantic v2") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>