summaryrefslogtreecommitdiff
path: root/mm
AgeCommit message (Collapse)Author
2015-04-15mm/compaction: reset compaction scanner positionsGioh Kim
When the compaction is activated via /proc/sys/vm/compact_memory it would better scan the whole zone. And some platforms, for instance ARM, have the start_pfn of a zone at zero. Therefore the first try to compact via /proc doesn't work. It needs to reset the compaction scanner position first. Signed-off-by: Gioh Kim <gioh.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15mm, memcg: sync allocation and memcg charge gfp flags for THPMichal Hocko
memcg currently uses hardcoded GFP_TRANSHUGE gfp flags for all THP charges. THP allocations, however, might be using different flags depending on /sys/kernel/mm/transparent_hugepage/{,khugepaged/}defrag and the current allocation context. The primary difference is that defrag configured to "madvise" value will clear __GFP_WAIT flag from the core gfp mask to make the allocation lighter for all mappings which are not backed by VM_HUGEPAGE vmas. If memcg charge path ignores this fact we will get light allocation but the a potential memcg reclaim would kill the whole point of the configuration. Fix the mismatch by providing the same gfp mask used for the allocation to the charge functions. This is quite easy for all paths except for hugepaged kernel thread with !CONFIG_NUMA which is doing a pre-allocation long before the allocated page is used in collapse_huge_page via khugepaged_alloc_page. To prevent from cluttering the whole code path from khugepaged_do_scan we simply return the current flags as per khugepaged_defrag() value which might have changed since the preallocation. If somebody changed the value of the knob we would charge differently but this shouldn't happen often and it is definitely not critical because it would only lead to a reduced success rate of one-off THP promotion. [akpm@linux-foundation.org: fix weird code layout while we're there] [rientjes@google.com: clean up around alloc_hugepage_gfpmask()] Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15mm: rename deactivate_page to deactivate_file_pageMinchan Kim
"deactivate_page" was created for file invalidation so it has too specific logic for file-backed pages. So, let's change the name of the function and date to a file-specific one and yield the generic name. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shli@kernel.org> Cc: Wang, Yalin <Yalin.Wang@sonymobile.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15mm: allow compaction of unevictable pagesEric B Munson
Currently, pages which are marked as unevictable are protected from compaction, but not from other types of migration. The POSIX real time extension explicitly states that mlock() will prevent a major page fault, but the spirit of this is that mlock() should give a process the ability to control sources of latency, including minor page faults. However, the mlock manpage only explicitly says that a locked page will not be written to swap and this can cause some confusion. The compaction code today does not give a developer who wants to avoid swap but wants to have large contiguous areas available any method to achieve this state. This patch introduces a sysctl for controlling compaction behavior with respect to the unevictable lru. Users who demand no page faults after a page is present can set compact_unevictable_allowed to 0 and users who need the large contiguous areas can enable compaction on locked memory by leaving the default value of 1. To illustrate this problem I wrote a quick test program that mmaps a large number of 1MB files filled with random data. These maps are created locked and read only. Then every other mmap is unmapped and I attempt to allocate huge pages to the static huge page pool. When the compact_unevictable_allowed sysctl is 0, I cannot allocate hugepages after fragmenting memory. When the value is set to 1, allocations succeed. Signed-off-by: Eric B Munson <emunson@akamai.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Christoph Lameter <cl@linux.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15mm/page-writeback: check-before-clear PageReclaimNaoya Horiguchi
With the page flag sanitization patchset, an invalid usage of ClearPageReclaim() is detected in set_page_dirty(). This can be called from __unmap_hugepage_range(), so let's check PageReclaim() before trying to clear it to avoid the misuse. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.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>
2015-04-15mm/migrate: check-before-clear PageSwapCacheNaoya Horiguchi
With the page flag sanitization patchset, an invalid usage of ClearPageSwapCache() is detected in migration_page_copy(). migrate_page_copy() is shared by both normal and hugepage (both thp and hugetlb) code path, so let's check PageSwapCache() and clear it if it's set to avoid misuse of the invalid clear operation. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.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>
2015-04-15mm/memory-failure.c: define page types for action_result() in one placeNaoya Horiguchi
This cleanup patch moves all strings passed to action_result() into a singl= e array action_page_type so that a reader can easily find which kind of actio= n results are possible. And this patch also fixes the odd lines to be printed out, like "unknown page state page" or "free buddy, 2nd try page". [akpm@linux-foundation.org: rename messages, per David] [akpm@linux-foundation.org: s/DIRTY_UNEVICTABLE_LRU/CLEAN_UNEVICTABLE_LRU', per Andi] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: "Xie XiuQi" <xiexiuqi@huawei.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Chen Gong <gong.chen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15memcg: remove obsolete commentVladimir Davydov
Low and high watermarks, as they defined in the TODO to the mem_cgroup struct, have already been implemented by Johannes, so remove the stale comment. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15memcg: zap mem_cgroup_lookup()Vladimir Davydov
mem_cgroup_lookup() is a wrapper around mem_cgroup_from_id(), which checks that id != 0 before issuing the function call. Today, there is no point in this additional check apart from optimization, because there is no css with id <= 0, so that css_from_id, called by mem_cgroup_from_id, will return NULL for any id <= 0. Since mem_cgroup_from_id is only called from mem_cgroup_lookup, let us zap mem_cgroup_lookup, substituting calls to it with mem_cgroup_from_id and moving the check if id > 0 to css_from_id. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Acked-by: Michal Hocko <mhocko@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>
2015-04-15mm/oom_kill.c: fix typo in commentYaowei Bai
Alter 'taks' -> 'task' Signed-off-by: Yaowei Bai <bywxiaobai@163.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15Merge branch 'for-linus-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second vfs update from Al Viro: "Now that net-next went in... Here's the next big chunk - killing ->aio_read() and ->aio_write(). There'll be one more pile today (direct_IO changes and generic_write_checks() cleanups/fixes), but I'd prefer to keep that one separate" * 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits) ->aio_read and ->aio_write removed pcm: another weird API abuse infinibad: weird APIs switched to ->write_iter() kill do_sync_read/do_sync_write fuse: use iov_iter_get_pages() for non-splice path fuse: switch to ->read_iter/->write_iter switch drivers/char/mem.c to ->read_iter/->write_iter make new_sync_{read,write}() static coredump: accept any write method switch /dev/loop to vfs_iter_write() serial2002: switch to __vfs_read/__vfs_write ashmem: use __vfs_read() export __vfs_read() autofs: switch to __vfs_write() new helper: __vfs_write() switch hugetlbfs to ->read_iter() coda: switch to ->read_iter/->write_iter ncpfs: switch to ->read_iter/->write_iter net/9p: remove (now-)unused helpers p9_client_attach(): set fid->uid correctly ...
2015-04-15VFS: assorted weird filesystems: d_inode() annotationsDavid Howells
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-14Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge first patchbomb from Andrew Morton: - arch/sh updates - ocfs2 updates - kernel/watchdog feature - about half of mm/ * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits) Documentation: update arch list in the 'memtest' entry Kconfig: memtest: update number of test patterns up to 17 arm: add support for memtest arm64: add support for memtest memtest: use phys_addr_t for physical addresses mm: move memtest under mm mm, hugetlb: abort __get_user_pages if current has been oom killed mm, mempool: do not allow atomic resizing memcg: print cgroup information when system panics due to panic_on_oom mm: numa: remove migrate_ratelimited mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE mm: split ET_DYN ASLR from mmap ASLR s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE mm: expose arch_mmap_rnd when available s390: standardize mmap_rnd() usage powerpc: standardize mmap_rnd() usage mips: extract logic for mmap_rnd() arm64: standardize mmap_rnd() usage x86: standardize mmap_rnd() usage arm: factor out mmap ASLR into mmap_rnd ...
2015-04-14memtest: use phys_addr_t for physical addressesVladimir Murzin
Since memtest might be used by other architectures pass input parameters as phys_addr_t instead of long to prevent overflow. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: move memtest under mmVladimir Murzin
Memtest is a simple feature which fills the memory with a given set of patterns and validates memory contents, if bad memory regions is detected it reserves them via memblock API. Since memblock API is widely used by other architectures this feature can be enabled outside of x86 world. This patch set promotes memtest to live under generic mm umbrella and enables memtest feature for arm/arm64. It was reported that this patch set was useful for tracking down an issue with some errant DMA on an arm64 platform. This patch (of 6): There is nothing platform dependent in the core memtest code, so other platforms might benefit from this feature too. [linux@roeck-us.net: MEMTEST depends on MEMBLOCK] Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm, hugetlb: abort __get_user_pages if current has been oom killedDavid Rientjes
If __get_user_pages() is faulting a significant number of hugetlb pages, usually as the result of mmap(MAP_LOCKED), it can potentially allocate a very large amount of memory. If the process has been oom killed, this will cause a lot of memory to potentially deplete memory reserves. In the same way that commit 4779280d1ea4 ("mm: make get_user_pages() interruptible") aborted for pending SIGKILLs when faulting non-hugetlb memory, based on the premise of commit 462e00cc7151 ("oom: stop allocating user memory if TIF_MEMDIE is set"), hugetlb page faults now terminate when the process has been oom killed. Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Greg Thelen <gthelen@google.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Acked-by: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm, mempool: do not allow atomic resizingDavid Rientjes
Allocating a large number of elements in atomic context could quickly deplete memory reserves, so just disallow atomic resizing entirely. Nothing currently uses mempool_resize() with anything other than GFP_KERNEL, so convert existing callers to drop the gfp_mask. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Steffen Maier <maier@linux.vnet.ibm.com> [zfcp] Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Steve French <sfrench@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14memcg: print cgroup information when system panics due to panic_on_oomBalasubramani Vivekanandan
If kernel panics due to oom, caused by a cgroup reaching its limit, when 'compulsory panic_on_oom' is enabled, then we will only see that the OOM happened because of "compulsory panic_on_oom is enabled" but this doesn't tell the difference between mempolicy and memcg. And dumping system wide information is plain wrong and more confusing. This patch provides the information of the cgroup whose limit triggerred panic Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com> Acked-by: Michal Hocko <mhocko@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>
2015-04-14mm: numa: remove migrate_ratelimitedMel Gorman
This code is dead since commit 9e645ab6d089 ("sched/numa: Continue PTE scanning even if migrate rate limited") so remove it. Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: memcontrol: let mem_cgroup_move_account() have effect only if MMU enabledChen Gang
When !MMU, it will report warning. The related warning with allmodconfig under c6x: CC mm/memcontrol.o mm/memcontrol.c:2802:12: warning: 'mem_cgroup_move_account' defined but not used [-Wunused-function] static int mem_cgroup_move_account(struct page *page, ^ Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: change vunmap to tear down huge KVA mappingsToshi Kani
Change vunmap_pmd_range() and vunmap_pud_range() to tear down huge KVA mappings when they are set. pud_clear_huge() and pmd_clear_huge() return zero when no-operation is performed, i.e. huge page mapping was not used. These changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined on the architecture. [akpm@linux-foundation.org: use consistent code layout] Signed-off-by: Toshi Kani <toshi.kani@hp.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Robert Elliott <Elliott@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: change __get_vm_area_node() to use fls_long()Toshi Kani
ioremap() and its related interfaces are used to create I/O mappings to memory-mapped I/O devices. The mapping sizes of the traditional I/O devices are relatively small. Non-volatile memory (NVM), however, has many GB and is going to have TB soon. It is not very efficient to create large I/O mappings with 4KB. This patchset extends the ioremap() interfaces to transparently create I/O mappings with huge pages whenever possible. ioremap() continues to use 4KB mappings when a huge page does not fit into a requested range. There is no change necessary to the drivers using ioremap(). A requested physical address must be aligned by a huge page size (1GB or 2MB on x86) for using huge page mapping, though. The kernel huge I/O mapping will improve performance of NVM and other devices with large memory, and reduce the time to create their mappings as well. On x86, MTRRs can override PAT memory types with a 4KB granularity. When using a huge page, MTRRs can override the memory type of the huge page, which may lead a performance penalty. The processor can also behave in an undefined manner if a huge page is mapped to a memory range that MTRRs have mapped with multiple different memory types. Therefore, the mapping code falls back to use a smaller page size toward 4KB when a mapping range is covered by non-WB type of MTRRs. The WB type of MTRRs has no affect on the PAT memory types. The patchset introduces HAVE_ARCH_HUGE_VMAP, which indicates that the arch supports huge KVA mappings for ioremap(). User may specify a new kernel option "nohugeiomap" to disable the huge I/O mapping capability of ioremap() when necessary. Patch 1-4 change common files to support huge I/O mappings. There is no change in the functinalities unless HAVE_ARCH_HUGE_VMAP is defined on the architecture of the system. Patch 5-6 implement the HAVE_ARCH_HUGE_VMAP funcs on x86, and set HAVE_ARCH_HUGE_VMAP on x86. This patch (of 6): __get_vm_area_node() takes unsigned long size, which is a 64-bit value on a 64-bit kernel. However, fls(size) simply ignores the upper 32-bit. Change to use fls_long() to handle the size properly. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Robert Elliott <Elliott@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm/page_alloc.c: clean up commentYaowei Bai
Signed-off-by: Yaowei Bai <bywxiaobai@163.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: cma: constify and use correct signness in mm/cma.cSasha Levin
Constify function parameters and use correct signness where needed. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Acked-by: Gregory Fong <gregory.0xf0@gmail.com> Cc: Pintu Kumar <pintu.k@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm, thp: really limit transparent hugepage allocation to local nodeDavid Rientjes
Commit 077fcf116c8c ("mm/thp: allocate transparent hugepages on local node") restructured alloc_hugepage_vma() with the intent of only allocating transparent hugepages locally when there was not an effective interleave mempolicy. alloc_pages_exact_node() does not limit the allocation to the single node, however, but rather prefers it. This is because __GFP_THISNODE is not set which would cause the node-local nodemask to be passed. Without it, only a nodemask that prefers the local node is passed. Fix this by passing __GFP_THISNODE and falling back to small pages when the allocation fails. Commit 9f1b868a13ac ("mm: thp: khugepaged: add policy for finding target node") suffers from a similar problem for khugepaged, which is also fixed. Fixes: 077fcf116c8c ("mm/thp: allocate transparent hugepages on local node") Fixes: 9f1b868a13ac ("mm: thp: khugepaged: add policy for finding target node") Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Pravin Shelar <pshelar@nicira.com> Cc: Jarno Rajahalme <jrajahalme@nicira.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Greg Thelen <gthelen@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: remove GFP_THISNODEDavid Rientjes
NOTE: this is not about __GFP_THISNODE, this is only about GFP_THISNODE. GFP_THISNODE is a secret combination of gfp bits that have different behavior than expected. It is a combination of __GFP_THISNODE, __GFP_NORETRY, and __GFP_NOWARN and is special-cased in the page allocator slowpath to fail without trying reclaim even though it may be used in combination with __GFP_WAIT. An example of the problem this creates: commit e97ca8e5b864 ("mm: fix GFP_THISNODE callers and clarify") fixed up many users of GFP_THISNODE that really just wanted __GFP_THISNODE. The problem doesn't end there, however, because even it was a no-op for alloc_misplaced_dst_page(), which also sets __GFP_NORETRY and __GFP_NOWARN, and migrate_misplaced_transhuge_page(), where __GFP_NORETRY and __GFP_NOWAIT is set in GFP_TRANSHUGE. Converting GFP_THISNODE to __GFP_THISNODE is a no-op in these cases since the page allocator special-cases __GFP_THISNODE && __GFP_NORETRY && __GFP_NOWARN. It's time to just remove GFP_THISNODE entirely. We leave __GFP_THISNODE to restrict an allocation to a local node, but remove GFP_THISNODE and its obscurity. Instead, we require that a caller clear __GFP_WAIT if it wants to avoid reclaim. This allows the aforementioned functions to actually reclaim as they should. It also enables any future callers that want to do __GFP_THISNODE but also __GFP_NORETRY && __GFP_NOWARN to reclaim. The rule is simple: if you don't want to reclaim, then don't set __GFP_WAIT. Aside: ovs_flow_stats_update() really wants to avoid reclaim as well, so it is unchanged. Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Pravin Shelar <pshelar@nicira.com> Cc: Jarno Rajahalme <jrajahalme@nicira.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Greg Thelen <gthelen@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm, mempolicy: migrate_to_node should only migrate to nodeDavid Rientjes
migrate_to_node() is intended to migrate a page from one source node to a target node. Today, migrate_to_node() could end up migrating to any node, not only the target node. This is because the page migration allocator, new_node_page() does not pass __GFP_THISNODE to alloc_pages_exact_node(). This causes the target node to be preferred but allows fallback to any other node in order of affinity. Prevent this by allocating with __GFP_THISNODE. If memory is not available, -ENOMEM will be returned as appropriate. Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14cleancache: remove limit on the number of cleancache enabled filesystemsVladimir Davydov
The limit equals 32 and is imposed by the number of entries in the fs_poolid_map and shared_fs_poolid_map. Nowadays it is insufficient, because with containers on board a Linux host can have hundreds of active fs mounts. These maps were introduced by commit 49a9ab815acb8 ("mm: cleancache: lazy initialization to allow tmem backends to build/run as modules") in order to allow compiling cleancache drivers as modules. Real pool ids are stored in these maps while super_block->cleancache_poolid points to an entry in the map, so that on cleancache registration we can walk over all (if there are <= 32 of them, of course) cleancache-enabled super blocks and assign real pool ids. Actually, there is absolutely no need in these maps, because we can iterate over all super blocks immediately using iterate_supers. This is not racy, because cleancache_init_ops is called from mount_fs with super_block->s_umount held for writing, while iterate_supers takes this semaphore for reading, so if we call iterate_supers after setting cleancache_ops, all super blocks that had been created before cleancache_register_ops was called will be assigned pool ids by the action function of iterate_supers while all newer super blocks will receive it in cleancache_init_fs. This patch therefore removes the maps and hence the artificial limit on the number of cleancache enabled filesystems. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Stefan Hengelein <ilendir@googlemail.com> Cc: Florian Schmaus <fschmaus@gmail.com> Cc: Andor Daam <andor.daam@googlemail.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Bob Liu <lliubbo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14cleancache: forbid overriding cleancache_opsVladimir Davydov
Currently, cleancache_register_ops returns the previous value of cleancache_ops to allow chaining. However, chaining, as it is implemented now, is extremely dangerous due to possible pool id collisions. Suppose, a new cleancache driver is registered after the previous one assigned an id to a super block. If the new driver assigns the same id to another super block, which is perfectly possible, we will have two different filesystems using the same id. No matter if the new driver implements chaining or not, we are likely to get data corruption with such a configuration eventually. This patch therefore disables the ability to override cleancache_ops altogether as potentially dangerous. If there is already cleancache driver registered, all further calls to cleancache_register_ops will return EBUSY. Since no user of cleancache implements chaining, we only need to make minor changes to the code outside the cleancache core. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Stefan Hengelein <ilendir@googlemail.com> Cc: Florian Schmaus <fschmaus@gmail.com> Cc: Andor Daam <andor.daam@googlemail.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Bob Liu <lliubbo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14cleancache: zap uuid arg of cleancache_init_shared_fsVladimir Davydov
Use super_block->s_uuid instead. Every shared filesystem using cleancache must now initialize super_block->s_uuid before calling cleancache_init_shared_fs. The only one on the tree, ocfs2, already meets this requirement. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Stefan Hengelein <ilendir@googlemail.com> Cc: Florian Schmaus <fschmaus@gmail.com> Cc: Andor Daam <andor.daam@googlemail.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Bob Liu <lliubbo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: refactor do_wp_page handling of shared vma into a functionShachar Raindel
The do_wp_page function is extremely long. Extract the logic for handling a page belonging to a shared vma into a function of its own. This helps the readability of the code, without doing any functional change in it. Signed-off-by: Shachar Raindel <raindel@mellanox.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Haggai Eran <haggaie@mellanox.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Feiner <pfeiner@google.com> Cc: Michel Lespinasse <walken@google.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: refactor do_wp_page, extract the page copy flowShachar Raindel
In some cases, do_wp_page had to copy the page suffering a write fault to a new location. If the function logic decided that to do this, it was done by jumping with a "goto" operation to the relevant code block. This made the code really hard to understand. It is also against the kernel coding style guidelines. This patch extracts the page copy and page table update logic to a separate function. It also clean up the naming, from "gotten" to "wp_page_copy", and adds few comments. Signed-off-by: Shachar Raindel <raindel@mellanox.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Haggai Eran <haggaie@mellanox.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Feiner <pfeiner@google.com> Cc: Michel Lespinasse <walken@google.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: refactor do_wp_page - rewrite the unlock flowShachar Raindel
When do_wp_page is ending, in several cases it needs to unlock the pages and ptls it was accessing. Currently, this logic was "called" by using a goto jump. This makes following the control flow of the function harder. Readability was further hampered by the unlock case containing large amount of logic needed only in one of the 3 cases. Using goto for cleanup is generally allowed. However, moving the trivial unlocking flows to the relevant call sites allow deeper refactoring in the next patch. Signed-off-by: Shachar Raindel <raindel@mellanox.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Haggai Eran <haggaie@mellanox.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Feiner <pfeiner@google.com> Cc: Michel Lespinasse <walken@google.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: refactor do_wp_page, extract the reuse caseShachar Raindel
Currently do_wp_page contains 265 code lines. It also contains 9 goto statements, of which 5 are targeting labels which are not cleanup related. This makes the function extremely difficult to understand. The following patches are an attempt at breaking the function to its basic components, and making it easier to understand. The patches are straight forward function extractions from do_wp_page. As we extract functions, we remove unneeded parameters and simplify the code as much as possible. However, the functionality is supposed to remain completely unchanged. The patches also attempt to document the functionality of each extracted function. In patch 2, we split the unlock logic to the contain logic relevant to specific needs of each use case, instead of having huge number of conditional decisions in a single unlock flow. This patch (of 4): When do_wp_page is ending, in several cases it needs to reuse the existing page. This is achieved by making the page table writable, and possibly updating the page-cache state. Currently, this logic was "called" by using a goto jump. This makes following the control flow of the function harder. It is also against the coding style guidelines for using goto. As the code can easily be refactored into a specialized function, refactor it out and simplify the code flow in do_wp_page. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Haggai Eran <haggaie@mellanox.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Feiner <pfeiner@google.com> Cc: Michel Lespinasse <walken@google.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: completely remove dumping per-cpu lists from show_mem()Konstantin Khlebnikov
It seems nobody needs this. Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: hide per-cpu lists in output of show_mem()Konstantin Khlebnikov
This makes show_mem() much less verbose on huge machines. Instead of huge and almost useless dump of counters for each per-zone per-cpu lists this patch prints the sum of these counters for each zone (free_pcp) and size of per-cpu list for current cpu (local_pcp). The filter flag SHOW_MEM_PERCPU_LISTS reverts to the old verbose mode. [akpm@linux-foundation.org: update show_free_areas comment] Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14page_writeback: clean up mess around cancel_dirty_page()Konstantin Khlebnikov
This patch replaces cancel_dirty_page() with a helper function account_page_cleaned() which only updates counters. It's called from truncate_complete_page() and from try_to_free_buffers() (hack for ext3). Page is locked in both cases, page-lock protects against concurrent dirtiers: see commit 2d6d7f982846 ("mm: protect set_page_dirty() from ongoing truncation"). Delete_from_page_cache() shouldn't be called for dirty pages, they must be handled by caller (either written or truncated). This patch treats final dirty accounting fixup at the end of __delete_from_page_cache() as a debug check and adds WARN_ON_ONCE() around it. If something removes dirty pages without proper handling that might be a bug and unwritten data might be lost. Hugetlbfs has no dirty pages accounting, ClearPageDirty() is enough here. cancel_dirty_page() in nfs_wb_page_cancel() is redundant. This is helper for nfs_invalidate_page() and it's called only in case complete invalidation. The mess was started in v2.6.20 after commits 46d2277c796f ("Clean up and make try_to_free_buffers() not race with dirty pages") and 3e67c0987d75 ("truncate: clear page dirtiness before running try_to_free_buffers()") first was reverted right in v2.6.20 in commit ecdfc9787fe5 ("Resurrect 'try_to_free_buffers()' VM hackery"), second in v2.6.25 commit a2b345642f53 ("Fix dirty page accounting leak with ext3 data=journal"). Custom fixes were introduced between these points. NFS in v2.6.23, commit 1b3b4a1a2deb ("NFS: Fix a write request leak in nfs_invalidate_page()"). Kludge in __delete_from_page_cache() in v2.6.24, commit 3a6927906f1b ("Do dirty page accounting when removing a page from the page cache"). Since v2.6.25 all of them are redundant. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Tejun Heo <tj@kernel.org> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: incorporate zero pages into transparent huge pagesEbru Akagunduz
This patch improves THP collapse rates, by allowing zero pages. Currently THP can collapse 4kB pages into a THP when there are up to khugepaged_max_ptes_none pte_none ptes in a 2MB range. This patch counts pte none and mapped zero pages with the same variable. The patch was tested with a program that allocates 800MB of memory, and performs interleaved reads and writes, in a pattern that causes some 2MB areas to first see read accesses, resulting in the zero pfn being mapped there. To simulate memory fragmentation at allocation time, I modified do_huge_pmd_anonymous_page to return VM_FAULT_FALLBACK for read faults. Without the patch, only %50 of the program was collapsed into THP and the percentage did not increase over time. With this patch after 10 minutes of waiting khugepaged had collapsed %99 of the program's memory. [aarcange@redhat.com: fix bogus BUG()] Signed-off-by: Ebru Akagunduz <ebru.akagunduz@gmail.com> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm/compaction: enhance compaction finish conditionJoonsoo Kim
Compaction has anti fragmentation algorithm. It is that freepage should be more than pageblock order to finish the compaction if we don't find any freepage in requested migratetype buddy list. This is for mitigating fragmentation, but, there is a lack of migratetype consideration and it is too excessive compared to page allocator's anti fragmentation algorithm. Not considering migratetype would cause premature finish of compaction. For example, if allocation request is for unmovable migratetype, freepage with CMA migratetype doesn't help that allocation and compaction should not be stopped. But, current logic regards this situation as compaction is no longer needed, so finish the compaction. Secondly, condition is too excessive compared to page allocator's logic. We can steal freepage from other migratetype and change pageblock migratetype on more relaxed conditions in page allocator. This is designed to prevent fragmentation and we can use it here. Imposing hard constraint only to the compaction doesn't help much in this case since page allocator would cause fragmentation again. To solve these problems, this patch borrows anti fragmentation logic from page allocator. It will reduce premature compaction finish in some cases and reduce excessive compaction work. stress-highalloc test in mmtests with non movable order 7 allocation shows considerable increase of compaction success rate. Compaction success rate (Compaction success * 100 / Compaction stalls, %) 31.82 : 42.20 I tested it on non-reboot 5 runs stress-highalloc benchmark and found that there is no more degradation on allocation success rate than before. That roughly means that this patch doesn't result in more fragmentations. Vlastimil suggests additional idea that we only test for fallbacks when migration scanner has scanned a whole pageblock. It looked good for fragmentation because chance of stealing increase due to making more free pages in certain pageblock. So, I tested it, but, it results in decreased compaction success rate, roughly 38.00. I guess the reason that if system is low memory condition, watermark check could be failed due to not enough order 0 free page and so, sometimes, we can't reach a fallback check although migrate_pfn is aligned to pageblock_nr_pages. I can insert code to cope with this situation but it makes code more complicated so I don't include his idea at this patch. [akpm@linux-foundation.org: fix CONFIG_CMA=n build] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm/page_alloc: factor out fallback freepage checkingJoonsoo Kim
This is preparation step to use page allocator's anti fragmentation logic in compaction. This patch just separates fallback freepage checking part from fallback freepage management part. Therefore, there is no functional change. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm/cma: change fallback behaviour for CMA freepageJoonsoo Kim
Freepage with MIGRATE_CMA can be used only for MIGRATE_MOVABLE and they should not be expanded to other migratetype buddy list to protect them from unmovable/reclaimable allocation. Implementing these requirements in __rmqueue_fallback(), that is, finding largest possible block of freepage has bad effect that high order freepage with MIGRATE_CMA are broken continually although there are suitable order CMA freepage. Reason is that they are not be expanded to other migratetype buddy list and next __rmqueue_fallback() invocation try to finds another largest block of freepage and break it again. So, MIGRATE_CMA fallback should be handled separately. This patch introduces __rmqueue_cma_fallback(), that just wrapper of __rmqueue_smallest() and call it before __rmqueue_fallback() if migratetype == MIGRATE_MOVABLE. This results in unintended behaviour change that MIGRATE_CMA freepage is always used first rather than other migratetype as movable allocation's fallback. But, as already mentioned above, MIGRATE_CMA can be used only for MIGRATE_MOVABLE, so it is better to use MIGRATE_CMA freepage first as much as possible. Otherwise, we needlessly take up precious freepages with other migratetype and increase chance of fragmentation. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm, hotplug: fix concurrent memory hot-add deadlockDavid Rientjes
There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm-cma-allocation-trigger-fixAndrew Morton
s/CONFIG_CMA_ALIGNMENT/0/, per Joonsoo Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: cma: release triggerSasha Levin
Provides a userspace interface to trigger a CMA release. Usage: echo [pages] > free This would provide testing/fuzzing access to the CMA release paths. [akpm@linux-foundation.org: coding-style fixes] [mhocko@suse.cz: fix build] Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: cma: allocation triggerSasha Levin
Provides a userspace interface to trigger a CMA allocation. Usage: echo [pages] > alloc This would provide testing/fuzzing access to the CMA allocation paths. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: cma: debugfs interfaceSasha Levin
I've noticed that there is no interfaces exposed by CMA which would let me fuzz what's going on in there. This small patchset exposes some information out to userspace, plus adds the ability to trigger allocation and freeing from userspace. This patch (of 3): Implement a simple debugfs interface to expose information about CMA areas in the system. Useful for testing/sanity checks for CMA since it was impossible to previously retrieve this information in userspace. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14memory hotplug: use macro to switch between section and pfnSheng Yong
Use macro section_nr_to_pfn() to switch between section and pfn, instead of open-coding it. No semantic changes. Signed-off-by: Sheng Yong <shengyong1@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: memcontrol: update copyright noticeJohannes Weiner
Add myself to the list of copyright holders. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm/memblock.c: rename local variable of memblock_type to `type'Baoquan He
A small cleanup. Seems in e3239ff9 ("memblock: Rename memblock_region to memblock_type and memblock_property to memblock_region") this one was missed. Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: move mm_populate()-related code to mm/gup.cKirill A. Shutemov
It's odd that we have populate_vma_page_range() and __mm_populate() in mm/mlock.c. It's implementation of generic memory population and mlocking is one of possible side effect, if VM_LOCKED is set. __get_user_pages() is core of the implementation. Let's move the code into mm/gup.c. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>