- 08 10月, 2016 40 次提交
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由 Reza Arbab 提交于
If store_mem_state() is called to online memory which is already online, it will return 1, the value it got from device_online(). This is wrong because store_mem_state() is a device_attribute .store function. Thus a non-negative return value represents input bytes read. Set the return value to -EINVAL in this case. Link: http://lkml.kernel.org/r/1472743777-24266-1-git-send-email-arbab@linux.vnet.ibm.comSigned-off-by: NReza Arbab <arbab@linux.vnet.ibm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Chen Yucong <slaoub@gmail.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Seth Jennings <sjenning@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 James Morse 提交于
mem_cgroup_count_precharge() and mem_cgroup_move_charge() both call walk_page_range() on the range 0 to ~0UL, neither provide a pte_hole callback, which causes the current implementation to skip non-vma regions. This is all fine but follow up changes would like to make walk_page_range more generic so it is better to be explicit about which range to traverse so let's use highest_vm_end to explicitly traverse only user mmaped memory. [mhocko@kernel.org: rewrote changelog] Link: http://lkml.kernel.org/r/1472655897-22532-1-git-send-email-james.morse@arm.comSigned-off-by: NJames Morse <james.morse@arm.com> Acked-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Aaron Lu 提交于
The global zero page is used to satisfy an anonymous read fault. If THP(Transparent HugePage) is enabled then the global huge zero page is used. The global huge zero page uses an atomic counter for reference counting and is allocated/freed dynamically according to its counter value. CPU time spent on that counter will greatly increase if there are a lot of processes doing anonymous read faults. This patch proposes a way to reduce the access to the global counter so that the CPU load can be reduced accordingly. To do this, a new flag of the mm_struct is introduced: MMF_USED_HUGE_ZERO_PAGE. With this flag, the process only need to touch the global counter in two cases: 1 The first time it uses the global huge zero page; 2 The time when mm_user of its mm_struct reaches zero. Note that right now, the huge zero page is eligible to be freed as soon as its last use goes away. With this patch, the page will not be eligible to be freed until the exit of the last process from which it was ever used. And with the use of mm_user, the kthread is not eligible to use huge zero page either. Since no kthread is using huge zero page today, there is no difference after applying this patch. But if that is not desired, I can change it to when mm_count reaches zero. Case used for test on Haswell EP: usemem -n 72 --readonly -j 0x200000 100G Which spawns 72 processes and each will mmap 100G anonymous space and then do read only access to that space sequentially with a step of 2MB. CPU cycles from perf report for base commit: 54.03% usemem [kernel.kallsyms] [k] get_huge_zero_page CPU cycles from perf report for this commit: 0.11% usemem [kernel.kallsyms] [k] mm_get_huge_zero_page Performance(throughput) of the workload for base commit: 1784430792 Performance(throughput) of the workload for this commit: 4726928591 164% increase. Runtime of the workload for base commit: 707592 us Runtime of the workload for this commit: 303970 us 50% drop. Link: http://lkml.kernel.org/r/fe51a88f-446a-4622-1363-ad1282d71385@intel.comSigned-off-by: NAaron Lu <aaron.lu@intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Ebru Akagunduz <ebru.akagunduz@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 James Morse 提交于
Trying to walk all of virtual memory requires architecture specific knowledge. On x86_64, addresses must be sign extended from bit 48, whereas on arm64 the top VA_BITS of address space have their own set of page tables. clear_refs_write() calls walk_page_range() on the range 0 to ~0UL, it provides a test_walk() callback that only expects to be walking over VMAs. Currently walk_pmd_range() will skip memory regions that don't have a VMA, reporting them as a hole. As this call only expects to walk user address space, make it walk 0 to 'highest_vm_end'. Link: http://lkml.kernel.org/r/1472655792-22439-1-git-send-email-james.morse@arm.comSigned-off-by: NJames Morse <james.morse@arm.com> Acked-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Tim Chen 提交于
In current kernel code, we only call node_set_state(cpu_to_node(cpu), N_CPU) when a cpu is hot plugged. But we do not set the node state for N_CPU when the cpus are brought online during boot. So this could lead to failure when we check to see if a node contains cpu with node_state(node_id, N_CPU). One use case is in the node_reclaime function: /* * Only run node reclaim on the local node or on nodes that do * not * have associated processors. This will favor the local * processor * over remote processors and spread off node memory allocations * as wide as possible. */ if (node_state(pgdat->node_id, N_CPU) && pgdat->node_id != numa_node_id()) return NODE_RECLAIM_NOSCAN; I instrumented the kernel to call this function after boot and it always returns 0 on a x86 desktop machine until I apply the attached patch. int num_cpu_node(void) { int i, nr_cpu_nodes = 0; for_each_node(i) { if (node_state(i, N_CPU)) ++ nr_cpu_nodes; } return nr_cpu_nodes; } Fix this by checking each node for online CPU when we initialize vmstat that's responsible for maintaining node state. Link: http://lkml.kernel.org/r/20160829175922.GA21775@linux.intel.comSigned-off-by: NTim Chen <tim.c.chen@linux.intel.com> Acked-by: NDavid Rientjes <rientjes@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: <Huang@linux.intel.com> Cc: Ying <ying.huang@intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Toshi Kani 提交于
To support DAX pmd mappings with unmodified applications, filesystems need to align an mmap address by the pmd size. Call thp_get_unmapped_area() from f_op->get_unmapped_area. Note, there is no change in behavior for a non-DAX file. Link: http://lkml.kernel.org/r/1472497881-9323-3-git-send-email-toshi.kani@hpe.comSigned-off-by: NToshi Kani <toshi.kani@hpe.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.cz> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Toshi Kani 提交于
When CONFIG_FS_DAX_PMD is set, DAX supports mmap() using pmd page size. This feature relies on both mmap virtual address and FS block (i.e. physical address) to be aligned by the pmd page size. Users can use mkfs options to specify FS to align block allocations. However, aligning mmap address requires code changes to existing applications for providing a pmd-aligned address to mmap(). For instance, fio with "ioengine=mmap" performs I/Os with mmap() [1]. It calls mmap() with a NULL address, which needs to be changed to provide a pmd-aligned address for testing with DAX pmd mappings. Changing all applications that call mmap() with NULL is undesirable. Add thp_get_unmapped_area(), which can be called by filesystem's get_unmapped_area to align an mmap address by the pmd size for a DAX file. It calls the default handler, mm->get_unmapped_area(), to find a range and then aligns it for a DAX file. The patch is based on Matthew Wilcox's change that allows adding support of the pud page size easily. [1]: https://github.com/axboe/fio/blob/master/engines/mmap.c Link: http://lkml.kernel.org/r/1472497881-9323-2-git-send-email-toshi.kani@hpe.comSigned-off-by: NToshi Kani <toshi.kani@hpe.com> Reviewed-by: NDan Williams <dan.j.williams@intel.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.cz> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Simon Guo 提交于
This patch will randomly perform mlock/mlock2 on a given memory region, and verify the RLIMIT_MEMLOCK limitation works properly. Suggested-by: NDavid Rientjes <rientjes@google.com> Link: http://lkml.kernel.org/r/1473325970-11393-4-git-send-email-wei.guo.simon@gmail.comSigned-off-by: NSimon Guo <wei.guo.simon@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Simon Guo <wei.guo.simon@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Thierry Reding <treding@nvidia.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Simon Guo 提交于
Function seek_to_smaps_entry() can be useful for other selftest functionalities, so move it out to header file. Link: http://lkml.kernel.org/r/1473325970-11393-3-git-send-email-wei.guo.simon@gmail.comSigned-off-by: NSimon Guo <wei.guo.simon@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Simon Guo <wei.guo.simon@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Thierry Reding <treding@nvidia.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Simon Guo 提交于
This patch adds mlock() test for multiple invocation on the same address area, and verify it doesn't mess the rlimit mlock limitation. Link: http://lkml.kernel.org/r/1472554781-9835-5-git-send-email-wei.guo.simon@gmail.comSigned-off-by: NSimon Guo <wei.guo.simon@gmail.com> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Simon Guo <wei.guo.simon@gmail.com> Cc: Thierry Reding <treding@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Simon Guo 提交于
To prepare mlock2.h whose functionality will be reused. Link: http://lkml.kernel.org/r/1472554781-9835-4-git-send-email-wei.guo.simon@gmail.comSigned-off-by: NSimon Guo <wei.guo.simon@gmail.com> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Simon Guo <wei.guo.simon@gmail.com> Cc: Thierry Reding <treding@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Simon Guo 提交于
When one vma was with flag VM_LOCKED|VM_LOCKONFAULT (by invoking mlock2(,MLOCK_ONFAULT)), it can again be populated with mlock() with VM_LOCKED flag only. There is a hole in mlock_fixup() which increase mm->locked_vm twice even the two operations are on the same vma and both with VM_LOCKED flags. The issue can be reproduced by following code: mlock2(p, 1024 * 64, MLOCK_ONFAULT); //VM_LOCKED|VM_LOCKONFAULT mlock(p, 1024 * 64); //VM_LOCKED Then check the increase VmLck field in /proc/pid/status(to 128k). When vma is set with different vm_flags, and the new vm_flags is with VM_LOCKED, it is not necessarily be a "new locked" vma. This patch corrects this bug by prevent mm->locked_vm from increment when old vm_flags is already VM_LOCKED. Link: http://lkml.kernel.org/r/1472554781-9835-3-git-send-email-wei.guo.simon@gmail.comSigned-off-by: NSimon Guo <wei.guo.simon@gmail.com> Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Simon Guo <wei.guo.simon@gmail.com> Cc: Thierry Reding <treding@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Simon Guo 提交于
In do_mlock(), the check against locked memory limitation has a hole which will fail following cases at step 3): 1) User has a memory chunk from addressA with 50k, and user mem lock rlimit is 64k. 2) mlock(addressA, 30k) 3) mlock(addressA, 40k) The 3rd step should have been allowed since the 40k request is intersected with the previous 30k at step 2), and the 3rd step is actually for mlock on the extra 10k memory. This patch checks vma to caculate the actual "new" mlock size, if necessary, and ajust the logic to fix this issue. [akpm@linux-foundation.org: clean up comment layout] [wei.guo.simon@gmail.com: correct a typo in count_mm_mlocked_page_nr()] Link: http://lkml.kernel.org/r/1473325970-11393-2-git-send-email-wei.guo.simon@gmail.com Link: http://lkml.kernel.org/r/1472554781-9835-2-git-send-email-wei.guo.simon@gmail.comSigned-off-by: NSimon Guo <wei.guo.simon@gmail.com> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Simon Guo <wei.guo.simon@gmail.com> Cc: Thierry Reding <treding@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Michal Hocko 提交于
Since the lumpy reclaim is gone there is no source of higher order pages if CONFIG_COMPACTION=n except for the order-0 pages reclaim which is unreliable for that purpose to say the least. Hitting an OOM for !costly higher order requests is therefore all not that hard to imagine. We are trying hard to not invoke OOM killer as much as possible but there is simply no reliable way to detect whether more reclaim retries make sense. Disabling COMPACTION is not widespread but it seems that some users might have disable the feature without realizing full consequences (mostly along with disabling THP because compaction used to be THP mainly thing). This patch just adds a note if the OOM killer was triggered by higher order request with compaction disabled. This will help us identifying possible misconfiguration right from the oom report which is easier than to always keep in mind that somebody might have disabled COMPACTION without a good reason. Link: http://lkml.kernel.org/r/20160830111632.GD23963@dhcp22.suse.czSigned-off-by: NMichal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Huang Ying 提交于
File pages use a set of radix tree tags (DIRTY, TOWRITE, WRITEBACK, etc.) to accelerate finding the pages with a specific tag in the radix tree during inode writeback. But for anonymous pages in the swap cache, there is no inode writeback. So there is no need to find the pages with some writeback tags in the radix tree. It is not necessary to touch radix tree writeback tags for pages in the swap cache. Per Rik van Riel's suggestion, a new flag AS_NO_WRITEBACK_TAGS is introduced for address spaces which don't need to update the writeback tags. The flag is set for swap caches. It may be used for DAX file systems, etc. With this patch, the swap out bandwidth improved 22.3% (from ~1.2GB/s to ~1.48GBps) in the vm-scalability swap-w-seq test case with 8 processes. The test is done on a Xeon E5 v3 system. The swap device used is a RAM simulated PMEM (persistent memory) device. The improvement comes from the reduced contention on the swap cache radix tree lock. To test sequential swapping out, the test case uses 8 processes, which sequentially allocate and write to the anonymous pages until RAM and part of the swap device is used up. Details of comparison is as follow, base base+patch ---------------- -------------------------- %stddev %change %stddev \ | \ 2506952 ± 2% +28.1% 3212076 ± 7% vm-scalability.throughput 1207402 ± 7% +22.3% 1476578 ± 6% vmstat.swap.so 10.86 ± 12% -23.4% 8.31 ± 16% perf-profile.cycles-pp._raw_spin_lock_irq.__add_to_swap_cache.add_to_swap_cache.add_to_swap.shrink_page_list 10.82 ± 13% -33.1% 7.24 ± 14% perf-profile.cycles-pp._raw_spin_lock_irqsave.__remove_mapping.shrink_page_list.shrink_inactive_list.shrink_zone_memcg 10.36 ± 11% -100.0% 0.00 ± -1% perf-profile.cycles-pp._raw_spin_lock_irqsave.__test_set_page_writeback.bdev_write_page.__swap_writepage.swap_writepage 10.52 ± 12% -100.0% 0.00 ± -1% perf-profile.cycles-pp._raw_spin_lock_irqsave.test_clear_page_writeback.end_page_writeback.page_endio.pmem_rw_page Link: http://lkml.kernel.org/r/1472578089-5560-1-git-send-email-ying.huang@intel.comSigned-off-by: N"Huang, Ying" <ying.huang@intel.com> Acked-by: NRik van Riel <riel@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Shaohua Li <shli@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Tejun Heo <tj@kernel.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 zijun_hu 提交于
In ___alloc_bootmem_node_nopanic(), replace kzalloc() by kzalloc_node() in order to allocate memory within given node preferentially when slab is available Link: http://lkml.kernel.org/r/1f487f12-6af4-5e4f-a28c-1de2361cdcd8@zoho.comSigned-off-by: Nzijun_hu <zijun_hu@htc.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 zijun_hu 提交于
Fix the following bugs: - the same ARCH_LOW_ADDRESS_LIMIT statements are duplicated between header and relevant source - don't ensure ARCH_LOW_ADDRESS_LIMIT perhaps defined by ARCH in asm/processor.h is preferred over default in linux/bootmem.h completely since the former header isn't included by the latter Link: http://lkml.kernel.org/r/e046aeaa-e160-6d9e-dc1b-e084c2fd999f@zoho.comSigned-off-by: Nzijun_hu <zijun_hu@htc.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Srikar Dronamraju 提交于
Currently significant amount of memory is reserved only in kernel booted to capture kernel dump using the fa_dump method. Kernels compiled with CONFIG_DEFERRED_STRUCT_PAGE_INIT will initialize only certain size memory per node. The certain size takes into account the dentry and inode cache sizes. Currently the cache sizes are calculated based on the total system memory including the reserved memory. However such a kernel when booting the same kernel as fadump kernel will not be able to allocate the required amount of memory to suffice for the dentry and inode caches. This results in crashes like Hence only implement arch_reserved_kernel_pages() for CONFIG_FA_DUMP configurations. The amount reserved will be reduced while calculating the large caches and will avoid crashes like the below on large systems such as 32 TB systems. Dentry cache hash table entries: 536870912 (order: 16, 4294967296 bytes) vmalloc: allocation failure, allocated 4097114112 of 17179934720 bytes swapper/0: page allocation failure: order:0, mode:0x2080020(GFP_ATOMIC) CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6-master+ #3 Call Trace: dump_stack+0xb0/0xf0 (unreliable) warn_alloc_failed+0x114/0x160 __vmalloc_node_range+0x304/0x340 __vmalloc+0x6c/0x90 alloc_large_system_hash+0x1b8/0x2c0 inode_init+0x94/0xe4 vfs_caches_init+0x8c/0x13c start_kernel+0x50c/0x578 start_here_common+0x20/0xa8 Link: http://lkml.kernel.org/r/1472476010-4709-4-git-send-email-srikar@linux.vnet.ibm.comSigned-off-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com> Suggested-by: NMel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Srikar Dronamraju 提交于
The total reserved memory in a system is accounted but not available for use use outside mm/memblock.c. By exposing the total reserved memory, systems can better calculate the size of large hashes. Link: http://lkml.kernel.org/r/1472476010-4709-3-git-send-email-srikar@linux.vnet.ibm.comSigned-off-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com> Suggested-by: NMel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Srikar Dronamraju 提交于
Currently arch specific code can reserve memory blocks but alloc_large_system_hash() may not take it into consideration when sizing the hashes. This can lead to bigger hash than required and lead to no available memory for other purposes. This is specifically true for systems with CONFIG_DEFERRED_STRUCT_PAGE_INIT enabled. One approach to solve this problem would be to walk through the memblock regions and calculate the available memory and base the size of hash system on the available memory. The other approach would be to depend on the architecture to provide the number of pages that are reserved. This change provides hooks to allow the architecture to provide the required info. Link: http://lkml.kernel.org/r/1472476010-4709-2-git-send-email-srikar@linux.vnet.ibm.comSigned-off-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com> Suggested-by: NMel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Aneesh Kumar K.V 提交于
Use the existing enums instead of hardcoded index when looking at the zonelist. This makes it more readable. No functionality change by this patch. Link: http://lkml.kernel.org/r/1472227078-24852-1-git-send-email-aneesh.kumar@linux.vnet.ibm.comSigned-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: NAnshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Michal Hocko 提交于
oom reaper was skipped for an mm which is shared with the kernel thread (aka use_mm()). The primary concern was that such a kthread might want to read from the userspace memory and see zero page as a result of the oom reaper action. This is no longer a problem after "mm: make sure that kthreads will not refault oom reaped memory" because any attempt to fault in when the MMF_UNSTABLE is set will result in SIGBUS and so the target user should see an error. This means that we can finally allow oom reaper also to tasks which share their mm with kthreads. Link: http://lkml.kernel.org/r/1472119394-11342-10-git-send-email-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Michal Hocko 提交于
There are only few use_mm() users in the kernel right now. Most of them write to the target memory but vhost driver relies on copy_from_user/get_user from a kernel thread context. This makes it impossible to reap the memory of an oom victim which shares the mm with the vhost kernel thread because it could see a zero page unexpectedly and theoretically make an incorrect decision visible outside of the killed task context. To quote Michael S. Tsirkin: : Getting an error from __get_user and friends is handled gracefully. : Getting zero instead of a real value will cause userspace : memory corruption. The vhost kernel thread is bound to an open fd of the vhost device which is not tight to the mm owner life cycle in general. The device fd can be inherited or passed over to another process which means that we really have to be careful about unexpected memory corruption because unlike for normal oom victims the result will be visible outside of the oom victim context. Make sure that no kthread context (users of use_mm) can ever see corrupted data because of the oom reaper and hook into the page fault path by checking MMF_UNSTABLE mm flag. __oom_reap_task_mm will set the flag before it starts unmapping the address space while the flag is checked after the page fault has been handled. If the flag is set then SIGBUS is triggered so any g-u-p user will get a error code. Regular tasks do not need this protection because all which share the mm are killed when the mm is reaped and so the corruption will not outlive them. This patch shouldn't have any visible effect at this moment because the OOM killer doesn't invoke oom reaper for tasks with mm shared with kthreads yet. Link: http://lkml.kernel.org/r/1472119394-11342-9-git-send-email-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Acked-by: N"Michael S. Tsirkin" <mst@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Tetsuo Handa 提交于
There are no users of exit_oom_victim on !current task anymore so enforce the API to always work on the current. Link: http://lkml.kernel.org/r/1472119394-11342-8-git-send-email-mhocko@kernel.orgSigned-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: NMichal Hocko <mhocko@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Michal Hocko 提交于
Commit 74070542 ("oom, suspend: fix oom_reaper vs. oom_killer_disable race") has workaround an existing race between oom_killer_disable and oom_reaper by adding another round of try_to_freeze_tasks after the oom killer was disabled. This was the easiest thing to do for a late 4.7 fix. Let's fix it properly now. After "oom: keep mm of the killed task available" we no longer have to call exit_oom_victim from the oom reaper because we have stable mm available and hide the oom_reaped mm by MMF_OOM_SKIP flag. So let's remove exit_oom_victim and the race described in the above commit doesn't exist anymore if. Unfortunately this alone is not sufficient for the oom_killer_disable usecase because now we do not have any reliable way to reach exit_oom_victim (the victim might get stuck on a way to exit for an unbounded amount of time). OOM killer can cope with that by checking mm flags and move on to another victim but we cannot do the same for oom_killer_disable as we would lose the guarantee of no further interference of the victim with the rest of the system. What we can do instead is to cap the maximum time the oom_killer_disable waits for victims. The only current user of this function (pm suspend) already has a concept of timeout for back off so we can reuse the same value there. Let's drop set_freezable for the oom_reaper kthread because it is no longer needed as the reaper doesn't wake or thaw any processes. Link: http://lkml.kernel.org/r/1472119394-11342-7-git-send-email-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Michal Hocko 提交于
After "oom: keep mm of the killed task available" we can safely detect an oom victim by checking task->signal->oom_mm so we do not need the signal_struct counter anymore so let's get rid of it. This alone wouldn't be sufficient for nommu archs because exit_oom_victim doesn't hide the process from the oom killer anymore. We can, however, mark the mm with a MMF flag in __mmput. We can reuse MMF_OOM_REAPED and rename it to a more generic MMF_OOM_SKIP. Link: http://lkml.kernel.org/r/1472119394-11342-6-git-send-email-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Michal Hocko 提交于
Lockdep complains that __mmdrop is not safe from the softirq context: ================================= [ INFO: inconsistent lock state ] 4.6.0-oomfortification2-00011-geeb3eadeab96-dirty #949 Tainted: G W --------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. swapper/1/0 [HC0[0]:SC1[1]:HE1:SE0] takes: (pgd_lock){+.?...}, at: pgd_free+0x19/0x6b {SOFTIRQ-ON-W} state was registered at: __lock_acquire+0xa06/0x196e lock_acquire+0x139/0x1e1 _raw_spin_lock+0x32/0x41 __change_page_attr_set_clr+0x2a5/0xacd change_page_attr_set_clr+0x16f/0x32c set_memory_nx+0x37/0x3a free_init_pages+0x9e/0xc7 alternative_instructions+0xa2/0xb3 check_bugs+0xe/0x2d start_kernel+0x3ce/0x3ea x86_64_start_reservations+0x2a/0x2c x86_64_start_kernel+0x17a/0x18d irq event stamp: 105916 hardirqs last enabled at (105916): free_hot_cold_page+0x37e/0x390 hardirqs last disabled at (105915): free_hot_cold_page+0x2c1/0x390 softirqs last enabled at (105878): _local_bh_enable+0x42/0x44 softirqs last disabled at (105879): irq_exit+0x6f/0xd1 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(pgd_lock); <Interrupt> lock(pgd_lock); *** DEADLOCK *** 1 lock held by swapper/1/0: #0: (rcu_callback){......}, at: rcu_process_callbacks+0x390/0x800 stack backtrace: CPU: 1 PID: 0 Comm: swapper/1 Tainted: G W 4.6.0-oomfortification2-00011-geeb3eadeab96-dirty #949 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 Call Trace: <IRQ> print_usage_bug.part.25+0x259/0x268 mark_lock+0x381/0x567 __lock_acquire+0x993/0x196e lock_acquire+0x139/0x1e1 _raw_spin_lock+0x32/0x41 pgd_free+0x19/0x6b __mmdrop+0x25/0xb9 __put_task_struct+0x103/0x11e delayed_put_task_struct+0x157/0x15e rcu_process_callbacks+0x660/0x800 __do_softirq+0x1ec/0x4d5 irq_exit+0x6f/0xd1 smp_apic_timer_interrupt+0x42/0x4d apic_timer_interrupt+0x8e/0xa0 <EOI> arch_cpu_idle+0xf/0x11 default_idle_call+0x32/0x34 cpu_startup_entry+0x20c/0x399 start_secondary+0xfe/0x101 More over commit a79e53d8 ("x86/mm: Fix pgd_lock deadlock") was explicit about pgd_lock not to be called from the irq context. This means that __mmdrop called from free_signal_struct has to be postponed to a user context. We already have a similar mechanism for mmput_async so we can use it here as well. This is safe because mm_count is pinned by mm_users. This fixes bug introduced by "oom: keep mm of the killed task available" Link: http://lkml.kernel.org/r/1472119394-11342-5-git-send-email-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Michal Hocko 提交于
oom_reap_task has to call exit_oom_victim in order to make sure that the oom vicim will not block the oom killer for ever. This is, however, opening new problems (e.g oom_killer_disable exclusion - see commit 74070542 ("oom, suspend: fix oom_reaper vs. oom_killer_disable race")). exit_oom_victim should be only called from the victim's context ideally. One way to achieve this would be to rely on per mm_struct flags. We already have MMF_OOM_REAPED to hide a task from the oom killer since "mm, oom: hide mm which is shared with kthread or global init". The problem is that the exit path: do_exit exit_mm tsk->mm = NULL; mmput __mmput exit_oom_victim doesn't guarantee that exit_oom_victim will get called in a bounded amount of time. At least exit_aio depends on IO which might get blocked due to lack of memory and who knows what else is lurking there. This patch takes a different approach. We remember tsk->mm into the signal_struct and bind it to the signal struct life time for all oom victims. __oom_reap_task_mm as well as oom_scan_process_thread do not have to rely on find_lock_task_mm anymore and they will have a reliable reference to the mm struct. As a result all the oom specific communication inside the OOM killer can be done via tsk->signal->oom_mm. Increasing the signal_struct for something as unlikely as the oom killer is far from ideal but this approach will make the code much more reasonable and long term we even might want to move task->mm into the signal_struct anyway. In the next step we might want to make the oom killer exclusion and access to memory reserves completely independent which would be also nice. Link: http://lkml.kernel.org/r/1472119394-11342-4-git-send-email-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Tetsuo Handa 提交于
"mm, oom_reaper: do not attempt to reap a task twice" tried to give the OOM reaper one more chance to retry using MMF_OOM_NOT_REAPABLE flag. But the usefulness of the flag is rather limited and actually never shown in practice. If the flag is set, it means that the holder of mm->mmap_sem cannot call up_write() due to presumably being blocked at unkillable wait waiting for other thread's memory allocation. But since one of threads sharing that mm will queue that mm immediately via task_will_free_mem() shortcut (otherwise, oom_badness() will select the same mm again due to oom_score_adj value unchanged), retrying MMF_OOM_NOT_REAPABLE mm is unlikely helpful. Let's always set MMF_OOM_REAPED. Link: http://lkml.kernel.org/r/1472119394-11342-3-git-send-email-mhocko@kernel.orgSigned-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: NMichal Hocko <mhocko@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Tetsuo Handa 提交于
Patch series "fortify oom killer even more", v2. This patch (of 9): __oom_reap_task() can be simplified a bit if it receives a valid mm from oom_reap_task() which also uses that mm when __oom_reap_task() failed. We can drop one find_lock_task_mm() call and also make the __oom_reap_task() code flow easier to follow. Moreover, this will make later patch in the series easier to review. Pinning mm's mm_count for longer time is not really harmful because this will not pin much memory. This patch doesn't introduce any functional change. Link: http://lkml.kernel.org/r/1472119394-11342-2-git-send-email-mhocko@kernel.orgSigned-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: NMichal Hocko <mhocko@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Huang Ying 提交于
This is a code clean up patch without functionality changes. The swap_cluster_list data structure and its operations are introduced to provide some better encapsulation for the free cluster and discard cluster list operations. This avoid some code duplication, improved the code readability, and reduced the total line number. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/1472067356-16004-1-git-send-email-ying.huang@intel.comSigned-off-by: N"Huang, Ying" <ying.huang@intel.com> Acked-by: NMinchan Kim <minchan@kernel.org> Acked-by: NRik van Riel <riel@redhat.com> Cc: Tim Chen <tim.c.chen@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Shaohua Li <shli@kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Alexey Dobriyan 提交于
Current code doesn't count first FIND operation after VMA cache flush (which happen surprisingly often) artificially increasing cache hit ratio. On my regular setup the difference is: Before After ========================================================== * boot, login into KDE vmacache_find_calls 446216 vmacache_find_calls 492741 vmacache_find_hits 277596 vmacache_find_hits 276096 ~62.2% ~56.0% * rebuild kernel (no changes to code, usual config) vmacache_find_calls 1943007 vmacache_find_calls 2083718 vmacache_find_hits 1246123 vmacache_find_hits 1244146 ~64.1% ~59.7% * rebuild kernel (full rebuild, usual config) vmacache_find_calls 32163155 vmacache_find_calls 33677183 vmacache_find_hits 27889956 vmacache_find_hits 27877591 ~88.2% ~84.3% Total: ~4% cache hit ratio. If someone is counting _relative_ cache _miss_ ratio, misreporting is much higher. Link: http://lkml.kernel.org/r/20160822225009.GA3934@p183.telecom.bySigned-off-by: NAlexey Dobriyan <adobriyan@gmail.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 James Morse 提交于
Modify the comment describing struct mm_walk->test_walk()s behaviour to match the comment on walk_page_test() and the behaviour of walk_page_vma(). Fixes: fafaa426 ("pagewalk: improve vma handling") Link: http://lkml.kernel.org/r/1471622518-21980-1-git-send-email-james.morse@arm.comSigned-off-by: NJames Morse <james.morse@arm.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Bart Van Assche 提交于
If a fatal signal has been received, fail immediately instead of trying to read more data. If wait_on_page_locked_killable() was interrupted then this page is most likely is not PageUptodate() and in this case do_generic_file_read() will fail after lock_page_killable(). See also commit ebded027 ("mm: filemap: avoid unnecessary calls to lock_page when waiting for IO to complete during a read") [oleg@redhat.com: changelog addition] Link: http://lkml.kernel.org/r/63068e8e-8bee-b208-8441-a3c39a9d9eb6@sandisk.comSigned-off-by: NBart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: NJan Kara <jack@suse.cz> Acked-by: NOleg Nesterov <oleg@redhat.com> Acked-by: NMichal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joonsoo Kim 提交于
There is a memory waste problem if we define field on struct page_ext by hard-coding. Entry size of struct page_ext includes the size of those fields even if it is disabled at runtime. Now, extra memory request at runtime is possible so page_owner don't need to define it's own fields by hard-coding. This patch removes hard-coded define and uses extra memory for storing page_owner information in page_owner. Most of code are just mechanical changes. Link: http://lkml.kernel.org/r/1471315879-32294-7-git-send-email-iamjoonsoo.kim@lge.comSigned-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joonsoo Kim 提交于
Until now, if some page_ext users want to use it's own field on page_ext, it should be defined in struct page_ext by hard-coding. It has a problem that wastes memory in following situation. struct page_ext { #ifdef CONFIG_A int a; #endif #ifdef CONFIG_B int b; #endif }; Assume that kernel is built with both CONFIG_A and CONFIG_B. Even if we enable feature A and doesn't enable feature B at runtime, each entry of struct page_ext takes two int rather than one int. It's undesirable result so this patch tries to fix it. To solve above problem, this patch implements to support extra space allocation at runtime. When need() callback returns true, it's extra memory requirement is summed to entry size of page_ext. Also, offset for each user's extra memory space is returned. With this offset, user can use this extra space and there is no need to define needed field on page_ext by hard-coding. This patch only implements an infrastructure. Following patch will use it for page_owner which is only user having it's own fields on page_ext. Link: http://lkml.kernel.org/r/1471315879-32294-6-git-send-email-iamjoonsoo.kim@lge.comSigned-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joonsoo Kim 提交于
Here, 'offset' means entry index in page_ext array. Following patch will use 'offset' for field offset in each entry so rename current 'offset' to prevent confusion. Link: http://lkml.kernel.org/r/1471315879-32294-5-git-send-email-iamjoonsoo.kim@lge.comSigned-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joonsoo Kim 提交于
There is no reason that page_owner specific function resides on vmstat.c. Link: http://lkml.kernel.org/r/1471315879-32294-4-git-send-email-iamjoonsoo.kim@lge.comSigned-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joonsoo Kim 提交于
What debug_pagealloc does is just mapping/unmapping page table. Basically, it doesn't need additional memory space to memorize something. But, with guard page feature, it requires additional memory to distinguish if the page is for guard or not. Guard page is only used when debug_guardpage_minorder is non-zero so this patch removes additional memory allocation (page_ext) if debug_guardpage_minorder is zero. It saves memory if we just use debug_pagealloc and not guard page. Link: http://lkml.kernel.org/r/1471315879-32294-3-git-send-email-iamjoonsoo.kim@lge.comSigned-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Joonsoo Kim 提交于
Patch series "Reduce memory waste by page extension user". This patchset tries to reduce memory waste by page extension user. First case is architecture supported debug_pagealloc. It doesn't requires additional memory if guard page isn't used. 8 bytes per page will be saved in this case. Second case is related to page owner feature. Until now, if page_ext users want to use it's own fields on page_ext, fields should be defined in struct page_ext by hard-coding. It has a following problem. struct page_ext { #ifdef CONFIG_A int a; #endif #ifdef CONFIG_B int b; #endif }; Assume that kernel is built with both CONFIG_A and CONFIG_B. Even if we enable feature A and doesn't enable feature B at runtime, each entry of struct page_ext takes two int rather than one int. It's undesirable waste so this patch tries to reduce it. By this patchset, we can save 20 bytes per page dedicated for page owner feature in some configurations. This patch (of 6): We can make code clean by moving decision condition for set_page_guard() into set_page_guard() itself. It will help code readability. There is no functional change. Link: http://lkml.kernel.org/r/1471315879-32294-2-git-send-email-iamjoonsoo.kim@lge.comSigned-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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