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* uksm: remove Mtk aksm & uksm (because its fugly)Mister Oyster2017-07-041-144/+1
| | | | | | | | | | | | | | | | Revert "KSM: mediatek: implement Adaptive KSM" Revert "mm: uksm: fix maybe-uninitialized warning" Revert "UKSM: Add Governors for Higher CPU usage (HighCPU) for more merging, and low cpu usage (Battery) for less battery drain" Revert "uksm: use deferrable timer" Revert "mm: limit UKSM sleep time instead of failing" Revert "uksm: Fix warning" Revert "uksm: clean up and remove some (no)inlines" Revert "uksm: modify ema logic and tidy up" Revert "uksm: enhancements and cleanups" Revert "uksm: squashed fixups" Revert "UKSM: cast variable as const" Revert "UKSM: remove U64_MAX definition" Revert "add uksm 0.1.2.3 for v3.10 .ge.46.patch"
* mm,ksm: add __GFP_HIGH to the allocation in alloc_stable_node()zhong jiang2017-04-111-1/+6
| | | | | | | | | | | | | | | | | | | | According to Hugh's suggestion, alloc_stable_node() with GFP_KERNEL can in rare cases cause a hung task warning. At present, if alloc_stable_node() allocation fails, two break_cows may want to allocate a couple of pages, and the issue will come up when free memory is under pressure. We fix it by adding __GFP_HIGH to GFP, to grant access to memory reserves, increasing the likelihood of allocation success. [akpm@linux-foundation.org: tweak comment] Link: http://lkml.kernel.org/r/1474354484-58233-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang <zhongjiang@huawei.com> Suggested-by: Hugh Dickins <hughd@google.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm,ksm: fix endless looping in allocating memory when ksm enablezhong jiang2017-04-111-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I hit the following hung task when runing a OOM LTP test case with 4.1 kernel. Call trace: [<ffffffc000086a88>] __switch_to+0x74/0x8c [<ffffffc000a1bae0>] __schedule+0x23c/0x7bc [<ffffffc000a1c09c>] schedule+0x3c/0x94 [<ffffffc000a1eb84>] rwsem_down_write_failed+0x214/0x350 [<ffffffc000a1e32c>] down_write+0x64/0x80 [<ffffffc00021f794>] __ksm_exit+0x90/0x19c [<ffffffc0000be650>] mmput+0x118/0x11c [<ffffffc0000c3ec4>] do_exit+0x2dc/0xa74 [<ffffffc0000c46f8>] do_group_exit+0x4c/0xe4 [<ffffffc0000d0f34>] get_signal+0x444/0x5e0 [<ffffffc000089fcc>] do_signal+0x1d8/0x450 [<ffffffc00008a35c>] do_notify_resume+0x70/0x78 The oom victim cannot terminate because it needs to take mmap_sem for write while the lock is held by ksmd for read which loops in the page allocator ksm_do_scan scan_get_next_rmap_item down_read get_next_rmap_item alloc_rmap_item #ksmd will loop permanently. There is no way forward because the oom victim cannot release any memory in 4.1 based kernel. Since 4.6 we have the oom reaper which would solve this problem because it would release the memory asynchronously. Nevertheless we can relax alloc_rmap_item requirements and use __GFP_NORETRY because the allocation failure is acceptable as ksm_do_scan would just retry later after the lock got dropped. Such a patch would be also easy to backport to older stable kernels which do not have oom_reaper. While we are at it add GFP_NOWARN so the admin doesn't have to be alarmed by the allocation failure. Link: http://lkml.kernel.org/r/1474165570-44398-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang <zhongjiang@huawei.com> Suggested-by: Hugh Dickins <hughd@google.com> Suggested-by: Michal Hocko <mhocko@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ksm: fix conflict between mmput and scan_get_next_rmap_itemZhou Chengming2017-04-111-5/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A concurrency issue about KSM in the function scan_get_next_rmap_item. task A (ksmd): |task B (the mm's task): | mm = slot->mm; | down_read(&mm->mmap_sem); | | ... | | spin_lock(&ksm_mmlist_lock); | | ksm_scan.mm_slot go to the next slot; | | spin_unlock(&ksm_mmlist_lock); | |mmput() -> | ksm_exit(): | |spin_lock(&ksm_mmlist_lock); |if (mm_slot && ksm_scan.mm_slot != mm_slot) { | if (!mm_slot->rmap_list) { | easy_to_free = 1; | ... | |if (easy_to_free) { | mmdrop(mm); | ... | |So this mm_struct may be freed in the mmput(). | up_read(&mm->mmap_sem); | As we can see above, the ksmd thread may access a mm_struct that already been freed to the kmem_cache. Suppose a fork will get this mm_struct from the kmem_cache, the ksmd thread then call up_read(&mm->mmap_sem), will cause mmap_sem.count to become -1. As suggested by Andrea Arcangeli, unmerge_and_remove_all_rmap_items has the same SMP race condition, so fix it too. My prev fix in function scan_get_next_rmap_item will introduce a different SMP race condition, so just invert the up_read/spin_unlock order as Andrea Arcangeli said. Link: http://lkml.kernel.org/r/1462708815-31301-1-git-send-email-zhouchengming1@huawei.com Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com> Suggested-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Geliang Tang <geliangtang@163.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Ding Tianhong <dingtianhong@huawei.com> Cc: Li Bin <huawei.libin@huawei.com> Cc: Zhen Lei <thunder.leizhen@huawei.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/ksm.c: mark stable page dirtyMinchan Kim2017-04-111-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The MADV_FREE patchset changes page reclaim to simply free a clean anonymous page with no dirty ptes, instead of swapping it out; but KSM uses clean write-protected ptes to reference the stable ksm page. So be sure to mark that page dirty, so it's never mistakenly discarded. [hughd@google.com: adjusted comments] Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Hugh Dickins <hughd@google.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Shaohua Li <shli@kernel.org> Cc: <yalin.wang2010@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Gang <gang.chen.5i5j@gmail.com> Cc: Chris Zankel <chris@zankel.net> Cc: Daniel Micay <danielmicay@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Jason Evans <je@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mika Penttil <mika.penttila@nextfour.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Rik van Riel <riel@redhat.com> Cc: Roland Dreier <roland@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Shaohua Li <shli@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/ksm.c: use list_for_each_entry_safeGeliang Tang2017-04-111-13/+7
| | | | | | | | | | Use list_for_each_entry_safe() instead of list_for_each_safe() to simplify the code. Signed-off-by: Geliang Tang <geliangtang@163.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ksm: unstable_tree_search_insert error checking cleanupAndrea Arcangeli2017-04-111-2/+3
| | | | | | | | | | | | | | | get_mergeable_page() can only return NULL (also in case of errors) or the pinned mergeable page. It can't return an error different than NULL. This optimizes away the unnecessary error check. Add a return after the "out:" label in the callee to make it more readable. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Petr Holasek <pholasek@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ksm: use find_mergeable_vma in try_to_merge_with_ksm_pageAndrea Arcangeli2017-04-111-6/+2
| | | | | | | | | | | | | | Doing the VM_MERGEABLE check after the page == kpage check won't provide any meaningful benefit. The !vma->anon_vma check of find_mergeable_vma is the only superfluous bit in using find_mergeable_vma because the !PageAnon check of try_to_merge_one_page() implicitly checks for that, but it still looks cleaner to share the same find_mergeable_vma(). Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Petr Holasek <pholasek@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ksm: use the helper method to do the hlist_empty checkAndrea Arcangeli2017-04-111-1/+1
| | | | | | | | | | | | This just uses the helper function to cleanup the assumption on the hlist_node internals. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Petr Holasek <pholasek@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Joe Maples <joe@frap129.org>
* ksm: don't fail stable tree lookups if walking over stale stable_nodesAndrea Arcangeli2017-04-111-5/+27
| | | | | | | | | | | | | | | | | | | | | | | The stable_nodes can become stale at any time if the underlying pages gets freed. The stable_node gets collected and removed from the stable rbtree if that is detected during the rbtree lookups. Don't fail the lookup if running into stale stable_nodes, just restart the lookup after collecting the stale stable_nodes. Otherwise the CPU spent in the preparation stage is wasted and the lookup must be repeated at the next loop potentially failing a second time in a second stale stable_node. If we don't prune aggressively we delay the merging of the unstable node candidates and at the same time we delay the freeing of the stale stable_nodes. Keeping stale stable_nodes around wastes memory and it can't provide any benefit. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Petr Holasek <pholasek@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Joe Maples <joe@frap129.org>
* ksm: add cond_resched() to the rmap_walksAndrea Arcangeli2017-04-111-0/+2
| | | | | | | | | | | | | | | While at it add it to the file and anon walks too. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Petr Holasek <pholasek@redhat.com> Acked-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Joe Maples <joe@frap129.org> Conflicts: mm/rmap.c
* ksm: Don't bug on pmd_trans_hugeJoe Maples2017-04-111-1/+0
| | | | Signed-off-by: Joe Maples <joe@frap129.org>
* mm: ksm use pr_err instead of printkPaul McQuade2017-04-111-2/+2
| | | | | | | | | WARNING: Prefer: pr_err(... to printk(KERN_ERR ... [akpm@linux-foundation.org: remove KERN_ERR] Signed-off-by: Paul McQuade <paulmcquad@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* KSM: mediatek: implement Adaptive KSMAnmin Hsu2016-12-251-1/+144
| | | | | | | | | | | | | | [Detail] implement Adaptive KSM [Solution] implement Adaptive KSM [Feature] Adaptive KSM MTK-Commit-Id: 39cab34ba6273f932a61698513284383dc6bb3bc Change-Id: I844434ef2d1159fea0f0c265d05a0e118cf618f6 Signed-off-by: Casper Li <casper.li@mediatek.com> CR-Id: ALPS02298405
* mm: replace strict_strtoul() with kstrtoul()Jingoo Han2016-09-281-3/+3
| | | | | | | | | | The use of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: W4TCH0UT <ateekujjawal@gmail.com>
* 3.10.75 -> 3.10.76Jan Engelmohr2016-08-261-1/+1
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* first commitMeizu OpenSource2016-08-151-0/+2443