- 03 May, 2017 40 commits
-
-
Sangwoo Park authored
In page_same_filled function, all elements in the page is compared with next index value. The current comparison routine compares the (i)th and (i+1)th values of the page. In this case, two load operaions occur for each comparison. But if we store first value of the page stores at 'val' variable and using it to compare with others, the load opearation is reduced. It reduce load operation per page by up to 64times. Link: http://lkml.kernel.org/r/1488428104-7257-1-git-send-email-sangwoo2.park@lge.comSigned-off-by:
Sangwoo Park <sangwoo2.park@lge.com> Reviewed-by:
Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by:
Minchan Kim <minchan@kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Minchan Kim authored
The zram_free_page already handles NULL handle case and same page so use it to reduce error probability. (Acutaully, I made a mistake when I handled same page feature) Link: http://lkml.kernel.org/r/1492052365-16169-7-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
With element, sometime I got confused handle and element access. It might be my bad but I think it's time to introduce accessor to prevent future idiot like me. This patch is just clean-up patch so it shouldn't change any behavior. Link: http://lkml.kernel.org/r/1492052365-16169-6-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
It's redundant now. Instead, remove it and use zram structure directly. Link: http://lkml.kernel.org/r/1492052365-16169-5-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
With this clean-up phase, I want to use zram's wrapper function to lock table access which is more consistent with other zram's functions. Link: http://lkml.kernel.org/r/1492052365-16169-4-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
For architecture(PAGE_SIZE > 4K), zram have supported partial IO. However, the mixed code for handling normal/partial IO is too mess, error-prone to modify IO handler functions with upcoming feature so this patch aims for cleaning up zram's IO handling functions. Link: http://lkml.kernel.org/r/1492052365-16169-3-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
Patch series "zram clean up", v2. This patchset aims to clean up zram . [1] clean up multiple pages's bvec handling. [2] clean up partial IO handling [3-6] clean up zram via using accessor and removing pointless structure. With [2-6] applied, we can get a few hundred bytes as well as huge readibility enhance. x86: 708 byte save add/remove: 1/1 grow/shrink: 0/11 up/down: 478/-1186 (-708) function old new delta zram_special_page_read - 478 +478 zram_reset_device 317 314 -3 mem_used_max_store 131 128 -3 compact_store 96 93 -3 mm_stat_show 203 197 -6 zram_add 719 712 -7 zram_slot_free_notify 229 214 -15 zram_make_request 819 803 -16 zram_meta_free 128 111 -17 zram_free_page 180 151 -29 disksize_store 432 361 -71 zram_decompress_page.isra 504 - -504 zram_bvec_rw 2592 2080 -512 Total: Before=25350773, After=25350065, chg -0.00% ppc64: 231 byte save add/remove: 2/0 grow/shrink: 1/9 up/down: 681/-912 (-231) function old new delta zram_special_page_read - 480 +480 zram_slot_lock - 200 +200 vermagic 39 40 +1 mm_stat_show 256 248 -8 zram_meta_free 200 184 -16 zram_add 944 912 -32 zram_free_page 348 308 -40 disksize_store 572 492 -80 zram_decompress_page 664 564 -100 zram_slot_free_notify 292 160 -132 zram_make_request 1132 1000 -132 zram_bvec_rw 2768 2396 -372 Total: Before=17565825, After=17565594, chg -0.00% This patch (of 6): Johannes Thumshirn reported system goes the panic when using NVMe over Fabrics loopback target with zram. The reason is zram expects each bvec in bio contains a single page but nvme can attach a huge bulk of pages attached to the bio's bvec so that zram's index arithmetic could be wrong so that out-of-bound access makes system panic. [1] in mainline solved solved the problem by limiting max_sectors with SECTORS_PER_PAGE but it makes zram slow because bio should split with each pages so this patch makes zram aware of multiple pages in a bvec so it could solve without any regression(ie, bio split). [1] 0bc31538, zram: set physical queue limits to avoid array out of bounds accesses Link: http://lkml.kernel.org/r/20170413134057.GA27499@bboxSigned-off-by:Johannes Thumshirn <jthumshirn@suse.de> Tested-by:
-
Tetsuo Handa authored
Commit c0a32fc5 ("mm: more intensive memory corruption debugging") changed to check debug_guardpage_minorder() > 0 when reporting allocation failures. The reasoning was When we use guard page to debug memory corruption, it shrinks available pages to 1/2, 1/4, 1/8 and so on, depending on parameter value. In such case memory allocation failures can be common and printing errors can flood dmesg. If somebody debug corruption, allocation failures are not the things he/she is interested about. but this is misguided. Allocation requests with __GFP_NOWARN flag by definition do not cause flooding of allocation failure messages. Allocation requests with __GFP_NORETRY flag likely also have __GFP_NOWARN flag. Costly allocation requests likely also have __GFP_NOWARN flag. Allocation requests without __GFP_DIRECT_RECLAIM flag likely also have __GFP_NOWARN flag or __GFP_HIGH flag. Non-costly allocation requests with __GFP_DIRECT_RECLAIM flag basically retry forever due to the "too small to fail" memory-allocation rule. Therefore, as a whole, shrinking available pages by debug_guardpage_minorder= kernel boot parameter might cause flooding of OOM killer messages but unlikely causes flooding of allocation failure messages. Let's remove debug_guardpage_minorder() > 0 check which would likely be pointless. Link: http://lkml.kernel.org/r/1491910035-4231-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jpSigned-off-by:
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by:
Michal Hocko <mhocko@suse.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by:
-
Anshuman Khandual authored
It helps to provide page flag description along with the raw value in error paths during soft offline process. From sample experiments Before the patch: soft offline: 0x6100: migration failed 1, type 3ffff800008018 soft offline: 0x7400: migration failed 1, type 3ffff800008018 After the patch: soft offline: 0x5900: migration failed 1, type 3ffff800008018 (uptodate|dirty|head) soft offline: 0x6c00: migration failed 1, type 3ffff800008018 (uptodate|dirty|head) Link: http://lkml.kernel.org/r/20170409023829.10788-1-khandual@linux.vnet.ibm.comSigned-off-by:
Anshuman Khandual <khandual@linux.vnet.ibm.com> Acked-by:
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by:
-
Anshuman Khandual authored
madvise_behavior_valid() should be called before acting upon the behavior parameter. Hence move up the function. This also includes MADV_SOFT_OFFLINE and MADV_HWPOISON options as valid behavior parameter for the system call madvise(). Link: http://lkml.kernel.org/r/20170418052844.24891-1-khandual@linux.vnet.ibm.comSigned-off-by:
David Rientjes <rientjes@google.com> Acked-by:
-
Anshuman Khandual authored
This cleans up handling MADV_SOFT_OFFLINE and MADV_HWPOISON called through madvise() system call. * madvise_memory_failure() was misleading to accommodate handling of both memory_failure() as well as soft_offline_page() functions. Basically it handles memory error injection from user space which can go either way as memory failure or soft offline. Renamed as madvise_inject_error() instead. * Renamed struct page pointer 'p' to 'page'. * pr_info() was essentially printing PFN value but it said 'page' which was misleading. Made the process virtual address explicit. Before the patch: Soft offlining page 0x15e3e at 0x3fff8c230000 Soft offlining page 0x1f3 at 0x3fffa0da0000 Soft offlining page 0x744 at 0x3fff7d200000 Soft offlining page 0x1634d at 0x3fff95e20000 Soft offlining page 0x16349 at 0x3fff95e30000 Soft offlining page 0x1d6 at 0x3fff9e8b0000 Soft offlining page 0x5f3 at 0x3fff91bd0000 Injecting memory failure for page 0x15c8b at 0x3fff83280000 Injecting memory failure for page 0x16190 at 0x3fff83290000 Injecting memory failure for page 0x740 at 0x3fff9a2e0000 Injecting memory failure for page 0x741 at 0x3fff9a2f0000 After the patch: Soft offlining pfn 0x1484e at process virtual address 0x3fff883c0000 Soft offlining pfn 0x1484f at process virtual address 0x3fff883d0000 Soft offlining pfn 0x14850 at process virtual address 0x3fff883e0000 Soft offlining pfn 0x14851 at process virtual address 0x3fff883f0000 Soft offlining pfn 0x14852 at process virtual address 0x3fff88400000 Soft offlining pfn 0x14853 at process virtual address 0x3fff88410000 Soft offlining pfn 0x14854 at process virtual address 0x3fff88420000 Soft offlining pfn 0x1521c at process virtual address 0x3fff6bc70000 Injecting memory failure for pfn 0x10fcf at process virtual address 0x3fff86310000 Injecting memory failure for pfn 0x10fd0 at process virtual address 0x3fff86320000 Injecting memory failure for pfn 0x10fd1 at process virtual address 0x3fff86330000 Injecting memory failure for pfn 0x10fd2 at process virtual address 0x3fff86340000 Injecting memory failure for pfn 0x10fd3 at process virtual address 0x3fff86350000 Injecting memory failure for pfn 0x10fd4 at process virtual address 0x3fff86360000 Injecting memory failure for pfn 0x10fd5 at process virtual address 0x3fff86370000 Link: http://lkml.kernel.org/r/20170410084701.11248-1-khandual@linux.vnet.ibm.comSigned-off-by:
-
Mike Kravetz authored
Adding a brief overview of hugetlbfs reservation design and implementation as an aid to those making code modifications in this area. Link: http://lkml.kernel.org/r/1491586995-13085-1-git-send-email-mike.kravetz@oracle.comSigned-off-by:
Mike Kravetz <mike.kravetz@oracle.com> Acked-by:
Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by:
-
Huang Ying authored
This is a code cleanup patch, no functionality changes. There are 2 unused function prototype in swap.h, they are removed. Link: http://lkml.kernel.org/r/20170405071017.23677-1-ying.huang@intel.comSigned-off-by:
"Huang, Ying" <ying.huang@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by:
-
Johannes Weiner authored
The memory controllers stat function names are awkwardly long and arbitrarily different from the zone and node stat functions. The current interface is named: mem_cgroup_read_stat() mem_cgroup_update_stat() mem_cgroup_inc_stat() mem_cgroup_dec_stat() mem_cgroup_update_page_stat() mem_cgroup_inc_page_stat() mem_cgroup_dec_page_stat() This patch renames it to match the corresponding node stat functions: memcg_page_state() [node_page_state()] mod_memcg_state() [mod_node_state()] inc_memcg_state() [inc_node_state()] dec_memcg_state() [dec_node_state()] mod_memcg_page_state() [mod_node_page_state()] inc_memcg_page_state() [inc_node_page_state()] dec_memcg_page_state() [dec_node_page_state()] Link: http://lkml.kernel.org/r/20170404220148.28338-4-hannes@cmpxchg.orgSigned-off-by:
Johannes Weiner <hannes@cmpxchg.org> Acked-by:
Vladimir Davydov <vdavydov.dev@gmail.com> Acked-by:
-
Johannes Weiner authored
The current duplication is a high-maintenance mess, and it's painful to add new items or query memcg state from the rest of the VM. This increases the size of the stat array marginally, but we should aim to track all these stats on a per-cgroup level anyway. Link: http://lkml.kernel.org/r/20170404220148.28338-3-hannes@cmpxchg.orgSigned-off-by:
-
Johannes Weiner authored
The current duplication is a high-maintenance mess, and it's painful to add new items. This increases the size of the event array, but we'll eventually want most of the VM events tracked on a per-cgroup basis anyway. Link: http://lkml.kernel.org/r/20170404220148.28338-2-hannes@cmpxchg.orgSigned-off-by:
-
Johannes Weiner authored
We only ever count single events, drop the @nr parameter. Rename the function accordingly. Remove low-information kerneldoc. Link: http://lkml.kernel.org/r/20170404220148.28338-1-hannes@cmpxchg.orgSigned-off-by:
-
Johannes Weiner authored
Since commit 59dc76b0 ("mm: vmscan: reduce size of inactive file list") we noticed bigger IO spikes during changes in cache access patterns. The patch in question shrunk the inactive list size to leave more room for the current workingset in the presence of streaming IO. However, workingset transitions that previously happened on the inactive list are now pushed out of memory and incur more refaults to complete. This patch disables active list protection when refaults are being observed. This accelerates workingset transitions, and allows more of the new set to establish itself from memory, without eating into the ability to protect the established workingset during stable periods. The workloads that were measurably affected for us were hit pretty bad by it, with refault/majfault rates doubling and tripling during cache transitions, and the machines sustaining half-hour periods of 100% IO utilization, where they'd previously have sub-minute peaks at 60-90%. Stateful services that handle user data tend to be more conservative with kernel upgrades. As a result we hit most page cache issues with some delay, as was the case here. The severity seemed to warrant a stable tag. Fixes: 59dc76b0 ("mm: vmscan: reduce size of inactive file list") Link: http://lkml.kernel.org/r/20170404220052.27593-1-hannes@cmpxchg.orgSigned-off-by:
-
Anshuman Khandual authored
Commit 091d0d55 ("shm: fix null pointer deref when userspace specifies invalid hugepage size") had replaced MAP_HUGE_MASK with SHM_HUGE_MASK. Though both of them contain the same numeric value of 0x3f, MAP_HUGE_MASK flag sounds more appropriate than the other one in the context. Hence change it back. Link: http://lkml.kernel.org/r/20170404045635.616-1-khandual@linux.vnet.ibm.comSigned-off-by:
Matthew Wilcox <mawilcox@microsoft.com> Acked-by:
Balbir Singh <bsingharora@gmail.com> Acked-by:
-
Michal Hocko authored
Tetsuo has reported that sysrq triggered OOM killer will print a misleading information when no tasks are selected: sysrq: SysRq : Manual OOM execution Out of memory: Kill process 4468 ((agetty)) score 0 or sacrifice child Killed process 4468 ((agetty)) total-vm:43704kB, anon-rss:1760kB, file-rss:0kB, shmem-rss:0kB sysrq: SysRq : Manual OOM execution Out of memory: Kill process 4469 (systemd-cgroups) score 0 or sacrifice child Killed process 4469 (systemd-cgroups) total-vm:10704kB, anon-rss:120kB, file-rss:0kB, shmem-rss:0kB sysrq: SysRq : Manual OOM execution sysrq: OOM request ignored because killer is disabled sysrq: SysRq : Manual OOM execution sysrq: OOM request ignored because killer is disabled sysrq: SysRq : Manual OOM execution sysrq: OOM request ignored because killer is disabled The real reason is that there are no eligible tasks for the OOM killer to select but since commit 7c5f64f8 ("mm: oom: deduplicate victim selection code for memcg and global oom") the semantic of out_of_memory has changed without updating moom_callback. This patch updates moom_callback to tell that no task was eligible which is the case for both oom killer disabled and no eligible tasks. In order to help distinguish first case from the second add printk to both oom_killer_{enable,disable}. This information is useful on its own because it might help debugging potential memory allocation failures. Fixes: 7c5f64f8 ("mm: oom: deduplicate victim selection code for memcg and global oom") Link: http://lkml.kernel.org/r/20170404134705.6361-1-mhocko@kernel.orgSigned-off-by:
-
Mike Rapoport authored
Currently, selftest for userfaultfd is compiled three times: for anonymous, shared and hugetlb memory. Let's combine all the cases into a single executable which will have a command line option for selection of the test type. Link: http://lkml.kernel.org/r/1490869741-5913-1-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by:
Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by:
-
Hao Lee authored
Fix variable name error in comments. No code changes. Link: http://lkml.kernel.org/r/20170403161655.5081-1-haolee.swjtu@gmail.comSigned-off-by:
Hao Lee <haolee.swjtu@gmail.com> Signed-off-by:
-
Tim Chen authored
Add a warning diagnostics to user if we failed to allocate swap slots cache and use it. [akpm@linux-foundation.org: use WARN_ONCE return value, fix grammar in message] Link: http://lkml.kernel.org/r/20170328234827.GA10107@linux.intel.comSigned-off-by:
Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by:
-
Pushkar Jambhlekar authored
It is preferred, and the rest of migrate.h gets it right. Link: http://lkml.kernel.org/r/1490336009-8024-1-git-send-email-pushkar.iit@gmail.comSigned-off-by:
Pushkar Jambhlekar <pushkar.iit@gmail.com> Signed-off-by:
-
Vinayak Menon authored
On SPARSEMEM systems page poisoning is enabled after buddy is up, because of the dependency on page extension init. This causes the pages released by free_all_bootmem not to be poisoned. This either delays or misses the identification of some issues because the pages have to undergo another cycle of alloc-free-alloc for any corruption to be detected. Enable page poisoning early by getting rid of the PAGE_EXT_DEBUG_POISON flag. Since all the free pages will now be poisoned, the flag need not be verified before checking the poison during an alloc. [vinmenon@codeaurora.org: fix Kconfig] Link: http://lkml.kernel.org/r/1490878002-14423-1-git-send-email-vinmenon@codeaurora.org Link: http://lkml.kernel.org/r/1490358246-11001-1-git-send-email-vinmenon@codeaurora.orgSigned-off-by:
Vinayak Menon <vinmenon@codeaurora.org> Acked-by:
Laura Abbott <labbott@redhat.com> Tested-by:
-
Huang Ying authored
Cluster lock is used to protect the swap_cluster_info and corresponding elements in swap_info_struct->swap_map[]. But it is found that now in scan_swap_map_slots(), swap_avail_lock may be acquired when cluster lock is held. This does no good except making the locking more complex and improving the potential locking contention, because the swap_info_struct->lock is used to protect the data structure operated in the code already. Fix this via moving the corresponding operations in scan_swap_map_slots() out of cluster lock. Link: http://lkml.kernel.org/r/20170317064635.12792-3-ying.huang@intel.comSigned-off-by:
Tim Chen <tim.c.chen@intel.com> Signed-off-by:
-
Huang Ying authored
This is just a cleanup patch, no functionality change. In cluster_list_add_tail(), spin_lock_nested() is used to lock the cluster, while unlock_cluster() is used to unlock the cluster. To improve the code readability, use spin_unlock() directly to unlock the cluster. Link: http://lkml.kernel.org/r/20170317064635.12792-2-ying.huang@intel.comSigned-off-by:
-
Huang Ying authored
Commit cbab0e4e ("swap: avoid read_swap_cache_async() race to deadlock while waiting on discard I/O completion") fixed a deadlock in read_swap_cache_async(). Because at that time, in swap allocation path, a swap entry may be set as SWAP_HAS_CACHE, then wait for discarding to complete before the page for the swap entry is added to the swap cache. But in commit 815c2c54 ("swap: make swap discard async"), the discarding for swap become asynchronous, waiting for discarding to complete will be done before the swap entry is set as SWAP_HAS_CACHE. So the comments in code is incorrect now. This patch fixes the comments. The cond_resched() added in the commit cbab0e4e is not necessary now too. But if we added some sleep in swap allocation path in the future, there may be some hard to debug/reproduce deadlock bug. So it is kept. Link: http://lkml.kernel.org/r/20170317064635.12792-1-ying.huang@intel.comSigned-off-by:
Rafael Aquini <aquini@redhat.com> Cc: Shaohua Li <shli@kernel.org> Signed-off-by:
-
Minchan Kim authored
There is no user for it. Remove it. [minchan@kernel.org: use false instead of SWAP_FAIL] Link: http://lkml.kernel.org/r/20170316053313.GA19241@bbox Link: http://lkml.kernel.org/r/1489555493-14659-11-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
rmap_one's return value controls whether rmap_work should contine to scan other ptes or not so it's target for changing to boolean. Return true if the scan should be continued. Otherwise, return false to stop the scanning. This patch makes rmap_one's return value to boolean. Link: http://lkml.kernel.org/r/1489555493-14659-10-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
There is no user of the return value from rmap_walk() and friends so this patch makes them void-returning functions. Link: http://lkml.kernel.org/r/1489555493-14659-9-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
try_to_unmap() returns SWAP_SUCCESS or SWAP_FAIL so it's suitable for boolean return. This patch changes it. Link: http://lkml.kernel.org/r/1489555493-14659-8-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
In 2002, [1] introduced SWAP_AGAIN. At that time, try_to_unmap_one used spin_trylock(&mm->page_table_lock) so it's really easy to contend and fail to hold a lock so SWAP_AGAIN to keep LRU status makes sense. However, now we changed it to mutex-based lock and be able to block without skip pte so there is few of small window to return SWAP_AGAIN so remove SWAP_AGAIN and just return SWAP_FAIL. [1] c48c43e, minimal rmap Link: http://lkml.kernel.org/r/1489555493-14659-7-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
ttu doesn't need to return SWAP_MLOCK. Instead, just return SWAP_FAIL because it means the page is not-swappable so it should move to another LRU list(active or unevictable). putback friends will move it to right list depending on the page's LRU flag. Link: http://lkml.kernel.org/r/1489555493-14659-6-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
try_to_munlock returns SWAP_MLOCK if the one of VMAs mapped the page has VM_LOCKED flag. In that time, VM set PG_mlocked to the page if the page is not pte-mapped THP which cannot be mlocked, either. With that, __munlock_isolated_page can use PageMlocked to check whether try_to_munlock is successful or not without relying on try_to_munlock's retval. It helps to make try_to_unmap/try_to_unmap_one simple with upcoming patches. [minchan@kernel.org: remove PG_Mlocked VM_BUG_ON check] Link: http://lkml.kernel.org/r/20170411025615.GA6545@bbox Link: http://lkml.kernel.org/r/1489555493-14659-5-git-send-email-minchan@kernel.orgSigned-off-by:
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by:
Vlastimil Babka <vbabka@suse.cz> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Sasha Levin <alexander.levin@verizon.com> Signed-off-by:
-
Minchan Kim authored
If the page is mapped and rescue in try_to_unmap_one, the page_mapcount() of a page cannot be zero, so the page_mapcount check in try_to_unmap is enough to return SWAP_SUCCESS. IOW, SWAP_MLOCK check is redundant so remove it. Link: http://lkml.kernel.org/r/1489555493-14659-4-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
If we found lazyfree page is dirty, try_to_unmap_one can just SetPageSwapBakced in there like PG_mlocked page and just return with SWAP_FAIL which is very natural because the page is not swappable right now so that vmscan can activate it. There is no point to introduce new return value SWAP_DIRTY in try_to_unmap at the moment. Link: http://lkml.kernel.org/r/1489555493-14659-3-git-send-email-minchan@kernel.orgSigned-off-by:
-
Minchan Kim authored
Nobody uses ret variable. Remove it. Link: http://lkml.kernel.org/r/1489555493-14659-2-git-send-email-minchan@kernel.orgSigned-off-by:
-
Yisheng Xie authored
By reviewing code, I find that when enter do_try_to_free_pages, the may_thrash is always clear, and it will retry shrink zones to tap cgroup's reserves memory by setting may_thrash when the former shrink_zones reclaim nothing. However, when memcg is disabled or on legacy hierarchy, or there do not have any memcg protected by low limit, it should not do this useless retry at all, for we do not have any cgroup's reserves memory to tap, and we have already done hard work but made no progress, which as Michal pointed out in former version, we are trying hard to control the retry logical of page alloctor, and the current additional round of reclaim is just lame. Therefore, to avoid this unneeded retrying and make code more readable, we remove the may_thrash field in scan_control, instead, introduce memcg_low_reclaim and memcg_low_skipped, and only retry when memcg_low_skipped, by setting memcg_low_reclaim. [xieyisheng1@huawei.com: remove may_thrash field, introduce mem_cgroup_reclaim] Link: http://lkml.kernel.org/r/1490191893-5923-1-git-send-email-ysxie@foxmail.com Link: http://lkml.kernel.org/r/1490191893-5923-1-git-send-email-ysxie@foxmail.comSigned-off-by:
Yisheng Xie <xieyisheng1@huawei.com> Acked-by:
Michal Hocko <mhocko@kernel.org> Suggested-by:
Shakeel Butt <shakeelb@google.com> Reviewed-by:
-
Yisheng Xie authored
By reviewing code, I find that if the migrate target is a large free page and we ignore suitable, it may splite large target free page into smaller block which is not good for defrag. So move the ignore block suitable after check large free page. As Vlastimil pointed out in RFC version that this patch is just based on logical analyses which might be better for future-proofing the function and it is most likely won't have any visible effect right now, for direct compaction shouldn't have to be called if there's a >=pageblock_order page already available. Link: http://lkml.kernel.org/r/1489490743-5364-1-git-send-email-xieyisheng1@huawei.comSigned-off-by:
-
