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* mm: fix pageblock bitmap allocationLinus Torvalds2013-02-181-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | Commit c060f943d092 ("mm: use aligned zone start for pfn_to_bitidx calculation") fixed out calculation of the index into the pageblock bitmap when a !SPARSEMEM zome was not aligned to pageblock_nr_pages. However, the _allocation_ of that bitmap had never taken this alignment requirement into accout, so depending on the exact size and alignment of the zone, the use of that index could then access past the allocation, resulting in some very subtle memory corruption. This was reported (and bisected) by Ingo Molnar: one of his random config builds would hang with certain very specific kernel command line options. In the meantime, commit c060f943d092 has been marked for stable, so this fix needs to be back-ported to the stable kernels that backported the commit to use the right alignment. Bisected-and-tested-by: Ingo Molnar <mingo@kernel.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: cma: fix accounting of CMA pages placed in high memoryMarek Szyprowski2013-02-121-0/+4
| | | | | | | | | | | | The total number of low memory pages is determined as totalram_pages - totalhigh_pages, so without this patch all CMA pageblocks placed in highmem were accounted to low memory. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Cc: Minchan Kim <minchan.kim@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: compaction: partially revert capture of suitable high-order pageMel Gorman2013-01-111-27/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Eric Wong reported on 3.7 and 3.8-rc2 that ppoll() got stuck when waiting for POLLIN on a local TCP socket. It was easier to trigger if there was disk IO and dirty pages at the same time and he bisected it to commit 1fb3f8ca0e92 ("mm: compaction: capture a suitable high-order page immediately when it is made available"). The intention of that patch was to improve high-order allocations under memory pressure after changes made to reclaim in 3.6 drastically hurt THP allocations but the approach was flawed. For Eric, the problem was that page->pfmemalloc was not being cleared for captured pages leading to a poor interaction with swap-over-NFS support causing the packets to be dropped. However, I identified a few more problems with the patch including the fact that it can increase contention on zone->lock in some cases which could result in async direct compaction being aborted early. In retrospect the capture patch took the wrong approach. What it should have done is mark the pageblock being migrated as MIGRATE_ISOLATE if it was allocating for THP and avoided races that way. While the patch was showing to improve allocation success rates at the time, the benefit is marginal given the relative complexity and it should be revisited from scratch in the context of the other reclaim-related changes that have taken place since the patch was first written and tested. This patch partially reverts commit 1fb3f8ca0e92 ("mm: compaction: capture a suitable high-order page immediately when it is made available"). Reported-and-tested-by: Eric Wong <normalperson@yhbt.net> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use aligned zone start for pfn_to_bitidx calculationLaura Abbott2013-01-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current calculation in pfn_to_bitidx assumes that (pfn - zone->zone_start_pfn) >> pageblock_order will return the same bit for all pfn in a pageblock. If zone_start_pfn is not aligned to pageblock_nr_pages, this may not always be correct. Consider the following with pageblock order = 10, zone start 2MB: pfn | pfn - zone start | (pfn - zone start) >> page block order ---------------------------------------------------------------- 0x26000 | 0x25e00 | 0x97 0x26100 | 0x25f00 | 0x97 0x26200 | 0x26000 | 0x98 0x26300 | 0x26100 | 0x98 This means that calling {get,set}_pageblock_migratetype on a single page will not set the migratetype for the full block. Fix this by rounding down zone_start_pfn when doing the bitidx calculation. For our use case, the effects of this bug were mostly tied to the fact that CMA allocations would either take a long time or fail to happen. Depending on the driver using CMA, this could result in anything from visual glitches to application failures. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fix zone_watermark_ok_safe() accounting of isolated pagesBartlomiej Zolnierkiewicz2013-01-051-27/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 702d1a6e0766 ("memory-hotplug: fix kswapd looping forever problem") added an isolated pageblocks counter (nr_pageblock_isolate in struct zone) and used it to adjust free pages counter in zone_watermark_ok_safe() to prevent kswapd looping forever problem. Then later, commit 2139cbe627b8 ("cma: fix counting of isolated pages") fixed accounting of isolated pages in global free pages counter. It made the previous zone_watermark_ok_safe() fix unnecessary and potentially harmful (cause now isolated pages may be accounted twice making free pages counter incorrect). This patch removes the special isolated pageblocks counter altogether which fixes zone_watermark_ok_safe() free pages check. Reported-by: Tomasz Stanislawski <t.stanislaws@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Cc: Minchan Kim <minchan@kernel.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Aaditya Kumar <aaditya.kumar.30@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michal Nazarewicz <mina86@mina86.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>
* mm: cma: WARN if freed memory is still in useMarek Szyprowski2012-12-211-2/+9
| | | | | | | | | | | | | Memory returned to free_contig_range() must have no other references. Let kernel to complain loudly if page reference count is not equal to 1. [rientjes@google.com: support sparsemem] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Michal Nazarewicz <mina86@mina86.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>
* mm: allocate kernel pages to the right memcgGlauber Costa2012-12-191-0/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a process tries to allocate a page with the __GFP_KMEMCG flag, the page allocator will call the corresponding memcg functions to validate the allocation. Tasks in the root memcg can always proceed. To avoid adding markers to the page - and a kmem flag that would necessarily follow, as much as doing page_cgroup lookups for no reason, whoever is marking its allocations with __GFP_KMEMCG flag is responsible for telling the page allocator that this is such an allocation at free_pages() time. This is done by the invocation of __free_accounted_pages() and free_accounted_pages(). Signed-off-by: Glauber Costa <glommer@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: JoonSoo Kim <js1304@gmail.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>
* mm/page_alloc.c: remove duplicate checkGavin Shan2012-12-191-2/+1
| | | | | | | | | | | | | | | | | While allocating pages using buddy allocator, the compound page is probably split up to free pages. Under these circumstances, the compound page should be destroyed by destroy_compound_page(). However, there is a duplicate check to judge if the page is compound. Remove the duplicate check since the compound_order() returns 0 when the page doesn't have PG_head set in destroy_compound_page(). That is to say, destroy_compound_page() needn't check PageHead(). Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'balancenuma-v11' of ↵Linus Torvalds2012-12-171-1/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma Pull Automatic NUMA Balancing bare-bones from Mel Gorman: "There are three implementations for NUMA balancing, this tree (balancenuma), numacore which has been developed in tip/master and autonuma which is in aa.git. In almost all respects balancenuma is the dumbest of the three because its main impact is on the VM side with no attempt to be smart about scheduling. In the interest of getting the ball rolling, it would be desirable to see this much merged for 3.8 with the view to building scheduler smarts on top and adapting the VM where required for 3.9. The most recent set of comparisons available from different people are mel: https://lkml.org/lkml/2012/12/9/108 mingo: https://lkml.org/lkml/2012/12/7/331 tglx: https://lkml.org/lkml/2012/12/10/437 srikar: https://lkml.org/lkml/2012/12/10/397 The results are a mixed bag. In my own tests, balancenuma does reasonably well. It's dumb as rocks and does not regress against mainline. On the other hand, Ingo's tests shows that balancenuma is incapable of converging for this workloads driven by perf which is bad but is potentially explained by the lack of scheduler smarts. Thomas' results show balancenuma improves on mainline but falls far short of numacore or autonuma. Srikar's results indicate we all suffer on a large machine with imbalanced node sizes. My own testing showed that recent numacore results have improved dramatically, particularly in the last week but not universally. We've butted heads heavily on system CPU usage and high levels of migration even when it shows that overall performance is better. There are also cases where it regresses. Of interest is that for specjbb in some configurations it will regress for lower numbers of warehouses and show gains for higher numbers which is not reported by the tool by default and sometimes missed in treports. Recently I reported for numacore that the JVM was crashing with NullPointerExceptions but currently it's unclear what the source of this problem is. Initially I thought it was in how numacore batch handles PTEs but I'm no longer think this is the case. It's possible numacore is just able to trigger it due to higher rates of migration. These reports were quite late in the cycle so I/we would like to start with this tree as it contains much of the code we can agree on and has not changed significantly over the last 2-3 weeks." * tag 'balancenuma-v11' of git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma: (50 commits) mm/rmap, migration: Make rmap_walk_anon() and try_to_unmap_anon() more scalable mm/rmap: Convert the struct anon_vma::mutex to an rwsem mm: migrate: Account a transhuge page properly when rate limiting mm: numa: Account for failed allocations and isolations as migration failures mm: numa: Add THP migration for the NUMA working set scanning fault case build fix mm: numa: Add THP migration for the NUMA working set scanning fault case. mm: sched: numa: Delay PTE scanning until a task is scheduled on a new node mm: sched: numa: Control enabling and disabling of NUMA balancing if !SCHED_DEBUG mm: sched: numa: Control enabling and disabling of NUMA balancing mm: sched: Adapt the scanning rate if a NUMA hinting fault does not migrate mm: numa: Use a two-stage filter to restrict pages being migrated for unlikely task<->node relationships mm: numa: migrate: Set last_nid on newly allocated page mm: numa: split_huge_page: Transfer last_nid on tail page mm: numa: Introduce last_nid to the page frame sched: numa: Slowly increase the scanning period as NUMA faults are handled mm: numa: Rate limit setting of pte_numa if node is saturated mm: numa: Rate limit the amount of memory that is migrated between nodes mm: numa: Structures for Migrate On Fault per NUMA migration rate limiting mm: numa: Migrate pages handled during a pmd_numa hinting fault mm: numa: Migrate on reference policy ...
| * mm: numa: Introduce last_nid to the page frameMel Gorman2012-12-111-0/+2
| | | | | | | | | | | | | | | | | | This patch introduces a last_nid field to the page struct. This is used to build a two-stage filter in the next patch that is aimed at mitigating a problem whereby pages migrate to the wrong node when referenced by a process that was running off its home node. Signed-off-by: Mel Gorman <mgorman@suse.de>
| * mm: numa: Structures for Migrate On Fault per NUMA migration rate limitingAndrea Arcangeli2012-12-111-0/+5
| | | | | | | | | | | | | | | | | | This defines the per-node data used by Migrate On Fault in order to rate limit the migration. The rate limiting is applied independently to each destination node. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Mel Gorman <mgorman@suse.de>
| * mm: migrate: Add a tracepoint for migrate_pagesMel Gorman2012-12-111-1/+2
| | | | | | | | | | | | | | | | | | | | The pgmigrate_success and pgmigrate_fail vmstat counters tells the user about migration activity but not the type or the reason. This patch adds a tracepoint to identify the type of page migration and why the page is being migrated. Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com>
* | Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds2012-12-131-35/+80
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc VM changes from Andrew Morton: "The rest of most-of-MM. The other MM bits await a slab merge. This patch includes the addition of a huge zero_page. Not a performance boost but it an save large amounts of physical memory in some situations. Also a bunch of Fujitsu engineers are working on memory hotplug. Which, as it turns out, was badly broken. About half of their patches are included here; the remainder are 3.8 material." However, this merge disables CONFIG_MOVABLE_NODE, which was totally broken. We don't add new features with "default y", nor do we add Kconfig questions that are incomprehensible to most people without any help text. Does the feature even make sense without compaction or memory hotplug? * akpm: (54 commits) mm/bootmem.c: remove unused wrapper function reserve_bootmem_generic() mm/memory.c: remove unused code from do_wp_page() asm-generic, mm: pgtable: consolidate zero page helpers mm/hugetlb.c: fix warning on freeing hwpoisoned hugepage hwpoison, hugetlbfs: fix RSS-counter warning hwpoison, hugetlbfs: fix "bad pmd" warning in unmapping hwpoisoned hugepage mm: protect against concurrent vma expansion memcg: do not check for mm in __mem_cgroup_count_vm_event tmpfs: support SEEK_DATA and SEEK_HOLE (reprise) mm: provide more accurate estimation of pages occupied by memmap fs/buffer.c: remove redundant initialization in alloc_page_buffers() fs/buffer.c: do not inline exported function writeback: fix a typo in comment mm: introduce new field "managed_pages" to struct zone mm, oom: remove statically defined arch functions of same name mm, oom: remove redundant sleep in pagefault oom handler mm, oom: cleanup pagefault oom handler memory_hotplug: allow online/offline memory to result movable node numa: add CONFIG_MOVABLE_NODE for movable-dedicated node mm, memcg: avoid unnecessary function call when memcg is disabled ...
| * | mm: provide more accurate estimation of pages occupied by memmapJiang Liu2012-12-131-2/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If SPARSEMEM is enabled, it won't build page structures for non-existing pages (holes) within a zone, so provide a more accurate estimation of pages occupied by memmap if there are bigger holes within the zone. And pages for highmem zones' memmap will be allocated from lowmem, so charge nr_kernel_pages for that. [akpm@linux-foundation.org: mark calc_memmap_size __paging_init] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Maciej Rutecki <maciej.rutecki@gmail.com> Cc: Chris Clayton <chris2553@googlemail.com> Cc: "Rafael J . Wysocki" <rjw@sisk.pl> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Tested-by: Jianguo Wu <wujianguo@huawei.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | mm: introduce new field "managed_pages" to struct zoneJiang Liu2012-12-131-14/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently a zone's present_pages is calcuated as below, which is inaccurate and may cause trouble to memory hotplug. spanned_pages - absent_pages - memmap_pages - dma_reserve. During fixing bugs caused by inaccurate zone->present_pages, we found zone->present_pages has been abused. The field zone->present_pages may have different meanings in different contexts: 1) pages existing in a zone. 2) pages managed by the buddy system. For more discussions about the issue, please refer to: http://lkml.org/lkml/2012/11/5/866 https://patchwork.kernel.org/patch/1346751/ This patchset tries to introduce a new field named "managed_pages" to struct zone, which counts "pages managed by the buddy system". And revert zone->present_pages to count "physical pages existing in a zone", which also keep in consistence with pgdat->node_present_pages. We will set an initial value for zone->managed_pages in function free_area_init_core() and will adjust it later if the initial value is inaccurate. For DMA/normal zones, the initial value is set to: (spanned_pages - absent_pages - memmap_pages - dma_reserve) Later zone->managed_pages will be adjusted to the accurate value when the bootmem allocator frees all free pages to the buddy system in function free_all_bootmem_node() and free_all_bootmem(). The bootmem allocator doesn't touch highmem pages, so highmem zones' managed_pages is set to the accurate value "spanned_pages - absent_pages" in function free_area_init_core() and won't be updated anymore. This patch also adds a new field "managed_pages" to /proc/zoneinfo and sysrq showmem. [akpm@linux-foundation.org: small comment tweaks] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Maciej Rutecki <maciej.rutecki@gmail.com> Tested-by: Chris Clayton <chris2553@googlemail.com> Cc: "Rafael J . Wysocki" <rjw@sisk.pl> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | numa: add CONFIG_MOVABLE_NODE for movable-dedicated nodeLai Jiangshan2012-12-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We need a node which only contains movable memory. This feature is very important for node hotplug. If a node has normal/highmem, the memory may be used by the kernel and can't be offlined. If the node only contains movable memory, we can offline the memory and the node. All are prepared, we can actually introduce N_MEMORY. add CONFIG_MOVABLE_NODE make we can use it for movable-dedicated node [akpm@linux-foundation.org: fix Kconfig text] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | page_alloc: use N_MEMORY instead N_HIGH_MEMORY change the node_states ↵Lai Jiangshan2012-12-131-18/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | initialization N_HIGH_MEMORY stands for the nodes that has normal or high memory. N_MEMORY stands for the nodes that has any memory. The code here need to handle with the nodes which have memory, we should use N_MEMORY instead. Since we introduced N_MEMORY, we update the initialization of node_states. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Christoph Lameter <cl@linux.com> Cc: Hillf Danton <dhillf@gmail.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>
| * | mm: use migrate_prep() instead of migrate_prep_local()Marek Szyprowski2012-12-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __alloc_contig_migrate_range() should use all possible ways to get all the pages migrated from the given memory range, so pruning per-cpu lru lists for all CPUs is required, regadless the cost of such operation. Otherwise some pages which got stuck at per-cpu lru list might get missed by migration procedure causing the contiguous allocation to fail. Reported-by: SeongHwan Yoon <sunghwan.yun@samsung.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge branch 'for-linus' of ↵Linus Torvalds2012-12-131-2/+2
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial branch from Jiri Kosina: "Usual stuff -- comment/printk typo fixes, documentation updates, dead code elimination." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) HOWTO: fix double words typo x86 mtrr: fix comment typo in mtrr_bp_init propagate name change to comments in kernel source doc: Update the name of profiling based on sysfs treewide: Fix typos in various drivers treewide: Fix typos in various Kconfig wireless: mwifiex: Fix typo in wireless/mwifiex driver messages: i2o: Fix typo in messages/i2o scripts/kernel-doc: check that non-void fcts describe their return value Kernel-doc: Convention: Use a "Return" section to describe return values radeon: Fix typo and copy/paste error in comments doc: Remove unnecessary declarations from Documentation/accounting/getdelays.c various: Fix spelling of "asynchronous" in comments. Fix misspellings of "whether" in comments. eisa: Fix spelling of "asynchronous". various: Fix spelling of "registered" in comments. doc: fix quite a few typos within Documentation target: iscsi: fix comment typos in target/iscsi drivers treewide: fix typo of "suport" in various comments and Kconfig treewide: fix typo of "suppport" in various comments ...
| * | propagate name change to comments in kernel sourceNadia Yvette Chambers2012-12-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | I've legally changed my name with New York State, the US Social Security Administration, et al. This patch propagates the name change and change in initials and login to comments in the kernel source as well. Signed-off-by: Nadia Yvette Chambers <nyc@holomorphy.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | mm: cma: remove watermark hacksMarek Szyprowski2012-12-121-58/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits 2139cbe627b8 ("cma: fix counting of isolated pages") and d95ea5d18e69 ("cma: fix watermark checking") introduced a reliable method of free page accounting when memory is being allocated from CMA regions, so the workaround introduced earlier by commit 49f223a9cd96 ("mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks") can be finally removed. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Mel Gorman <mel@csn.ul.ie> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | mm: cma: skip watermarks check for already isolated blocks in split_free_page()Marek Szyprowski2012-12-121-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 2139cbe627b8 ("cma: fix counting of isolated pages") free pages in isolated pageblocks are not accounted to NR_FREE_PAGES counters, so watermarks check is not required if one operates on a free page in isolated pageblock. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Mel Gorman <mel@csn.ul.ie> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | mm: introduce putback_movable_pages()Rafael Aquini2012-12-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PATCH "mm: introduce compaction and migration for virtio ballooned pages" hacks around putback_lru_pages() in order to allow ballooned pages to be re-inserted on balloon page list as if a ballooned page was like a LRU page. As ballooned pages are not legitimate LRU pages, this patch introduces putback_movable_pages() to properly cope with cases where the isolated pageset contains ballooned pages and LRU pages, thus fixing the mentioned inelegant hack around putback_lru_pages(). Signed-off-by: Rafael Aquini <aquini@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Andi Kleen <andi@firstfloor.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | memory-hotplug: allocate zone's pcp before onlining pagesWen Congyang2012-12-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We use __free_page() to put a page to buddy system when onlining pages. __free_page() will store NR_FREE_PAGES in zone's pcp.vm_stat_diff, so we should allocate zone's pcp before onlining pages, otherwise we will lose some free pages. [mhocko@suse.cz: make zone_pcp_reset independent of MEMORY_HOTREMOVE] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Christoph Lameter <cl@linux.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> 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>
* | | memory-hotplug: fix NR_FREE_PAGES mismatchWen Congyang2012-12-121-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NR_FREE_PAGES will be wrong after offlining pages. We add/dec NR_FREE_PAGES like this now: 1. move all pages in buddy system to MIGRATE_ISOLATE, and dec NR_FREE_PAGES 2. don't add NR_FREE_PAGES when it is freed and the migratetype is MIGRATE_ISOLATE 3. dec NR_FREE_PAGES when offlining isolated pages. 4. add NR_FREE_PAGES when undoing isolate pages. When we come to step 3, all pages are in MIGRATE_ISOLATE list, and NR_FREE_PAGES are right. When we come to step4, all pages are not in buddy system, so we don't change NR_FREE_PAGES in this step, but we change NR_FREE_PAGES in step3. So NR_FREE_PAGES is wrong after offlining pages. So there is no need to change NR_FREE_PAGES in step3. This patch also fixs a problem in step2: if the migratetype is MIGRATE_ISOLATE, we should not add NR_FRR_PAGES when we remove pages from pcppages. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Christoph Lameter <cl@linux.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Jianguo Wu <wujianguo106@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | memory-hotplug: skip HWPoisoned page when offlining pagesWen Congyang2012-12-121-4/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hwpoisoned may be set when we offline a page by the sysfs interface /sys/devices/system/memory/soft_offline_page or /sys/devices/system/memory/hard_offline_page. If we don't clear this flag when onlining pages, this page can't be freed, and will not in free list. So we can't offline these pages again. So we should skip such page when offlining pages. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Christoph Lameter <cl@linux.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Andi Kleen <andi@firstfloor.org> 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>
* | | mm: use IS_ENABLED(CONFIG_NUMA) instead of NUMA_BUILDKirill A. Shutemov2012-12-121-8/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't need custom NUMA_BUILD anymore, since we have handy IS_ENABLED(). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | mm: show migration types in show_memRabin Vincent2012-12-121-2/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is useful to diagnose the reason for page allocation failure for cases where there appear to be several free pages. Example, with this alloc_pages(GFP_ATOMIC) failure: swapper/0: page allocation failure: order:0, mode:0x0 ... Mem-info: Normal per-cpu: CPU 0: hi: 90, btch: 15 usd: 48 CPU 1: hi: 90, btch: 15 usd: 21 active_anon:0 inactive_anon:0 isolated_anon:0 active_file:0 inactive_file:84 isolated_file:0 unevictable:0 dirty:0 writeback:0 unstable:0 free:4026 slab_reclaimable:75 slab_unreclaimable:484 mapped:0 shmem:0 pagetables:0 bounce:0 Normal free:16104kB min:2296kB low:2868kB high:3444kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:336kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:331776kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:300kB slab_unreclaimable:1936kB kernel_stack:328kB pagetables:0kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no lowmem_reserve[]: 0 0 Before the patch, it's hard (for me, at least) to say why all these free chunks weren't considered for allocation: Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 1*256kB 1*512kB 1*1024kB 1*2048kB 3*4096kB = 16128kB After the patch, it's obvious that the reason is that all of these are in the MIGRATE_CMA (C) freelist: Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 1*256kB (C) 1*512kB (C) 1*1024kB (C) 1*2048kB (C) 3*4096kB (C) = 16128kB Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.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>
* | | Revert "revert "Revert "mm: remove __GFP_NO_KSWAPD""" and associated damageLinus Torvalds2012-12-101-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commits a50915394f1fc02c2861d3b7ce7014788aa5066e and d7c3b937bdf45f0b844400b7bf6fd3ed50bac604. This is a revert of a revert of a revert. In addition, it reverts the even older i915 change to stop using the __GFP_NO_KSWAPD flag due to the original commits in linux-next. It turns out that the original patch really was bogus, and that the original revert was the correct thing to do after all. We thought we had fixed the problem, and then reverted the revert, but the problem really is fundamental: waking up kswapd simply isn't the right thing to do, and direct reclaim sometimes simply _is_ the right thing to do. When certain allocations fail, we simply should try some direct reclaim, and if that fails, fail the allocation. That's the right thing to do for THP allocations, which can easily fail, and the GPU allocations want to do that too. So starting kswapd is sometimes simply wrong, and removing the flag that said "don't start kswapd" was a mistake. Let's hope we never revisit this mistake again - and certainly not this many times ;) Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Revert "mm: avoid waking kswapd for THP allocations when compaction is ↵Linus Torvalds2012-12-101-27/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | deferred or contended" This reverts commit 782fd30406ecb9d9b082816abe0c6008fc72a7b0. We are going to reinstate the __GFP_NO_KSWAPD flag that has been removed, the removal reverted, and then removed again. Making this commit a pointless fixup for a problem that was caused by the removal of __GFP_NO_KSWAPD flag. The thing is, we really don't want to wake up kswapd for THP allocations (because they fail quite commonly under any kind of memory pressure, including when there is tons of memory free), and these patches were just trying to fix up the underlying bug: the original removal of __GFP_NO_KSWAPD in commit c654345924f7 ("mm: remove __GFP_NO_KSWAPD") was simply bogus. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | mm: avoid waking kswapd for THP allocations when compaction is deferred or ↵Mel Gorman2012-11-301-10/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | contended With "mm: vmscan: scale number of pages reclaimed by reclaim/compaction based on failures" reverted, Zdenek Kabelac reported the following Hmm, so it's just took longer to hit the problem and observe kswapd0 spinning on my CPU again - it's not as endless like before - but still it easily eats minutes - it helps to turn off Firefox or TB (memory hungry apps) so kswapd0 stops soon - and restart those apps again. (And I still have like >1GB of cached memory) kswapd0 R running task 0 30 2 0x00000000 Call Trace: preempt_schedule+0x42/0x60 _raw_spin_unlock+0x55/0x60 put_super+0x31/0x40 drop_super+0x22/0x30 prune_super+0x149/0x1b0 shrink_slab+0xba/0x510 The sysrq+m indicates the system has no swap so it'll never reclaim anonymous pages as part of reclaim/compaction. That is one part of the problem but not the root cause as file-backed pages could also be reclaimed. The likely underlying problem is that kswapd is woken up or kept awake for each THP allocation request in the page allocator slow path. If compaction fails for the requesting process then compaction will be deferred for a time and direct reclaim is avoided. However, if there are a storm of THP requests that are simply rejected, it will still be the the case that kswapd is awake for a prolonged period of time as pgdat->kswapd_max_order is updated each time. This is noticed by the main kswapd() loop and it will not call kswapd_try_to_sleep(). Instead it will loopp, shrinking a small number of pages and calling shrink_slab() on each iteration. This patch defers when kswapd gets woken up for THP allocations. For !THP allocations, kswapd is always woken up. For THP allocations, kswapd is woken up iff the process is willing to enter into direct reclaim/compaction. [akpm@linux-foundation.org: fix typo in comment] Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Zdenek Kabelac <zkabelac@redhat.com> Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Cc: Jiri Slaby <jirislaby@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Glauber Costa <glommer@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | revert "Revert "mm: remove __GFP_NO_KSWAPD""Andrew Morton2012-11-301-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It apepars that this patch was innocent, and we hope that "mm: avoid waking kswapd for THP allocations when compaction is deferred or contended" will fix the final kswapd-spinning cause. Cc: Zdenek Kabelac <zkabelac@redhat.com> Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Jiri Slaby <jirislaby@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | mm: compaction: fix return value of capture_free_page()Mel Gorman2012-11-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ef6c5be658f6 ("fix incorrect NR_FREE_PAGES accounting (appears like memory leak)") fixes a NR_FREE_PAGE accounting leak but missed the return value which was also missed by this reviewer until today. That return value is used by compaction when adding pages to a list of isolated free pages and without this follow-up fix, there is a risk of free list corruption. Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Revert "mm: remove __GFP_NO_KSWAPD"Mel Gorman2012-11-271-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With "mm: vmscan: scale number of pages reclaimed by reclaim/compaction based on failures" reverted, Zdenek Kabelac reported the following Hmm, so it's just took longer to hit the problem and observe kswapd0 spinning on my CPU again - it's not as endless like before - but still it easily eats minutes - it helps to turn off Firefox or TB (memory hungry apps) so kswapd0 stops soon - and restart those apps again. (And I still have like >1GB of cached memory) kswapd0 R running task 0 30 2 0x00000000 Call Trace: preempt_schedule+0x42/0x60 _raw_spin_unlock+0x55/0x60 put_super+0x31/0x40 drop_super+0x22/0x30 prune_super+0x149/0x1b0 shrink_slab+0xba/0x510 The sysrq+m indicates the system has no swap so it'll never reclaim anonymous pages as part of reclaim/compaction. That is one part of the problem but not the root cause as file-backed pages could also be reclaimed. The likely underlying problem is that kswapd is woken up or kept awake for each THP allocation request in the page allocator slow path. If compaction fails for the requesting process then compaction will be deferred for a time and direct reclaim is avoided. However, if there are a storm of THP requests that are simply rejected, it will still be the the case that kswapd is awake for a prolonged period of time as pgdat->kswapd_max_order is updated each time. This is noticed by the main kswapd() loop and it will not call kswapd_try_to_sleep(). Instead it will loopp, shrinking a small number of pages and calling shrink_slab() on each iteration. The temptation is to supply a patch that checks if kswapd was woken for THP and if so ignore pgdat->kswapd_max_order but it'll be a hack and not backed up by proper testing. As 3.7 is very close to release and this is not a bug we should release with, a safer path is to revert "mm: remove __GFP_NO_KSWAPD" for now and revisit it with the view to ironing out the balance_pgdat() logic in general. Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Zdenek Kabelac <zkabelac@redhat.com> Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Jiri Slaby <jirislaby@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | fix incorrect NR_FREE_PAGES accounting (appears like memory leak)Dave Hansen2012-11-211-1/+1
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There have been some 3.7-rc reports of vm issues, including some kswapd bugs and, more importantly, some memory "leaks": http://www.spinics.net/lists/linux-mm/msg46187.html https://bugzilla.kernel.org/show_bug.cgi?id=50181 Commit 1fb3f8ca0e92 ("mm: compaction: capture a suitable high-order page immediately when it is made available") took split_free_page() and reused it for the compaction code. It does something curious with capture_free_page() (previously known as split_free_page()): int capture_free_page(struct page *page, int alloc_order, ... __mod_zone_page_state(zone, NR_FREE_PAGES, -(1UL << order)); - /* Split into individual pages */ - set_page_refcounted(page); - split_page(page, order); + if (alloc_order != order) + expand(zone, page, alloc_order, order, + &zone->free_area[order], migratetype); Note that expand() puts the pages _back_ in the allocator, but it does not bump NR_FREE_PAGES. We "return" 'alloc_order' worth of pages, but we accounted for removing 'order' in the __mod_zone_page_state() call. For the old split_page()-style use (order==alloc_order) the bug will not trigger. But, when called from the compaction code where we occasionally get a larger page out of the buddy allocator than we need, we will run in to this. This patch simply changes the NR_FREE_PAGES manipulation to the correct 'alloc_order' instead of 'order'. I've been able to repeatedly trigger this in my testing environment. The amount "leaked" very closely tracks the imbalance I see in buddy pages vs. NR_FREE_PAGES. I have confirmed that this patch fixes the imbalance Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | revert "mm: fix-up zone present pages"Andrew Morton2012-11-161-34/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert commit 7f1290f2f2a4 ("mm: fix-up zone present pages") That patch tried to fix a issue when calculating zone->present_pages, but it caused a regression on 32bit systems with HIGHMEM. With that change, reset_zone_present_pages() resets all zone->present_pages to zero, and fixup_zone_present_pages() is called to recalculate zone->present_pages when the boot allocator frees core memory pages into buddy allocator. Because highmem pages are not freed by bootmem allocator, all highmem zones' present_pages becomes zero. Various options for improving the situation are being discussed but for now, let's return to the 3.6 code. Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Petr Tesarik <ptesarik@suse.cz> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David Rientjes <rientjes@google.com> Tested-by: Chris Clayton <chris2553@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | memcg: fix hotplugged memory zone oopsHugh Dickins2012-11-161-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When MEMCG is configured on (even when it's disabled by boot option), when adding or removing a page to/from its lru list, the zone pointer used for stats updates is nowadays taken from the struct lruvec. (On many configurations, calculating zone from page is slower.) But we have no code to update all the lruvecs (per zone, per memcg) when a memory node is hotadded. Here's an extract from the oops which results when running numactl to bind a program to a newly onlined node: BUG: unable to handle kernel NULL pointer dereference at 0000000000000f60 IP: __mod_zone_page_state+0x9/0x60 Pid: 1219, comm: numactl Not tainted 3.6.0-rc5+ #180 Bochs Bochs Process numactl (pid: 1219, threadinfo ffff880039abc000, task ffff8800383c4ce0) Call Trace: __pagevec_lru_add_fn+0xdf/0x140 pagevec_lru_move_fn+0xb1/0x100 __pagevec_lru_add+0x1c/0x30 lru_add_drain_cpu+0xa3/0x130 lru_add_drain+0x2f/0x40 ... The natural solution might be to use a memcg callback whenever memory is hotadded; but that solution has not been scoped out, and it happens that we do have an easy location at which to update lruvec->zone. The lruvec pointer is discovered either by mem_cgroup_zone_lruvec() or by mem_cgroup_page_lruvec(), and both of those do know the right zone. So check and set lruvec->zone in those; and remove the inadequate attempt to set lruvec->zone from lruvec_init(), which is called before NODE_DATA(node) has been allocated in such cases. Ah, there was one exceptionr. For no particularly good reason, mem_cgroup_force_empty_list() has its own code for deciding lruvec. Change it to use the standard mem_cgroup_zone_lruvec() and mem_cgroup_get_lru_size() too. In fact it was already safe against such an oops (the lru lists in danger could only be empty), but we're better proofed against future changes this way. I've marked this for stable (3.6) since we introduced the problem in 3.5 (now closed to stable); but I have no idea if this is the only fix needed to get memory hotadd working with memcg in 3.6, and received no answer when I enquired twice before. Reported-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, numa: avoid setting zone_reclaim_mode unless a node is sufficiently distantDavid Rientjes2012-10-251-2/+2
| | | | | | | | | | | | | | | | Commit 957f822a0ab9 ("mm, numa: reclaim from all nodes within reclaim distance") caused zone_reclaim_mode to be set for all systems where two nodes are within RECLAIM_DISTANCE of each other. This is the opposite of what we actually want: zone_reclaim_mode should be set if two nodes are sufficiently distant. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Julian Wollrath <jwollrath@web.de> Tested-by: Julian Wollrath <jwollrath@web.de> Cc: Hugh Dickins <hughd@google.com> Cc: Patrik Kullman <patrik.kullman@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c:alloc_contig_range(): return early for err pathBob Liu2012-10-251-1/+1
| | | | | | | | | | | If start_isolate_page_range() failed, unset_migratetype_isolate() has been done inside it. Signed-off-by: Bob Liu <lliubbo@gmail.com> Cc: Ni zhan Chen <nizhan.chen@gmail.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cma: decrease cc.nr_migratepages after reclaiming pagelistMinchan Kim2012-10-091-2/+4
| | | | | | | | | | | | | | reclaim_clean_pages_from_list() reclaims clean pages before migration so cc.nr_migratepages should be updated. Currently, there is no problem but it can be wrong if we try to use the value in future. Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* CMA: migrate mlocked pagesMinchan Kim2012-10-091-1/+1
| | | | | | | | | | | | | | | | | | | | Presently CMA cannot migrate mlocked pages so it ends up failing to allocate contiguous memory space. This patch makes mlocked pages be migrated out. Of course, it can affect realtime processes but in CMA usecase, contiguous memory allocation failing is far worse than access latency to an mlocked page being variable while CMA is running. If someone wants to make the system realtime, he shouldn't enable CMA because stalls can still happen at random times. [akpm@linux-foundation.org: tweak comment text, per Mel] Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* memory-hotplug: fix zone stat mismatchMinchan Kim2012-10-091-0/+7
| | | | | | | | | | | | | | | | | | | | | | During memory-hotplug, I found NR_ISOLATED_[ANON|FILE] are increasing, causing the kernel to hang. When the system doesn't have enough free pages, it enters reclaim but never reclaim any pages due to too_many_isolated()==true and loops forever. The cause is that when we do memory-hotadd after memory-remove, __zone_pcp_update() clears a zone's ZONE_STAT_ITEMS in setup_pageset() although the vm_stat_diff of all CPUs still have values. In addtion, when we offline all pages of the zone, we reset them in zone_pcp_reset without draining so we loss some zone stat item. Reviewed-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, numa: reclaim from all nodes within reclaim distanceDavid Rientjes2012-10-091-11/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | RECLAIM_DISTANCE represents the distance between nodes at which it is deemed too costly to allocate from; it's preferred to try to reclaim from a local zone before falling back to allocating on a remote node with such a distance. To do this, zone_reclaim_mode is set if the distance between any two nodes on the system is greather than this distance. This, however, ends up causing the page allocator to reclaim from every zone regardless of its affinity. What we really want is to reclaim only from zones that are closer than RECLAIM_DISTANCE. This patch adds a nodemask to each node that represents the set of nodes that are within this distance. During the zone iteration, if the bit for a zone's node is set for the local node, then reclaim is attempted; otherwise, the zone is skipped. [akpm@linux-foundation.org: fix CONFIG_NUMA=n build] Signed-off-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: remove free_page_mlockHugh Dickins2012-10-091-17/+0
| | | | | | | | | | | | | | | | | We should not be seeing non-0 unevictable_pgs_mlockfreed any longer. So remove free_page_mlock() from the page freeing paths: __PG_MLOCKED is already in PAGE_FLAGS_CHECK_AT_FREE, so free_pages_check() will now be checking it, reporting "BUG: Bad page state" if it's ever found set. Comment UNEVICTABLE_MLOCKFREED and unevictable_pgs_mlockfreed always 0. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michel Lespinasse <walken@google.com> Cc: Ying Han <yinghan@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fix-up zone present pagesJianguo Wu2012-10-091-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I think zone->present_pages indicates pages that buddy system can management, it should be: zone->present_pages = spanned pages - absent pages - bootmem pages, but is now: zone->present_pages = spanned pages - absent pages - memmap pages. spanned pages: total size, including holes. absent pages: holes. bootmem pages: pages used in system boot, managed by bootmem allocator. memmap pages: pages used by page structs. This may cause zone->present_pages less than it should be. For example, numa node 1 has ZONE_NORMAL and ZONE_MOVABLE, it's memmap and other bootmem will be allocated from ZONE_MOVABLE, so ZONE_NORMAL's present_pages should be spanned pages - absent pages, but now it also minus memmap pages(free_area_init_core), which are actually allocated from ZONE_MOVABLE. When offlining all memory of a zone, this will cause zone->present_pages less than 0, because present_pages is unsigned long type, it is actually a very large integer, it indirectly caused zone->watermark[WMARK_MIN] becomes a large integer(setup_per_zone_wmarks()), than cause totalreserve_pages become a large integer(calculate_totalreserve_pages()), and finally cause memory allocating failure when fork process(__vm_enough_memory()). [root@localhost ~]# dmesg -bash: fork: Cannot allocate memory I think the bug described in http://marc.info/?l=linux-mm&m=134502182714186&w=2 is also caused by wrong zone present pages. This patch intends to fix-up zone->present_pages when memory are freed to buddy system on x86_64 and IA64 platforms. Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Reported-by: Petr Tesarik <ptesarik@suse.cz> Tested-by: Petr Tesarik <ptesarik@suse.cz> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc: refactor out __alloc_contig_migrate_alloc()Minchan Kim2012-10-091-13/+1
| | | | | | | | | | | | | | | | __alloc_contig_migrate_alloc() can be used by memory-hotplug so refactor it out (move + rename as a common name) into page_isolation.c. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: compaction: clear PG_migrate_skip based on compaction and reclaim activityMel Gorman2012-10-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compaction caches if a pageblock was scanned and no pages were isolated so that the pageblocks can be skipped in the future to reduce scanning. This information is not cleared by the page allocator based on activity due to the impact it would have to the page allocator fast paths. Hence there is a requirement that something clear the cache or pageblocks will be skipped forever. Currently the cache is cleared if there were a number of recent allocation failures and it has not been cleared within the last 5 seconds. Time-based decisions like this are terrible as they have no relationship to VM activity and is basically a big hammer. Unfortunately, accurate heuristics would add cost to some hot paths so this patch implements a rough heuristic. There are two cases where the cache is cleared. 1. If a !kswapd process completes a compaction cycle (migrate and free scanner meet), the zone is marked compact_blockskip_flush. When kswapd goes to sleep, it will clear the cache. This is expected to be the common case where the cache is cleared. It does not really matter if kswapd happens to be asleep or going to sleep when the flag is set as it will be woken on the next allocation request. 2. If there have been multiple failures recently and compaction just finished being deferred then a process will clear the cache and start a full scan. This situation happens if there are multiple high-order allocation requests under heavy memory pressure. The clearing of the PG_migrate_skip bits and other scans is inherently racy but the race is harmless. For allocations that can fail such as THP, they will simply fail. For requests that cannot fail, they will retry the allocation. Tests indicated that scanning rates were roughly similar to when the time-based heuristic was used and the allocation success rates were similar. Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Richard Davies <richard@arachsys.com> Cc: Shaohua Li <shli@kernel.org> Cc: Avi Kivity <avi@redhat.com> Cc: Rafael Aquini <aquini@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: compaction: cache if a pageblock was scanned and no pages were isolatedMel Gorman2012-10-091-18/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When compaction was implemented it was known that scanning could potentially be excessive. The ideal was that a counter be maintained for each pageblock but maintaining this information would incur a severe penalty due to a shared writable cache line. It has reached the point where the scanning costs are a serious problem, particularly on long-lived systems where a large process starts and allocates a large number of THPs at the same time. Instead of using a shared counter, this patch adds another bit to the pageblock flags called PG_migrate_skip. If a pageblock is scanned by either migrate or free scanner and 0 pages were isolated, the pageblock is marked to be skipped in the future. When scanning, this bit is checked before any scanning takes place and the block skipped if set. The main difficulty with a patch like this is "when to ignore the cached information?" If it's ignored too often, the scanning rates will still be excessive. If the information is too stale then allocations will fail that might have otherwise succeeded. In this patch o CMA always ignores the information o If the migrate and free scanner meet then the cached information will be discarded if it's at least 5 seconds since the last time the cache was discarded o If there are a large number of allocation failures, discard the cache. The time-based heuristic is very clumsy but there are few choices for a better event. Depending solely on multiple allocation failures still allows excessive scanning when THP allocations are failing in quick succession due to memory pressure. Waiting until memory pressure is relieved would cause compaction to continually fail instead of using reclaim/compaction to try allocate the page. The time-based mechanism is clumsy but a better option is not obvious. Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: Richard Davies <richard@arachsys.com> Cc: Shaohua Li <shli@kernel.org> Cc: Avi Kivity <avi@redhat.com> Acked-by: Rafael Aquini <aquini@redhat.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* revert "mm: have order > 0 compaction start off where it left"Mel Gorman2012-10-091-5/+0
| | | | | | | | | | | | | | | | | | | | | This reverts commit 7db8889ab05b ("mm: have order > 0 compaction start off where it left") and commit de74f1cc ("mm: have order > 0 compaction start near a pageblock with free pages"). These patches were a good idea and tests confirmed that they massively reduced the amount of scanning but the implementation is complex and tricky to understand. A later patch will cache what pageblocks should be skipped and reimplements the concept of compact_cached_free_pfn on top for both migration and free scanners. Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: Richard Davies <richard@arachsys.com> Cc: Shaohua Li <shli@kernel.org> Cc: Avi Kivity <avi@redhat.com> Acked-by: Rafael Aquini <aquini@redhat.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>
* mm/memblock: cleanup early_node_map[] related commentsWanpeng Li2012-10-091-1/+1
| | | | | | | | | | | | | | Commit 0ee332c14518 ("memblock: Kill early_node_map[]") removed early_node_map[]. Clean up the comments to comply with that change. Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Gavin Shan <shangw@linux.vnet.ibm.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>