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2009-10-29vmscan: order evictable rescue in LRU putbackJohannes Weiner
Isolators putting a page back to the LRU do not hold the page lock, and if the page is mlocked, another thread might munlock it concurrently. Expecting this, the putback code re-checks the evictability of a page when it just moved it to the unevictable list in order to correct its decision. The problem, however, is that ordering is not garuanteed between setting PG_lru when moving the page to the list and checking PG_mlocked afterwards: #0: #1 spin_lock() if (TestClearPageMlocked()) if (PageLRU()) move to evictable list SetPageLRU() spin_unlock() if (!PageMlocked()) move to evictable list The PageMlocked() check may get reordered before SetPageLRU() in #0, resulting in #0 not moving the still mlocked page, and in #1 failing to isolate and move the page as well. The page is now stranded on the unevictable list. The race condition is very unlikely. The consequence currently is one page falling off the reclaim grid and eventually getting freed with PG_unevictable set, which triggers a warning in the page allocator. TestClearPageMlocked() in #1 already provides full memory barrier semantics. This patch adds an explicit full barrier to force ordering between SetPageLRU() and PageMlocked() so that either one of the competitors rescues the page. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-29do_mbind(): fix memory leakKOSAKI Motohiro
If migrate_prep is failed, new variable is leaked. This patch fixes it. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Christoph Lameter <cl@linux-foundation.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-29mbind(): fix leak of never putback pagesKOSAKI Motohiro
If mbind() receives an invalid address, do_mbind leaks a page. The following test program detects this leak. This patch fixes it. migrate_efault.c ======================================= #include <numaif.h> #include <numa.h> #include <sys/mman.h> #include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <string.h> static unsigned long pagesize; static void* make_hole_mapping(void) { void* addr; addr = mmap(NULL, pagesize*3, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, 0, 0); if (addr == MAP_FAILED) return NULL; /* make page populate */ memset(addr, 0, pagesize*3); /* make memory hole */ munmap(addr+pagesize, pagesize); return addr; } int main(int argc, char** argv) { void* addr; int ch; int node; struct bitmask *nmask = numa_allocate_nodemask(); int err; int node_set = 0; while ((ch = getopt(argc, argv, "n:")) != -1){ switch (ch){ case 'n': node = strtol(optarg, NULL, 0); numa_bitmask_setbit(nmask, node); node_set = 1; break; default: ; } } argc -= optind; argv += optind; if (!node_set) numa_bitmask_setbit(nmask, 0); pagesize = getpagesize(); addr = make_hole_mapping(); err = mbind(addr, pagesize*3, MPOL_BIND, nmask->maskp, nmask->size, MPOL_MF_MOVE_ALL); if (err) perror("mbind "); return 0; } ======================================= Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Christoph Lameter <cl@linux-foundation.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-29vmscan: limit VM_EXEC protection to file pagesWu Fengguang
It is possible to have !Anon but SwapBacked pages, and some apps could create huge number of such pages with MAP_SHARED|MAP_ANONYMOUS. These pages go into the ANON lru list, and hence shall not be protected: we only care mapped executable files. Failing to do so may trigger OOM. Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-29revert "mm: oom analysis: add buffer cache information to show_free_areas()"Andrew Morton
Revert commit 71de1ccbe1fb40203edd3beb473f8580d917d2ca Author: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> AuthorDate: Mon Sep 21 17:01:31 2009 -0700 Commit: Linus Torvalds <torvalds@linux-foundation.org> CommitDate: Tue Sep 22 07:17:27 2009 -0700 mm: oom analysis: add buffer cache information to show_free_areas() show_free_areas() is called during page allocation failures, and page allocation failures can occur in any calling context. But nr_blockdev_pages() takes VFS locks which should not be taken from hard IRQ context (at least). The result is lockdep warnings (and deadlockability) during page allocation failures. Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-29congestion_wait(): don't use WRITEKOSAKI Motohiro
commit 8aa7e847d (Fix congestion_wait() sync/async vs read/write confusion) replace WRITE with BLK_RW_ASYNC. Unfortunately, concurrent mm development made the unchanged place accidentally. This patch fixes it too. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-29hwpoison: fix oops on ksm pagesHugh Dickins
Memory failure on a KSM page currently oopses on its NULL anon_vma in page_lock_anon_vma(): that may not be much worse than the consequence of ignoring it, but it is better to be consistent with how ZERO_PAGE and hugetlb pages and other awkward cases are treated. Just skip it. We could fix it for 2.6.32 at the KSM end, by putting a dummy anon_vma pointer in there; but that would get harder next time, when KSM will put a pointer to something else there (and I'm not currently planning to do any work to open that up to memory_failure). So I would prefer this simple PageKsm test, until the other exceptions are handled. Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-13Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: cciss: Add cciss_allow_hpsa module parameter cciss: Fix multiple calls to pci_release_regions blk-settings: fix function parameter kernel-doc notation writeback: kill space in debugfs item name writeback: account IO throttling wait as iowait elv_iosched_store(): fix strstrip() misuse cfq-iosched: avoid probable slice overrun when idling cfq-iosched: apply bool value where we return 0/1 cfq-iosched: fix think time allowed for seekers cfq-iosched: fix the slice residual sign cfq-iosched: abstract out the 'may this cfqq dispatch' logic block: use proper BLK_RW_ASYNC in blk_queue_start_tag() block: Seperate read and write statistics of in_flight requests v2 block: get rid of kblock_schedule_delayed_work() cfq-iosched: fix possible problem with jiffies wraparound cfq-iosched: fix issue with rq-rq merging and fifo list ordering
2009-10-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: percpu: fix compile warnings
2009-10-12percpu: fix compile warningsTejun Heo
Fix the following two compile warnings which show up on i386. mm/percpu.c:1873: warning: comparison of distinct pointer types lacks a cast mm/percpu.c:1879: warning: format '%lx' expects type 'long unsigned int', but argument 2 has type 'size_t' Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
2009-10-11headers: remove sched.h from interrupt.hAlexey Dobriyan
After m68k's task_thread_info() doesn't refer to current, it's possible to remove sched.h from interrupt.h and not break m68k! Many thanks to Heiko Carstens for allowing this. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-10-09kmemleak: Check for NULL pointer returned by create_object()Catalin Marinas
This patch adds NULL pointer checking in the early_alloc() function. Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-09kmemleak: Use GFP_ATOMIC for early_alloc().Tetsuo Handa
We can't use GFP_KERNEL inside rcu_read_lock(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-09writeback: kill space in debugfs item nameWu Fengguang
The space is not script friendly, kill it. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-09writeback: account IO throttling wait as iowaitWu Fengguang
It makes sense to do IOWAIT when someone is blocked due to IO throttle, as suggested by Kame and Peter. There is an old comment for not doing IOWAIT on throttle, however it has been mismatching the code for a long time. If we stop accounting IOWAIT for 2.6.32, it could be an undesirable behavior change. So restore the io_schedule. CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> CC: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-08Merge branch 'sparc-perf-events-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sparc-perf-events-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: mm, perf_event: Make vmalloc_user() align base kernel virtual address to SHMLBA perf_event: Provide vmalloc() based mmap() backing
2009-10-08mm, perf_event: Make vmalloc_user() align base kernel virtual address to SHMLBADavid Miller
When a vmalloc'd area is mmap'd into userspace, some kind of co-ordination is necessary for this to work on platforms with cpu D-caches which can have aliases. Otherwise kernel side writes won't be seen properly in userspace and vice versa. If the kernel side mapping and the user side one have the same alignment, modulo SHMLBA, this can work as long as VM_SHARED is shared of VMA and for all current users this is true. VM_SHARED will force SHMLBA alignment of the user side mmap on platforms with D-cache aliasing matters. The bulk of this patch is just making it so that a specific alignment can be passed down into __get_vm_area_node(). All existing callers pass in '1' which preserves existing behavior. vmalloc_user() gives SHMLBA for the alignment. As a side effect this should get the video media drivers and other vmalloc_user() users into more working shape on such systems. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <200909211922.n8LJMYjw029425@imap1.linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-08mm: includecheck fix: vmalloc.cJaswinder Singh Rajput
fix the following 'make includecheck' warning: mm/vmalloc.c: linux/highmem.h is included more than once. Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08ksm: more on default valuesHugh Dickins
Adjust the max_kernel_pages default to a quarter of totalram_pages, instead of nr_free_buffer_pages() / 4: the KSM pages themselves come from highmem, and even on a 16GB PAE machine, 4GB of KSM pages would only be pinning 32MB of lowmem with their rmap_items, so no need for the more obscure calculation (nor for its own special init function). There is no way for the user to switch KSM on if CONFIG_SYSFS is not enabled, so in that case default run to KSM_RUN_MERGE. Update KSM Documentation and Kconfig to reflect the new defaults. Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Izik Eidus <ieidus@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-04Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (41 commits) Revert "Seperate read and write statistics of in_flight requests" cfq-iosched: don't delay async queue if it hasn't dispatched at all block: Topology ioctls cfq-iosched: use assigned slice sync value, not default cfq-iosched: rename 'desktop' sysfs entry to 'low_latency' cfq-iosched: implement slower async initiate and queue ramp up cfq-iosched: delay async IO dispatch, if sync IO was just done cfq-iosched: add a knob for desktop interactiveness Add a tracepoint for block request remapping block: allow large discard requests block: use normal I/O path for discard requests swapfile: avoid NULL pointer dereference in swapon when s_bdev is NULL fs/bio.c: move EXPORT* macros to line after function Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs cciss: fix build when !PROC_FS block: Do not clamp max_hw_sectors for stacking devices block: Set max_sectors correctly for stacking devices cciss: cciss_host_attr_groups should be const cciss: Dynamically allocate the drive_info_struct for each logical drive. cciss: Add usage_count attribute to each logical drive in /sys ...
2009-10-01memcg: reduce check for softlimit excessKAMEZAWA Hiroyuki
In charge/uncharge/reclaim path, usage_in_excess is calculated repeatedly and it takes res_counter's spin_lock every time. This patch removes unnecessary calls for res_count_soft_limit_excess. Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01memcg: some modification to softlimit under hierarchical memory reclaim.KAMEZAWA Hiroyuki
This patch clean up/fixes for memcg's uncharge soft limit path. Problems: Now, res_counter_charge()/uncharge() handles softlimit information at charge/uncharge and softlimit-check is done when event counter per memcg goes over limit. Now, event counter per memcg is updated only when memory usage is over soft limit. Here, considering hierarchical memcg management, ancesotors should be taken care of. Now, ancerstors(hierarchy) are handled in charge() but not in uncharge(). This is not good. Prolems: 1. memcg's event counter incremented only when softlimit hits. That's bad. It makes event counter hard to be reused for other purpose. 2. At uncharge, only the lowest level rescounter is handled. This is bug. Because ancesotor's event counter is not incremented, children should take care of them. 3. res_counter_uncharge()'s 3rd argument is NULL in most case. ops under res_counter->lock should be small. No "if" sentense is better. Fixes: * Removed soft_limit_xx poitner and checks in charge and uncharge. Do-check-only-when-necessary scheme works enough well without them. * make event-counter of memcg incremented at every charge/uncharge. (per-cpu area will be accessed soon anyway) * All ancestors are checked at soft-limit-check. This is necessary because ancesotor's event counter may never be modified. Then, they should be checked at the same time. Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01memcg: fix refcnt going negativeKAMEZAWA Hiroyuki
__mem_cgroup_largest_soft_limit_node() returns a mem_cgroup_per_zone "mz" with incremnted mz->mem->css's refcnt. Then, the caller of this function has to call css_put(mz->mem->css). But, mz can be !NULL even if "not found" i.e. without css_get(). By this, css->refcnt will go down to minus. This may cause various things...one of results will be initite-loop in css_tryget() as this. INFO: RCU detected CPU 0 stall (t=10000 jiffies) sending NMI to all CPUs: NMI backtrace for cpu 0 CPU 0: <snip> <<EOE>> <IRQ> [<ffffffff810884bd>] trace_hardirqs_off+0xd/0x10 [<ffffffff8102a940>] flat_send_IPI_mask+0x90/0xb0 [<ffffffff8102a9c9>] flat_send_IPI_all+0x69/0x70 [<ffffffff81027372>] arch_trigger_all_cpu_backtrace+0x62/0xa0 [<ffffffff810bff8e>] __rcu_pending+0x7e/0x370 [<ffffffff810c02c7>] rcu_check_callbacks+0x47/0x130 [<ffffffff81063a26>] update_process_times+0x46/0x70 [<ffffffff81085930>] tick_sched_timer+0x60/0x160 [<ffffffff810858d0>] ? tick_sched_timer+0x0/0x160 [<ffffffff8107a03a>] __run_hrtimer+0xba/0x150 [<ffffffff8107a325>] hrtimer_interrupt+0xd5/0x1b0 [<ffffffff81426dfe>] ? trace_hardirqs_off_thunk+0x3a/0x3c [<ffffffff8142cacd>] smp_apic_timer_interrupt+0x6d/0x9b [<ffffffff8100cb33>] apic_timer_interrupt+0x13/0x20 <EOI> [<ffffffff811317b6>] ? mem_cgroup_walk_tree+0x156/0x180 [<ffffffff811316d3>] ? mem_cgroup_walk_tree+0x73/0x180 [<ffffffff81131692>] ? mem_cgroup_walk_tree+0x32/0x180 [<ffffffff81131a00>] ? mem_cgroup_get_local_stat+0x0/0x110 [<ffffffff81131d5b>] ? mem_control_stat_show+0x14b/0x330 [<ffffffff810a57fd>] ? cgroup_seqfile_show+0x3d/0x60 Above shows CPU0 caught in css_tryget()'s inifinite loop because of bad refcnt. This is a fix to set mz=NULL at the top of retry path. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Paul Menage <menage@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01mm/rmap.c: fix commentHuang Shijie
The page_address_in_vma() is not only used in unuse_vma(). Signed-off-by: Huang Shijie <shijie8@gmail.com> Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01swapfile: avoid NULL pointer dereference in swapon when s_bdev is NULLSuresh Jayaraman
While testing Swap over NFS patchset, I noticed an oops that was triggered during swapon. Investigating further, the NULL pointer deference is due to the SSD device check/optimization in the swapon code that assumes s_bdev could never be NULL. inode->i_sb->s_bdev could be NULL in a few cases. For e.g. one such case is loopback NFS mount, there could be others as well. Fix this by ensuring s_bdev is not NULL before we try to deference s_bdev. Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-29percpu: make allocation failures more verboseTejun Heo
Warn and dump stack when percpu allocation fails. percpu allocator is still young and unchecked NULL percpu pointer usage can result in random memory corruption when combined with the pointer shifting in access macros. Allocation failures should be rare and the warning message will be disabled after certain times. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-09-29percpu: make pcpu_setup_first_chunk() failures more verboseTejun Heo
The parameters to pcpu_setup_first_chunk() come from different sources depending on architecture and can be quite complex. The function runs various sanity checks on the parameters and triggers BUG() if something isn't right. However, this is very early during the boot and not reporting exactly what the problem is makes debugging even harder. Add PCPU_SETUP_BUG() macro which prints out enough information about the parameters. As the macro still puts separate BUG() for each check, it won't lose any information even on the situations where only the program counter can be retrieved. While at it, also bump pcpu_dump_alloc_info() message to KERN_INFO so that it's visible on the console if boot fails to complete. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-09-29percpu: make embedding first chunk allocator check vmalloc space sizeTejun Heo
Embedding first chunk allocator maintains the distances between units in the vmalloc area and thus needs vmalloc space to be larger than the maximum distances between units; otherwise, it wouldn't be able to create any dynamic chunks. This patch makes the embedding first chunk allocator check vmalloc space size and if the maximum distance between units is larger than 75% of it, print warning and, if page mapping allocator is available, fail initialization so that the system falls back onto it. This should work around percpu allocation failure problems on certain sparc64 configurations where distances between NUMA nodes are larger than the vmalloc area and makes percpu allocator more robust for future configurations. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-09-29percpu: make pcpu_build_alloc_info() clear static buffersTejun Heo
pcpu_build_alloc_info() may be called multiple times when percpu is falling back to different first chunk allocator. Make it clear static buffers so that they don't contain values from previous runs. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-09-29percpu: fix unit_map[] verification in pcpu_setup_first_chunk()Tejun Heo
pcpu_setup_first_chunk() incorrectly used NR_CPUS as the impossible unit number while unit number can equal and go over NR_CPUS with sparse unit map. This triggers BUG_ON() spuriously on machines which have non-power-of-two number of cpus. Use UINT_MAX instead. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-and-tested-by: Tony Vroon <tony@linx.net>
2009-09-27const: mark struct vm_struct_operationsAlexey Dobriyan
* mark struct vm_area_struct::vm_ops as const * mark vm_ops in AGP code But leave TTM code alone, something is fishy there with global vm_ops being used. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-27x86: Fix hwpoison code related build failure on 32-bit NUMAQLinus Torvalds
This build failure triggers: In file included from include/linux/suspend.h:8, from arch/x86/kernel/asm-offsets_32.c:11, from arch/x86/kernel/asm-offsets.c:2: include/linux/mm.h:503:2: error: #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS Because due to the hwpoison page flag we ran out of page flags on 32-bit. Dont turn on hwpoison on 32-bit NUMA (it's rare in any case). Also clean up the Kconfig dependencies in the generic MM code by introducing ARCH_SUPPORTS_MEMORY_FAILURE. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-26writeback: pass in super_block to bdi_start_writeback()Jens Axboe
Sometimes we only want to write pages from a specific super_block, so allow that to be passed in. This fixes a problem with commit 56a131dcf7ed36c3c6e36bea448b674ea85ed5bb causing writeback on all super_blocks on a bdi, where we only really want to sync a specific sb from writeback_inodes_sb(). Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'writeback' of git://git.kernel.dk/linux-2.6-block: writeback: writeback_inodes_sb() should use bdi_start_writeback() writeback: don't delay inodes redirtied by a fast dirtier writeback: make the super_block pinning more efficient writeback: don't resort for a single super_block in move_expired_inodes() writeback: move inodes from one super_block together writeback: get rid to incorrect references to pdflush in comments writeback: improve readability of the wb_writeback() continue/break logic writeback: cleanup writeback_single_inode() writeback: kupdate writeback shall not stop when more io is possible writeback: stop background writeback when below background threshold writeback: balance_dirty_pages() shall write more than dirtied pages fs: Fix busyloop in wb_writeback()
2009-09-25writeback: get rid to incorrect references to pdflush in commentsJens Axboe
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25writeback: stop background writeback when below background thresholdWu Fengguang
Treat bdi_start_writeback(0) as a special request to do background write, and stop such work when we are below the background dirty threshold. Also simplify the (nr_pages <= 0) checks. Since we already pass in nr_pages=LONG_MAX for WB_SYNC_ALL and background writes, we don't need to worry about it being decreased to zero. Reported-by: Richard Kennedy <richard@rsk.demon.co.uk> CC: Jan Kara <jack@suse.cz> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25writeback: balance_dirty_pages() shall write more than dirtied pagesWu Fengguang
Some filesystem may choose to write much more than ratelimit_pages before calling balance_dirty_pages_ratelimited_nr(). So it is safer to determine number to write based on real number of dirtied pages. Otherwise it is possible that loop { btrfs_file_write(): dirty 1024 pages balance_dirty_pages(): write up to 48 pages (= ratelimit_pages * 1.5) } in which the writeback rate cannot keep up with dirty rate, and the dirty pages go all the way beyond dirty_thresh. The increased write_chunk may make the dirtier more bumpy. So filesystems shall be take care not to dirty too much at a time (eg. > 4MB) without checking the ratelimit. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-24NOMMU: Ignore mmap() address param as it is a hintDavid Howells
Ignore the address parameter given to NOMMU mmap() as it is a hint, rather than giving an error if it's non-zero. MAP_FIXED still gets an error. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24NOMMU: Fix MAP_PRIVATE mmap() of objects where the data can be mapped directlyDavid Howells
Fix MAP_PRIVATE mmap() of files and devices where the data in the backing store might be mapped directly. Use the BDI_CAP_MAP_DIRECT capability flag to govern whether or not we should be trying to map a file directly. This can be used to determine whether or not a region has been filled in at the point where we call do_mmap_shared() or do_mmap_private(). The BDI_CAP_MAP_DIRECT capability flag is cleared by validate_mmap_request() if there's any reason we can't use it. It's also cleared in do_mmap_pgoff() if f_op->get_unmapped_area() fails. Without this fix, attempting to run a program from a RomFS image on a non-mappable MTD partition results in a BUG as the kernel attempts XIP, and this can be caught in gdb: Program received signal SIGABRT, Aborted. 0xc005dce8 in add_nommu_region (region=<value optimized out>) at mm/nommu.c:547 (gdb) bt #0 0xc005dce8 in add_nommu_region (region=<value optimized out>) at mm/nommu.c:547 #1 0xc005f168 in do_mmap_pgoff (file=0xc31a6620, addr=<value optimized out>, len=3808, prot=3, flags=6146, pgoff=0) at mm/nommu.c:1373 #2 0xc00a96b8 in elf_fdpic_map_file (params=0xc33fbbec, file=0xc31a6620, mm=0xc31bef60, what=0xc0213144 "executable") at mm.h:1145 #3 0xc00aa8b4 in load_elf_fdpic_binary (bprm=0xc316cb00, regs=<value optimized out>) at fs/binfmt_elf_fdpic.c:343 #4 0xc006b588 in search_binary_handler (bprm=0x6, regs=0xc33fbce0) at fs/exec.c:1234 #5 0xc006c648 in do_execve (filename=<value optimized out>, argv=0xc3ad14cc, envp=0xc3ad1460, regs=0xc33fbce0) at fs/exec.c:1356 #6 0xc0008cf0 in sys_execve (name=<value optimized out>, argv=0xc3ad14cc, envp=0xc3ad1460) at arch/frv/kernel/process.c:263 #7 0xc00075dc in __syscall_call () at arch/frv/kernel/entry.S:897 Note that this fix does the following commit differently: commit a190887b58c32d19c2eee007c5eb8faa970a69ba Author: David Howells <dhowells@redhat.com> Date: Sat Sep 5 11:17:07 2009 -0700 nommu: fix error handling in do_mmap_pgoff() Reported-by: Graff Yang <graff.yang@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24procfs: disable per-task stack usage on NOMMUAndrew Morton
It needs walk_page_range(). Reported-by: Michal Simek <monstr@monstr.eu> Tested-by: Michal Simek <monstr@monstr.eu> Cc: Stefani Seibold <stefani@seibold.net> Cc: David Howells <dhowells@redhat.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: truncate: use new helpers truncate: new helpers fs: fix overflow in sys_mount() for in-kernel calls fs: Make unload_nls() NULL pointer safe freeze_bdev: grab active reference to frozen superblocks freeze_bdev: kill bd_mount_sem exofs: remove BKL from super operations fs/romfs: correct error-handling code vfs: seq_file: add helpers for data filling vfs: remove redundant position check in do_sendfile vfs: change sb->s_maxbytes to a loff_t vfs: explicitly cast s_maxbytes in fiemap_check_ranges libfs: return error code on failed attr set seq_file: return a negative error code when seq_path_root() fails. vfs: optimize touch_time() too vfs: optimization for touch_atime() vfs: split generic_forget_inode() so that hugetlbfs does not have to copy it fs/inode.c: add dev-id and inode number for debugging in init_special_inode() libfs: make simple_read_from_buffer conventional
2009-09-24Merge branch 'hwpoison' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 * 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (21 commits) HWPOISON: Enable error_remove_page on btrfs HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs HWPOISON: Add madvise() based injector for hardware poisoned pages v4 HWPOISON: Enable error_remove_page for NFS HWPOISON: Enable .remove_error_page for migration aware file systems HWPOISON: The high level memory error handler in the VM v7 HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process HWPOISON: shmem: call set_page_dirty() with locked page HWPOISON: Define a new error_remove_page address space op for async truncation HWPOISON: Add invalidate_inode_page HWPOISON: Refactor truncate to allow direct truncating of page v2 HWPOISON: check and isolate corrupted free pages v2 HWPOISON: Handle hardware poisoned pages in try_to_unmap HWPOISON: Use bitmask/action code for try_to_unmap behaviour HWPOISON: x86: Add VM_FAULT_HWPOISON handling to x86 page fault handler v2 HWPOISON: Add poison check to page fault handling HWPOISON: Add basic support for poisoned pages in fault handler v3 HWPOISON: Add new SIGBUS error codes for hardware poison signals HWPOISON: Add support for poison swap entries v2 HWPOISON: Export some rmap vma locking to outside world ...
2009-09-24sysctl: remove "struct file *" argument of ->proc_handlerAlexey Dobriyan
It's unused. It isn't needed -- read or write flag is already passed and sysctl shouldn't care about the rest. It _was_ used in two places at arch/frv for some reason. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24memcg: show swap usage in stat fileDaisuke Nishimura
We now count MEM_CGROUP_STAT_SWAPOUT, so we can show swap usage. It would be useful for users to show swap usage in memory.stat file, because they don't need calculate memsw.usage - res.usage to know swap usage. Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Balbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24memcg: improve resource counter scalabilityBalbir Singh
Reduce the resource counter overhead (mostly spinlock) associated with the root cgroup. This is a part of the several patches to reduce mem cgroup overhead. I had posted other approaches earlier (including using percpu counters). Those patches will be a natural addition and will be added iteratively on top of these. The patch stops resource counter accounting for the root cgroup. The data for display is derived from the statisitcs we maintain via mem_cgroup_charge_statistics (which is more scalable). What happens today is that, we do double accounting, once using res_counter_charge() and once using memory_cgroup_charge_statistics(). For the root, since we don't implement limits any more, we don't need to track every charge via res_counter_charge() and check for limit being exceeded and reclaim. The main mem->res usage_in_bytes can be derived by summing the cache and rss usage data from memory statistics (MEM_CGROUP_STAT_RSS and MEM_CGROUP_STAT_CACHE). However, for memsw->res usage_in_bytes, we need additional data about swapped out memory. This patch adds a MEM_CGROUP_STAT_SWAPOUT and uses that along with MEM_CGROUP_STAT_RSS and MEM_CGROUP_STAT_CACHE to derive the memsw data. This data is computed recursively when hierarchy is enabled. The tests results I see on a 24 way show that 1. The lock contention disappears from /proc/lock_stats 2. The results of the test are comparable to running with cgroup_disable=memory. Here is a sample of my program runs Without Patch Performance counter stats for '/home/balbir/parallel_pagefault': 7192804.124144 task-clock-msecs # 23.937 CPUs 424691 context-switches # 0.000 M/sec 267 CPU-migrations # 0.000 M/sec 28498113 page-faults # 0.004 M/sec 5826093739340 cycles # 809.989 M/sec 408883496292 instructions # 0.070 IPC 7057079452 cache-references # 0.981 M/sec 3036086243 cache-misses # 0.422 M/sec 300.485365680 seconds time elapsed With cgroup_disable=memory Performance counter stats for '/home/balbir/parallel_pagefault': 7182183.546587 task-clock-msecs # 23.915 CPUs 425458 context-switches # 0.000 M/sec 203 CPU-migrations # 0.000 M/sec 92545093 page-faults # 0.013 M/sec 6034363609986 cycles # 840.185 M/sec 437204346785 instructions # 0.072 IPC 6636073192 cache-references # 0.924 M/sec 2358117732 cache-misses # 0.328 M/sec 300.320905827 seconds time elapsed With this patch applied Performance counter stats for '/home/balbir/parallel_pagefault': 7191619.223977 task-clock-msecs # 23.955 CPUs 422579 context-switches # 0.000 M/sec 88 CPU-migrations # 0.000 M/sec 91946060 page-faults # 0.013 M/sec 5957054385619 cycles # 828.333 M/sec 1058117350365 instructions # 0.178 IPC 9161776218 cache-references # 1.274 M/sec 1920494280 cache-misses # 0.267 M/sec 300.218764862 seconds time elapsed Data from Prarit (kernel compile with make -j64 on a 64 CPU/32G machine) For a single run Without patch real 27m8.988s user 87m24.916s sys 382m6.037s With patch real 4m18.607s user 84m58.943s sys 50m52.682s With config turned off real 4m54.972s user 90m13.456s sys 50m19.711s NOTE: The data looks counterintuitive due to the increased performance with the patch, even over the config being turned off. We probably need more runs, but so far all testing has shown that the patches definitely help. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24memory controller: soft limit reclaim on contentionBalbir Singh
Implement reclaim from groups over their soft limit Permit reclaim from memory cgroups on contention (via the direct reclaim path). memory cgroup soft limit reclaim finds the group that exceeds its soft limit by the largest number of pages and reclaims pages from it and then reinserts the cgroup into its correct place in the rbtree. Add additional checks to mem_cgroup_hierarchical_reclaim() to detect long loops in case all swap is turned off. The code has been refactored and the loop check (loop < 2) has been enhanced for soft limits. For soft limits, we try to do more targetted reclaim. Instead of bailing out after two loops, the routine now reclaims memory proportional to the size by which the soft limit is exceeded. The proportion has been empirically determined. [akpm@linux-foundation.org: build fix] [kamezawa.hiroyu@jp.fujitsu.com: fix softlimit css refcnt handling] [nishimura@mxp.nes.nec.co.jp: refcount of the "victim" should be decremented before exiting the loop] Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24memory controller: soft limit refactor reclaim flagsBalbir Singh
Refactor mem_cgroup_hierarchical_reclaim() Refactor the arguments passed to mem_cgroup_hierarchical_reclaim() into flags, so that new parameters don't have to be passed as we make the reclaim routine more flexible Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Li Zefan <lizf@cn.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>
2009-09-24memory controller: soft limit organize cgroupsBalbir Singh
Organize cgroups over soft limit in a RB-Tree Introduce an RB-Tree for storing memory cgroups that are over their soft limit. The overall goal is to 1. Add a memory cgroup to the RB-Tree when the soft limit is exceeded. We are careful about updates, updates take place only after a particular time interval has passed 2. We remove the node from the RB-Tree when the usage goes below the soft limit The next set of patches will exploit the RB-Tree to get the group that is over its soft limit by the largest amount and reclaim from it, when we face memory contention. [hugh.dickins@tiscali.co.uk: CONFIG_CGROUP_MEM_RES_CTLR=y CONFIG_PREEMPT=y fails to boot] Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24memory controller: soft limit interfaceBalbir Singh
Add an interface to allow get/set of soft limits. Soft limits for memory plus swap controller (memsw) is currently not supported. Resource counters have been enhanced to support soft limits and new type RES_SOFT_LIMIT has been added. Unlike hard limits, soft limits can be directly set and do not need any reclaim or checks before setting them to a newer value. Kamezawa-San raised a question as to whether soft limit should belong to res_counter. Since all resources understand the basic concepts of hard and soft limits, it is justified to add soft limits here. Soft limits are a generic resource usage feature, even file system quotas support soft limits. Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Li Zefan <lizf@cn.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>
2009-09-24memcg: add comments explaining memory barriersKAMEZAWA Hiroyuki
Add comments for the reason of smp_wmb() in mem_cgroup_commit_charge(). [akpm@linux-foundation.org: coding-style fixes] Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: 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>