summaryrefslogtreecommitdiff
path: root/mm
AgeCommit message (Collapse)Author
2011-12-13Basic kernel memory functionality for the Memory ControllerGlauber Costa
This patch lays down the foundation for the kernel memory component of the Memory Controller. As of today, I am only laying down the following files: * memory.independent_kmem_limit * memory.kmem.limit_in_bytes (currently ignored) * memory.kmem.usage_in_bytes (always zero) Signed-off-by: Glauber Costa <glommer@parallels.com> CC: Kirill A. Shutemov <kirill@shutemov.name> CC: Paul Menage <paul@paulmenage.org> CC: Greg Thelen <gthelen@google.com> CC: Johannes Weiner <jweiner@redhat.com> CC: Michal Hocko <mhocko@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09mm: vmalloc: check for page allocation failure before vmlist insertionMel Gorman
Commit f5252e00 ("mm: avoid null pointer access in vm_struct via /proc/vmallocinfo") adds newly allocated vm_structs to the vmlist after it is fully initialised. Unfortunately, it did not check that __vmalloc_area_node() successfully populated the area. In the event of allocation failure, the vmalloc area is freed but the pointer to freed memory is inserted into the vmlist leading to a a crash later in get_vmalloc_info(). This patch adds a check for ____vmalloc_area_node() failure within __vmalloc_node_range. It does not use "goto fail" as in the previous error path as a warning was already displayed by __vmalloc_area_node() before it called vfree in its failure path. Credit goes to Luciano Chavez for doing all the real work of identifying exactly where the problem was. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com> Tested-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> [3.1.x+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09mm: Ensure that pfn_valid() is called once per pageblock when reserving ↵Michal Hocko
pageblocks setup_zone_migrate_reserve() expects that zone->start_pfn starts at pageblock_nr_pages aligned pfn otherwise we could access beyond an existing memblock resulting in the following panic if CONFIG_HOLES_IN_ZONE is not configured and we do not check pfn_valid: IP: [<c02d331d>] setup_zone_migrate_reserve+0xcd/0x180 *pdpt = 0000000000000000 *pde = f000ff53f000ff53 Oops: 0000 [#1] SMP Pid: 1, comm: swapper Not tainted 3.0.7-0.7-pae #1 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform EIP: 0060:[<c02d331d>] EFLAGS: 00010006 CPU: 0 EIP is at setup_zone_migrate_reserve+0xcd/0x180 EAX: 000c0000 EBX: f5801fc0 ECX: 000c0000 EDX: 00000000 ESI: 000c01fe EDI: 000c01fe EBP: 00140000 ESP: f2475f58 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 Process swapper (pid: 1, ti=f2474000 task=f2472cd0 task.ti=f2474000) Call Trace: [<c02d389c>] __setup_per_zone_wmarks+0xec/0x160 [<c02d3a1f>] setup_per_zone_wmarks+0xf/0x20 [<c08a771c>] init_per_zone_wmark_min+0x27/0x86 [<c020111b>] do_one_initcall+0x2b/0x160 [<c086639d>] kernel_init+0xbe/0x157 [<c05cae26>] kernel_thread_helper+0x6/0xd Code: a5 39 f5 89 f7 0f 46 fd 39 cf 76 40 8b 03 f6 c4 08 74 32 eb 91 90 89 c8 c1 e8 0e 0f be 80 80 2f 86 c0 8b 14 85 60 2f 86 c0 89 c8 <2b> 82 b4 12 00 00 c1 e0 05 03 82 ac 12 00 00 8b 00 f6 c4 08 0f EIP: [<c02d331d>] setup_zone_migrate_reserve+0xcd/0x180 SS:ESP 0068:f2475f58 CR2: 00000000000012b4 We crashed in pageblock_is_reserved() when accessing pfn 0xc0000 because highstart_pfn = 0x36ffe. The issue was introduced in 3.0-rc1 by 6d3163ce ("mm: check if any page in a pageblock is reserved before marking it MIGRATE_RESERVE"). Make sure that start_pfn is always aligned to pageblock_nr_pages to ensure that pfn_valid s always called at the start of each pageblock. Architectures with holes in pageblocks will be correctly handled by pfn_valid_within in pageblock_is_reserved. Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Dang Bo <bdang@vmware.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Arve Hjnnevg <arve@android.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> [3.0+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09mm/migrate.c: pair unlock_page() and lock_page() when migrating huge pagesHillf Danton
Avoid unlocking and unlocked page if we failed to lock it. Signed-off-by: Hillf Danton <dhillf@gmail.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.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>
2011-12-09thp: set compound tail page _count to zeroYouquan Song
Commit 70b50f94f1644 ("mm: thp: tail page refcounting fix") keeps all page_tail->_count zero at all times. But the current kernel does not set page_tail->_count to zero if a 1GB page is utilized. So when an IOMMU 1GB page is used by KVM, it wil result in a kernel oops because a tail page's _count does not equal zero. kernel BUG at include/linux/mm.h:386! invalid opcode: 0000 [#1] SMP Call Trace: gup_pud_range+0xb8/0x19d get_user_pages_fast+0xcb/0x192 ? trace_hardirqs_off+0xd/0xf hva_to_pfn+0x119/0x2f2 gfn_to_pfn_memslot+0x2c/0x2e kvm_iommu_map_pages+0xfd/0x1c1 kvm_iommu_map_memslots+0x7c/0xbd kvm_iommu_map_guest+0xaa/0xbf kvm_vm_ioctl_assigned_device+0x2ef/0xa47 kvm_vm_ioctl+0x36c/0x3a2 do_vfs_ioctl+0x49e/0x4e4 sys_ioctl+0x5a/0x7c system_call_fastpath+0x16/0x1b RIP gup_huge_pud+0xf2/0x159 Signed-off-by: Youquan Song <youquan.song@intel.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09thp: reduce khugepaged freezing latencyAndrea Arcangeli
khugepaged can sometimes cause suspend to fail, requiring that the user retry the suspend operation. Use wait_event_freezable_timeout() instead of schedule_timeout_interruptible() to avoid missing freezer wakeups. A try_to_freeze() would have been needed in the khugepaged_alloc_hugepage tight loop too in case of the allocation failing repeatedly, and wait_event_freezable_timeout will provide it too. khugepaged would still freeze just fine by trying again the next minute but it's better if it freezes immediately. Reported-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Tested-by: Jiri Slaby <jslaby@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Cc: "Rafael J. Wysocki" <rjw@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09vmscan: use atomic-long for shrinker batchingKonstantin Khlebnikov
Use atomic-long operations instead of looping around cmpxchg(). [akpm@linux-foundation.org: massage atomic.h inclusions] Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09vmscan: fix initial shrinker size handlingKonstantin Khlebnikov
A shrinker function can return -1, means that it cannot do anything without a risk of deadlock. For example prune_super() does this if it cannot grab a superblock refrence, even if nr_to_scan=0. Currently we interpret this -1 as a ULONG_MAX size shrinker and evaluate `total_scan' according to this. So the next time around this shrinker can cause really big pressure. Let's skip such shrinkers instead. Also make total_scan signed, otherwise the check (total_scan < 0) below never works. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-08memblock: Reimplement memblock allocation using reverse free area iteratorTejun Heo
Now that all early memory information is in memblock when enabled, we can implement reverse free area iterator and use it to implement NUMA aware allocator which is then wrapped for simpler variants instead of the confusing and inefficient mending of information in separate NUMA aware allocator. Implement for_each_free_mem_range_reverse(), use it to reimplement memblock_find_in_range_node() which in turn is used by all allocators. The visible allocator interface is inconsistent and can probably use some cleanup too. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Kill early_node_map[]Tejun Heo
Now all ARCH_POPULATES_NODE_MAP archs select HAVE_MEBLOCK_NODE_MAP - there's no user of early_node_map[] left. Kill early_node_map[] and replace ARCH_POPULATES_NODE_MAP with HAVE_MEMBLOCK_NODE_MAP. Also, relocate for_each_mem_pfn_range() and helper from mm.h to memblock.h as page_alloc.c would no longer host an alternative implementation. This change is ultimately one to one mapping and shouldn't cause any observable difference; however, after the recent changes, there are some functions which now would fit memblock.c better than page_alloc.c and dependency on HAVE_MEMBLOCK_NODE_MAP instead of HAVE_MEMBLOCK doesn't make much sense on some of them. Further cleanups for functions inside HAVE_MEMBLOCK_NODE_MAP in mm.h would be nice. -v2: Fix compile bug introduced by mis-spelling CONFIG_HAVE_MEMBLOCK_NODE_MAP to CONFIG_MEMBLOCK_HAVE_NODE_MAP in mmzone.h. Reported by Stephen Rothwell. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "H. Peter Anvin" <hpa@zytor.com>
2011-12-08memblock: Implement memblock_add_node()Tejun Heo
Implement memblock_add_node() which can add a new memblock memory region with specific node ID. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: s/memblock_analyze()/memblock_allow_resize()/ and update usersTejun Heo
The only function of memblock_analyze() is now allowing resize of memblock region arrays. Rename it to memblock_allow_resize() and update its users. * The following users remain the same other than renaming. arm/mm/init.c::arm_memblock_init() microblaze/kernel/prom.c::early_init_devtree() powerpc/kernel/prom.c::early_init_devtree() openrisc/kernel/prom.c::early_init_devtree() sh/mm/init.c::paging_init() sparc/mm/init_64.c::paging_init() unicore32/mm/init.c::uc32_memblock_init() * In the following users, analyze was used to update total size which is no longer necessary. powerpc/kernel/machine_kexec.c::reserve_crashkernel() powerpc/kernel/prom.c::early_init_devtree() powerpc/mm/init_32.c::MMU_init() powerpc/mm/tlb_nohash.c::__early_init_mmu() powerpc/platforms/ps3/mm.c::ps3_mm_add_memory() powerpc/platforms/embedded6xx/wii.c::wii_memory_fixups() sh/kernel/machine_kexec.c::reserve_crashkernel() * x86/kernel/e820.c::memblock_x86_fill() was directly setting memblock_can_resize before populating memblock and calling analyze afterwards. Call memblock_allow_resize() before start populating. memblock_can_resize is now static inside memblock.c. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Michal Simek <monstr@monstr.eu> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: "H. Peter Anvin" <hpa@zytor.com>
2011-12-08memblock: Track total size of regions automaticallyTejun Heo
Total size of memory regions was calculated by memblock_analyze() requiring explicitly calling the function between operations which can change memory regions and possible users of total size, which is cumbersome and fragile. This patch makes each memblock_type track total size automatically with minor modifications to memblock manipulation functions and remove requirements on calling memblock_analyze(). [__]memblock_dump_all() now also dumps the total size of reserved regions. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Reimplement memblock_enforce_memory_limit() using __memblock_remove()Tejun Heo
With recent updates, the basic memblock operations are robust enough that there's no reason for memblock_enfore_memory_limit() to directly manipulate memblock region arrays. Reimplement it using __memblock_remove(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Make memblock functions handle overflowing range @sizeTejun Heo
Allow memblock users to specify range where @base + @size overflows and automatically cap it at maximum. This makes the interface more robust and specifying till-the-end-of-memory easier. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Reimplement __memblock_remove() using memblock_isolate_range()Tejun Heo
__memblock_remove()'s open coded region manipulation can be trivially replaced with memblock_islate_range(). This increases code sharing and eases improving region tracking. This pulls memblock_isolate_range() out of HAVE_MEMBLOCK_NODE_MAP. Make it use memblock_get_region_node() instead of assuming rgn->nid is available. -v2: Fixed build failure on !HAVE_MEMBLOCK_NODE_MAP caused by direct rgn->nid access. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Separate out memblock_isolate_range() from memblock_set_node()Tejun Heo
memblock_set_node() operates in three steps - break regions crossing boundaries, set nid and merge back regions. This patch separates the first part into a separate function - memblock_isolate_range(), which breaks regions crossing range boundaries and returns range index range for regions properly contained in the specified memory range. This doesn't introduce any behavior change and will be used to further unify region handling. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Kill memblock_init()Tejun Heo
memblock_init() initializes arrays for regions and memblock itself; however, all these can be done with struct initializers and memblock_init() can be removed. This patch kills memblock_init() and initializes memblock with struct initializer. The only difference is that the first dummy entries don't have .nid set to MAX_NUMNODES initially. This doesn't cause any behavior difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Michal Simek <monstr@monstr.eu> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: "H. Peter Anvin" <hpa@zytor.com>
2011-12-08memblock: Kill sentinel entries at the end of static region arraysTejun Heo
memblock no longer depends on having one more entry at the end during addition making the sentinel entries at the end of region arrays not too useful. Remove the sentinels. This eases further updates. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Add __memblock_dump_all()Tejun Heo
Add __memblock_dump_all() which dumps memblock configuration whether memblock_debug is enabled or not. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Use memblock_reserve() in memblock internal functionsTejun Heo
Make memblock_double_array(), __memblock_alloc_base() and memblock_alloc_nid() use memblock_reserve() instead of calling memblock_add_region() with reserved array directly. This eases debugging and updates to memblock_add_region(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08memblock: Make memblock_{add|remove|free|reserve}() return int and update ↵Tejun Heo
prototypes memblock_{add|remove|free|reserve}() return either 0 or -errno but had long as return type. Chage it to int. Also, drop 'extern' from all prototypes in memblock.h - they are unnecessary and used inconsistently (especially if mm.h is included in the picture). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08writeback: set max_pause to lowest value on zero bdi_dirtyWu Fengguang
Some trace shows lots of bdi_dirty=0 lines where it's actually some small value if w/o the accounting errors in the per-cpu bdi stats. In this case the max pause time should really be set to the smallest (non-zero) value to avoid IO queue underrun and improve throughput. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-08writeback: permit through good bdi even when global dirty exceededWu Fengguang
On a system with 1 local mount and 1 NFS mount, if the NFS server becomes not responding when dd to the NFS mount, the NFS dirty pages may exceed the global dirty limit and _every_ task involving writing will be blocked. The whole system appears unresponsive. The workaround is to permit through the bdi's that only has a small number of dirty pages. The number chosen (bdi_stat_error pages) is not enough to enable the local disk to run in optimal throughput, however is enough to make the system responsive on a broken NFS mount. The user can then kill the dirtiers on the NFS mount and increase the global dirty limit to bring up the local disk's throughput. It risks allowing dirty pages to grow much larger than the global dirty limit when there are 1000+ mounts, however that's very unlikely to happen, especially in low memory profiles. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-08writeback: comment on the bdi dirty thresholdWu Fengguang
We do "floating proportions" to let active devices to grow its target share of dirty pages and stalled/inactive devices to decrease its target share over time. It works well except in the case of "an inactive disk suddenly goes busy", where the initial target share may be too small. To mitigate this, bdi_position_ratio() has the below line to raise a small bdi_thresh when it's safe to do so, so that the disk be feed with enough dirty pages for efficient IO and in turn fast rampup of bdi_thresh: bdi_thresh = max(bdi_thresh, (limit - dirty) / 8); balance_dirty_pages() normally does negative feedback control which adjusts ratelimit to balance the bdi dirty pages around the target. In some extreme cases when that is not enough, it will have to block the tasks completely until the bdi dirty pages drop below bdi_thresh. Acked-by: Jan Kara <jack@suse.cz> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-05Merge branch 'vmalloc' of git://git.linaro.org/people/nico/linux into ↵Russell King
devel-stable
2011-12-05slab, lockdep: Fix silly bugPeter Zijlstra
Commit 30765b92 ("slab, lockdep: Annotate the locks before using them") moves the init_lock_keys() call from after g_cpucache_up = FULL, to before it. And overlooks the fact that init_node_lock_keys() tests for it and ignores everything !FULL. Introduce a LATE stage and change the lockdep test to be <LATE. Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: stable@kernel.org Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-02fs: Make write(2) interruptible by a fatal signalJan Kara
Currently write(2) to a file is not interruptible by any signal. Sometimes this is desirable, e.g. when you want to quickly kill a process hogging your disk. Also, with commit 499d05ecf990 ("mm: Make task in balance_dirty_pages() killable"), it's necessary to abort the current write accordingly to avoid it quickly dirtying lots more pages at unthrottled rate. This patch makes write interruptible by SIGKILL. We do not allow write to be interruptible by any other signal because that has larger potential of screwing some badly written applications. Reported-by: Kazuya Mio <k-mio@sx.jp.nec.com> Tested-by: Kazuya Mio <k-mio@sx.jp.nec.com> Acked-by: Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-11-29Merge branch 'slab/urgent' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux * 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux: slub: avoid potential NULL dereference or corruption slub: use irqsafe_cpu_cmpxchg for put_cpu_partial slub: move discard_slab out of node lock slub: use correct parameter to add a page to partial list tail
2011-11-28Merge branch 'for-3.2-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-3.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: percpu: explain why per_cpu_ptr_to_phys() is more complicated than necessary percpu: fix chunk range calculation percpu: rename pcpu_mem_alloc to pcpu_mem_zalloc
2011-11-28Merge branch 'master' into x86/memblockTejun Heo
Conflicts & resolutions: * arch/x86/xen/setup.c dc91c728fd "xen: allow extra memory to be in multiple regions" 24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..." conflicted on xen_add_extra_mem() updates. The resolution is trivial as the latter just want to replace memblock_x86_reserve_range() with memblock_reserve(). * drivers/pci/intel-iommu.c 166e9278a3f "x86/ia64: intel-iommu: move to drivers/iommu/" 5dfe8660a3d "bootmem: Replace work_with_active_regions() with..." conflicted as the former moved the file under drivers/iommu/. Resolved by applying the chnages from the latter on the moved file. * mm/Kconfig 6661672053a "memblock: add NO_BOOTMEM config symbol" c378ddd53f9 "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option" conflicted trivially. Both added config options. Just letting both add their own options resolves the conflict. * mm/memblock.c d1f0ece6cdc "mm/memblock.c: small function definition fixes" ed7b56a799c "memblock: Remove memblock_memory_can_coalesce()" confliected. The former updates function removed by the latter. Resolution is trivial. Signed-off-by: Tejun Heo <tj@kernel.org>
2011-11-24slub: avoid potential NULL dereference or corruptionEric Dumazet
show_slab_objects() can trigger NULL dereferences or memory corruption. Another cpu can change its c->page to NULL or c->node to NUMA_NO_NODE while we use them. Use ACCESS_ONCE(c->page) and ACCESS_ONCE(c->node) to make sure this cannot happen. Acked-by: Christoph Lameter <cl@linux.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-11-24slub: use irqsafe_cpu_cmpxchg for put_cpu_partialChristoph Lameter
The cmpxchg must be irq safe. The fallback for this_cpu_cmpxchg only disables preemption which results in per cpu partial page operation potentially failing on non x86 platforms. This patch fixes the following problem reported by Christian Kujau: I seem to hit it with heavy disk & cpu IO is in progress on this PowerBook G4. Full dmesg & .config: http://nerdbynature.de/bits/3.2.0-rc1/oops/ I've enabled some debug options and now it really points to slub.c:2166 http://nerdbynature.de/bits/3.2.0-rc1/oops/oops4m.jpg With debug options enabled I'm currently in the xmon debugger, not sure what to make of it yet, I'll try to get something useful out of it :) Reported-by: Christian Kujau <lists@nerdbynature.de> Tested-by: Christian Kujau <lists@nerdbynature.de> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-11-23Merge branch 'pm-freezer' of ↵Rafael J. Wysocki
git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into pm-freezer * 'pm-freezer' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc: (24 commits) freezer: fix wait_event_freezable/__thaw_task races freezer: kill unused set_freezable_with_signal() dmatest: don't use set_freezable_with_signal() usb_storage: don't use set_freezable_with_signal() freezer: remove unused @sig_only from freeze_task() freezer: use lock_task_sighand() in fake_signal_wake_up() freezer: restructure __refrigerator() freezer: fix set_freezable[_with_signal]() race freezer: remove should_send_signal() and update frozen() freezer: remove now unused TIF_FREEZE freezer: make freezing() test freeze conditions in effect instead of TIF_FREEZE cgroup_freezer: prepare for removal of TIF_FREEZE freezer: clean up freeze_processes() failure path freezer: kill PF_FREEZING freezer: test freezable conditions while holding freezer_lock freezer: make freezing indicate freeze condition in effect freezer: use dedicated lock instead of task_lock() + memory barrier freezer: don't distinguish nosig tasks on thaw freezer: remove racy clear_freeze_flag() and set PF_NOFREEZE on dead tasks freezer: rename thaw_process() to __thaw_task() and simplify the implementation ...
2011-11-23percpu: explain why per_cpu_ptr_to_phys() is more complicated than necessaryDave Young
Add comments about current per_cpu_ptr_to_phys implementation to explain why the logic is more complicated than necessary. -tj: relocated comment into kerneldoc comment Signed-off-by: Dave Young <dyoung@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2011-11-22Merge branch 'writeback-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux * 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: remove vm_dirties and task->dirties writeback: hard throttle 1000+ dd on a slow USB stick mm: Make task in balance_dirty_pages() killable
2011-11-22percpu: fix chunk range calculationTejun Heo
Percpu allocator recorded the cpus which map to the first and last units in pcpu_first/last_unit_cpu respectively and used them to determine the address range of a chunk - e.g. it assumed that the first unit has the lowest address in a chunk while the last unit has the highest address. This simply isn't true. Groups in a chunk can have arbitrary positive or negative offsets from the previous one and there is no guarantee that the first unit occupies the lowest offset while the last one the highest. Fix it by actually comparing unit offsets to determine cpus occupying the lowest and highest offsets. Also, rename pcu_first/last_unit_cpu to pcpu_low/high_unit_cpu to avoid confusion. The chunk address range is used to flush cache on vmalloc area map/unmap and decide whether a given address is in the first chunk by per_cpu_ptr_to_phys() and the bug was discovered by invalid per_cpu_ptr_to_phys() translation for crash_note. Kudos to Dave Young for tracking down the problem. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: WANG Cong <xiyou.wangcong@gmail.com> Reported-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> LKML-Reference: <4EC21F67.10905@redhat.com> Cc: stable @kernel.org
2011-11-22percpu: rename pcpu_mem_alloc to pcpu_mem_zallocBob Liu
Currently pcpu_mem_alloc() is implemented always return zeroed memory. So rename it to make user like pcpu_get_pages_and_bitmap() know don't reinit it. Signed-off-by: Bob Liu <lliubbo@gmail.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Tejun Heo <tj@kernel.org>
2011-11-21freezer: rename thaw_process() to __thaw_task() and simplify the implementationTejun Heo
thaw_process() now has only internal users - system and cgroup freezers. Remove the unnecessary return value, rename, unexport and collapse __thaw_process() into it. This will help further updates to the freezer code. -v3: oom_kill grew a use of thaw_process() while this patch was pending. Convert it to use __thaw_task() for now. In the longer term, this should be handled by allowing tasks to die if killed even if it's frozen. -v2: minor style update as suggested by Matt. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Paul Menage <menage@google.com> Cc: Matt Helsley <matthltc@us.ibm.com>
2011-11-21freezer: implement and use kthread_freezable_should_stop()Tejun Heo
Writeback and thinkpad_acpi have been using thaw_process() to prevent deadlock between the freezer and kthread_stop(); unfortunately, this is inherently racy - nothing prevents freezing from happening between thaw_process() and kthread_stop(). This patch implements kthread_freezable_should_stop() which enters refrigerator if necessary but is guaranteed to return if kthread_stop() is invoked. Both thaw_process() users are converted to use the new function. Note that this deadlock condition exists for many of freezable kthreads. They need to be converted to use the new should_stop or freezable workqueue. Tested with synthetic test case. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Henrique de Moraes Holschuh <ibm-acpi@hmh.eng.br> Cc: Jens Axboe <axboe@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com>
2011-11-18mm: add vm_area_add_early()Nicolas Pitre
The existing vm_area_register_early() allows for early vmalloc space allocation. However upcoming cleanups in the ARM architecture require that some fixed locations in the vmalloc area be reserved also very early. The name "vm_area_register_early" would have been a good name for the reservation part without the allocation. Since it is already in use with different semantics, let's create vm_area_add_early() instead. Both vm_area_register_early() and vm_area_add_early() can be used together meaning that the former is now implemented using the later where it is ensured that no conflicting areas are added, but no attempt is made to make the allocation scheme in vm_area_register_early() more sophisticated. After all, you must know what you're doing when using those functions. Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org> Acked-by: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mm@kvack.org
2011-11-18Merge branch 'stable/for-linus-fixes-3.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/for-linus-fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen-gntalloc: signedness bug in add_grefs() xen-gntalloc: integer overflow in gntalloc_ioctl_alloc() xen-gntdev: integer overflow in gntdev_alloc_map() xen:pvhvm: enable PVHVM VCPU placement when using more than 32 CPUs. xen/balloon: Avoid OOM when requesting highmem xen: Remove hanging references to CONFIG_XEN_PLATFORM_PCI xen: map foreign pages for shared rings by updating the PTEs directly
2011-11-18Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-block: block: add missed trace_block_plug paride: fix potential information leak in pg_read() bio: change some signed vars to unsigned block: avoid unnecessary plug list flush cciss: auto engage SCSI mid layer at driver load time loop: cleanup set_status interface include/linux/bio.h: use a static inline function for bio_integrity_clone() loop: prevent information leak after failed read block: Always check length of all iov entries in blk_rq_map_user_iov() The Windows driver .inf disables ASPM on all cciss devices. Do the same. backing-dev: ensure wakeup_timer is deleted block: Revert "[SCSI] genhd: add a new attribute "alias" in gendisk"
2011-11-17writeback: remove vm_dirties and task->dirtiesWu Fengguang
They are not used any more. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-11-17writeback: hard throttle 1000+ dd on a slow USB stickWu Fengguang
The sleep based balance_dirty_pages() can pause at most MAX_PAUSE=200ms on every 1 4KB-page, which means it cannot throttle a task under 4KB/200ms=20KB/s. So when there are more than 512 dd writing to a 10MB/s USB stick, its bdi dirty pages could grow out of control. Even if we can increase MAX_PAUSE, the minimal (task_ratelimit = 1) means a limit of 4KB/s. They can eventually be safeguarded by the global limit check (nr_dirty < dirty_thresh). However if someone is also writing to an HDD at the same time, it'll get poor HDD write performance. We at least want to maintain good write performance for other devices when one device is attacked by some "massive parallel" workload, or suffers from slow write bandwidth, or somehow get stalled due to some error condition (eg. NFS server not responding). For a stalled device, we need to completely block its dirtiers, too, before its bdi dirty pages grow all the way up to the global limit and leave no space for the other functional devices. So change the loop exit condition to /* * Always enforce global dirty limit; also enforce bdi dirty limit * if the normal max_pause sleeps cannot keep things under control. */ if (nr_dirty < dirty_thresh && (bdi_dirty < bdi_thresh || bdi->dirty_ratelimit > 1)) break; which can be further simplified to if (task_ratelimit) break; Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-11-17mm: cleanup the comment for head/tail pages of compound pages in mm/page_alloc.cWang Sheng-Hui
Only tail pages point at the head page using their ->first_page fields. Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-11-16xen: map foreign pages for shared rings by updating the PTEs directlyDavid Vrabel
When mapping a foreign page with xenbus_map_ring_valloc() with the GNTTABOP_map_grant_ref hypercall, set the GNTMAP_contains_pte flag and pass a pointer to the PTE (in init_mm). After the page is mapped, the usual fault mechanism can be used to update additional MMs. This allows the vmalloc_sync_all() to be removed from alloc_vm_area(). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> [v1: Squashed fix by Michal for no-mmu case] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2011-11-16mm: Make task in balance_dirty_pages() killableJan Kara
There is no reason why task in balance_dirty_pages() shouldn't be killable and it helps in recovering from some error conditions (like when filesystem goes in error state and cannot accept writeback anymore but we still want to kill processes using it to be able to unmount it). There will be follow up patches to further abort the generic_perform_write() and other filesystem write loops, to avoid large write + SIGKILL combination exceeding the dirty limit and possibly strange OOM. Reported-by: Kazuya Mio <k-mio@sx.jp.nec.com> Tested-by: Kazuya Mio <k-mio@sx.jp.nec.com> Reviewed-by: Neil Brown <neilb@suse.de> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-11-16hugetlb: release pages in the error path of hugetlb_cow()Hillf Danton
If we fail to prepare an anon_vma, the {new, old}_page should be released, or they will leak. Signed-off-by: Hillf Danton <dhillf@gmail.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <jweiner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-16oom: do not kill tasks with oom_score_adj OOM_SCORE_ADJ_MINMichal Hocko
Commit c9f01245 ("oom: remove oom_disable_count") has removed the oom_disable_count counter which has been used for early break out from oom_badness so we could never select a task with oom_score_adj set to OOM_SCORE_ADJ_MIN (oom disabled). Now that the counter is gone we are always going through heuristics calculation and we always return a non zero positive value. This means that we can end up killing a task with OOM disabled because it is indistinguishable from regular tasks with 1% resp. CAP_SYS_ADMIN tasks with 3% usage of memory or tasks with oom_score_adj set but OOM enabled. Let's break out early if the task should have OOM disabled. Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Oleg Nesterov <oleg@redhat.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>