mirror of
https://github.com/torvalds/linux.git
synced 2026-06-15 02:21:59 +02:00
f500da32a1
9768 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Minchan Kim
|
36abe7272a |
mm/hwpoison: fix wrong num_poisoned_pages accounting
commit
|
||
|
Minchan Kim
|
87c855f150 |
mm: vmscan: reclaim highmem zone if buffer_heads is over limit
commit |
||
|
Gerald Schaefer
|
e513b90a9a |
numa: fix /proc/<pid>/numa_maps for THP
commit
|
||
|
Konstantin Khlebnikov
|
be591a683e |
mm/huge_memory: replace VM_NO_THP VM_BUG_ON with actual VMA check
commit |
||
|
Tejun Heo
|
52526076a5 |
memcg: relocate charge moving from ->attach to ->post_attach
commit |
||
|
Jesper Dangaard Brouer
|
a4e25ff311 |
slub: clean up code for kmem cgroup support to kmem_cache_free_bulk
commit |
||
|
Xishi Qiu
|
fb4cfc6e0a |
mm: fix invalid node in alloc_migrate_target()
commit |
||
|
Vlastimil Babka
|
5dc7e939b6 |
mm/page_alloc: prevent merging between isolated and other pageblocks
commit |
||
|
Johannes Weiner
|
0ccab5b139 |
mm: memcontrol: reclaim and OOM kill when shrinking memory.max below usage
commit
|
||
|
Johannes Weiner
|
8b42fc47e1 |
mm: memcontrol: reclaim when shrinking memory.high below usage
commit
|
||
|
Al Viro
|
bcb1875a06 |
make sure that freeing shmem fast symlinks is RCU-delayed
commit
|
||
|
Minchan Kim
|
afb0299353 |
virtio_balloon: fix race between migration and ballooning
commit
|
||
|
Mel Gorman
|
18b75e0bdc |
mm: numa: quickly fail allocations for NUMA balancing on full nodes
commit |
||
|
Andrea Arcangeli
|
915d02457e |
mm: thp: fix SMP race condition between THP page fault and MADV_DONTNEED
commit
|
||
|
Vineet Gupta
|
edfde263bd |
mm,thp: khugepaged: call pte flush at the time of collapse
commit |
||
|
Martijn Coenen
|
ececa3ebe2 |
memcg: only free spare array when readers are done
commit
|
||
|
Kirill A. Shutemov
|
d1f8217a9a |
mm: fix regression in remap_file_pages() emulation
commit |
||
|
Konstantin Khlebnikov
|
413aab16bc |
mm: replace vma_lock_anon_vma with anon_vma_lock_read/write
commit
|
||
|
Kirill A. Shutemov
|
918a2c388e |
mm: fix mlock accouting
commit |
||
|
Naoya Horiguchi
|
bd55913cf2 |
mm: soft-offline: check return value in second __get_any_page() call
commit |
||
|
Jann Horn
|
969624b7c1 |
ptrace: use fsuid, fsgid, effective creds for fs access checks
commit
|
||
|
Tetsuo Handa
|
fe5c164ef3 |
mm, vmstat: fix wrong WQ sleep when memory reclaim doesn't make any progress
commit |
||
|
Junil Lee
|
bddaf79195 |
zsmalloc: fix migrate_zspage-zs_free race condition
commit
|
||
|
Michal Hocko
|
751e5f5c75 |
vmstat: allocate vmstat_wq before it is used
kernel test robot has reported the following crash:
BUG: unable to handle kernel NULL pointer dereference at 00000100
IP: [<c1074df6>] __queue_work+0x26/0x390
*pdpt = 0000000000000000 *pde = f000ff53f000ff53 *pde = f000ff53f000ff53
Oops: 0000 [#1] PREEMPT PREEMPT SMP SMP
CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.4.0-rc4-00139-g373ccbe #1
Workqueue: events vmstat_shepherd
task: cb684600 ti: cb7ba000 task.ti: cb7ba000
EIP: 0060:[<c1074df6>] EFLAGS: 00010046 CPU: 0
EIP is at __queue_work+0x26/0x390
EAX: 00000046 EBX: cbb37800 ECX: cbb37800 EDX: 00000000
ESI: 00000000 EDI: 00000000 EBP: cb7bbe68 ESP: cb7bbe38
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 00000100 CR3: 01fd5000 CR4: 000006b0
Stack:
Call Trace:
__queue_delayed_work+0xa1/0x160
queue_delayed_work_on+0x36/0x60
vmstat_shepherd+0xad/0xf0
process_one_work+0x1aa/0x4c0
worker_thread+0x41/0x440
kthread+0xb0/0xd0
ret_from_kernel_thread+0x21/0x40
The reason is that start_shepherd_timer schedules the shepherd work item
which uses vmstat_wq (vmstat_shepherd) before setup_vmstat allocates
that workqueue so if the further initialization takes more than HZ we
might end up scheduling on a NULL vmstat_wq. This is really unlikely
but not impossible.
Fixes:
|
||
|
Heiko Carstens
|
6cdb18ad98 |
mm/vmstat: fix overflow in mod_zone_page_state()
mod_zone_page_state() takes a "delta" integer argument. delta contains
the number of pages that should be added or subtracted from a struct
zone's vm_stat field.
If a zone is larger than 8TB this will cause overflows. E.g. for a
zone with a size slightly larger than 8TB the line
mod_zone_page_state(zone, NR_ALLOC_BATCH, zone->managed_pages);
in mm/page_alloc.c:free_area_init_core() will result in a negative
result for the NR_ALLOC_BATCH entry within the zone's vm_stat, since 8TB
contain 0x8xxxxxxx pages which will be sign extended to a negative
value.
Fix this by changing the delta argument to long type.
This could fix an early boot problem seen on s390, where we have a 9TB
system with only one node. ZONE_DMA contains 2GB and ZONE_NORMAL the
rest. The system is trying to allocate a GFP_DMA page but ZONE_DMA is
completely empty, so it tries to reclaim pages in an endless loop.
This was seen on a heavily patched 3.10 kernel. One possible
explaination seem to be the overflows caused by mod_zone_page_state().
Unfortunately I did not have the chance to verify that this patch
actually fixes the problem, since I don't have access to the system
right now. However the overflow problem does exist anyway.
Given the description that a system with slightly less than 8TB does
work, this seems to be a candidate for the observed problem.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
Andrew Banman
|
5f0f2887f4 |
mm/memory_hotplug.c: check for missing sections in test_pages_in_a_zone()
test_pages_in_a_zone() does not account for the possibility of missing sections in the given pfn range. pfn_valid_within always returns 1 when CONFIG_HOLES_IN_ZONE is not set, allowing invalid pfns from missing sections to pass the test, leading to a kernel oops. Wrap an additional pfn loop with PAGES_PER_SECTION granularity to check for missing sections before proceeding into the zone-check code. This also prevents a crash from offlining memory devices with missing sections. Despite this, it may be a good idea to keep the related patch '[PATCH 3/3] drivers: memory: prohibit offlining of memory blocks with missing sections' because missing sections in a memory block may lead to other problems not covered by the scope of this fix. Signed-off-by: Andrew Banman <abanman@sgi.com> Acked-by: Alex Thorlton <athorlton@sgi.com> Cc: Russ Anderson <rja@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Greg KH <greg@kroah.com> Cc: Seth Jennings <sjennings@variantweb.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Vladimir Davydov
|
6df38689e0 |
mm: memcontrol: fix possible memcg leak due to interrupted reclaim
Memory cgroup reclaim can be interrupted with mem_cgroup_iter_break()
once enough pages have been reclaimed, in which case, in contrast to a
full round-trip over a cgroup sub-tree, the current position stored in
mem_cgroup_reclaim_iter of the target cgroup does not get invalidated
and so is left holding the reference to the last scanned cgroup. If the
target cgroup does not get scanned again (we might have just reclaimed
the last page or all processes might exit and free their memory
voluntary), we will leak it, because there is nobody to put the
reference held by the iterator.
The problem is easy to reproduce by running the following command
sequence in a loop:
mkdir /sys/fs/cgroup/memory/test
echo 100M > /sys/fs/cgroup/memory/test/memory.limit_in_bytes
echo $$ > /sys/fs/cgroup/memory/test/cgroup.procs
memhog 150M
echo $$ > /sys/fs/cgroup/memory/cgroup.procs
rmdir test
The cgroups generated by it will never get freed.
This patch fixes this issue by making mem_cgroup_iter avoid taking
reference to the current position. In order not to hit use-after-free
bug while running reclaim in parallel with cgroup deletion, we make use
of ->css_released cgroup callback to clear references to the dying
cgroup in all reclaim iterators that might refer to it. This callback
is called right before scheduling rcu work which will free css, so if we
access iter->position from rcu read section, we might be sure it won't
go away under us.
[hannes@cmpxchg.org: clean up css ref handling]
Fixes:
|
||
|
Dan Streetman
|
8bc8b228d0 |
mm/zswap: change incorrect strncmp use to strcmp
Change the use of strncmp in zswap_pool_find_get() to strcmp. The use of strncmp is no longer correct, now that zswap_zpool_type is not an array; sizeof() will return the size of a pointer, which isn't the right length to compare. We don't need to use strncmp anyway, because the existing params and the passed in params are all guaranteed to be null terminated, so strcmp should be used. Signed-off-by: Dan Streetman <ddstreet@ieee.org> Reported-by: Weijie Yang <weijie.yang@samsung.com> Cc: Seth Jennings <sjennings@variantweb.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Chen Jie
|
a2b829d959 |
mm/oom_kill.c: avoid attempting to kill init sharing same memory
It's possible that an oom killed victim shares an ->mm with the init process and thus oom_kill_process() would end up trying to kill init as well. This has been shown in practice: Out of memory: Kill process 9134 (init) score 3 or sacrifice child Killed process 9134 (init) total-vm:1868kB, anon-rss:84kB, file-rss:572kB Kill process 1 (init) sharing same memory ... Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 And this will result in a kernel panic. If a process is forked by init and selected for oom kill while still sharing init_mm, then it's likely this system is in a recoverable state. However, it's better not to try to kill init and allow the machine to panic due to unkillable processes. [rientjes@google.com: rewrote changelog] [akpm@linux-foundation.org: fix inverted test, per Ben] Signed-off-by: Chen Jie <chenjie6@huawei.com> Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Li Zefan <lizefan@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Hugh Dickins
|
267a4c76bb |
tmpfs: fix shmem_evict_inode() warnings on i_blocks
Dmitry Vyukov provides a little program, autogenerated by syzkaller,
which races a fault on a mapping of a sparse memfd object, against
truncation of that object below the fault address: run repeatedly for a
few minutes, it reliably generates shmem_evict_inode()'s
WARN_ON(inode->i_blocks).
(But there's nothing specific to memfd here, nor to the fstat which it
happened to use to generate the fault: though that looked suspicious,
since a shmem_recalc_inode() had been added there recently. The same
problem can be reproduced with open+unlink in place of memfd_create, and
with fstatfs in place of fstat.)
v3.7 commit
|
||
|
Mike Kravetz
|
dbe409e4f5 |
mm/hugetlb.c: fix resv map memory leak for placeholder entries
Dmitry Vyukov reported the following memory leak
unreferenced object 0xffff88002eaafd88 (size 32):
comm "a.out", pid 5063, jiffies 4295774645 (age 15.810s)
hex dump (first 32 bytes):
28 e9 4e 63 00 88 ff ff 28 e9 4e 63 00 88 ff ff (.Nc....(.Nc....
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
kmalloc include/linux/slab.h:458
region_chg+0x2d4/0x6b0 mm/hugetlb.c:398
__vma_reservation_common+0x2c3/0x390 mm/hugetlb.c:1791
vma_needs_reservation mm/hugetlb.c:1813
alloc_huge_page+0x19e/0xc70 mm/hugetlb.c:1845
hugetlb_no_page mm/hugetlb.c:3543
hugetlb_fault+0x7a1/0x1250 mm/hugetlb.c:3717
follow_hugetlb_page+0x339/0xc70 mm/hugetlb.c:3880
__get_user_pages+0x542/0xf30 mm/gup.c:497
populate_vma_page_range+0xde/0x110 mm/gup.c:919
__mm_populate+0x1c7/0x310 mm/gup.c:969
do_mlock+0x291/0x360 mm/mlock.c:637
SYSC_mlock2 mm/mlock.c:658
SyS_mlock2+0x4b/0x70 mm/mlock.c:648
Dmitry identified a potential memory leak in the routine region_chg,
where a region descriptor is not free'ed on an error path.
However, the root cause for the above memory leak resides in region_del.
In this specific case, a "placeholder" entry is created in region_chg.
The associated page allocation fails, and the placeholder entry is left
in the reserve map. This is "by design" as the entry should be deleted
when the map is released. The bug is in the region_del routine which is
used to delete entries within a specific range (and when the map is
released). region_del did not handle the case where a placeholder entry
exactly matched the start of the range range to be deleted. In this
case, the entry would not be deleted and leaked. The fix is to take
these special placeholder entries into account in region_del.
The region_chg error path leak is also fixed.
Fixes:
|
||
|
Naoya Horiguchi
|
0d777df5d8 |
mm: hugetlb: call huge_pte_alloc() only if ptep is null
Currently at the beginning of hugetlb_fault(), we call huge_pte_offset()
and check whether the obtained *ptep is a migration/hwpoison entry or
not. And if not, then we get to call huge_pte_alloc(). This is racy
because the *ptep could turn into migration/hwpoison entry after the
huge_pte_offset() check. This race results in BUG_ON in
huge_pte_alloc().
We don't have to call huge_pte_alloc() when the huge_pte_offset()
returns non-NULL, so let's fix this bug with moving the code into else
block.
Note that the *ptep could turn into a migration/hwpoison entry after
this block, but that's not a problem because we have another
!pte_present check later (we never go into hugetlb_no_page() in that
case.)
Fixes:
|
||
|
Hugh Dickins
|
25be6a6595 |
mm: fix kerneldoc on mem_cgroup_replace_page
Whoops, I missed removing the kerneldoc comment of the lrucare arg removed from mem_cgroup_replace_page; but it's a good comment, keep it. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Michal Hocko
|
373ccbe592 |
mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress
Tetsuo Handa has reported that the system might basically livelock in
OOM condition without triggering the OOM killer.
The issue is caused by internal dependency of the direct reclaim on
vmstat counter updates (via zone_reclaimable) which are performed from
the workqueue context. If all the current workers get assigned to an
allocation request, though, they will be looping inside the allocator
trying to reclaim memory but zone_reclaimable can see stalled numbers so
it will consider a zone reclaimable even though it has been scanned way
too much. WQ concurrency logic will not consider this situation as a
congested workqueue because it relies that worker would have to sleep in
such a situation. This also means that it doesn't try to spawn new
workers or invoke the rescuer thread if the one is assigned to the
queue.
In order to fix this issue we need to do two things. First we have to
let wq concurrency code know that we are in trouble so we have to do a
short sleep. In order to prevent from issues handled by
|
||
|
Vlastimil Babka
|
475a2f905d |
mm: fix swapped Movable and Reclaimable in /proc/pagetypeinfo
Commit |
||
|
Vladimir Davydov
|
9516a18a9a |
memcg: fix memory.high target
When the memory.high threshold is exceeded, try_charge() schedules a task_work to reclaim the excess. The reclaim target is set to the number of pages requested by try_charge(). This is wrong, because try_charge() usually charges more pages than requested (batch > nr_pages) in order to refill per cpu stocks. As a result, a process in a cgroup can easily exceed memory.high significantly when doing a lot of charges w/o returning to userspace (e.g. reading a file in big chunks). Fix this issue by assuring that when exceeding memory.high a process reclaims as many pages as were actually charged (i.e. batch). Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Naoya Horiguchi
|
a88c769548 |
mm: hugetlb: fix hugepage memory leak caused by wrong reserve count
When dequeue_huge_page_vma() in alloc_huge_page() fails, we fall back on alloc_buddy_huge_page() to directly create a hugepage from the buddy allocator. In that case, however, if alloc_buddy_huge_page() succeeds we don't decrement h->resv_huge_pages, which means that successful hugetlb_fault() returns without releasing the reserve count. As a result, subsequent hugetlb_fault() might fail despite that there are still free hugepages. This patch simply adds decrementing code on that code path. I reproduced this problem when testing v4.3 kernel in the following situation: - the test machine/VM is a NUMA system, - hugepage overcommiting is enabled, - most of hugepages are allocated and there's only one free hugepage which is on node 0 (for example), - another program, which calls set_mempolicy(MPOL_BIND) to bind itself to node 1, tries to allocate a hugepage, - the allocation should fail but the reserve count is still hold. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: David Rientjes <rientjes@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: <stable@vger.kernel.org> [3.16+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Linus Torvalds
|
5406812e59 |
Merge branch 'for-4.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
"More change than I'd have liked at this stage. The pids controller
and the changes made to cgroup core to support it introduced and
revealed several important issues.
- Assigning membership to a newly created task and migrating it can
race leading to incorrect accounting. Oleg fixed it by widening
threadgroup synchronization. It looks like we'll be able to merge
it with a different percpu rwsem which is used in fork path making
things simpler and cheaper.
- The recent change to extend cgroup membership to zombies (so that
pid accounting can extend till the pid is actually released) missed
pinning the underlying data structures leading to use-after-free.
Fixed.
- v2 hierarchy was calling subsystem callbacks with the wrong target
cgroup_subsys_state based on the incorrect assumption that they
share the same target. pids is the first controller affected by
this. Subsys callbacks updated so that they can deal with
multi-target migrations"
* 'for-4.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup_pids: don't account for the root cgroup
cgroup: fix handling of multi-destination migration from subtree_control enabling
cgroup_freezer: simplify propagation of CGROUP_FROZEN clearing in freezer_attach()
cgroup: pids: kill pids_fork(), simplify pids_can_fork() and pids_cancel_fork()
cgroup: pids: fix race between cgroup_post_fork() and cgroup_migrate()
cgroup: make css_set pin its css's to avoid use-afer-free
cgroup: fix cftype->file_offset handling
|
||
|
Tejun Heo
|
0b98f0c042 |
Merge branch 'master' into for-4.4-fixes
The following commit which went into mainline through networking tree |
||
|
Tejun Heo
|
1f7dd3e5a6 |
cgroup: fix handling of multi-destination migration from subtree_control enabling
Consider the following v2 hierarchy.
P0 (+memory) --- P1 (-memory) --- A
\- B
P0 has memory enabled in its subtree_control while P1 doesn't. If
both A and B contain processes, they would belong to the memory css of
P1. Now if memory is enabled on P1's subtree_control, memory csses
should be created on both A and B and A's processes should be moved to
the former and B's processes the latter. IOW, enabling controllers
can cause atomic migrations into different csses.
The core cgroup migration logic has been updated accordingly but the
controller migration methods haven't and still assume that all tasks
migrate to a single target css; furthermore, the methods were fed the
css in which subtree_control was updated which is the parent of the
target csses. pids controller depends on the migration methods to
move charges and this made the controller attribute charges to the
wrong csses often triggering the following warning by driving a
counter negative.
WARNING: CPU: 1 PID: 1 at kernel/cgroup_pids.c:97 pids_cancel.constprop.6+0x31/0x40()
Modules linked in:
CPU: 1 PID: 1 Comm: systemd Not tainted 4.4.0-rc1+ #29
...
ffffffff81f65382 ffff88007c043b90 ffffffff81551ffc 0000000000000000
ffff88007c043bc8 ffffffff810de202 ffff88007a752000 ffff88007a29ab00
ffff88007c043c80 ffff88007a1d8400 0000000000000001 ffff88007c043bd8
Call Trace:
[<ffffffff81551ffc>] dump_stack+0x4e/0x82
[<ffffffff810de202>] warn_slowpath_common+0x82/0xc0
[<ffffffff810de2fa>] warn_slowpath_null+0x1a/0x20
[<ffffffff8118e031>] pids_cancel.constprop.6+0x31/0x40
[<ffffffff8118e0fd>] pids_can_attach+0x6d/0xf0
[<ffffffff81188a4c>] cgroup_taskset_migrate+0x6c/0x330
[<ffffffff81188e05>] cgroup_migrate+0xf5/0x190
[<ffffffff81189016>] cgroup_attach_task+0x176/0x200
[<ffffffff8118949d>] __cgroup_procs_write+0x2ad/0x460
[<ffffffff81189684>] cgroup_procs_write+0x14/0x20
[<ffffffff811854e5>] cgroup_file_write+0x35/0x1c0
[<ffffffff812e26f1>] kernfs_fop_write+0x141/0x190
[<ffffffff81265f88>] __vfs_write+0x28/0xe0
[<ffffffff812666fc>] vfs_write+0xac/0x1a0
[<ffffffff81267019>] SyS_write+0x49/0xb0
[<ffffffff81bcef32>] entry_SYSCALL_64_fastpath+0x12/0x76
This patch fixes the bug by removing @css parameter from the three
migration methods, ->can_attach, ->cancel_attach() and ->attach() and
updating cgroup_taskset iteration helpers also return the destination
css in addition to the task being migrated. All controllers are
updated accordingly.
* Controllers which don't care whether there are one or multiple
target csses can be converted trivially. cpu, io, freezer, perf,
netclassid and netprio fall in this category.
* cpuset's current implementation assumes that there's single source
and destination and thus doesn't support v2 hierarchy already. The
only change made by this patchset is how that single destination css
is obtained.
* memory migration path already doesn't do anything on v2. How the
single destination css is obtained is updated and the prep stage of
mem_cgroup_can_attach() is reordered to accomodate the change.
* pids is the only controller which was affected by this bug. It now
correctly handles multi-destination migrations and no longer causes
counter underflow from incorrect accounting.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Cc: Aleksa Sarai <cyphar@cyphar.com>
|
||
|
Peter Zijlstra
|
90eec103b9 |
treewide: Remove old email address
There were still a number of references to my old Red Hat email address in the kernel source. Remove these while keeping the Red Hat copyright notices intact. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
|
Linus Torvalds
|
104e2a6f8b |
Merge branch 'akpm' (patches from Andrew)
Merge slub bulk allocator updates from Andrew Morton:
"This missed the merge window because I was waiting for some repairs to
come in. Nothing actually uses the bulk allocator yet and the changes
to other code paths are pretty small. And the net guys are waiting
for this so they can start merging the client code"
More comments from Jesper Dangaard Brouer:
"The kmem_cache_alloc_bulk() call, in mm/slub.c, were included in
previous kernel. The present version contains a bug. Vladimir
Davydov noticed it contained a bug, when kernel is compiled with
CONFIG_MEMCG_KMEM (see commit 03ec0ed57ffc: "slub: fix kmem cgroup
bug in kmem_cache_alloc_bulk"). Plus the mem cgroup counterpart in
kmem_cache_free_bulk() were missing (see commit
|
||
|
Jesper Dangaard Brouer
|
865762a811 |
slab/slub: adjust kmem_cache_alloc_bulk API
Adjust kmem_cache_alloc_bulk API before we have any real users. Adjust API to return type 'int' instead of previously type 'bool'. This is done to allow future extension of the bulk alloc API. A future extension could be to allow SLUB to stop at a page boundary, when specified by a flag, and then return the number of objects. The advantage of this approach, would make it easier to make bulk alloc run without local IRQs disabled. With an approach of cmpxchg "stealing" the entire c->freelist or page->freelist. To avoid overshooting we would stop processing at a slab-page boundary. Else we always end up returning some objects at the cost of another cmpxchg. To keep compatible with future users of this API linking against an older kernel when using the new flag, we need to return the number of allocated objects with this API change. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Jesper Dangaard Brouer
|
033745189b |
slub: add missing kmem cgroup support to kmem_cache_free_bulk
Initial implementation missed support for kmem cgroup support in kmem_cache_free_bulk() call, add this. If CONFIG_MEMCG_KMEM is not enabled, the compiler should be smart enough to not add any asm code. Incoming bulk free objects can belong to different kmem cgroups, and object free call can happen at a later point outside memcg context. Thus, we need to keep the orig kmem_cache, to correctly verify if a memcg object match against its "root_cache" (s->memcg_params.root_cache). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Jesper Dangaard Brouer
|
03ec0ed57f |
slub: fix kmem cgroup bug in kmem_cache_alloc_bulk
The call slab_pre_alloc_hook() interacts with kmemgc and is not allowed to be called several times inside the bulk alloc for loop, due to the call to memcg_kmem_get_cache(). This would result in hitting the VM_BUG_ON in __memcg_kmem_get_cache. As suggested by Vladimir Davydov, change slab_post_alloc_hook() to be able to handle an array of objects. A subtle detail is, loop iterator "i" in slab_post_alloc_hook() must have same type (size_t) as size argument. This helps the compiler to easier realize that it can remove the loop, when all debug statements inside loop evaluates to nothing. Note, this is only an issue because the kernel is compiled with GCC option: -fno-strict-overflow In slab_alloc_node() the compiler inlines and optimizes the invocation of slab_post_alloc_hook(s, flags, 1, &object) by removing the loop and access object directly. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Reported-by: Vladimir Davydov <vdavydov@virtuozzo.com> Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Jesper Dangaard Brouer
|
d0ecd894e3 |
slub: optimize bulk slowpath free by detached freelist
This change focus on improving the speed of object freeing in the
"slowpath" of kmem_cache_free_bulk.
The calls slab_free (fastpath) and __slab_free (slowpath) have been
extended with support for bulk free, which amortize the overhead of
the (locked) cmpxchg_double.
To use the new bulking feature, we build what I call a detached
freelist. The detached freelist takes advantage of three properties:
1) the free function call owns the object that is about to be freed,
thus writing into this memory is synchronization-free.
2) many freelist's can co-exist side-by-side in the same slab-page
each with a separate head pointer.
3) it is the visibility of the head pointer that needs synchronization.
Given these properties, the brilliant part is that the detached
freelist can be constructed without any need for synchronization. The
freelist is constructed directly in the page objects, without any
synchronization needed. The detached freelist is allocated on the
stack of the function call kmem_cache_free_bulk. Thus, the freelist
head pointer is not visible to other CPUs.
All objects in a SLUB freelist must belong to the same slab-page.
Thus, constructing the detached freelist is about matching objects
that belong to the same slab-page. The bulk free array is scanned is
a progressive manor with a limited look-ahead facility.
Kmem debug support is handled in call of slab_free().
Notice kmem_cache_free_bulk no longer need to disable IRQs. This
only slowed down single free bulk with approx 3 cycles.
Performance data:
Benchmarked[1] obj size 256 bytes on CPU i7-4790K @ 4.00GHz
SLUB fastpath single object quick reuse: 47 cycles(tsc) 11.931 ns
To get stable and comparable numbers, the kernel have been booted with
"slab_merge" (this also improve performance for larger bulk sizes).
Performance data, compared against fallback bulking:
bulk - fallback bulk - improvement with this patch
1 - 62 cycles(tsc) 15.662 ns - 49 cycles(tsc) 12.407 ns- improved 21.0%
2 - 55 cycles(tsc) 13.935 ns - 30 cycles(tsc) 7.506 ns - improved 45.5%
3 - 53 cycles(tsc) 13.341 ns - 23 cycles(tsc) 5.865 ns - improved 56.6%
4 - 52 cycles(tsc) 13.081 ns - 20 cycles(tsc) 5.048 ns - improved 61.5%
8 - 50 cycles(tsc) 12.627 ns - 18 cycles(tsc) 4.659 ns - improved 64.0%
16 - 49 cycles(tsc) 12.412 ns - 17 cycles(tsc) 4.495 ns - improved 65.3%
30 - 49 cycles(tsc) 12.484 ns - 18 cycles(tsc) 4.533 ns - improved 63.3%
32 - 50 cycles(tsc) 12.627 ns - 18 cycles(tsc) 4.707 ns - improved 64.0%
34 - 96 cycles(tsc) 24.243 ns - 23 cycles(tsc) 5.976 ns - improved 76.0%
48 - 83 cycles(tsc) 20.818 ns - 21 cycles(tsc) 5.329 ns - improved 74.7%
64 - 74 cycles(tsc) 18.700 ns - 20 cycles(tsc) 5.127 ns - improved 73.0%
128 - 90 cycles(tsc) 22.734 ns - 27 cycles(tsc) 6.833 ns - improved 70.0%
158 - 99 cycles(tsc) 24.776 ns - 30 cycles(tsc) 7.583 ns - improved 69.7%
250 - 104 cycles(tsc) 26.089 ns - 37 cycles(tsc) 9.280 ns - improved 64.4%
Performance data, compared current in-kernel bulking:
bulk - curr in-kernel - improvement with this patch
1 - 46 cycles(tsc) - 49 cycles(tsc) - improved (cycles:-3) -6.5%
2 - 27 cycles(tsc) - 30 cycles(tsc) - improved (cycles:-3) -11.1%
3 - 21 cycles(tsc) - 23 cycles(tsc) - improved (cycles:-2) -9.5%
4 - 18 cycles(tsc) - 20 cycles(tsc) - improved (cycles:-2) -11.1%
8 - 17 cycles(tsc) - 18 cycles(tsc) - improved (cycles:-1) -5.9%
16 - 18 cycles(tsc) - 17 cycles(tsc) - improved (cycles: 1) 5.6%
30 - 18 cycles(tsc) - 18 cycles(tsc) - improved (cycles: 0) 0.0%
32 - 18 cycles(tsc) - 18 cycles(tsc) - improved (cycles: 0) 0.0%
34 - 78 cycles(tsc) - 23 cycles(tsc) - improved (cycles:55) 70.5%
48 - 60 cycles(tsc) - 21 cycles(tsc) - improved (cycles:39) 65.0%
64 - 49 cycles(tsc) - 20 cycles(tsc) - improved (cycles:29) 59.2%
128 - 69 cycles(tsc) - 27 cycles(tsc) - improved (cycles:42) 60.9%
158 - 79 cycles(tsc) - 30 cycles(tsc) - improved (cycles:49) 62.0%
250 - 86 cycles(tsc) - 37 cycles(tsc) - improved (cycles:49) 57.0%
Performance with normal SLUB merging is significantly slower for
larger bulking. This is believed to (primarily) be an effect of not
having to share the per-CPU data-structures, as tuning per-CPU size
can achieve similar performance.
bulk - slab_nomerge - normal SLUB merge
1 - 49 cycles(tsc) - 49 cycles(tsc) - merge slower with cycles:0
2 - 30 cycles(tsc) - 30 cycles(tsc) - merge slower with cycles:0
3 - 23 cycles(tsc) - 23 cycles(tsc) - merge slower with cycles:0
4 - 20 cycles(tsc) - 20 cycles(tsc) - merge slower with cycles:0
8 - 18 cycles(tsc) - 18 cycles(tsc) - merge slower with cycles:0
16 - 17 cycles(tsc) - 17 cycles(tsc) - merge slower with cycles:0
30 - 18 cycles(tsc) - 23 cycles(tsc) - merge slower with cycles:5
32 - 18 cycles(tsc) - 22 cycles(tsc) - merge slower with cycles:4
34 - 23 cycles(tsc) - 22 cycles(tsc) - merge slower with cycles:-1
48 - 21 cycles(tsc) - 22 cycles(tsc) - merge slower with cycles:1
64 - 20 cycles(tsc) - 48 cycles(tsc) - merge slower with cycles:28
128 - 27 cycles(tsc) - 57 cycles(tsc) - merge slower with cycles:30
158 - 30 cycles(tsc) - 59 cycles(tsc) - merge slower with cycles:29
250 - 37 cycles(tsc) - 56 cycles(tsc) - merge slower with cycles:19
Joint work with Alexander Duyck.
[1] https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/mm/slab_bulk_test01.c
[akpm@linux-foundation.org: BUG_ON -> WARN_ON;return]
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
Jesper Dangaard Brouer
|
81084651d7 |
slub: support for bulk free with SLUB freelists
Make it possible to free a freelist with several objects by adjusting API of slab_free() and __slab_free() to have head, tail and an objects counter (cnt). Tail being NULL indicate single object free of head object. This allow compiler inline constant propagation in slab_free() and slab_free_freelist_hook() to avoid adding any overhead in case of single object free. This allows a freelist with several objects (all within the same slab-page) to be free'ed using a single locked cmpxchg_double in __slab_free() and with an unlocked cmpxchg_double in slab_free(). Object debugging on the free path is also extended to handle these freelists. When CONFIG_SLUB_DEBUG is enabled it will also detect if objects don't belong to the same slab-page. These changes are needed for the next patch to bulk free the detached freelists it introduces and constructs. Micro benchmarking showed no performance reduction due to this change, when debugging is turned off (compiled with CONFIG_SLUB_DEBUG). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Linus Torvalds
|
3ad5d7e06a |
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton: "A bunch of fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: slub: mark the dangling ifdef #else of CONFIG_SLUB_DEBUG slub: avoid irqoff/on in bulk allocation slub: create new ___slab_alloc function that can be called with irqs disabled mm: fix up sparse warning in gfpflags_allow_blocking ocfs2: fix umask ignored issue PM/OPP: add entry in MAINTAINERS kernel/panic.c: turn off locks debug before releasing console lock kernel/signal.c: unexport sigsuspend() kasan: fix kmemleak false-positive in kasan_module_alloc() fat: fix fake_offset handling on error path mm/hugetlbfs: fix bugs in fallocate hole punch of areas with holes mm/page-writeback.c: initialize m_dirty to avoid compile warning various: fix pci_set_dma_mask return value checking mm: loosen MADV_NOHUGEPAGE to enable Qemu postcopy on s390 mm: vmalloc: don't remove inexistent guard hole in remove_vm_area() tools/vm/page-types.c: support KPF_IDLE ncpfs: don't allow negative timeouts configfs: allow dynamic group creation MAINTAINERS: add Moritz as reviewer for FPGA Manager Framework slab.h: sprinkle __assume_aligned attributes |
||
|
Jesper Dangaard Brouer
|
b4a6471879 |
slub: mark the dangling ifdef #else of CONFIG_SLUB_DEBUG
The #ifdef of CONFIG_SLUB_DEBUG is located very far from the associated #else. For readability mark it with a comment. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Christoph Lameter
|
87098373e2 |
slub: avoid irqoff/on in bulk allocation
Use the new function that can do allocation while interrupts are disabled. Avoids irq on/off sequences. Signed-off-by: Christoph Lameter <cl@linux.com> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |