task_struct->memcg_kmem_skip_account was initially introduced to avoid
recursion during kmem cache creation: memcg_kmem_get_cache, which is
called by kmem_cache_alloc to determine the per-memcg cache to account
allocation to, may issue lazy cache creation if the needed cache doesn't
exist, which means issuing yet another kmem_cache_alloc. We can't just
pass a flag to the nested kmem_cache_alloc disabling kmem accounting,
because there are hidden allocations, e.g. in INIT_WORK. So we
introduced a flag on the task_struct, memcg_kmem_skip_account, making
memcg_kmem_get_cache return immediately.
By its nature, the flag may also be used to disable accounting for
allocations shared among different cgroups, and currently it is used this
way in memcg_activate_kmem. Using it like this looks like abusing it to
me. If we want to disable accounting for some allocations (which we will
definitely want one day), we should either add GFP_NO_MEMCG or GFP_MEMCG
flag in order to blacklist/whitelist some allocations.
For now, let's simply remove memcg_stop/resume_kmem_account from
memcg_activate_kmem.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The alignment in cma_alloc() was done w.r.t. the bitmap. This is a
problem when, for example:
- a device requires 16M (order 12) alignment
- the CMA region is not 16 M aligned
In such a case, can result with the CMA region starting at, say,
0x2f800000 but any allocation you make from there will be aligned from
there. Requesting an allocation of 32 M with 16 M alignment will result
in an allocation from 0x2f800000 to 0x31800000, which doesn't work very
well if your strange device requires 16M alignment.
Change to use bitmap_find_next_zero_area_off() to account for the
difference in alignment at reserve-time and alloc-time.
Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both register and unregister call build_map_info() in order to create the
list of mappings before installing or removing breakpoints for every mm
which maps file backed memory. As such, there is no reason to hold the
i_mmap_rwsem exclusively, so share it and allow concurrent readers to
build the mapping data.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The i_mmap_mutex is a close cousin of the anon vma lock, both protecting
similar data, one for file backed pages and the other for anon memory. To
this end, this lock can also be a rwsem. In addition, there are some
important opportunities to share the lock when there are no tree
modifications.
This conversion is straightforward. For now, all users take the write
lock.
[sfr@canb.auug.org.au: update fremap.c]
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This series is a continuation of the conversion of the i_mmap_mutex to
rwsem, following what we have for the anon memory counterpart. With
Hugh's feedback from the first iteration.
Ultimately, the most obvious paths that require exclusive ownership of the
lock is when we modify the VMA interval tree, via
vma_interval_tree_insert() and vma_interval_tree_remove() families. Cases
such as unmapping, where the ptes content is changed but the tree remains
untouched should make it safe to share the i_mmap_rwsem.
As such, the code of course is straightforward, however the devil is very
much in the details. While its been tested on a number of workloads
without anything exploding, I would not be surprised if there are some
less documented/known assumptions about the lock that could suffer from
these changes. Or maybe I'm just missing something, but either way I
believe its at the point where it could use more eyes and hopefully some
time in linux-next.
Because the lock type conversion is the heart of this patchset,
its worth noting a few comparisons between mutex vs rwsem (xadd):
(i) Same size, no extra footprint.
(ii) Both have CONFIG_XXX_SPIN_ON_OWNER capabilities for
exclusive lock ownership.
(iii) Both can be slightly unfair wrt exclusive ownership, with
writer lock stealing properties, not necessarily respecting
FIFO order for granting the lock when contended.
(iv) Mutexes can be slightly faster than rwsems when
the lock is non-contended.
(v) Both suck at performance for debug (slowpaths), which
shouldn't matter anyway.
Sharing the lock is obviously beneficial, and sem writer ownership is
close enough to mutexes. The biggest winner of these changes is
migration.
As for concrete numbers, the following performance results are for a
4-socket 60-core IvyBridge-EX with 130Gb of RAM.
Both alltests and disk (xfs+ramdisk) workloads of aim7 suite do quite well
with this set, with a steady ~60% throughput (jpm) increase for alltests
and up to ~30% for disk for high amounts of concurrency. Lower counts of
workload users (< 100) does not show much difference at all, so at least
no regressions.
3.18-rc1 3.18-rc1-i_mmap_rwsem
alltests-100 17918.72 ( 0.00%) 28417.97 ( 58.59%)
alltests-200 16529.39 ( 0.00%) 26807.92 ( 62.18%)
alltests-300 16591.17 ( 0.00%) 26878.08 ( 62.00%)
alltests-400 16490.37 ( 0.00%) 26664.63 ( 61.70%)
alltests-500 16593.17 ( 0.00%) 26433.72 ( 59.30%)
alltests-600 16508.56 ( 0.00%) 26409.20 ( 59.97%)
alltests-700 16508.19 ( 0.00%) 26298.58 ( 59.31%)
alltests-800 16437.58 ( 0.00%) 26433.02 ( 60.81%)
alltests-900 16418.35 ( 0.00%) 26241.61 ( 59.83%)
alltests-1000 16369.00 ( 0.00%) 26195.76 ( 60.03%)
alltests-1100 16330.11 ( 0.00%) 26133.46 ( 60.03%)
alltests-1200 16341.30 ( 0.00%) 26084.03 ( 59.62%)
alltests-1300 16304.75 ( 0.00%) 26024.74 ( 59.61%)
alltests-1400 16231.08 ( 0.00%) 25952.35 ( 59.89%)
alltests-1500 16168.06 ( 0.00%) 25850.58 ( 59.89%)
alltests-1600 16142.56 ( 0.00%) 25767.42 ( 59.62%)
alltests-1700 16118.91 ( 0.00%) 25689.58 ( 59.38%)
alltests-1800 16068.06 ( 0.00%) 25599.71 ( 59.32%)
alltests-1900 16046.94 ( 0.00%) 25525.92 ( 59.07%)
alltests-2000 16007.26 ( 0.00%) 25513.07 ( 59.38%)
disk-100 7582.14 ( 0.00%) 7257.48 ( -4.28%)
disk-200 6962.44 ( 0.00%) 7109.15 ( 2.11%)
disk-300 6435.93 ( 0.00%) 6904.75 ( 7.28%)
disk-400 6370.84 ( 0.00%) 6861.26 ( 7.70%)
disk-500 6353.42 ( 0.00%) 6846.71 ( 7.76%)
disk-600 6368.82 ( 0.00%) 6806.75 ( 6.88%)
disk-700 6331.37 ( 0.00%) 6796.01 ( 7.34%)
disk-800 6324.22 ( 0.00%) 6788.00 ( 7.33%)
disk-900 6253.52 ( 0.00%) 6750.43 ( 7.95%)
disk-1000 6242.53 ( 0.00%) 6855.11 ( 9.81%)
disk-1100 6234.75 ( 0.00%) 6858.47 ( 10.00%)
disk-1200 6312.76 ( 0.00%) 6845.13 ( 8.43%)
disk-1300 6309.95 ( 0.00%) 6834.51 ( 8.31%)
disk-1400 6171.76 ( 0.00%) 6787.09 ( 9.97%)
disk-1500 6139.81 ( 0.00%) 6761.09 ( 10.12%)
disk-1600 4807.12 ( 0.00%) 6725.33 ( 39.90%)
disk-1700 4669.50 ( 0.00%) 5985.38 ( 28.18%)
disk-1800 4663.51 ( 0.00%) 5972.99 ( 28.08%)
disk-1900 4674.31 ( 0.00%) 5949.94 ( 27.29%)
disk-2000 4668.36 ( 0.00%) 5834.93 ( 24.99%)
In addition, a 67.5% increase in successfully migrated NUMA pages, thus
improving node locality.
The patch layout is simple but designed for bisection (in case reversion
is needed if the changes break upstream) and easier review:
o Patches 1-4 convert the i_mmap lock from mutex to rwsem.
o Patches 5-10 share the lock in specific paths, each patch
details the rationale behind why it should be safe.
This patchset has been tested with: postgres 9.4 (with brand new hugetlb
support), hugetlbfs test suite (all tests pass, in fact more tests pass
with these changes than with an upstream kernel), ltp, aim7 benchmarks,
memcached and iozone with the -B option for mmap'ing. *Untested* paths
are nommu, memory-failure, uprobes and xip.
This patch (of 8):
Various parts of the kernel acquire and release this mutex, so add
i_mmap_lock_write() and immap_unlock_write() helper functions that will
encapsulate this logic. The next patch will make use of these.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7654e9d4fd ("drivers/rtc/rtc-snvs: fix suspend/resume")
replaces SIMPLE_DEV_PM_OPS with direct declaration of snvs_rtc_pm_ops,
but does so outside #ifdef CONFIG_PM_SLEEP. This causes the driver
build to fail if CONFIG_PM_SLEEP is not configured.
Fixes: 7654e9d4fd ("drivers/rtc/rtc-snvs: fix suspend/resume")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Sanchayan Maity <maitysanchayan@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull pstore update #2 from Tony Luck:
"Couple of pstore-ram enhancements to allow use of different memory
attributes"
* tag 'please-pull-morepstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
pstore-ram: Allow optional mapping with pgprot_noncached
pstore-ram: Fix hangs by using write-combine mappings
Pull btrfs update from Chris Mason:
"From a feature point of view, most of the code here comes from Miao
Xie and others at Fujitsu to implement scrubbing and replacing devices
on raid56. This has been in development for a while, and it's a big
improvement.
Filipe and Josef have a great assortment of fixes, many of which solve
problems corruptions either after a crash or in error conditions. I
still have a round two from Filipe for next week that solves
corruptions with discard and block group removal"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (62 commits)
Btrfs: make get_caching_control unconditionally return the ctl
Btrfs: fix unprotected deletion from pending_chunks list
Btrfs: fix fs mapping extent map leak
Btrfs: fix memory leak after block remove + trimming
Btrfs: make btrfs_abort_transaction consider existence of new block groups
Btrfs: fix race between writing free space cache and trimming
Btrfs: fix race between fs trimming and block group remove/allocation
Btrfs, replace: enable dev-replace for raid56
Btrfs: fix freeing used extents after removing empty block group
Btrfs: fix crash caused by block group removal
Btrfs: fix invalid block group rbtree access after bg is removed
Btrfs, raid56: fix use-after-free problem in the final device replace procedure on raid56
Btrfs, replace: write raid56 parity into the replace target device
Btrfs, replace: write dirty pages into the replace target device
Btrfs, raid56: support parity scrub on raid56
Btrfs, raid56: use a variant to record the operation type
Btrfs, scrub: repair the common data on RAID5/6 if it is corrupted
Btrfs, raid56: don't change bbio and raid_map
Btrfs: remove unnecessary code of stripe_index assignment in __btrfs_map_block
Btrfs: remove noused bbio_ret in __btrfs_map_block in condition
...
Pull HID updates from Jiri Kosina:
- i2c-hid race condition fix from Jean-Baptiste Maneyrol
- Logitech driver now supports vendor-specific HID++ protocol, allowing
us to deliver a full multitouch support on wider range of Logitech
touchpads. Written by Benjamin Tissoires
- MS Surface Pro 3 Type Cover support added by Alan Wu
- RMI touchpad support improvements from Andrew Duggan
- a lot of updates to Wacom driver from Jason Gerecke and Ping Cheng
- various small fixes all over the place
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (56 commits)
HID: rmi: The address of query8 must be calculated based on which query registers are present
HID: rmi: Check for additional ACM registers appended to F11 data report
HID: i2c-hid: prevent buffer overflow in early IRQ
HID: logitech-hidpp: disable io in probe error path
HID: logitech-hidpp: add boundary check for name retrieval
HID: logitech-hidpp: check name retrieval return code
HID: logitech-hidpp: do not return the name length
HID: wacom: Report input events for each finger on generic devices
HID: wacom: Initialize MT slots for generic devices at post_parse_hid
HID: wacom: Update maximum X/Y accounding to outbound offset
HID: wacom: Add support for DTU-1031X
HID: wacom: add defines for new Cintiq and DTU outbound tracking
HID: wacom: fix freeze on open when autosuspend is on
HID: wacom: re-add accidentally dropped Lenovo PID
HID: make hid_report_len as a static inline function in hid.h
HID: wacom: Consult the application usage when determining field type
HID: wacom: PAD is independent with pen/touch
HID: multitouch: Add quirk for VTL touch panels
HID: i2c-hid: fix race condition reading reports
HID: wacom: Add angular resolution data to some ABS axes
...
Pull UBI/UBIFS updates from Artem Bityutskiy:
"This includes the following UBI/UBIFS changes:
- UBI debug messages now include the UBI device number. This change
is responsible for the big diffstat since it touched every
debugging print statement.
- An Xattr bug-fix which fixes SELinux support
- Several error path fixes in UBI/UBIFS"
* tag 'upstream-3.19-rc1' of git://git.infradead.org/linux-ubifs:
UBI: Fix invalid vfree()
UBI: Fix double free after do_sync_erase()
UBIFS: fix a couple bugs in UBIFS xattr length calculation
UBI: vtbl: Use ubi_eba_atomic_leb_change()
UBI: Extend UBI layer debug/messaging capabilities
UBIFS: fix budget leak in error path
Pull xfs update from Dave Chinner:
"There's relatively little change in this update; it is mainly bug
fixes, cleanups and more of the on-going libxfs restructuring and
on-disk format header consolidation work.
Details:
- more on-disk format header consolidation
- move some structures shared with userspace to libxfs
- new per-mount workqueue to fix for deadlocks between nested loop
mounted filesystems
- various bug fixes for ENOSPC, stats, quota off and preallocation
- a bunch of compiler warning fixes for set-but-unused variables
- various code cleanups"
* tag 'xfs-for-linus-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (24 commits)
xfs: split metadata and log buffer completion to separate workqueues
xfs: fix set-but-unused warnings
xfs: move type conversion functions to xfs_dir.h
xfs: move ftype conversion functions to libxfs
xfs: lobotomise xfs_trans_read_buf_map()
xfs: active inodes stat is broken
xfs: cleanup xfs_bmse_merge returns
xfs: cleanup xfs_bmse_shift_one goto mess
xfs: fix premature enospc on inode allocation
xfs: overflow in xfs_iomap_eof_align_last_fsb
xfs: fix simple_return.cocci warning in xfs_bmse_shift_one
xfs: fix simple_return.cocci warning in xfs_file_readdir
libxfs: fix simple_return.cocci warnings
xfs: remove unnecessary null checks
xfs: merge xfs_inum.h into xfs_format.h
xfs: move most of xfs_sb.h to xfs_format.h
xfs: merge xfs_ag.h into xfs_format.h
xfs: move acl structures to xfs_format.h
xfs: merge xfs_dinode.h into xfs_format.h
xfs: catch invalid negative blknos in _xfs_buf_find()
...
Pull ext4 updates from Ted Ts'o:
"Lots of bugs fixes, including Zheng and Jan's extent status shrinker
fixes, which should improve CPU utilization and potential soft lockups
under heavy memory pressure, and Eric Whitney's bigalloc fixes"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (26 commits)
ext4: ext4_da_convert_inline_data_to_extent drop locked page after error
ext4: fix suboptimal seek_{data,hole} extents traversial
ext4: ext4_inline_data_fiemap should respect callers argument
ext4: prevent fsreentrance deadlock for inline_data
ext4: forbid journal_async_commit in data=ordered mode
jbd2: remove unnecessary NULL check before iput()
ext4: Remove an unnecessary check for NULL before iput()
ext4: remove unneeded code in ext4_unlink
ext4: don't count external journal blocks as overhead
ext4: remove never taken branch from ext4_ext_shift_path_extents()
ext4: create nojournal_checksum mount option
ext4: update comments regarding ext4_delete_inode()
ext4: cleanup GFP flags inside resize path
ext4: introduce aging to extent status tree
ext4: cleanup flag definitions for extent status tree
ext4: limit number of scanned extents in status tree shrinker
ext4: move handling of list of shrinkable inodes into extent status code
ext4: change LRU to round-robin in extent status tree shrinker
ext4: cache extent hole in extent status tree for ext4_da_map_blocks()
ext4: fix block reservation for bigalloc filesystems
...
Tony Luck
Vladimir Davydov
Gregory Fong
Michal Nazarewicz
Davidlohr Bueso
Xiubo Li
Guenter Roeck
Linus Torvalds
Jiri Kosina