Since Linux 2.6.33 the kernel has support for real O_SYNC, which made
the osyncisosync option a no-op. Warn the users about this and remove
the mount flag for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Introduce a new truncate calling sequence into fs/mm subsystems. Rather than
setattr > vmtruncate > truncate, have filesystems call their truncate sequence
from ->setattr if filesystem specific operations are required. vmtruncate is
deprecated, and truncate_pagecache and inode_newsize_ok helpers introduced
previously should be used.
simple_setattr is introduced for simple in-ram filesystems to implement
the new truncate sequence. Eventually all filesystems should be converted
to implement a setattr, and the default code in notify_change should go
away.
simple_setsize is also introduced to perform just the ATTR_SIZE portion
of simple_setattr (ie. changing i_size and trimming pagecache).
To implement the new truncate sequence:
- filesystem specific manipulations (eg freeing blocks) must be done in
the setattr method rather than ->truncate.
- vmtruncate can not be used by core code to trim blocks past i_size in
the event of write failure after allocation, so this must be performed
in the fs code.
- convert usage of helpers block_write_begin, nobh_write_begin,
cont_write_begin, and *blockdev_direct_IO* to use _newtrunc postfixed
variants. These avoid calling vmtruncate to trim blocks (see previous).
- inode_setattr should not be used. generic_setattr is a new function
to be used to copy simple attributes into the generic inode.
- make use of the better opportunity to handle errors with the new sequence.
Big problem with the previous calling sequence: the filesystem is not called
until i_size has already changed. This means it is not allowed to fail the
call, and also it does not know what the previous i_size was. Also, generic
code calling vmtruncate to truncate allocated blocks in case of error had
no good way to return a meaningful error (or, for example, atomically handle
block deallocation).
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The inode's i_size is not protected by the big kernel lock. Therefore it
does not make sense to recommend taking the BKL in filesystems llseek
operations. Instead it should use the inode's mutex or use just use
i_size_read() instead. Add a note that this is not protecting
file->f_pos.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
squashfs: update documentation to include description of xattr layout
squashfs: fix name reading in squashfs_xattr_get
squashfs: constify xattr handlers
squashfs: xattr fix sparse warnings
squashfs: xattr_lookup sparse fix
squashfs: add xattr support configure option
squashfs: add new extended inode types
squashfs: add support for xattr reading
squashfs: add xattr id support
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
xfs: Ensure inode allocation buffers are fully replayed
xfs: enable background pushing of the CIL
xfs: forced unmounts need to push the CIL
xfs: Introduce delayed logging core code
xfs: Delayed logging design documentation
xfs: Improve scalability of busy extent tracking
xfs: make the log ticket ID available outside the log infrastructure
xfs: clean up log ticket overrun debug output
xfs: Clean up XFS_BLI_* flag namespace
xfs: modify buffer item reference counting
xfs: allow log ticket allocation to take allocation flags
xfs: Don't reuse the same transaction ID for duplicated transactions.
Update Documentation/filesystems/tmpfs.txt to describe the interaction of
tmpfs mount option memory policy with tasks' cpuset mems_allowed.
Note: the mount(8) man page [in the util-linux-ng package] requires
similiar updates.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Document the design of the delayed logging implementation. This
includes assumptions made, dead ends followed, the reasoning behind
the structuring of the code, the layout of various structures, how
things fit together, traps and pit-falls avoided, etc. This is all
too much to document in the code itself, so do it in a separate
file.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (31 commits)
dquot: Detect partial write error to quota file in write_blk() and add printk_ratelimit for quota error messages
ocfs2: Fix lock inversion in quotas during umount
ocfs2: Use __dquot_transfer to avoid lock inversion
ocfs2: Fix NULL pointer deref when writing local dquot
ocfs2: Fix estimate of credits needed for quota allocation
ocfs2: Fix quota locking
ocfs2: Avoid unnecessary block mapping when refreshing quota info
ocfs2: Do not map blocks from local quota file on each write
quota: Refactor dquot_transfer code so that OCFS2 can pass in its references
quota: unify quota init condition in setattr
quota: remove sb_has_quota_active in get/set_info
quota: unify ->set_dqblk
quota: unify ->get_dqblk
ext3: make barrier options consistent with ext4
quota: Make quota stat accounting lockless.
suppress warning: "quotatypes" defined but not used
ext3: Fix waiting on transaction during fsync
jbd: Provide function to check whether transaction will issue data barrier
ufs: add ufs speciffic ->setattr call
BKL: Remove BKL from ext2 filesystem
...
ext4 was updated to accept barrier/nobarrier mount options
in addition to the older barrier=0/1. The barrier story
is complex enough, we should help people by making the options
the same at least, even if the defaults are different.
This patch allows the barrier/nobarrier mount options for ext3,
while keeping nobarrier the default.
It also unconditionally displays barrier status in show_options,
and prints a message at mount time if barriers are not enabled,
just as ext4 does.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The first three paragraphs are almost verbatim taken from Eric's
commit message on the patch introducing network ns tags. The next
two paragraphs I wrote to be a brief high level overview. The last
section is taken from the commit message on "Implement sysfs tagged
directory support", but updated. Hopefully correctly.
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (23 commits)
nilfs2: disallow remount of snapshot from/to a regular mount
nilfs2: use huge_encode_dev/huge_decode_dev
nilfs2: update comment on deactivate_super at nilfs_get_sb
nilfs2: replace MS_VERBOSE with MS_SILENT
nilfs2: add missing initialization of s_mode
nilfs2: fix misuse of open_bdev_exclusive/close_bdev_exclusive
nilfs2: enlarge s_volume_name member in nilfs_super_block
nilfs2: use checkpoint number instead of timestamp to select super block
nilfs2: add missing endian conversion on super block magic number
nilfs2: make nilfs_sc_*_ops static
nilfs2: add kernel doc comments to persistent object allocator functions
nilfs2: change sc_timer from a pointer to an embedded one in struct nilfs_sc_info
nilfs2: remove nilfs_segctor_init() in segment.c
nilfs2: insert checkpoint number in segment summary header
nilfs2: add a print message after loading nilfs2
nilfs2: cleanup multi kmem_cache_{create,destroy} code
nilfs2: move out checksum routines to segment buffer code
nilfs2: move pointer to super root block into logs
nilfs2: change default of 'errors' mount option to 'remount-ro' mode
nilfs2: Combine nilfs_btree_release_path() and nilfs_btree_free_path()
...
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: (47 commits)
ocfs2: Silence a gcc warning.
ocfs2: Don't retry xattr set in case value extension fails.
ocfs2:dlm: avoid dlm->ast_lock lockres->spinlock dependency break
ocfs2: Reset xattr value size after xa_cleanup_value_truncate().
fs/ocfs2/dlm: Use kstrdup
fs/ocfs2/dlm: Drop memory allocation cast
Ocfs2: Optimize punching-hole code.
Ocfs2: Make ocfs2_find_cpos_for_left_leaf() public.
Ocfs2: Fix hole punching to correctly do CoW during cluster zeroing.
Ocfs2: Optimize ocfs2 truncate to use ocfs2_remove_btree_range() instead.
ocfs2: Block signals for mkdir/link/symlink/O_CREAT.
ocfs2: Wrap signal blocking in void functions.
ocfs2/dlm: Increase o2dlm lockres hash size
ocfs2: Make ocfs2_extend_trans() really extend.
ocfs2/trivial: Code cleanup for allocation reservation.
ocfs2: make ocfs2_adjust_resv_from_alloc simple.
ocfs2: Make nointr a default mount option
ocfs2/dlm: Make o2dlm domain join/leave messages KERN_NOTICE
o2net: log socket state changes
ocfs2: print node # when tcp fails
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits)
vlynq: make whole Kconfig-menu dependant on architecture
add descriptive comment for TIF_MEMDIE task flag declaration.
EEPROM: max6875: Header file cleanup
EEPROM: 93cx6: Header file cleanup
EEPROM: Header file cleanup
agp: use NULL instead of 0 when pointer is needed
rtc-v3020: make bitfield unsigned
PCI: make bitfield unsigned
jbd2: use NULL instead of 0 when pointer is needed
cciss: fix shadows sparse warning
doc: inode uses a mutex instead of a semaphore.
uml: i386: Avoid redefinition of NR_syscalls
fix "seperate" typos in comments
cocbalt_lcdfb: correct sections
doc: Change urls for sparse
Powerpc: wii: Fix typo in comment
i2o: cleanup some exit paths
Documentation/: it's -> its where appropriate
UML: Fix compiler warning due to missing task_struct declaration
UML: add kernel.h include to signal.c
...
* 'for-2.6.35' of git://linux-nfs.org/~bfields/linux: (45 commits)
Revert "nfsd4: distinguish expired from stale stateids"
nfsd: safer initialization order in find_file()
nfs4: minor callback code simplification, comment
NFSD: don't report compiled-out versions as present
nfsd4: implement reclaim_complete
nfsd4: nfsd4_destroy_session must set callback client under the state lock
nfsd4: keep a reference count on client while in use
nfsd4: mark_client_expired
nfsd4: introduce nfs4_client.cl_refcount
nfsd4: refactor expire_client
nfsd4: extend the client_lock to cover cl_lru
nfsd4: use list_move in move_to_confirmed
nfsd4: fold release_session into expire_client
nfsd4: rename sessionid_lock to client_lock
nfsd4: fix bare destroy_session null dereference
nfsd4: use local variable in nfs4svc_encode_compoundres
nfsd: further comment typos
sunrpc: centralise most calls to svc_xprt_received
nfsd4: fix unlikely race in session replay case
nfsd4: fix filehandle comment
...
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
genirq: Clear CPU mask in affinity_hint when none is provided
genirq: Add CPU mask affinity hint
genirq: Remove IRQF_DISABLED from core code
genirq: Run irq handlers with interrupts disabled
genirq: Introduce request_any_context_irq()
genirq: Expose irq_desc->node in proc/irq
Fixed up trivial conflicts in Documentation/feature-removal-schedule.txt
This is a mandatory operation. Also, here (not in open) is where we
should be committing the reboot recovery information.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Originally, commit d899bf7b ("procfs: provide stack information for
threads") attempted to introduce a new feature for showing where the
threadstack was located and how many pages are being utilized by the
stack.
Commit c44972f1 ("procfs: disable per-task stack usage on NOMMU") was
applied to fix the NO_MMU case.
Commit 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on
64-bit") was applied to fix a bug in ia32 executables being loaded.
Commit 9ebd4eba7 ("procfs: fix /proc/<pid>/stat stack pointer for kernel
threads") was applied to fix a bug which had kernel threads printing a
userland stack address.
Commit 1306d603f ('proc: partially revert "procfs: provide stack
information for threads"') was then applied to revert the stack pages
being used to solve a significant performance regression.
This patch nearly undoes the effect of all these patches.
The reason for reverting these is it provides an unusable value in
field 28. For x86_64, a fork will result in the task->stack_start
value being updated to the current user top of stack and not the stack
start address. This unpredictability of the stack_start value makes
it worthless. That includes the intended use of showing how much stack
space a thread has.
Other architectures will get different values. As an example, ia64
gets 0. The do_fork() and copy_process() functions appear to treat the
stack_start and stack_size parameters as architecture specific.
I only partially reverted c44972f1 ("procfs: disable per-task stack usage
on NOMMU") . If I had completely reverted it, I would have had to change
mm/Makefile only build pagewalk.o when CONFIG_PROC_PAGE_MONITOR is
configured. Since I could not test the builds without significant effort,
I decided to not change mm/Makefile.
I only partially reverted 89240ba0 ("x86, fs: Fix x86 procfs stack
information for threads on 64-bit") . I left the KSTK_ESP() change in
place as that seemed worthwhile.
Signed-off-by: Robin Holt <holt@sgi.com>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace the introduced i_sem by an i_mutex in the filesystem locking
documentation. This was introduced [1] after all occurrences were
already replaced in the same text [2]. However, the term "inode
semaphore" has not been replaced then, and it's replaced now.
[1] afddba49d1
[2] a7bc02f4f4
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Like ext3, nilfs has 'errors' mount option to allow specifying desired
behavior on severe errors.
Currently, the default action is 'errors=continue' and has potential
to advance filesystem corruption for severe errors.
This will change the action to 'errors=remount-ro' to avoid the issue.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The default behavior for directory reservations stays the same, but we add a
mount option so people can tweak the size of directory reservations
according to their workloads.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
The default reservation size of 4 (32-bit windows) is a bit too ambitious.
Scale it back to 16 bits (resv_level=2). I have been testing various sizes
on a 4-node cluster which runs a mixed workload that is heavily threaded.
With a 256MB local alloc, I get *roughly* the following levels of average file
fragmentation:
resv_level=0 70%
resv_level=1 21%
resv_level=2 23%
resv_level=3 24%
resv_level=4 60%
resv_level=5 did not test
resv_level=6 60%
resv_level=2 seemed like a good compromise between not letting windows be
too small, but not so big that heavier workloads will immediately suffer
without tuning.
This patch also change the behavior of directory reservations - they now
track file reservations. The previous compromise of giving directory
windows only 8 bits wound up fragmenting more at some window sizes because
file allocations had smaller unused windows to poach from.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
This patch improves Ocfs2 allocation policy by allowing an inode to
reserve a portion of the local alloc bitmap for itself. The reserved
portion (allocation window) is advisory in that other allocation
windows might steal it if the local alloc bitmap becomes
full. Otherwise, the reservations are honored and guaranteed to be
free. When the local alloc window is moved to a different portion of
the bitmap, existing reservations are discarded.
Reservation windows are represented internally by a red-black
tree. Within that tree, each node represents the reservation window of
one inode. An LRU of active reservations is also maintained. When new
data is written, we allocate it from the inodes window. When all bits
in a window are exhausted, we allocate a new one as close to the
previous one as possible. Should we not find free space, an existing
reservation is pulled off the LRU and cannibalized.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Fix obvious cases of "it's" being used when "its" was meant.
Signed-off-by: Francis Galiegue <fgaliegue@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This patch adds documentation for new 9P options introduced in
2.6.34.
Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
New documentation should have an entry in the 00-INDEX. Correct git
urls.
Signed-off-by: Cheng Renquan <crquan@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
commit 3f226aa1c (mempolicy: support mpol=local tmpfs mount option) added
new mpol=local mount option. but it didn't add a documentation.
This patch does it.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Expose irq_desc->node as /proc/irq/*/node.
This file provides device hardware locality information for apps
desiring to include hardware locality in irq mapping decisions.
Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (205 commits)
ceph: update for write_inode API change
ceph: reset osd after relevant messages timed out
ceph: fix flush_dirty_caps race with caps migration
ceph: include migrating caps in issued set
ceph: fix osdmap decoding when pools include (removed) snaps
ceph: return EBADF if waiting for caps on closed file
ceph: set osd request message front length correctly
ceph: reset front len on return to msgpool; BUG on mismatched front iov
ceph: fix snaptrace decoding on cap migration between mds
ceph: use single osd op reply msg
ceph: reset bits on connection close
ceph: remove bogus mds forward warning
ceph: remove fragile __map_osds optimization
ceph: fix connection fault STANDBY check
ceph: invalidate_authorizer without con->mutex held
ceph: don't clobber write return value when using O_SYNC
ceph: fix client_request_forward decoding
ceph: drop messages on unregistered mds sessions; cleanup
ceph: fix comments, locking in destroy_inode
ceph: move dereference after NULL test
...
Fix trivial conflicts in Documentation/ioctl/ioctl-number.txt
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (56 commits)
doc: fix typo in comment explaining rb_tree usage
Remove fs/ntfs/ChangeLog
doc: fix console doc typo
doc: cpuset: Update the cpuset flag file
Fix of spelling in arch/sparc/kernel/leon_kernel.c no longer needed
Remove drivers/parport/ChangeLog
Remove drivers/char/ChangeLog
doc: typo - Table 1-2 should refer to "status", not "statm"
tree-wide: fix typos "ass?o[sc]iac?te" -> "associate" in comments
No need to patch AMD-provided drivers/gpu/drm/radeon/atombios.h
devres/irq: Fix devm_irq_match comment
Remove reference to kthread_create_on_cpu
tree-wide: Assorted spelling fixes
tree-wide: fix 'lenght' typo in comments and code
drm/kms: fix spelling in error message
doc: capitalization and other minor fixes in pnp doc
devres: typo fix s/dev/devm/
Remove redundant trailing semicolons from macros
fix typo "definetly" -> "definitely" in comment
tree-wide: s/widht/width/g typo in comments
...
Fix trivial conflict in Documentation/laptops/00-INDEX
Make dnotify_test.c source file and add it to Makefile so that
bitrot can be prevented.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: 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>
* git://git.kernel.org/pub/scm/linux/kernel/git/joern/logfs:
[LogFS] Change magic number
[LogFS] Remove h_version field
[LogFS] Check feature flags
[LogFS] Only write journal if dirty
[LogFS] Fix bdev erases
[LogFS] Silence gcc
[LogFS] Prevent 64bit divisions in hash_index
[LogFS] Plug memory leak on error paths
[LogFS] Add MAINTAINERS entry
[LogFS] add new flash file system
Fixed up trivial conflict in lib/Kconfig, and a semantic conflict in
fs/logfs/inode.c introduced by write_inode() being changed to use
writeback_control' by commit a9185b41a4
("pass writeback_control to ->write_inode")
* 'for-2.6.34' of git://linux-nfs.org/~bfields/linux: (22 commits)
nfsd4: fix minor memory leak
svcrpc: treat uid's as unsigned
nfsd: ensure sockets are closed on error
Revert "sunrpc: move the close processing after do recvfrom method"
Revert "sunrpc: fix peername failed on closed listener"
sunrpc: remove unnecessary svc_xprt_put
NFSD: NFSv4 callback client should use RPC_TASK_SOFTCONN
xfs_export_operations.commit_metadata
commit_metadata export operation replacing nfsd_sync_dir
lockd: don't clear sm_monitored on nsm_reboot_lookup
lockd: release reference to nsm_handle in nlm_host_rebooted
nfsd: Use vfs_fsync_range() in nfsd_commit
NFSD: Create PF_INET6 listener in write_ports
SUNRPC: NFS kernel APIs shouldn't return ENOENT for "transport not found"
SUNRPC: Bury "#ifdef IPV6" in svc_create_xprt()
NFSD: Support AF_INET6 in svc_addsock() function
SUNRPC: Use rpc_pton() in ip_map_parse()
nfsd: 4.1 has an rfc number
nfsd41: Create the recovery entry for the NFSv4.1 client
nfsd: use vfs_fsync for non-directories
...
A frequent questions from users about memory management is what numbers of
swap ents are user for processes. And this information will give some
hints to oom-killer.
Besides we can count the number of swapents per a process by scanning
/proc/<pid>/smaps, this is very slow and not good for usual process
information handler which works like 'ps' or 'top'. (ps or top is now
enough slow..)
This patch adds a counter of swapents to mm_counter and update is at each
swap events. Information is exported via /proc/<pid>/status file as
[kamezawa@bluextal memory]$ cat /proc/self/status
Name: cat
State: R (running)
Tgid: 2910
Pid: 2910
PPid: 2823
TracerPid: 0
Uid: 500 500 500 500
Gid: 500 500 500 500
FDSize: 256
Groups: 500
VmPeak: 82696 kB
VmSize: 82696 kB
VmLck: 0 kB
VmHWM: 432 kB
VmRSS: 432 kB
VmData: 172 kB
VmStk: 84 kB
VmExe: 48 kB
VmLib: 1568 kB
VmPTE: 40 kB
VmSwap: 0 kB <=============== this.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Considering the nature of per mm stats, it's the shared object among
threads and can be a cache-miss point in the page fault path.
This patch adds per-thread cache for mm_counter. RSS value will be
counted into a struct in task_struct and synchronized with mm's one at
events.
Now, in this patch, the event is the number of calls to handle_mm_fault.
Per-thread value is added to mm at each 64 calls.
rough estimation with small benchmark on parallel thread (2threads) shows
[before]
4.5 cache-miss/faults
[after]
4.0 cache-miss/faults
Anyway, the most contended object is mmap_sem if the number of threads grows.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Hellwig