linux.git/fs/proc/proc_misc.c, branch v2.6.24

Unify /proc/slabinfo configuration

2008-01-02T21:04:48+00:00

Both SLUB and SLAB really did almost exactly the same thing for
/proc/slabinfo setup, using duplicate code and per-allocator #ifdef's.

This just creates a common CONFIG_SLABINFO that is enabled by both SLUB
and SLAB, and shares all the setup code.  Maybe SLOB will want this some
day too.

Reviewed-by: Pekka Enberg 
Signed-off-by: Linus Torvalds

slub: register slabinfo to procfs

2008-01-02T18:42:39+00:00

We need to register slabinfo to procfs when CONFIG_SLUB is enabled to
make the file actually visible to user-space.

Signed-off-by: Pekka Enberg 
Acked-by: Ingo Molnar 
Signed-off-by: Linus Torvalds

pid namespaces: define and use task_active_pid_ns() wrapper

2007-10-19T18:53:37+00:00

With multiple pid namespaces, a process is known by some pid_t in every
ancestor pid namespace.  Every time the process forks, the child process also
gets a pid_t in every ancestor pid namespace.

While a process is visible in >=1 pid namespaces, it can see pid_t's in only
one pid namespace.  We call this pid namespace it's "active pid namespace",
and it is always the youngest pid namespace in which the process is known.

This patch defines and uses a wrapper to find the active pid namespace of a
process.  The implementation of the wrapper will be changed in when support
for multiple pid namespaces are added.

Changelog:
	2.6.22-rc4-mm2-pidns1:
	- [Pavel Emelianov, Alexey Dobriyan] Back out the change to use
	  task_active_pid_ns() in child_reaper() since task->nsproxy
	  can be NULL during task exit (so child_reaper() continues to
	  use init_pid_ns).

	  to implement child_reaper() since init_pid_ns.child_reaper to
	  implement child_reaper() since tsk->nsproxy can be NULL during exit.

	2.6.21-rc6-mm1:
	- Rename task_pid_ns() to task_active_pid_ns() to reflect that a
	  process can have multiple pid namespaces.

Signed-off-by: Sukadev Bhattiprolu 
Acked-by: Pavel Emelianov 
Cc: Eric W. Biederman 
Cc: Cedric Le Goater 
Cc: Dave Hansen 
Cc: Serge Hallyn 
Cc: Herbert Poetzel 
Cc: Kirill Korotaev 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

report the per-irq statistics on all arches

2007-10-17T15:42:49+00:00

Commit 4004c69ad68dd03733179277280ea2946990ba36 avoids too many remote cpu
references while reporting per-irq stats.  Since we will not have the same
performance penalty of bringing in remote cpu cachelines while reporting
per-irq stats anymore, we can now afford to be consistent and report this
statistic on all arches, all configs.

akpm: affects ia64, alpha and ppc64, mainly.

Kiran earlier said:

Read to /proc/stat takes:
Plain: 	2.622832
With speedup patch: 0.013194
With the per-irq stats commented out: 0.008124

So the performance problems which originally caused those architectures to
disable this statistic should now be fixed up.

Signed-off-by: Ravikiran Thirumalai 
Cc: Paul Mackerras 
Cc: Benjamin Herrenschmidt 
Cc: "Luck, Tony" 
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Acked-by: Linus Torvalds 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo

2007-10-16T16:43:00+00:00

This patch provides fragmentation avoidance statistics via /proc/pagetypeinfo.
 The information is collected only on request so there is no runtime overhead.
 The statistics are in three parts:

The first part prints information on the size of blocks that pages are
being grouped on and looks like

Page block order: 10
Pages per block:  1024

The second part is a more detailed version of /proc/buddyinfo and looks like

Free pages count per migrate type at order       0      1      2      3      4      5      6      7      8      9     10
Node    0, zone      DMA, type    Unmovable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type  Reclaimable      1      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type      Movable      0      0      0      0      0      0      0      0      0      0      0
Node    0, zone      DMA, type      Reserve      0      4      4      0      0      0      0      1      0      1      0
Node    0, zone   Normal, type    Unmovable    111      8      4      4      2      3      1      0      0      0      0
Node    0, zone   Normal, type  Reclaimable    293     89      8      0      0      0      0      0      0      0      0
Node    0, zone   Normal, type      Movable      1      6     13      9      7      6      3      0      0      0      0
Node    0, zone   Normal, type      Reserve      0      0      0      0      0      0      0      0      0      0      4

The third part looks like

Number of blocks type     Unmovable  Reclaimable      Movable      Reserve
Node 0, zone      DMA            0            1            2            1
Node 0, zone   Normal            3           17           94            4

To walk the zones within a node with interrupts disabled, walk_zones_in_node()
is introduced and shared between /proc/buddyinfo, /proc/zoneinfo and
/proc/pagetypeinfo to reduce code duplication.  It seems specific to what
vmstat.c requires but could be broken out as a general utility function in
mmzone.c if there were other other potential users.

Signed-off-by: Mel Gorman 
Acked-by: Andy Whitcroft 
Acked-by: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'locks' of git://linux-nfs.org/~bfields/linux

2007-10-15T23:07:40+00:00

* 'locks' of git://linux-nfs.org/~bfields/linux:
  nfsd: remove IS_ISMNDLCK macro
  Rework /proc/locks via seq_files and seq_list helpers
  fs/locks.c: use list_for_each_entry() instead of list_for_each()
  NFS: clean up explicit check for mandatory locks
  AFS: clean up explicit check for mandatory locks
  9PFS: clean up explicit check for mandatory locks
  GFS2: clean up explicit check for mandatory locks
  Cleanup macros for distinguishing mandatory locks
  Documentation: move locks.txt in filesystems/
  locks: add warning about mandatory locking races
  Documentation: move mandatory locking documentation to filesystems/
  locks: Fix potential OOPS in generic_setlease()
  Use list_first_entry in locks_wake_up_blocks
  locks: fix flock_lock_file() comment
  Memory shortage can result in inconsistent flocks state
  locks: kill redundant local variable
  locks: reverse order of posix_locks_conflict() arguments

sched: guest CPU accounting: add guest-CPU /proc/stat field

2007-10-15T15:00:19+00:00

as recent CPUs introduce a third running state, after "user" and
"system", we need a new field, "guest", in cpustat to store the time
used by the CPU to run virtual CPU. Modify /proc/stat to display this
new field.

Signed-off-by: Laurent Vivier 
Acked-by: Avi Kivity 
Signed-off-by: Ingo Molnar

Rework /proc/locks via seq_files and seq_list helpers

2007-10-09T22:32:46+00:00

Currently /proc/locks is shown with a proc_read function, but its behavior
is rather complex as it has to manually handle current offset and buffer
length.  On the other hand, files that show objects from lists can be
easily reimplemented using the sequential files and the seq_list_XXX()
helpers.

This saves (as usually) 16 lines of code and more than 200 from
the .text section.

[akpm@linux-foundation.org: no externs in C]
[akpm@linux-foundation.org: warning fixes]
Signed-off-by: Pavel Emelyanov 
Cc: "J. Bruce Fields" 
Cc: Trond Myklebust 
Signed-off-by: Andrew Morton

x86_64: Avoid too many remote cpu references due to /proc/stat

2007-07-22T01:37:09+00:00

Too many remote cpu references due to /proc/stat.

On x86_64, with newer kernel versions, kstat_irqs is a bit of a problem.
On every call to kstat_irqs, the process brings in per-cpu data from all
online cpus.  Doing this for NR_IRQS, which is now 256 + 32 * NR_CPUS
results in (256+32*63) * 63 remote cpu references on a 64 cpu config.
/proc/stat is parsed by common commands like top, who etc, causing lots
of cacheline transfers

This statistic seems useless.  Other 'big iron' arches disable this.

AK: changed to remove for all SMP setups
AK: add comment

Signed-off-by: Ravikiran Thirumalai 
Signed-off-by: Andi Kleen 
Signed-off-by: Linus Torvalds

Avoid too many remote cpu references due to /proc/stat

2007-07-19T17:04:43+00:00

Optimize show_stat to collect per-irq information just once.

On x86_64, with newer kernel versions, kstat_irqs is a bit of a problem.
On every call to kstat_irqs, the process brings in per-cpu data from all
online cpus.  Doing this for NR_IRQS, which is now 256 + 32 * NR_CPUS
results in (256+32*63) * 63 remote cpu references on a 64 cpu config.
Considering the fact that we already compute this value per-cpu, we can
save on the remote references as below.

Signed-off-by: Alok N Kataria 
Signed-off-by: Ravikiran Thirumalai 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds