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Author SHA1 Message Date
Eric Dumazet
aacf682fd8 x86: atomic64: Improve atomic64_read()
Linus noticed that the 32-bit version of atomic64_read() was
being overly complex with re-reading the value and doing a
retry loop over that.

Instead we can just rely on cmpxchg8b returning either the new
value or returning the current value.

We can use any 'old' value, which will be faster as it can be
loaded via immediates. Using some value that is not equal to
the real value in memory the instruction gets faster.

This also has the advantage that the CPU could avoid dirtying
the cacheline.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
LKML-Reference: <alpine.LFD.2.01.0907021653030.3210@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-03 13:26:40 +02:00
Ingo Molnar
b7882b7c65 x86: atomic64: Move the 32-bit atomic64_t implementation to a .c file
Linus noted that the atomic64_t primitives are all inlines
currently which is crazy because these functions have a large
register footprint anyway.

Move them to a separate file: arch/x86/lib/atomic64_32.c

Also, while at it, rename all uses of 'unsigned long long' to
the much shorter u64.

This makes the appearance of the prototypes a lot nicer - and
it also uncovered a few bugs where (yet unused) API variants
had 'long' as their return type instead of u64.

[ More intrusive changes are not yet done in this patch. ]

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
LKML-Reference: <alpine.LFD.2.01.0907021653030.3210@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-03 13:26:39 +02:00
Eric Dumazet
bbf2a330d9 x86: atomic64: The atomic64_t data type should be 8 bytes aligned on 32-bit too
Locked instructions on two cache lines at once are painful. If
atomic64_t uses two cache lines, my test program is 10x slower.

The chance for that is significant: 4/32 or 12.5%.

Make sure an atomic64_t is 8 bytes aligned.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
LKML-Reference: <alpine.LFD.2.01.0907021653030.3210@localhost.localdomain>
[ changed it to __aligned(8) as per Andrew's suggestion ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-03 13:26:38 +02:00
Ingo Molnar
029e5b1636 perf report: Annotate variable initialization
Certain versions of GCC dont see the initialization that is done here:

  builtin-report.c: In function ‘__cmd_report’:
  builtin-report.c:1038: warning: ‘syms’ may be used uninitialized in this function

So annotate it with a NULL initialization.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-03 13:17:28 +02:00
Arnaldo Carvalho de Melo
30d7a77dd5 perf_counter tools: Adjust symbols in ET_EXEC files too
Ingo Molnar wrote:

> i just bisected a 'perf report' bug that would cause us to not
> resolve all user-space symbols in a 'git gc' run to:
>
> f5812a7a33 is first bad commit
> commit f5812a7a33
> Author: Arnaldo Carvalho de Melo <acme@redhat.com>
> Date:   Tue Jun 30 11:43:17 2009 -0300
>
>     perf_counter tools: Adjust only prelinked symbol's addresses

Rename ->prelinked to ->adjust_symbols and making what was done
only for prelinked libraries also to ET_EXEC binaries, such as
/usr/bin/git:

[acme@doppio pahole]$ readelf -h /usr/bin/git | grep Type
  Type:                              EXEC (Executable file)
[acme@doppio pahole]$

And after installing the 'git-debuginfo' package, I get correct results:

[acme@doppio linux-2.6-tip]$ perf report --sort comm,dso,symbol -d /usr/bin/git | head -20

 #
 # (1139614 samples)
 #
 # Overhead           Command  Shared Object              Symbol
 # ........  ................  .........................  ......
 #
    34.98%               git  /usr/bin/git               [.] send_sideband
    33.39%               git  /usr/bin/git               [.] enter_repo
     6.81%               git  /usr/bin/git               [.] diff_opt_parse
     4.95%               git  /usr/bin/git               [.] is_repository_shallow
     3.24%               git  /usr/bin/git               [.] odb_mkstemp
     1.39%               git  /usr/bin/git               [.] output
     1.34%               git  /usr/bin/git               [.] xmmap
     1.25%               git  /usr/bin/git               [.] receive_pack_config
     1.16%               git  /usr/bin/git               [.] git_pathdup
     0.90%               git  /usr/bin/git               [.] read_object_with_reference
     0.86%               git  /usr/bin/git               [.] show_patch_diff
     0.85%               git  /usr/bin/git               0x00000000095e2e
     0.69%               git  /usr/bin/git               [.] display
[acme@doppio linux-2.6-tip]$

I'll check what are the last cases where we can't resolve symbols, like
this 0x00000000095e2e later.

And I guess this will fix the problems Mike were seeing too:

 [acme@doppio linux-2.6-tip]$ readelf -h ../build/perf/vmlinux | grep Type
   Type:                              EXEC (Executable file)
 [acme@doppio linux-2.6-tip]$

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-03 08:24:13 +02:00
Frederic Weisbecker
24b57c6988 perf_counter tools: Display percents of hits in callchain with overhead colors
This adds the use of colors to signal at a glance the important
overhead thresholds in callchains hit rates.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246558475-10624-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 21:38:38 +02:00
Frederic Weisbecker
1e11fd82d2 perf_counter tools: Provide helper to print percents color
Among perf annotate, perf report and perf top, we can find the
common colored printing of percents according to the following
rules:

    High overhead =  > 5%, colored in red
    Mid overhead =  > 0.5%, colored in green
    Low overhead =  < 0.5%, default color

Factorize these multiple checks in a single function named
percent_color_fprintf() and also provide a get_percent_color()
for sites which print percentages and other things at the same
time.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246558475-10624-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 21:38:37 +02:00
Frederic Weisbecker
c20ab37ef3 perf_counter tools: Set the minimum percent for callchains to be displayed
Callchains output may become a burden on a trace because even
rarely hit site are exposed. This can be too much information.

Let the user set a threshold as a minimum percent of hits using
the new pattern for the -c option:

    -c mode,min_percent

Example:

$ perf report -s sym -c flat,4

     8.25%  [k] copy_user_generic_string
             4.19%
                copy_user_generic_string
                generic_file_aio_read
                do_sync_read
                vfs_read
                sys_pread64
                system_call_fastpath
                pread64

     5.39%  [k] search_by_key
     4.63%  0x00000000009e0a
     2.36%  [k] memcpy_c
[...]

$ perf report -s sym -c graph,2

     8.25%  [k] copy_user_generic_string
                |
                |--4.31%-- generic_file_aio_read
                |          do_sync_read
                |          vfs_read
                |          |
                |           --4.19%-- sys_pread64
                |                     system_call_fastpath
                |                     pread64
                |
                 --3.24%-- generic_file_buffered_write
                           __generic_file_aio_write_nolock
                           generic_file_aio_write
                           do_sync_write
                           reiserfs_file_write
                           vfs_write
                           |
                            --3.14%-- sys_pwrite64
                                      system_call_fastpath
                                      __pwrite64

     5.39%  [k] search_by_key
                |
                 --2.23%-- reiserfs_update_sd_size

     4.63%  0x00000000009e0a

     2.36%  [k] memcpy_c
[...]

You can also omit it and it will default to 0.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246558475-10624-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 21:38:37 +02:00
Frederic Weisbecker
4eb3e4788b perf report: Add support for callchain graph output
Currently, the printing of callchains is done in a single
vertical level, this is the "flat" mode:

8.25%  [k] copy_user_generic_string
             4.19%
                copy_user_generic_string
                generic_file_aio_read
                do_sync_read
                vfs_read
                sys_pread64
                system_call_fastpath
                pread64

This patch introduces a new "graph" mode which provides a
hierarchical output of factorized paths recursively sorted:

 8.25%  [k] copy_user_generic_string
                |
                |--4.31%-- generic_file_aio_read
                |          do_sync_read
                |          vfs_read
                |          |
                |          |--4.19%-- sys_pread64
                |          |          system_call_fastpath
                |          |          pread64
                |          |
                |           --0.12%-- sys_read
                |                     system_call_fastpath
                |                     __read
                |
                |--3.24%-- generic_file_buffered_write
                |          __generic_file_aio_write_nolock
                |          generic_file_aio_write
                |          do_sync_write
                |          reiserfs_file_write
                |          vfs_write
                |          |
                |          |--3.14%-- sys_pwrite64
                |          |          system_call_fastpath
                |          |          __pwrite64
                |          |
                |           --0.10%-- sys_write
[...]

The command line has then changed.

By providing the -c option, the callchain will output in the
flat mode by default.

But you can override it:

    perf report -c graph

or

    perf report -c flat

You can also pass the abreviated mode:

    perf report -c g

or

    perf report -c gra

will both make use of the graph mode.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246550301-8954-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 20:47:15 +02:00
Frederic Weisbecker
5a4b181721 perf_counter tools: Add new OPT_CALLBACK_DEFAULT option
There is no predefined macro to create an option that can have
a custom value or a default one if none is given.

This patch provides a new helper OPT_CALLBACK_DEFAULT() which
defines such kind of option.

For example, considering an option -c, we want to get the
default value in the following cases:

    perf command -c -d
    perf command -d -c

And the foo value when it's given:

    perf command -c foo -d
    perf command -d -c foo

That's also why PARSE_OPT_LASTARG_DEFAULT is extended here to
support default values whatever the position of the option, not
only in the end.

Should it now be renamed to PARSE_OPT_ARG_DEFAULT ?

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: git@vger.kernel.org
LKML-Reference: <1246550301-8954-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 20:47:14 +02:00
Frederic Weisbecker
14f4654cbd perf_counter tools: Create new chain_for_each_child() iterator
Iterating through children of a node in the callchain tree
shows something that may be quite confusing at a first glance.
The head is the children field of the parent and the list nodes
are in the brothers field of the children.

This is because the childs are linked to the parent as a list
of "brothers" using the "children" list of the parent as a
head:

  ---------------
 | Parent (head) |-------------------------------------
  ---------------                                      |
     |                                                 |
  children                                             |
     |                                                 |
  -----------               -----------                |
 | 1st child |---brother---| 2nd child |---brother-----
  -----------               -----------

This makes the following strange pattern often occuring:

 list_for_each_entry(child, &parent->children, brothers) {
        // do something with children
 }

Abstract it to chain_for_each_child() to factorize and simplify
this pattern.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246550301-8954-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 20:47:14 +02:00
Mike Galbraith
429764873c perf_counter tools: Enable kernel module symbol loading in tools
Add the -m/--modules option to perf report and perf annotate,
which enables live module symbol/image loading. To be used
with -k/--vmlinux.

(Also give perf annotate a -P/--full-paths option.)

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246514986.13293.48.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 08:42:21 +02:00
Mike Galbraith
6cfcc53ed4 perf_counter tools: Connect module support infrastructure to symbol loading infrastructure
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246514916.13293.46.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 08:42:21 +02:00
Mike Galbraith
208b4b4a59 perf_counter tools: Add infrastructure to support loading of kernel module symbols
Add infrastructure for module path discovery and section load addresses.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246514830.13293.44.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 08:42:20 +02:00
Mike Galbraith
9974f49678 perf_counter tools: Make symbol loading consistently return number of loaded symbols
perf_counter tools: Make symbol loading consistently return number of loaded symbols.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246514758.13293.42.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 08:42:20 +02:00
Frederic Weisbecker
a92bef0f21 perf stat: Handle pipe read failures in perf stat
Building builtin-stat.c reports the following errors:

cc1: warnings being treated as errors
builtin-stat.c: In function ‘run_perf_stat’:
builtin-stat.c:242: erreur: ignoring return value of ‘read’, declared with attribute warn_unused_result
builtin-stat.c:255: erreur: ignoring return value of ‘read’, declared with attribute warn_unused_result
make: *** [builtin-stat.o] Erreur 1

This patch handles the possible pipe read failures.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246474930-6088-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 22:37:24 +02:00
Frederic Weisbecker
0406ca6d8e perf_counter: Ignore the nmi call frames in the x86-64 backtraces
About every callchains recorded with perf record are filled up
including the internal perfcounter nmi frame:

 perf_callchain
 perf_counter_overflow
 intel_pmu_handle_irq
 perf_counter_nmi_handler
 notifier_call_chain
 atomic_notifier_call_chain
 notify_die
 do_nmi
 nmi

We want ignore this frame as it's not interesting for
instrumentation. To solve this, we simply ignore every frames
from nmi context.

New example of "perf report -s sym -c" after this patch:

9.59%  [k] search_by_key
             4.88%
                search_by_key
                reiserfs_read_locked_inode
                reiserfs_iget
                reiserfs_lookup
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                vfs_fstatat
                vfs_lstat
                sys_newlstat
                system_call_fastpath
                __lxstat
                0x406fb1

             3.19%
                search_by_key
                search_by_entry_key
                reiserfs_find_entry
                reiserfs_lookup
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                vfs_fstatat
                vfs_lstat
                sys_newlstat
                system_call_fastpath
                __lxstat
                0x406fb1
[...]

For now this patch only solves the problem in x86-64.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246474930-6088-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 22:37:23 +02:00
Arnaldo Carvalho de Melo
5da5025858 perf_counter tools: Share list.h with the kernel
The copy we were using came from another copy I did for the dwarves
(pahole) package, that came from the kernel years ago.

The only function that is used by the perf tools and that isn't in the
kernel is list_del_range, that I'm leaving in the perf tools only for
now.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20090701174608.GA5823@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 22:37:23 +02:00
Arnaldo Carvalho de Melo
43cbcd8acb perf_counter tools: Share rbtree.with the kernel
The tools/perf/util/rbtree.c copy already drifted by three
csets:

 4b324126e0
 4c60117811
 16c047add3

So remove the copy and use the lib/rbtree.c directly, sharing
the source code while still generating a separate object file,
since tools/perf uses a far more agressive -O6 switch.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090701152837.GG15682@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 22:37:22 +02:00
Jaswinder Singh Rajput
73c24cb86c perf list: Add cache events
After:

$ ./perf list

List of pre-defined events (to be used in -e):

  cpu-cycles OR cycles                     [Hardware event]
  instructions                             [Hardware event]
  cache-references                         [Hardware event]
  cache-misses                             [Hardware event]
  branch-instructions OR branches          [Hardware event]
  branch-misses                            [Hardware event]
  bus-cycles                               [Hardware event]

  cpu-clock                                [Software event]
  task-clock                               [Software event]
  page-faults OR faults                    [Software event]
  minor-faults                             [Software event]
  major-faults                             [Software event]
  context-switches OR cs                   [Software event]
  cpu-migrations OR migrations             [Software event]

  L1-d$-loads                              [Hardware cache event]
  L1-d$-load-misses                        [Hardware cache event]
  L1-d$-stores                             [Hardware cache event]
  L1-d$-store-misses                       [Hardware cache event]
  L1-d$-prefetches                         [Hardware cache event]
  L1-d$-prefetch-misses                    [Hardware cache event]
  L1-i$-loads                              [Hardware cache event]
  L1-i$-load-misses                        [Hardware cache event]
  L1-i$-prefetches                         [Hardware cache event]
  L1-i$-prefetch-misses                    [Hardware cache event]
  LLC-loads                                [Hardware cache event]
  LLC-load-misses                          [Hardware cache event]
  LLC-stores                               [Hardware cache event]
  LLC-store-misses                         [Hardware cache event]
  LLC-prefetches                           [Hardware cache event]
  LLC-prefetch-misses                      [Hardware cache event]
  dTLB-loads                               [Hardware cache event]
  dTLB-load-misses                         [Hardware cache event]
  dTLB-stores                              [Hardware cache event]
  dTLB-store-misses                        [Hardware cache event]
  dTLB-prefetches                          [Hardware cache event]
  dTLB-prefetch-misses                     [Hardware cache event]
  iTLB-loads                               [Hardware cache event]
  iTLB-load-misses                         [Hardware cache event]
  branch-loads                             [Hardware cache event]
  branch-load-misses                       [Hardware cache event]

  rNNN                                     [raw hardware event descriptor]

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1246453578.3072.1.camel@ht.satnam>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 15:25:03 +02:00
Jaswinder Singh Rajput
b9ebdcc0ce perf stat: Define MATCH_EVENT for easy attr checking
MATCH_EVENT is useful:

 1. for multiple attrs checking
 2. avoid repetition of PERF_TYPE_ and PERF_COUNT_ and save space
 3. avoids line breakage

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1246440909.3403.5.camel@hpdv5.satnam>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 13:28:38 +02:00
Ingo Molnar
f37a291c52 perf_counter tools: Add more warnings and fix/annotate them
Enable -Wextra. This found a few real bugs plus a number
of signed/unsigned type mismatches/uncleanlinesses. It
also required a few annotations

All things considered it was still worth it so lets try with
this enabled for now.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 12:49:48 +02:00
Ingo Molnar
88a69dfbc6 perf report: Fix HV bit mismerge
Fix:

 builtin-report.c: In function ‘hist_entry__add’:
 builtin-report.c:1015: error: case label not within a switch statement
 builtin-report.c:1017: error: break statement not within loop or switch

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 11:17:40 +02:00
Paul Mackerras
61c45981dd perf_counter tools: Rework event string parsing/syntax
This reworks the parser for event descriptors to make it more
consistent in what it accepts.  It is now structured as a
recursive descent parser for the following grammar:

events		::= event ( ("," | space) space* event )*
event		::= ( raw_event | numeric_event | symbolic_event |
		      generic_hw_event ) [ event_modifier ]
raw_event	::= "r" hex_number
numeric_event	::= number ":" number
number		::= decimal_number | "0x" hex_number | "0" octal_number
symbolic_event	::= string_from_event_symbols_array
generic_hw_event::= cache_type ( "-" ( cache_op | cache_result ) )*
event_modifier	::= ":" ( "u" | "k" | "h" )+

with the extra restriction that you can have at most one
cache_op and at most one cache_result.

We pass the current string pointer by reference (i.e. as a
const char **) to the various parsing functions so that they
can advance the pointer to indicate how much they consumed.
They return 0 if they didn't recognize the thing at the pointer
or 1 if they did (and advance the pointer past it).

This also fixes parse_aliases to take the longest matching
alias from the table, not the first one.  Otherwise "l1-data"
would match the "l1-d" alias and the "ata" would not be
consumed.

This allows event modifiers indicating what processor modes to
count in to be applied to any event, not just numeric events,
and adds a ":h" modifier to indicate counting in hypervisor
mode.  Specifying ":u" now sets both exclude_kernel and
exclude_hv, and so on.  Multiple modes can be specified, e.g.
":uk" will count in user or hypervisor mode (i.e. only
exclude_kernel will be set).

Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <19018.53826.843815.189847@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 10:23:17 +02:00
Anton Blanchard
0a456fc58f powerpc/perf_counter: Enable alternate PR/HV bits for POWER7
POWER7 has the same PR/HV bit layout as POWER6, so set the flag.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: a.p.zijlstra@chello.nl
Cc: benh@kernel.crashing.org
LKML-Reference: <20090701030701.GI3563@kryten>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 10:20:28 +02:00
Frederic Weisbecker
deac911cbd perf_counter tools: Various fixes for callchains
The symbol resolving has of course revealed some bugs in the
callchain tree handling. This patch fixes some of them,
including:

- inherit the children from the parents while splitting a node
- fix list range moving
- fix indexes setting in callchains
- create a child on the current node if the path doesn't match in
  the existent children (was only done on the root)
- compare using symbols when possible so that we can match a function
  using any ip inside by referring to its start address.

The practical effects are:

- remove double callchains
- fix upside down or any random order of callchains
- fix wrong paths
- fix bad hits and percentage accounts

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246419315-9968-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 09:58:52 +02:00
Frederic Weisbecker
4424961ad6 perf_counter tools: Resolve symbols in callchains
This patch resolves the names, when possible, of each ip
present in the callchains while using the -c option with perf
report.

Example:

5.40%  [k] __d_lookup
             5.37%
                perf_callchain
                perf_counter_overflow
                intel_pmu_handle_irq
                perf_counter_nmi_handler
                notifier_call_chain
                atomic_notifier_call_chain
                notify_die
                do_nmi
                nmi
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                sys_faccessat
                sys_access
                system_call_fastpath
                0x7fb609846f77

             0.01%
                perf_callchain
                perf_counter_overflow
                intel_pmu_handle_irq
                perf_counter_nmi_handler
                notifier_call_chain
                atomic_notifier_call_chain
                notify_die
                do_nmi
                nmi
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                sys_faccessat

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246419315-9968-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 09:58:26 +02:00
Frederic Weisbecker
9198aa77b6 perf_counter tools: Fix storage size allocation of callchain list
Fix a confusion while giving the size of a callchain list
during its allocation. We are using the wrong structure size.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246419315-9968-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 09:58:23 +02:00
Ingo Molnar
087021ba41 Merge branch 'linus' into perfcounters/urgent
Merge reason: this branch was on a .30-ish base before, update
              it to an almost-.31-rc2 upstream base to pick up fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 09:56:26 +02:00
Linus Torvalds
e83c2b0ff3 Merge branch 'kmemleak' of git://linux-arm.org/linux-2.6
* 'kmemleak' of git://linux-arm.org/linux-2.6:
  kmemleak: Inform kmemleak about pid_hash
  kmemleak: Do not warn if an unknown object is freed
  kmemleak: Do not report new leaked objects if the scanning was stopped
  kmemleak: Slightly change the policy on newly allocated objects
  kmemleak: Do not trigger a scan when reading the debug/kmemleak file
  kmemleak: Simplify the reports logged by the scanning thread
  kmemleak: Enable task stacks scanning by default
  kmemleak: Allow the early log buffer to be configurable.
2009-06-30 19:04:53 -07:00
Linus Torvalds
9fcfc91bda Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm table: fix blk_stack_limits arg to use bytes not sectors
  dm exception store: really fix type lookup
2009-06-30 19:04:14 -07:00
Linus Torvalds
55bcab4695 Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (47 commits)
  perf report: Add --symbols parameter
  perf report: Add --comms parameter
  perf report: Add --dsos parameter
  perf_counter tools: Adjust only prelinked symbol's addresses
  perf_counter: Provide a way to enable counters on exec
  perf_counter tools: Reduce perf stat measurement overhead/skew
  perf stat: Use percentages for scaling output
  perf_counter, x86: Update x86_pmu after WARN()
  perf stat: Micro-optimize the code: memcpy is only required if no event is selected and !null_run
  perf stat: Improve output
  perf stat: Fix multi-run stats
  perf stat: Add -n/--null option to run without counters
  perf_counter tools: Remove dead code
  perf_counter: Complete counter swap
  perf report: Print sorted callchains per histogram entries
  perf_counter tools: Prepare a small callchain framework
  perf record: Fix unhandled io return value
  perf_counter tools: Add alias for 'l1d' and 'l1i'
  perf-report: Add bare minimum PERF_EVENT_READ parsing
  perf-report: Add modes for inherited stats and no-samples
  ...
2009-06-30 19:02:59 -07:00
Linus Torvalds
58580c8645 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  Add Fenghua Yu as temporary co-maintainer for ia64
  [IA64] address compiler warnings perfmon.c/salinfo.c
  [IA64] Remove unnecessary semicolons
  [IA64] sprintf should not be used with same source & destination address
2009-06-30 19:01:52 -07:00
David Howells
6086071005 MN10300: Wire up new syscalls
Wire up new syscalls rt_tgsigqueueinfo and perf_counter_open.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:58:37 -07:00
David Howells
aee3ff1b41 FRV: Wire up new syscalls
Wire up new syscalls rt_tgsigqueueinfo and perf_counter_open.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:58:37 -07:00
Wolfgang Illmeyer
752fa51e4c hostfs: set maximum filesize in superblock for proper LFS support
Maximum file size for hostfs mounts defaults to 2GB, so bigger files cannot be
read/written through hostfs. This patch initializes the maximum file size to
MAX_LFS_SIZE.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13531

Signed-off-by: Wolfgang Illmeyer <wolfgang@illmeyer.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:03 -07:00
Jiri Slaby
8516a50002 floppy: fix lock imbalance
A crappy macro prevents us unlocking on a fail path.

Expand the macro and unlock appropriatelly.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Mike Frysinger
9980060bad bfin: delay IRQ registration until driver is ready
Make sure we do not actually request the RTC IRQ until the device driver
is fully ready to handle and process any interrupt.  This way a spurious
interrupt won't crash the system (which may happen if the bootloader was
poking the RTC right before booting Linux).

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Ville Syrjala
ee905d0c58 atyfb: fix alignment for block writes
Block writes require 64 byte alignment.  Since block writes could be used
with SGRAM or WRAM also refine the memory type detection to check for
either type before deciding to use the 64 byte alignment.

Signed-off-by: Ville Syrjala <syrjala@sci.fi>
Tested-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Ville Syrjala
eafad22a05 atyfb: fix HP OmniBook 500 reboot hang
Apparently HP OmniBook 500's BIOS doesn't like the way atyfb reprograms
the hardware. The BIOS will simply hang after a reboot. Fix the problem
by restoring the hardware to it's original state on reboot.

Signed-off-by: Ville Syrjala <syrjala@sci.fi>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Baruch Siach
50efacf671 gpio: pl061: fix IRQ handling for GPIOs >= PL061_GPIO_NR
IRQ handling is wrong for any GPIO >= PL061_GPIO_NR.

Fix this by implementing and using a proper .to_irq method.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Baruch Siach
79d7f4ee23 gpio: pl061: fix probe error handling code
Note that IRQ has not been initialized when kmalloc() fails.

Also, use DECLARE_BITMAP() to make the code clearer.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Yinghai Lu
66918dcdf9 x86: only clear node_states for 64bit
Nathan reported that

| commit 73d60b7f74
| Author: Yinghai Lu <yinghai@kernel.org>
| Date:   Tue Jun 16 15:33:00 2009 -0700
|
|    page-allocator: clear N_HIGH_MEMORY map before we set it again
|
|    SRAT tables may contains nodes of very small size.  The arch code may
|    decide to not activate such a node.  However, currently the early boot
|    code sets N_HIGH_MEMORY for such nodes.  These nodes therefore seem to be
|    active although these nodes have no present pages.
|
|    For 64bit N_HIGH_MEMORY == N_NORMAL_MEMORY, so that works for 64 bit too

unintentionally and incorrectly clears the cpuset.mems cgroup attribute on
an i386 kvm guest, meaning that cpuset.mems can not be used.

Fix this by only clearing node_states[N_NORMAL_MEMORY] for 64bit only.
and need to do save/restore for that in find_zone_movable_pfn

Reported-by: Nathan Lynch <ntl@pobox.com>
Tested-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Nikanth Karthikesan
b37f2d4de6 cpusets: document adding/removing cpus to cpuset elaborately
By writing a tasks's pid to the file, a process adds that task to that
cgroup/cpuset.  But to add a cpu/mem to a cpuset, the new list of cpus
should be written to the cpuset.mems file which would replace the old list
of cpus.  Make this clearer in the documentation.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Richard Kennedy
d7831a0bdf mm: prevent balance_dirty_pages() from doing too much work
balance_dirty_pages can overreact and move all of the dirty pages to
writeback unnecessarily.

balance_dirty_pages makes its decision to throttle based on the number of
dirty plus writeback pages that are over the calculated limit,so it will
continue to move pages even when there are plenty of pages in writeback
and less than the threshold still dirty.

This allows it to overshoot its limits and move all the dirty pages to
writeback while waiting for the drives to catch up and empty the writeback
list.

A simple fio test easily demonstrates this problem.

fio --name=f1 --directory=/disk1 --size=2G -rw=write --name=f2 --directory=/disk2 --size=1G --rw=write --startdelay=10

This is the simplest fix I could find, but I'm not entirely sure that it
alone will be enough for all cases.  But it certainly is an improvement on
my desktop machine writing to 2 disks.

Do we need something more for machines with large arrays where
bdi_threshold * number_of_drives is greater than the dirty_ratio ?

Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:01 -07:00
Renaud Lottiaux
df279ca896 bsdacct: fix access to invalid filp in acct_on()
The file opened in acct_on and freshly stored in the ns->bacct struct can
be closed in acct_file_reopen by a concurrent call after we release
acct_lock and before we call mntput(file->f_path.mnt).

Record file->f_path.mnt in a local variable and use this variable only.

Signed-off-by: Renaud Lottiaux <renaud.lottiaux@kerlabs.com>
Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:00 -07:00
Joe Perches
b4f90189dc MAINTAINERS: STARFIRE/DURALAN update
Ion's cs.columbia.edu email address no longer works.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Ion Badulescu <ionut@badula.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:00 -07:00
Zhang Rui
8bc1ad7dd3 kernel/resource.c: fix sign extension in reserve_setup()
When the 32-bit signed quantities get assigned to the u64 resource_size_t,
they are incorrectly sign-extended.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13253
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=9905

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reported-by: Leann Ogasawara <leann@ubuntu.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Reported-by: <pablomme@googlemail.com>
Tested-by: <pablomme@googlemail.com>
Cc: <stable@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:00 -07:00
David Brownell
529ba0d966 spi: bitbang bugfix in message setup
Bugfix to spi_bitbang infrastructure: make sure to always set transfer
parameters on the first pass through the message's per-transfer loop.
This can matter with drivers that replace the per-word or per-buffer
transfer primitives, on busses with multiple SPI devices.

Previously, this could have started messages using the settings left after
previous messages.  The problem was observed when a high speed chip
(m25p80 type flash) was running very slowly because a low speed device
(avr8 microcontroller) had previously used the bus.  Similar faults could
have driven the low speed device too fast, or used an unexpected word
size.

Acked-by: Steven A. Falco <sfalco@harris.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:00 -07:00
Krzysztof Helt
537a1bf059 fbdev: add mutex for fb_mmap locking
Add a mutex to avoid a circular locking problem between the mm layer
semaphore and fbdev ioctl mutex through the fb_mmap() call.

Also, add mutex to all places where smem_start and smem_len fields change
so the mutex inside the fb_mmap() is actually used.  Changing of these
fields before calling the framebuffer_register() are not mutexed.

This is 2.6.31 material.  It removes one lockdep (fb_mmap() and
register_framebuffer()) but there is still another one (fb_release() and
register_framebuffer()).  It also cleans up handling of the smem_start and
smem_len fields used by mutexed section of the fb_mmap().

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:00 -07:00