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  1. 02 Jun, 2011 9 commits
  3. 28 May, 2011 10 commits
  5. 27 May, 2011 7 commits
  7. 26 May, 2011 14 commits
    • Arnaldo Carvalho de Melo's avatar
      perf tools: Fix build on older systems · 75911c9b
      Arnaldo Carvalho de Melo authored 
      Where /usr/include/linux/const.h is not present, e.g. RHEL5.
Reported-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/n/tip-ypcw2mu0w7dl1rrc6ncz3pee@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      75911c9b
    • Arnaldo Carvalho de Melo's avatar
      perf symbols: Handle /proc/sys/kernel/kptr_restrict · ec80fde7
      Arnaldo Carvalho de Melo authored 
      Perf uses /proc/modules to figure out where kernel modules are loaded.

With the advent of kptr_restrict, non root users get zeroes for all module
start addresses.

So check if kptr_restrict is non zero and don't generate the syntethic
PERF_RECORD_MMAP events for them.

Warn the user about it in perf record and in perf report.

In perf report the reference relocation symbol being zero means that
kptr_restrict was set, thus /proc/kallsyms has only zeroed addresses, so don't
use it to fixup symbol addresses when using a valid kallsyms (in the buildid
cache) or vmlinux (in the vmlinux path) build-id located automatically or
specified by the user.

Provide an explanation about it in 'perf report' if kernel samples were taken,
checking if a suitable vmlinux or kallsyms was found/specified.

Restricted /proc/kallsyms don't go to the buildid cache anymore.

Example:

 [acme@emilia ~]$ perf record -F 100000 sleep 1

 WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted, check
 /proc/sys/kernel/kptr_restrict.

 Samples in kernel functions may not be resolved if a suitable vmlinux file is
 not found in the buildid cache or in the vmlinux path.

 Samples in kernel modules won't be resolved at all.

 If some relocation was applied (e.g. kexec) symbols may be misresolved even
 with a suitable vmlinux or kallsyms file.

 [ perf record: Woken up 1 times to write data ]
 [ perf record: Captured and wrote 0.005 MB perf.data (~231 samples) ]
 [acme@emilia ~]$

 [acme@emilia ~]$ perf report --stdio
 Kernel address maps (/proc/{kallsyms,modules}) were restricted,
 check /proc/sys/kernel/kptr_restrict before running 'perf record'.

 If some relocation was applied (e.g. kexec) symbols may be misresolved.

 Samples in kernel modules can't be resolved as well.

 # Events: 13  cycles
 #
 # Overhead  Command      Shared Object                 Symbol
 # ........  .......  .................  .....................
 #
    20.24%    sleep  [kernel.kallsyms]  [k] page_fault
    20.04%    sleep  [kernel.kallsyms]  [k] filemap_fault
    19.78%    sleep  [kernel.kallsyms]  [k] __lru_cache_add
    19.69%    sleep  ld-2.12.so         [.] memcpy
    14.71%    sleep  [kernel.kallsyms]  [k] dput
     4.70%    sleep  [kernel.kallsyms]  [k] flush_signal_handlers
     0.73%    sleep  [kernel.kallsyms]  [k] perf_event_comm
     0.11%    sleep  [kernel.kallsyms]  [k] native_write_msr_safe

 #
 # (For a higher level overview, try: perf report --sort comm,dso)
 #
 [acme@emilia ~]$

This is because it found a suitable vmlinux (build-id checked) in
/lib/modules/2.6.39-rc7+/build/vmlinux (use -v in perf report to see the long
file name).

If we remove that file from the vmlinux path:

 [root@emilia ~]# mv /lib/modules/2.6.39-rc7+/build/vmlinux \
		     /lib/modules/2.6.39-rc7+/build/vmlinux.OFF
 [acme@emilia ~]$ perf report --stdio
 [kernel.kallsyms] with build id 57298cdbe0131f6871667ec0eaab4804dcf6f562
 not found, continuing without symbols

 Kernel address maps (/proc/{kallsyms,modules}) were restricted, check
 /proc/sys/kernel/kptr_restrict before running 'perf record'.

 As no suitable kallsyms nor vmlinux was found, kernel samples can't be
 resolved.

 Samples in kernel modules can't be resolved as well.

 # Events: 13  cycles
 #
 # Overhead  Command      Shared Object  Symbol
 # ........  .......  .................  ......
 #
    80.31%    sleep  [kernel.kallsyms]  [k] 0xffffffff8103425a
    19.69%    sleep  ld-2.12.so         [.] memcpy

 #
 # (For a higher level overview, try: perf report --sort comm,dso)
 #
 [acme@emilia ~]$
Reported-by: default avatarStephane Eranian <eranian@google.com>
Suggested-by: default avatarDavid Miller <davem@davemloft.net>
Cc: Dave Jones <davej@redhat.com>
Cc: David Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/n/tip-mt512joaxxbhhp1odop04yit@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      ec80fde7
    • Jesper Juhl's avatar
      perf: Remove duplicate headers · ea7659fb
      Jesper Juhl authored 
      Signed-off-by: default avatarJesper Juhl <jj@chaosbits.net>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: trivial@kernel.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1105261011290.17400@swampdragon.chaosbits.netSigned-off-by: default avatarIngo Molnar <mingo@elte.hu>
      ea7659fb
    • Ingo Molnar's avatar
      Merge branch 'linus' into perf/urgent · 1102c660
      Ingo Molnar authored 
      Merge reason: Linus applied an overlapping commit:

  5f2e8e2b: kernel/watchdog.c: Use proper ANSI C prototypes

So merge it in to make sure we can iterate the file without conflicts.
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      1102c660
    • Eric Paris's avatar
      tmpfs: fix XATTR N overriding POSIX_ACL Y · 4db70f73
      Eric Paris authored 
      Choosing TMPFS_XATTR default N was switching off TMPFS_POSIX_ACL,
even if it had been Y in oldconfig; and Linus reports that PulseAudio
goes subtly wrong unless it can use ACLs on /dev/shm.

Make TMPFS_POSIX_ACL select TMPFS_XATTR (and depend upon TMPFS),
and move the TMPFS_POSIX_ACL entry before the TMPFS_XATTR entry,
to avoid asking unnecessary questions then ignoring their answers.
Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4db70f73
    • Steven Rostedt's avatar
      ftrace: Add internal recursive checks · b1cff0ad
      Steven Rostedt authored 
      Witold reported a reboot caused by the selftests of the dynamic function
tracer. He sent me a config and I used ktest to do a config_bisect on it
(as my config did not cause the crash). It pointed out that the problem
config was CONFIG_PROVE_RCU.

What happened was that if multiple callbacks are attached to the
function tracer, we iterate a list of callbacks. Because the list is
managed by synchronize_sched() and preempt_disable, the access to the
pointers uses rcu_dereference_raw().

When PROVE_RCU is enabled, the rcu_dereference_raw() calls some
debugging functions, which happen to be traced. The tracing of the debug
function would then call rcu_dereference_raw() which would then call the
debug function and then... well you get the idea.

I first wrote two different patches to solve this bug.

1) add a __rcu_dereference_raw() that would not do any checks.
2) add notrace to the offending debug functions.

Both of these patches worked.

Talking with Paul McKenney on IRC, he suggested to add recursion
detection instead. This seemed to be a better solution, so I decided to
implement it. As the task_struct already has a trace_recursion to detect
recursion in the ring buffer, and that has a very small number it
allows, I decided to use that same variable to add flags that can detect
the recursion inside the infrastructure of the function tracer.

I plan to change it so that the task struct bit can be checked in
mcount, but as that requires changes to all archs, I will hold that off
to the next merge window.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1306348063.1465.116.camel@gandalf.stny.rr.comReported-by: default avatarWitold Baryluk <baryluk@smp.if.uj.edu.pl>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      b1cff0ad
    • liubo's avatar
      tracing: Update btrfs's tracepoints to use u64 interface · 7f34b746
      liubo authored 
      To avoid 64->32 truncating WARNING, update btrfs's tracepoints.
Signed-off-by: default avatarLiu Bo <liubo2009@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/4DACE6E3.8080200@cn.fujitsu.comSigned-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      7f34b746
    • liubo's avatar
      tracing: Add __print_symbolic_u64 to avoid warnings on 32bit machine · 2fc1b6f0
      liubo authored 
      Filesystem, like Btrfs, has some "ULL" macros, and when these macros are passed
to tracepoints'__print_symbolic(), there will be 64->32 truncate WARNINGS during
compiling on 32bit box.
Signed-off-by: default avatarLiu Bo <liubo2009@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/4DACE6E0.7000507@cn.fujitsu.comSigned-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      2fc1b6f0
    • Steven Rostedt's avatar
      ftrace: Set ops->flag to enabled even on static function tracing · 3b6cfdb1
      Steven Rostedt authored 
      When dynamic ftrace is not configured, the ops->flags still needs
to have its FTRACE_OPS_FL_ENABLED bit set in ftrace_startup().
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      3b6cfdb1
    • Steven Rostedt's avatar
      tracing: Have event with function tracer check error return · 17bb615a
      Steven Rostedt authored 
      The self tests for event tracer does not check if the function
tracing was successfully activated. It needs to before it continues
the tests, otherwise the wrong errors may be reported.
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      17bb615a
    • Steven Rostedt's avatar
      ftrace: Have ftrace_startup() return failure code · a1cd6173
      Steven Rostedt authored 
      The register_ftrace_function() returns an error code on failure
except if the call to ftrace_startup() fails. Add a error return to
ftrace_startup() if it fails to start, allowing register_ftrace_funtion()
to return a proper error value.
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      a1cd6173
    • Stephen Rothwell's avatar
      video: mb862xx: udelay need linux/delay.h · 520fd845
      Stephen Rothwell authored 
      Fix this:

  drivers/video/mb862xx/mb862xx-i2c.c: In function 'mb862xx_i2c_wait_event':
  drivers/video/mb862xx/mb862xx-i2c.c:25: error: implicit declaration of function 'udelay'

caused by commit f8a6b1f4 ("video: mb862xx: add support for
controller's I2C bus adapter").
Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      520fd845
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/linux-2.6-nsfd · 14d74e0c
      Linus Torvalds authored 
      * git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/linux-2.6-nsfd:
  net: fix get_net_ns_by_fd for !CONFIG_NET_NS
  ns proc: Return -ENOENT for a nonexistent /proc/self/ns/ entry.
  ns: Declare sys_setns in syscalls.h
  net: Allow setting the network namespace by fd
  ns proc: Add support for the ipc namespace
  ns proc: Add support for the uts namespace
  ns proc: Add support for the network namespace.
  ns: Introduce the setns syscall
  ns: proc files for namespace naming policy.
      14d74e0c
    • Linus Torvalds's avatar
      slub: remove no-longer used 'unlock_out' label · 49a78d08
      Linus Torvalds authored 
      Commit a71ae47a ("slub: Fix double bit unlock in debug mode")
removed the only goto to this label, resulting in

  mm/slub.c: In function '__slab_alloc':
  mm/slub.c:1834: warning: label 'unlock_out' defined but not used

fixed trivially by the removal of the label itself too.
Reported-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      49a78d08
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