Commit Graph

202 Commits

Author SHA1 Message Date
Masami Hiramatsu 7737af010b perf probe: Speed up perf probe --list by caching debuginfo
Speed up the "perf probe --list" by caching the last used debuginfo.
perf probe --list always open and load debuginfo for each entry of probe
list. This takes very a long time.

E.g. with vfs_* events (total 96 probes)

  [root@localhost perf]# time  ./perf probe -l &> /dev/null

  real    0m25.376s
  user    0m24.381s
  sys     0m1.012s

To solve this issue, this adds debuginfo_cache to cache the
last used debuginfo on memory.

With this fix, the perf-probe --list significantly improves
its speed.

  [root@localhost perf]#  time  ./perf probe -l &> /dev/null

  real    0m0.161s
  user    0m0.136s
  sys     0m0.025s

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150617145854.19715.15314.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-17 16:37:53 -03:00
Masami Hiramatsu d350bd571f perf probe: Show usage even if the last event is skipped
When the last part of converted events are blacklisted or out-of-text,
those are skipped and perf probe doesn't show usage examples.  This
fixes it to show the example even if the last part of event list is
skipped.

E.g. without this patch, events are added, but suddenly end:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
    probe:vfs_open       (on vfs_*)
  ...
    probe:vfs_dentry_acceptable (on vfs_*)
    probe:vfs_load_quota_inode (on vfs_*)
  #

With this fix:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
  ...
    probe:vfs_load_quota_inode (on vfs_*)

  You can now use it in all perf tools, such as:

	perf record -e probe:vfs_load_quota_inode -aR sleep 1

Note that this can be reproduced ONLY IF the vfs_caches_init* is the
last part of matched symbol list. I've checked this happens on
"3.19.0-generic #18-Ubuntu" kernel binary.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150616115057.19906.5502.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-17 16:31:42 -03:00
Masami Hiramatsu b031220d52 perf probe: Fix to return error if no probe is added
Fix perf probe to return an error if no probe is added due to the given
probe point being on the blacklist.

To fix this problem, this moves the blacklist checking to right after
finding symbols/probe-points and marks them as skipped.

If all the symbols are skipped, "perf probe"  returns an error as it
fails to find the corresponding probe address.

E.g. currently if a blacklisted probe is given:

  # perf probe do_trap && echo 'succeed'
  Added new event:
  Warning: Skipped probing on blacklisted function: sync_regs
  succeed

No! It must fail! With this patch, it correctly fails:

  # perf probe do_trap && echo 'succeed'
  do_trap is blacklisted function, skip it.
  Probe point 'do_trap' not found.
    Error: Failed to add events.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150616115055.19906.31359.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-16 11:39:51 -03:00
Masami Hiramatsu ba7ecb02e7 perf probe: List probes in stdout
Since commit 5e17b28f1e ("perf probe: Add --quiet option to
suppress output result message") have replaced printf with pr_info,
perf probe -l outputs its result in stderr. However, that is not
what the commit expected.

E.g.:

  # perf probe -l > /dev/null
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)

With this fix:

  # perf probe -l > list
  # cat list
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)

Of course, --quiet(-q) still works on --add/--del.

  # perf probe -q vfs_write
  # perf probe -l
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
    probe:vfs_write      (on vfs_write@ksrc/linux-3/fs/read_write.c)
  -----

Reported-by: Naohiro Aota <naota@elisp.net>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150613013116.24402.2923.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-16 10:34:39 -03:00
Masami Hiramatsu 35a23ff928 perf probe: Cut off the gcc optimization postfixes from function name
Cut off the postfixes which gcc added for optimized routines from the
event name automatically generated from symbol name, since *probe-events
doesn't accept it.  Those symbols will be used if we don't use debuginfo
to find target functions.

E.g. without this fix;
  -----
  # perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf.isra.23 _text+4869328
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  -----
With this fix;
  -----
  perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf _text+4869328
    probe:alloc_buf      (on alloc_buf.isra.23)

  You can now use it in all perf tools, such as:

  	perf record -e probe:alloc_buf -aR sleep 1

  -----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150612050820.20548.41625.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-12 16:14:48 -03:00
Arnaldo Carvalho de Melo 9f2de31542 perf machine: Fix up some more method names
Calling the function 'machine__new_module' implies a new 'module' will
be allocated, when in fact what is returned is a 'struct map' instance,
that not necessarily will be instantiated, as if one already exists with
the given module name, it will be returned instead.

So be consistent with other "find and if not there, create" like
functions, like machine__findnew_thread, machine__findnew_dso, etc, and
rename it to machine__findnew_module_map(), that in turn will call
machine__findnew_module_dso().

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-acv830vd3hwww2ih5vjtbmu3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-08 10:31:34 -03:00
Wang Nan 6bb536cc4b perf probe: Fix segfault when glob matching function without debuginfo
Commit 4c85935122 ("perf probe: Support
glob wildcards for function name") introduces segfault problems when
debuginfo is not available:

 # perf probe 'sys_w*'
  Added new events:
  Segmentation fault

The first problem resides in find_probe_trace_events_from_map(). In
that function, find_probe_functions() is called to match each symbol
against glob to find the number of matching functions, but still use
map__for_each_symbol_by_name() to find 'struct symbol' for matching
functions. Unfortunately, map__for_each_symbol_by_name() does
exact matching by searching in an rbtree.

It doesn't know glob matching, and not easy for it to support it because
it use rbtree based binary search, but we are unable to ensure all names
matched by the glob (any glob passed by user) reside in one subtree.

This patch drops map__for_each_symbol_by_name(). Since there is no
rbtree again, re-matching all symbols costs a lot. This patch avoid it
by saving all matching results into an array (syms).

The second problem is the lost of tp->realname. In
__add_probe_trace_events(), if pev->point.function is glob, the event
name should be set to tev->point.realname. This patch ensures its
existence by strdup sym->name instead of leaving a NULL pointer there.

After this patch:

 # perf probe 'sys_w*'
 Added new events:
   probe:sys_waitid     (on sys_w*)
   probe:sys_wait4      (on sys_w*)
   probe:sys_waitpid    (on sys_w*)
   probe:sys_write      (on sys_w*)
   probe:sys_writev     (on sys_w*)

 You can now use it in all perf tools, such as:

         perf record -e probe:sys_writev -aR sleep 1

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1432892747-232506-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-30 11:08:52 -03:00
Arnaldo Carvalho de Melo 3d39ac5386 perf machine: No need to have two DSOs lists
We can, given a DSO, figure out if it is a kernel, a kernel module or
a userlevel DSO, so stop having to process two lists in several
functions.

If searching becomes an issue at some point, we can have them in a
rbtree, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-s4yb0onpdywu6dj2xl9lxi4t@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-29 12:43:43 -03:00
Wang Nan 60fb774292 perf probe: Fix 'function unused' warning
By 'make build-test' a warning is found in probe-event.c that, after
commit 419e873828 (perf probe: Show the error reason comes from
invalid DSO) the only user of kernel_get_module_dso() is
open_debuginfo(). Which is not compiled if HAVE_DWARF_SUPPORT not set.

'make build-test' found this problem when make_minimal.

This patch moves kernel_get_module_dso() to HAVE_DWARF_SUPPORT ifdef
section.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1432779905-206143-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-29 12:43:39 -03:00
Arnaldo Carvalho de Melo 84c2cafa28 perf tools: Reference count struct map
We have pointers to struct map instances in several places, like in the
hist_entry instances, so we need a way to know when we can destroy them,
otherwise we may either keep leaking them or end up referencing deleted
instances.

Start fixing it by reference counting them.

This patch puts the reference count for struct map in place, replacing
direct map__delete() calls with map__put() ones and then grabbing a
reference count when adding it to the maps struct where maps for a
struct thread are kept.

Next we'll grab reference counts when setting pointers to struct map
instances, in places like in the hist_entry code.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-wi19xczk0t2a41r1i2chuio5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 20:27:30 -03:00
Arnaldo Carvalho de Melo 1eee78aea9 perf tools: Introduce struct maps
That for now has the maps rbtree and the list for the dead maps, that
may be still referenced from some hist_entry, etc.

This paves the way for protecting the rbtree with a lock, then refcount
the maps and finally remove the removed_maps list, as it'll not ne
anymore needed.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-fl0fa6142pj8khj97fow3uw0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 20:21:41 -03:00
Masami Hiramatsu dddc7ee32f perf probe: Fix an error when deleting probes successfully
Fix a bug in del_perf_probe_events() which returns an error (-ENOENT)
even if the probes are successfully deleted.

This happens only if the probes are on user-apps and not on kernel,
simply because it doesn't clear the previous error.

So, without this fix, we get an error even though events are being
successfully removed.

  ------
  # ./perf probe -x ./perf del_perf_probe_events
  Added new event:
    probe_perf:del_perf_probe_events (on del_perf_probe_events in ...

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:del_perf_probe_events -aR sleep 1

  # ./perf probe -d \*:\*
  Removed event: probe_perf:del_perf_probe_events
    Error: Failed to delete events.
  ------

This fixes the above error.
  ------
  # ./perf probe -d \*:\*
  Removed event: probe_perf:del_perf_probe_events
  ------

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Link: http://lkml.kernel.org/r/20150527083725.23880.45209.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:46 -03:00
Masami Hiramatsu 419e873828 perf probe: Show the error reason comes from invalid DSO
Show the reason of error when dso__load* fails. This shows when user
gives wrong kernel image or wrong path.

Without this, perf probe shows an obscure message:

  ----
  $ perf probe -k ~/kbin/linux-3.x86_64/vmlinux -L vfs_read
  Failed to find path of kernel module.
    Error: Failed to show lines.
  ----

With this, perf shows appropriate error message:

  ----
  $ perf probe -k ~/kbin/linux-3.x86_64/vmlinux -L vfs_read
  Failed to find the path for kernel: Mismatching build id
    Error: Failed to show lines.
  ----

And:

  ----
  $ perf probe -k /non-exist/kernel/vmlinux -L vfs_read
  Failed to find the path for kernel: No such file or directory
    Error: Failed to show lines.
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Link: http://lkml.kernel.org/r/20150527083718.23880.84100.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:45 -03:00
Arnaldo Carvalho de Melo 4bb7123dcf perf tools: Use maps__first()/map__next()
In a few more remaining places, for consistency.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-c2n7slwtto29wndfttdrhfrx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:45 -03:00
Arnaldo Carvalho de Melo 614c6b570d perf tools: Leave DSO destruction to the map destruction
As the way DSOs are created are normally via dsos__findnew, so that we
don't have to load the same dso multiple times for multiple maps (think
about /lib64/libc.so.6), so they may be shared and dso__delete() should
be left to be done as part of the map destruction process.

This will all be properly solved by reference counting struct dso, which
will be done soon.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-gbrohe1nvkjxw3u5a1bgj3yh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:45 -03:00
Wang Nan 75e4a2a6af perf probe: Load map before glob matching
Commit 4c85935122 ("perf probe: Support
glob wildcards for function name") introduces a problem:

  # /root/perf probe kmem_cache_free
 Failed to find symbol kmem_cache_free in kernel
   Error: Failed to add events.

The reason is the replacement of map__for_each_symbol_by_name() (by
map__for_each_symbol()). Although their names are similar,
map__for_each_symbol doesn't call map__load() and dso__sort_by_name()
before searching. The missing of map__load() causes this problem because
it search symbol before load dso map.

This patch ensures map__load() is called before using
map__for_each_symbol().

After this patch:

 # /root/perf probe kmem_cache_free
  Added new event:
    probe:kmem_cache_free (on kmem_cache_free%return)

You can now use it in all perf tools, such as:

        perf record -e probe:kmem_cache_free -aR sleep 1

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1431692084-46287-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-18 10:16:48 -03:00
Ingo Molnar f7dc7fd1c0 Merge branch 'perf/urgent' into perf/core, to resolve conflicts
Conflicts:
	tools/perf/builtin-kmem.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-11 11:56:27 +02:00
Masami Hiramatsu 4c85935122 perf probe: Support glob wildcards for function name
Support glob wildcards for function name when adding new probes. This
will allow us to build caches of function-entry level information with
$params.

e.g.
  ----
  # perf probe --no-inlines --add 'kmalloc* $params'
  Added new events:
    probe:kmalloc_slab   (on kmalloc* with $params)
    probe:kmalloc_large_node (on kmalloc* with $params)
    probe:kmalloc_order_trace (on kmalloc* with $params)

  You can now use it in all perf tools, such as:

        perf record -e probe:kmalloc_order_trace -aR sleep 1

  # perf probe --list
    probe:kmalloc_large_node (on kmalloc_large_node@mm/slub.c with size flags node)
    probe:kmalloc_order_trace (on kmalloc_order_trace@mm/slub.c with size flags order)
    probe:kmalloc_slab   (on kmalloc_slab@mm/slab_common.c with size flags)
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150508010335.24812.19972.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:31:02 -03:00
Masami Hiramatsu ddb2f58f9f perf probe: Introduce probe_conf global configs
Introduce probe_conf global configuration parameters for probe-event and
probe-finder, and removes related parameters from APIs.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150508010330.24812.21095.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:26:26 -03:00
Masami Hiramatsu 442255215c perf probe: Use perf_probe_event.target instead of passing as an argument
Use perf_probe_event.target field for the target binary instead of
passing it as an argument.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150508010328.24812.67887.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:25:21 -03:00
Masami Hiramatsu 5a51fcd1f3 perf probe: Skip kernel symbols which is out of .text
Skip the kernel symbols which is out of .text, e.g. the functions
in .inittext. Those are found in debuginfo/kallsyms, but already
freed from memory.

e.g.
  ----
  # perf probe vfs_caches_init
  vfs_caches_init+0 is out of .text, skip it.
  Probe point 'vfs_caches_init' not found.
    Error: Failed to add events.
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150506124649.4961.56249.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:02 -03:00
Masami Hiramatsu 573709fdfd perf probe: Make --line checks validate C-style function name
Fix --line to check valid C-style function name and returns
a semantic error if it is not.

For example, previously, --line doesn't support lazy pattern
but it doesn't recognized as a semantic error.

  ----
  # perf probe -L 'func;return*:0-10'
  Specified source line is not found.
    Error: Failed to show lines.
  ----

With this patch, it is correctly handled as a semantic error.
  ----
  # perf probe -L 'func;return*:0-10'
  Semantic error :'func;return*' is not a valid function name.
  ...
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150506124647.4961.99473.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:02 -03:00
Masami Hiramatsu b8dc3984c1 perf probe: Fix a typo for the flags of open
Fix to pass O_APPEND by using bit-or with other flags, instead of
passing it as mode.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: hemant@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20150506124642.4961.97878.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:01 -03:00
Masami Hiramatsu ae2cb1ac60 perf probe: Fix to close probe_events file in error
Fix perf-probe to close probe_events file if it failed to get existing
probe's name. This also fix the return error code to -ENOMEM.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: hemant@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20150506124640.4961.26062.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:01 -03:00
Masami Hiramatsu 307a464b23 perf probe: Allow to use filter on --del command
This makes perf-probe --del option to accept filter rules
not only simple glob pattern. This simplifies the code and
improve the flexibility.

E.g. if we remove 2 different pattern events, we need 2
     -d options.
  ----
  # ./perf probe -d vfs\* -d malloc
  Removed event: probe_libc:malloc
  Removed event: probe:vfs_read
  ----

  This allows you to joint the 2 patterns with '|'.

  ----
  # ./perf probe -d 'vfs*|malloc'
  Removed event: probe:vfs_read
  Removed event: probe_libc:malloc
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150505022948.23399.4197.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-05 18:13:02 -03:00
Wang Nan e59d29e88f perf probe: Fix segfault if passed with ''.
Since parse_perf_probe_point() deals with a user passed argument, we
should not assume it to be a valid string.

Without this patch, if pass '' to perf probe, a segfault raises:

 $ perf probe -a ''
 Segmentation fault

This patch checks argument of parse_perf_probe_point() before
string processing.

After this patch:

 $ perf probe -a ''

  usage: perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]
     or: perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]
     ...

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1430210769-94177-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-05 12:26:52 -03:00
Masami Hiramatsu b6a896438b perf probe: Accept filter argument for --list
Currently, perf-probe --list option ignores given event filter.
  ----
  # ./perf probe -l vfs\*
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
    probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17.so)
  ----

This changes --list option to accept the event filter argument as below.
  ----
  # ./perf probe -l vfs\*
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
  # ./perf probe -l \*libc:\*
    probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17.so)
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150424094750.23967.53868.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:56 -03:00
Naveen N. Rao 3099c02600 perf probe: Improve detection of file/function name in the probe pattern
Currently, perf probe considers patterns including a '.' to be a file.
However, this causes problems on powerpc ABIv1 where all functions have
a leading '.':

  $ perf probe -F | grep schedule_timeout_interruptible
  .schedule_timeout_interruptible
  $ perf probe .schedule_timeout_interruptible
  Semantic error :File always requires line number or lazy pattern.
    Error: Command Parse Error.

Fix this:
- by checking the probe pattern in more detail, and
- skipping leading dot if one exists when creating/deleting events.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/db680f7cb11c4452b632f908e67151f3aa0f4602.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:53 -03:00
Naveen N. Rao 7b6ff0bdbf perf probe ppc64le: Fixup function entry if using kallsyms lookup
On powerpc ABIv2, if no debug-info is found and we use kallsyms, we need
to fixup the function entry to point to the local entry point. Use
offset of 8 since current toolchains always generate 2 instructions (8
bytes).

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/92253021e77a104b23b615c8c23bf9501dfe60bf.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:47 -03:00
Naveen N. Rao d5c2e2c17a perf probe ppc64le: Prefer symbol table lookup over DWARF
Use symbol table lookups by default if DWARF is not necessary, since
powerpc ABIv2 encodes local entry points in the symbol table and the
function entry address in DWARF may not be appropriate for kprobes, as
described here:

https://sourceware.org/bugzilla/show_bug.cgi?id=17638

"The DWARF address ranges deliberately include the *whole* function,
both global and local entry points."
...
"If you want to set probes on a local entry point, you should look up
the symbol in the main symbol table (not DWARF), and check the st_other
bits; they will indicate whether the function has a local entry point,
and what its offset from the global entry point is.  Note that GDB does
the same when setting a breakpoint on a function entry."

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/88a10e22f4aaba2aef812824ca4b10d7beeea012.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:46 -03:00
Masami Hiramatsu 6dbe31f7ba perf probe: Remove all probes matches given pattern at once
Fix perf-probe --del option to delete all matched probes in both
of kprobes and uprobes at once.

When we have 2 or more events on different binaries as below,

  ----
  # ./perf probe -l
  probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
  probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17
  ----

Trying to remove all event with '*' just removes kprobe events at first.
  ----
  # ./perf probe -d \*
  Removed event: probe:vfs_read
  ----

And in 2nd try, it removes all uprobe events.
  ----
  # ./perf probe -d \*
  Removed event: probe_libc:malloc
  ----

This fixes to remove all event at once as below.
  ----
  # ./perf probe -d \*
  Removed event: probe:vfs_read
  Removed event: probe_libc:malloc
  ----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150423134614.26128.18106.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-29 10:38:03 -03:00
Naohiro Aota 09ed8975c4 perf probe: Find compilation directory path for lazy matching
If we use lazy matching, it failed to open a souce file if perf command
is invoked outside of compilation directory:

$ perf probe -a '__schedule;clear_*'
Failed to open kernel/sched/core.c: No such file or directory
  Error: Failed to add events. (-2)

OTOH, other commands like "probe -L" can solve the souce directory by
themselves. Let's make it possible for lazy matching too!

Signed-off-by: Naohiro Aota <naota@elisp.net>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1426223923-1493-1-git-send-email-naota@elisp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-13 20:11:05 -03:00
He Kuang 9d7b45c572 perf probe: Set retprobe flag when probe in address-based alternative mode
When perf probe searched in a debuginfo file and failed, it tried with
an alternative, in function get_alternative_probe_event():

        memcpy(tmp, &pev->point, sizeof(*tmp));
        memset(&pev->point, 0, sizeof(pev->point));

In this case, it drops the retprobe flag and forgets to set it back in
find_alternative_probe_point(), so the problem occurs.

Can be reproduced as following:

  $ perf probe -v -k vmlinux --add='sys_write%return'
  ...
  Added new event:
  Writing event: p:probe/sys_write _stext+1584952
    probe:sys_write      (on sys_write%return)

  $ cat /sys/kernel/debug/tracing/kprobe_events
  p:probe/sys_write _stext+1584952

After this patch:

  $ perf probe -v -k vmlinux --add='sys_write%return'
  Added new event:
  Writing event: r:probe/sys_write SyS_write+0
    probe:sys_write      (on sys_write%return)

  $ cat /sys/kernel/debug/tracing/kprobe_events
  r:probe/sys_write SyS_write

Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1428925290-5623-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-13 17:25:22 -03:00
Masami Hiramatsu 7afb3fab39 perf probe: Support multiple probes on different binaries
Support multiple probes on different binaries with just
one command.

In the result, this example sets up the probes on icmp_rcv in
kernel, on main and set_target in perf, and on pcspkr_event
in pcspker.ko driver.
  -----
  # perf probe -a icmp_rcv -x ./perf -a main -a set_target \
   -m /lib/modules/4.0.0-rc5+/kernel/drivers/input/misc/pcspkr.ko \
   -a pcspkr_event
  Added new event:
    probe:icmp_rcv       (on icmp_rcv)

  You can now use it in all perf tools, such as:

          perf record -e probe:icmp_rcv -aR sleep 1

  Added new event:
    probe_perf:main      (on main in /home/mhiramat/ksrc/linux-3/tools/perf/perf)

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:main -aR sleep 1

  Added new event:
    probe_perf:set_target (on set_target in /home/mhiramat/ksrc/linux-3/tools/perf/perf)

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:set_target -aR sleep 1

  Added new event:
    probe:pcspkr_event   (on pcspkr_event in pcspkr)

  You can now use it in all perf tools, such as:

          perf record -e probe:pcspkr_event -aR sleep 1
  -----

Reported-by: Arnaldo Carvalho de Melo <acme@infradead.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150401102539.17137.46454.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-10 10:19:53 -03:00
Wang Nan f6c15621f0 perf probe: Fix ARM 32 building error
Commit 9b118acae3 ("perf probe: Fix to
handle aliased symbols in glibc") uses an absolute format '%lx' to
print u64 argument, which causes compiling error on ARM 32.

This patch replaces it with PRIx64.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1428459274-138470-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08 10:49:48 -03:00
Wang Nan ba92732e98 perf kmaps: Check kmaps to make code more robust
This patch add checks in places where map__kmap is used to get kmaps
from struct kmap.

Error messages are added at map__kmap to warn invalid accessing of kmap
(for the case of !map->dso->kernel, kmap(map) does not exists at all).

Also, introduces map__kmaps() to warn uninitialized kmaps.

Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1428394966-131044-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08 09:07:03 -03:00
Masami Hiramatsu e6d7c91c8c perf probe: Fix to get ummapped symbol address on kernel
Fix to get correctly unmapped symbol address on kernel.  This allows us
to probe on syscall symbols which are aliases of SyS_ functions with
using debuginfo.

Without this fix:
  ----
  # ./perf probe -a sys_write
  Failed to find debug information for address 3b0100
  Probe point 'sys_write' not found.
    Error: Failed to add events.
  ----
The address 0x3b0100 is a mapped address, and not usable
in debuginfo.

With this fix:
  ----
  # ./perf probe -a sys_write
  Added new event:
    probe:sys_write      (on sys_write)

  You can now use it in all perf tools, such as:

          perf record -e probe:sys_write -aR sleep 1
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150322114022.32639.19096.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-24 12:07:04 -03:00
He Kuang 0560a0c4a1 perf probe: Fix failure to add multiple probes without debuginfo
Perf tries to find probe function addresses from map when debuginfo
could not be found.

To the first added function, the value of ref_reloc_sym was set in
maps__set_kallsyms_ref_reloc_sym() and can be obtained from
host_machine->kmaps->maps. After that, new maps are added to
host_machine->kmaps->maps in dso__load_kcore(), all these new added maps
do not have a valid ref_reloc_sym.

When adding a second function, get_target_map() may get a map without
valid ref_reloc_sym, and raise the error "Relocated base symbol is not
found".

Fix this by using kernel_get_ref_reloc_sym() to get ref_reloc_sym.

This problem can be reproduced as following:

  $ perf probe --add='sys_write' --add='sys_open'
  Relocated base symbol is not found!
    Error: Failed to add events.

After this patch:

  $ perf probe --add='sys_write' --add='sys_open'
  Added new event:
    probe:sys_write      (on sys_write)

  You can now use it in all perf tools, such as:

      perf record -e probe:sys_write -aR sleep 1

  Added new event:
    probe:sys_open       (on sys_open)

  You can now use it in all perf tools, such as:

      perf record -e probe:sys_open -aR sleep 1

Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1426816616-2394-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-21 14:53:21 -03:00
David Ahern 6d4a48968b perf probe: Fix compiles due to declarations using perf_probe_point
perf fails to build with gcc "(GCC) 4.4.7 20120313 (Red Hat
4.4.7-4.0.9)" (a.k.a., RHEL6 / CentOS 6 / OL 6):

  cc1: warnings being treated as errors
  util/probe-event.c: In function ‘get_alternative_line_range’:
  util/probe-event.c:359: error: missing initializer
  util/probe-event.c:359: error: (near initialization for ‘pp.file’)
  util/probe-event.c:359: error: missing initializer
  util/probe-event.c:359: error: (near initialization for ‘result.function’)

Fix by bringing in initializers to declaration.

Signed-off-by: David Ahern <david.ahern@oracle.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/1426084580-60780-1-git-send-email-david.ahern@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:40:00 -03:00
He Kuang a78604deff perf probe: Fix possible double free on error
A double free occurred when get source file path failed. If lr->path
failed to assign a new value, it will be freed as the old path and then
be freed again during line_range__clear(), and causes this:

  $ perf probe -L do_execve -k vmlinux
  *** Error in `/usr/bin/perf': double free or corruption (fasttop):
      0x0000000000a9ac50 ***
  ======= Backtrace: =========
  ../lib64/libc.so.6(+0x6eeef)[0x7ffff5e44eef]
  ../lib64/libc.so.6(+0x78cae)[0x7ffff5e4ecae]
  ../lib64/libc.so.6(+0x79987)[0x7ffff5e4f987]
  ../bin/perf[0x4ab41f]
  ...

This patch fix this problem.

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1425463302-1687-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:58 -03:00
Namhyung Kim e578da3b20 perf probe: Allow weak symbols to be probed
It currently prevents adding probes in weak symbols.  But there're cases
that given name is an only weak symbol so that we cannot add probe.

  $ perf probe -x /usr/lib/libc.so.6 -a calloc
  Failed to find symbol calloc in /usr/lib/libc-2.21.so
    Error: Failed to add events.

  $ nm /usr/lib/libc.so.6 | grep calloc
  000000000007b1f0 t __calloc
  000000000007b1f0 T __libc_calloc
  000000000007b1f0 W calloc

This change will result in duplicate probes when strong and weak symbols
co-exist in a binary.  But I think it's not a big problem since probes
at the weak symbol will never be hit anyway.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073129.6904.41078.stgit@localhost.localdomain
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:55 -03:00
Namhyung Kim 680d926a8c perf symbols: Allow symbol alias when loading map for symbol name
When perf probe tries to add a probe in a binary using symbol name, it
sometimes failed since some symbols were discard during loading dso.

When it resolves an address to symbol, it'd be better to have just one
symbol at given address.  But for finding address from symbol, it'd be
better to keep all names (including aliases).

So allow tools to state that they want to allow aliases via
symbol_conf.allow_aliases.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073127.6904.3232.stgit@localhost.localdomain
[ Original patch passwd allow_alias to many functions, use symbol_conf.allow_aliases instead ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:54 -03:00
Masami Hiramatsu 0687eba787 Revert "perf probe: Fix to fall back to find probe point in symbols"
This reverts commit 906451b98b ("perf probe: Fix to fall back to find probe point in symbols").

Since 'perf probe' now retries with the address of given symbol searched from
map before this path, this fall back routine isn't needed anymore.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073124.6904.1751.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:53 -03:00
Masami Hiramatsu 811dd2ae7c perf probe: Fix --line to handle aliased symbols in glibc
Fix perf probe --line to handle aliased symbols correctly in glibc.

This makes line_range search failing back to address-based alternative
search as same as --add and --vars.

Without this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -L malloc
  Specified source line is not found.
    Error: Failed to show lines.
  -----

With this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -L malloc
  <__libc_malloc@/usr/src/debug/glibc-2.17-c758a686/malloc/malloc.c:0>
        0  __libc_malloc(size_t bytes)
        1  {
             mstate ar_ptr;
             void *victim;

             __malloc_ptr_t (*hook) (size_t, const __malloc_ptr_t)
        6      = force_reg (__malloc_hook);
        7    if (__builtin_expect (hook != NULL, 0))
        8      return (*hook)(bytes, RETURN_ADDRESS (0));

       10    arena_lookup(ar_ptr);

       12    arena_lock(ar_ptr, bytes);
  -----

Note that this actually shows __libc_malloc, since it is the real
instance of malloc. User can use both __libc_malloc and malloc for
--line.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073122.6904.18540.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:53 -03:00
Masami Hiramatsu 9b118acae3 perf probe: Fix to handle aliased symbols in glibc
Fix perf probe to handle aliased symbols correctly in glibc.  In the
glibc, several symbols are defined as an alias of __libc_XXX, e.g.
malloc is an alias of __libc_malloc.

In such cases, dwarf has no subroutine instances of the alias functions
(e.g. no "malloc" instance), but the map has that symbol and its
address.

Thus, if we search the alieased symbol in debuginfo, we always fail to
find it, but it is in the map.

To solve this problem, this fails back to address-based alternative
search, which searches the symbol in the map, translates its address to
alternative (correct) function name by using debuginfo, and retry to
find the alternative function point from debuginfo.

This adds fail-back process to --vars, --lines and --add options. So,
now you can use those on malloc@libc :)

Without this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -V malloc
  Failed to find the address of malloc
    Error: Failed to show vars.
  # ./perf probe -x /usr/lib64/libc-2.17.so -a "malloc bytes"
  Probe point 'malloc' not found in debuginfo.
    Error: Failed to add events.
  -----

With this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -V malloc
  Available variables at malloc
          @<__libc_malloc+0>
                  size_t  bytes
  # ./perf probe -x /usr/lib64/libc-2.17.so -a "malloc bytes"
  Added new event:
    probe_libc:malloc    (on malloc in /usr/lib64/libc-2.17.so with bytes)

  You can now use it in all perf tools, such as:

          perf record -e probe_libc:malloc -aR sleep 1
  -----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073120.6904.13779.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:52 -03:00
Masami Hiramatsu 79702f6141 perf probe: Warn if given uprobe event accesses memory on older kernel
Warn if given uprobe event accesses memory on older kernel.

Until 3.14, uprobe event only supports accessing registers so this warns
to upgrade kernel if uprobe-event returns -EINVAL and an argument of the
event accesses memory ($stack, @+offset, and +|-offs() symtax).

With this patch (on 3.10.0-123.13.2.el7.x86_64);
  -----
  # ./perf probe -x ./perf warn_uprobe_event_compat stack=-0\(%sp\)
  Added new event:
  Failed to write event: Invalid argument
  Please upgrade your kernel to at least 3.14 to have access to feature -0(%sp)
    Error: Failed to add events.
  -----

Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20150228025329.32106.70581.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-02 12:27:43 -03:00
He Kuang f56847c2e9 perf probe: Fix a precedence bug
The minus operator has higher precedence than ?: Add parentheses around
?: fix this.

Before this patch:

  $ echo 'p:myprobe do_sys_open' > /sys/kernel/debug/tracing/kprobe_events
  $ perf probe -l -k ../vmlinux
    kprobes:myprobe      (on do_sys_open)

After this patch:

  $ echo 'p:myprobe do_sys_open' > /sys/kernel/debug/tracing/kprobe_events
  $ perf probe -l -k ../vmlinux
    kprobes:myprobe      (on do_sys_open@linux.git/fs/open.c)

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1425034373-14511-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-27 10:31:09 -03:00
Arnaldo Carvalho de Melo 38ae502b1d perf probe: Handle strdup() failure
We could end up returning 0 (Ok) with a NULL raw_path. Fix it.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Link: http://lkml.kernel.org/n/tip-l0kcbcg5f4nnzqt01cv42vec@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-27 10:08:29 -03:00
Masami Hiramatsu eb47cb2eb2 perf probe: Fix get_real_path to free allocated memory in error path
Fix get_real_path to free allocated memory when comp_dir is used for
complementing path and getting an error.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150226082504.28125.74506.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-26 11:59:05 -03:00
Masami Hiramatsu 9aaf5a5f47 perf probe: Check kprobes blacklist when adding new events
Recent linux kernel provides a blacklist of the functions which can not
be probed. perf probe can now check this blacklist before setting new
events and indicate better error message for users.

Without this patch,
  ----
  # perf probe --add vmalloc_fault
  Added new event:
  Failed to write event: Invalid argument
    Error: Failed to add events.
  ----
With this patch
  ----
  # perf probe --add vmalloc_fault
  Added new event:
  Warning: Skipped probing on blacklisted function: vmalloc_fault
  ----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150219143113.14434.5387.stgit@localhost.localdomain
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-26 11:59:05 -03:00