Commit Graph

385 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo ee51d85139 perf annotate: Introduce strerror for handling symbol__disassemble() errors
We were just using pr_error() which makes it difficult for non stdio UIs
to provide errors using its widgets, as they need to somehow catch what
was passed to pr_error().

Fix it by introducing a __strerror() interface like the ones used
elsewhere, for instance target__strerror().

This is just the initial step, more work will be done, but first some
error handling bugs noticed while working on this need to be dealt with.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-dgd22zl2xg7x4vcnoa83jxfb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-01 18:18:16 -03:00
Arnaldo Carvalho de Melo 5cb725a972 perf annotate: Rename symbol__annotate() to symbol__disassemble()
This function will not annotate anything, it will just disassembly the
given map->dso and symbol.

It currently does this by parsing the output of 'objdump --disassemble',
but this could conceivably be done using a library or an offshot of
the kernel's instruction decoder (arch/x86/lib/inat.c), etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2xpfl4bfnrd6x584b390qok7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-01 17:06:46 -03:00
Arnaldo Carvalho de Melo c8b5f2c96d tools: Introduce str_error_r()
The tools so far have been using the strerror_r() GNU variant, that
returns a string, be it the buffer passed or something else.

But that, besides being tricky in cases where we expect that the
function using strerror_r() returns the error formatted in a provided
buffer (we have to check if it returned something else and copy that
instead), breaks the build on systems not using glibc, like Alpine
Linux, where musl libc is used.

So, introduce yet another wrapper, str_error_r(), that has the GNU
interface, but uses the portable XSI variant of strerror_r(), so that
users rest asured that the provided buffer is used and it is what is
returned.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-12 15:19:47 -03:00
Arnaldo Carvalho de Melo e5cadb93d0 perf evlist: Rename for_each() macros to for_each_entry()
To match the semantics for list.h in the kernel, that are used to
implement those macros.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-qbcjlgj0ffxquxscahbpddi3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-23 11:26:15 -03:00
Taeung Song 41840d211c perf config: Move config declarations from util/cache.h to util/config.h
Lately util/config.h has been added but util/cache.h has declarations of
functions and a global variable for config features.

To manage codes about configuration at one spot, move them to
util/config.h and let source files that need config features include
config.h And if the source files that included previous cache.h need
only config.h, remove including cache.h.

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1466672119-4852-2-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-23 08:51:41 -03:00
Jiri Olsa d05e3aaeea perf stdio: Add use_callchain parameter to hists__fprintf
It will be convenient in following patches to display hists entries
without callchains even if they are defined.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1465928361-2442-9-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-15 10:48:02 -03:00
Arnaldo Carvalho de Melo e77a07425f perf top: Use machine->kptr_restrict_warned
Its now there, no need to have it too.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-y18oeou494uy11im7u9to0dx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-20 11:43:55 -03:00
Jiri Olsa 35a634f76c perf hists: Move sort__has_socket into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_socket into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-6-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:01 -03:00
Jiri Olsa 2e0453af4e perf hists: Move sort__has_sym into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_sym into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-4-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:59 -03:00
Jiri Olsa 52225036fa perf hists: Move sort__need_collapse into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__need_collapse into struct perf_hpp_list.

Adding hists__has macro to easily access this info perf struct hists
object.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:58 -03:00
Arnaldo Carvalho de Melo 4cb93446c5 perf tools: Set the maximum allowed stack from /proc/sys/kernel/perf_event_max_stack
There is an upper limit to what tooling considers a valid callchain,
and it was tied to the hardcoded value in the kernel,
PERF_MAX_STACK_DEPTH (127), now that this can be tuned via a sysctl,
make it read it and use that as the upper limit, falling back to
PERF_MAX_STACK_DEPTH for kernels where this sysctl isn't present.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-yjqsd30nnkogvj5oyx9ghir9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-27 10:29:07 -03:00
Arnaldo Carvalho de Melo e3815264a6 perf top: Use callchain_param.enabled instead of symbol_conf.use_callchain
One more step in the direction of using just callchain_param for
callchain parameters.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-3b1o9kb2dc94zldz0klckti6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-18 12:30:16 -03:00
Arnaldo Carvalho de Melo 2ddd5c049e perf tools: Ditch record_opts.callgraph_set
We have callchain_param.enabled for that.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-silwqjc2t25ls42dsvg28pp5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-18 12:26:27 -03:00
Arnaldo Carvalho de Melo e68ae9cf7d perf evsel: Do not use globals in config()
Instead receive a callchain_param pointer to configure callchain
aspects, not doing so if NULL is passed.

This will allow fine grained control over which evsels in an evlist
gets callchains enabled.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2mupip6khc92mh5x4nw9to82@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-11 22:18:20 -03:00
Arnaldo Carvalho de Melo 531d241063 perf tools: Do not include stringify.h from the kernel sources
Use instead the copy just made to tools/include/linux/.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-q736w12nwy98x5ox2hamp5ow@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-03-23 15:21:15 -03:00
Arnaldo Carvalho de Melo bb3eb56622 perf machine: Rename perf_event__preprocess_sample to machine__resolve
Since we only deal with fields in the passed struct perf_sample move
this method to struct machine, that is where the perf_sample fields
will be resolved to a struct addr_location, i.e. thread, map, symbol,
etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-a1ww2lbm2vbuqsv4p7ilubu9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-03-23 12:03:08 -03:00
Arnaldo Carvalho de Melo 473398a21d perf tools: Add cpumode to struct perf_sample
To avoid parsing event->header.misc in many locations.

This will also allow setting perf.sample.{ip,cpumode} in a single place,
from tracepoint fields, as needed by 'perf kvm' with PPC guests, where
the guest hardware counters is not available at the host.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-qp3yradhyt6q3wl895b1aat0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-03-23 12:03:07 -03:00
Wang Nan b8cbb34906 perf config: Bring perf_default_config to the very beginning at main()
Before this patch each subcommand calls perf_config() by themself,
reading the default configuration together with subcommand specific
options. If a subcommand doesn't have it own options, it needs to call
'perf_config(perf_default_config, NULL)' to ensure .perfconfig is
loaded.

This patch brings perf_config(perf_default_config, NULL) to the very
start of main(), so subcommands don't need to do it.

After this patch, 'llvm.clang-path' works for 'perf trace'.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456479154-136027-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-26 19:49:16 -03:00
Namhyung Kim c92fcfde34 perf top: Add --hierarchy option
Support hierarchy output for perf-top using --hierarchy option.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1456326830-30456-19-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 20:21:15 -03:00
Arnaldo Carvalho de Melo 3ee60c3b18 perf top: Move UI initialization ahead of sort setup
The ui initialization changes hpp format callbacks, based on the used
browser. Thus we need this init being processed before setup_sorting.

Replica of a patch by Jiri for 'perf report'.

Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1453109064-1026-9-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-03 12:24:03 -03:00
Jiri Olsa 452ce03b1e perf hists: Introduce perf_evsel__output_resort function
Adding evsel specific function to sort hists_evsel based hists. The
hists__output_resort can be now used to sort common hists object.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1453109064-1026-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-03 11:13:11 -03:00
Namhyung Kim 053a3989e1 perf report/top: Add --raw-trace option
The --raw-trace option allows disabling pretty printing by the event's
print_fmt or plugin.  Besides that, each dynamic sort key now can
receive a 'raw' suffix separated by '/' to ask for the raw trace of a
specific field.

  $ perf report -s comm,kmem:kmalloc.gfp_flags
  ...
  # Overhead  Command            gfp_flags
  # ........  .......  ...................
  #
      99.89%  perf       GFP_NOFS|GFP_ZERO
       0.06%  sleep             GFP_KERNEL
       0.03%  perf     GFP_KERNEL|GFP_ZERO
       0.01%  perf              GFP_KERNEL

Now

  $ perf report -s comm,kmem:kmalloc.gfp_flags --raw-trace
or
  $ perf report -s comm,kmem:kmalloc.gfp_flags/raw
  ...
  # Overhead  Command   gfp_flags
  # ........  .......  ..........
  #
      99.89%  perf          32848
       0.06%  sleep           208
       0.03%  perf          32976
       0.01%  perf            208

Suggested-and-Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-9-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-01-06 20:11:12 -03:00
Namhyung Kim 40184c46a3 perf tools: Pass evlist to setup_sorting()
This is a preparation to support dynamic sort keys for tracepoint
events.  Dynamic sort keys can be created for specific fields in trace
events so it needs the event information.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-5-git-send-email-namhyung@kernel.org
[ Moving the evlist creation earlier in top was split to a previous patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-01-06 20:11:11 -03:00
Namhyung Kim 54f8f40384 perf top: Create the evlist sooner
This is a preparation to support dynamic sort keys for tracepoint
events.  Dynamic sort keys can be created for specific fields in trace
events so it needs the event information, so we need to pass the evlist
to the sort routines, create it sooner so that the next patch can do
that.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-5-git-send-email-namhyung@kernel.org
[ Split from the patch passing the evlist to the sort routines ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-01-06 20:11:11 -03:00
Josh Poimboeuf 4b6ab94eab perf subcmd: Create subcmd library
Move the subcommand-related files from perf to a new library named
libsubcmd.a.

Since we're moving files anyway, go ahead and rename 'exec_cmd.*' to
'exec-cmd.*' to be consistent with the naming of all the other files.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.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/c0a838d4c878ab17fee50998811612b2281355c1.1450193761.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-17 14:27:14 -03:00
Namhyung Kim beefb8d0e5 perf top: Cleanup condition in perf_top__record_precise_ip()
The 'he' cannot be NULL since it's caller hist_iter__top_callback() is
called only if iter->he is not NULL (see hist_entry_iter__add).  So
setting 'sym' before the condition to simplify the code.

Also make it clearer that the top->symbol_filter_entry check is only
meaningful on stdio mode (i.e. when use_browser is 0).

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1449802616-16170-4-git-send-email-namhyung@kernel.org
[ Complete the simplification replacing one more he->ms.sym with sym ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-11 08:38:10 -03:00
Namhyung Kim 448f13b2d1 perf top: Fix annotation on --stdio
The ui__has_annotation() inside perf_top__record_precise_ip() should be
removed since it returns true only for TUI (and when sort key has
symbol).  However the 'perf top --stdio' also supports annotation for a
symbol which was specified by 's' key action.

Actually it already does the necessary checks before calling the
function.  So it's ok to get rid of the check here.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1449802616-16170-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-11 08:36:18 -03:00
Namhyung Kim 151ee834cc perf top: Access hists->lock only if needed
The perf_top__record_precise_ip() releases and regrabs the
he->hists->lock because it can sleep if there's an error.  But it should
be done conditionally as it slows down the fast path.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1449802616-16170-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-11 08:34:49 -03:00
Namhyung Kim 64226bcf64 perf top: Do not convert address for perf_top__record_precise_ip()
We call map->unmap_ip() before the function and call map->map_ip()
inside the function.  This is meaningless and look strange since only
one of the two checks 'map'.  Let's use al->addr directly.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1449802616-16170-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-11 08:33:18 -03:00
Masami Hiramatsu 9d8b172f29 perf tools: Make perf_session__register_idle_thread drop the refcount
Note that since the thread was already inserted to the session
list, it will be released when the session is released.
Also, in perf_session__register_idle_thread() failure path,
the thread should be put before returning.

Refcnt debugger shows that the perf_session__register_idle_thread
gets the returned thread, but the caller (__cmd_top) does not
put the returned idle thread.

  ----
  ==== [0] ====
  Unreclaimed thread@0x24e6240
  Refcount +1 => 0 at
    ./perf(thread__new+0xe5) [0x4c8a75]
    ./perf(machine__findnew_thread+0x9a) [0x4bbdba]
    ./perf(perf_session__register_idle_thread+0x28) [0x4c63c8]
    ./perf(cmd_top+0xd7d) [0x43cf6d]
    ./perf() [0x47ba35]
    ./perf(main+0x617) [0x4225b7]
    /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f06027c5af5]
    ./perf() [0x42272d]
  Refcount +1 => 1 at
    ./perf(thread__get+0x2c) [0x4c8bcc]
    ./perf(machine__findnew_thread+0xee) [0x4bbe0e]
    ./perf(perf_session__register_idle_thread+0x28) [0x4c63c8]
    ./perf(cmd_top+0xd7d) [0x43cf6d]
    ./perf() [0x47ba35]
    ./perf(main+0x617) [0x4225b7]
    /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f06027c5af5]
    ./perf() [0x42272d]
  Refcount +1 => 2 at
    ./perf(thread__get+0x2c) [0x4c8bcc]
    ./perf(machine__findnew_thread+0x112) [0x4bbe32]
    ./perf(perf_session__register_idle_thread+0x28) [0x4c63c8]
    ./perf(cmd_top+0xd7d) [0x43cf6d]
    ./perf() [0x47ba35]
    ./perf(main+0x617) [0x4225b7]
    /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f06027c5af5]
    ./perf() [0x42272d]
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20151209021122.10245.69707.stgit@localhost.localdomain
[ Drop the refcount in perf_session__register_idle_thread() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-10 16:28:58 -03:00
Arnaldo Carvalho de Melo f8a5c0b24b perf top: Do show usage message when failing to create cpu/thread maps
This is necessary to get rid of the browser dependency from
usage_with_options() and its friends.  Because we validate the targets
which are used to create the cpu/thread maps and inform the user about
any override performed via the chosen UI, we don't need to call the
usage routine for that.

Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-slu7lj7buzpwgop1vo9la8ma@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-10 15:47:47 -03:00
Namhyung Kim 76a26549eb perf tools: Improve call graph documents and help messages
The --call-graph option is complex so we should provide better guide for
users.  Also change help message to be consistent with config option
names.  Now perf top will show help like below:

  $ perf top --call-graph
    Error: option `call-graph' requires a value

   Usage: perf top [<options>]

      --call-graph <record_mode[,record_size],print_type,threshold[,print_limit],order,sort_key[,branch]>
           setup and enables call-graph (stack chain/backtrace):

		record_mode:	call graph recording mode (fp|dwarf|lbr)
		record_size:	if record_mode is 'dwarf', max size of stack recording (<bytes>)
				default: 8192 (bytes)
		print_type:	call graph printing style (graph|flat|fractal|none)
		threshold:	minimum call graph inclusion threshold (<percent>)
		print_limit:	maximum number of call graph entry (<number>)
		order:		call graph order (caller|callee)
		sort_key:	call graph sort key (function|address)
		branch:		include last branch info to call graph (branch)

		Default: fp,graph,0.5,caller,function

Requested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1445524112-5201-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-22 16:23:19 -03:00
Namhyung Kim 792aeafa8e perf tools: Defaults to 'caller' callchain order only if --children is enabled
The caller callchain order is useful with --children option since it can
show 'overview' style output, but other commands which don't use
--children feature like 'perf script' or even 'perf report/top' without
--children are better to keep callee order.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1445499946-29817-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-22 15:40:11 -03:00
Namhyung Kim a2c10d39af perf top: Support call-graph display options also
Currently 'perf top --call-graph' option is same as 'perf record'.  But
'perf top' also need to receive display options in 'perf report'.  To do
that, change parse_callchain_report_opt() to allow record options too.

Now perf top can receive display options like below:

  $ perf top --call-graph
    Error: option `call-graph' requires a value

   Usage: perf top [<options>]

        --call-graph
          <mode[,dump_size],output_type,min_percent[,print_limit],call_order[,branch]>
                     setup and enables call-graph (stack chain/backtrace)
                     recording: fp dwarf lbr, output_type (graph, flat,
		     fractal, or none), min percent threshold, optional
		     print limit, callchain order, key (function or
		     address), add branches

  $ perf top --call-graph callee,graph,fp

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1445495330-25416-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-22 15:40:02 -03:00
Namhyung Kim c53d138d41 perf top: Register idle thread
The perf top didn't add the idle/swapper thread to the machine's thread
list and its comm was displayed as ':0'.  Fix it.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1443577526-3240-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-01 09:54:33 -03:00
Namhyung Kim 4b37af5957 perf top: Fix unresolved comm when -s comm is used
The perf top uses 'dso,symbol' sort keys by default so it overlooked a
problem in task's comm resolving.  When the sort key contains 'comm',
some task's comm is not shown properly.  This is because the
perf_top__mmap_read_idx() checks the cpumode value improperly.

The cpumode value of non-sample events are 0 (PERF_RECORD_MISC_CPUMODE_
UNKNOWN) so the events will be ignored by the switch statement.  This patch
allows it for non-sample events.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1443577526-3240-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-01 09:54:33 -03:00
Arnaldo Carvalho de Melo cfc5acd4c8 perf top: Filter symbols based on __map__is_kernel(map)
Instead of using dso->kernel, this is equivalent at the moment,
and helps in reducing the accesses to dso->kernel.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.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>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-1pc2v63iphtifovw3bv0bo1v@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28 15:50:53 -03:00
Kan Liang 2e7ea3ab82 perf tools: Introduce new sort type "socket" for the processor socket
This patch enable perf report to sort by processor socket:

  $ perf report --stdio --sort socket,comm,dso,symbol
  # To display the perf.data header info, please use --header/--header-only options.
  #
  # Total Lost Samples: 0
  #
  # Samples: 686  of event 'cycles'
  # Event count (approx.): 349215462
  #
  # Overhead SOCKET Command Shared Object    Symbol
  # ........ ...... ....... ................ ............................
  #
    97.05%    000   test    test             [.] plusB_c
     0.98%    000   test    test             [.] plusA_c
     0.93%    001   perf    [kernel.vmlinux] [k] smp_call_function_single
     0.19%    001   perf    [kernel.vmlinux] [k] page_fault
     0.19%    001   swapper [kernel.vmlinux] [k] pm_qos_request
     0.16%    000   test    [kernel.vmlinux] [k] add_mm_counter_fast

Signed-off-by: Kan Liang <kan.liang@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1441377946-44429-2-git-send-email-kan.liang@intel.com
[ Fix col calc, un-allcapsify col header & read the topology when not using perf.data ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-14 12:50:30 -03:00
Arnaldo Carvalho de Melo eebd0bfca5 perf env: Rename some leftovers from rename to perf_env
In ce80d3bef9 ("perf tools: Rename perf_session_env to perf_env") we
forgot to rename a few functions to the "perf_env" prefix, do it now.

Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-b3ui3z6ock89z1814pu2er98@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-14 12:50:20 -03:00
Ingo Molnar 40a2ea1bd9 Merge branch 'perf/urgent' into perf/core, to pick up fixes before adding more changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-20 11:48:56 +02:00
Arnaldo Carvalho de Melo 09f4d78ab0 perf top: Show backtrace when handling a SIGSEGV on --stdio mode
It was just freezing instead of informing about the SEGV, fix it and
also print a backtrace, just like in the TUI mode and in 'perf trace'.

Tested by provoking a NULL deref when pressing 'z':

     0.31%  libc-2.20.so     [.] malloc_consolidate
     0.31%  ld-2.20.so       [.] _dl_relocate_object
     0.28%  cc1              [.] ht_lookup
     0.28%  cc1              [.] ira_init_register_move_cost
  perf: Segmentation fault
  Obtained 7 stack frames.
  perf(dump_stack+0x32) [0x4d69f2]
  perf(sighandler_dump_stack+0x29) [0x4d6a89]
  /lib64/libc.so.6(+0x34960) [0x7f5064333960]
  perf() [0x438790]
  /lib64/libpthread.so.0(+0x752a) [0x7f50663dd52a]
  /lib64/libc.so.6(clone+0x6d) [0x7f50643ff22d]
  #

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.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-pewrpzqd29rgmhu2wkk7fhww@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-19 15:16:08 -03:00
Andi Kleen a18b027efe perf top: Add branch annotation code to top
Now that we can process branch data in annotate it makes sense to
support enabling branch recording from top too. Most of the code needed
for this is already in shared code with report. But we need to add:

- The option parsing code (using shared code from the previous patch)
- Document the options
- Set up the IPC/cycles accounting state in the top session
- Call the accounting code in the hist iter callback

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1437233094-12844-8-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-06 16:39:22 -03:00
Namhyung Kim 13d1e536b1 perf top: Move toggling event logic into hists browser
Current 'f' key action to enable/disable events won't work if there're
more than one event since perf_evsel_menu__run() doesn't return the key.
So move it to the hists browser loop so that it can be processed as like
other key action, and it's more natural to handle it there IMHO.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1434858076-6533-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-22 11:21:11 -03:00
Kan Liang 9d9cad763c perf tools: Configurable per thread proc map processing time out
The time out to limit the individual proc map processing was hard code
to 500ms. This patch introduce a new option --proc-map-timeout to make
the time limit configurable.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ying Huang <ying.huang@intel.com>
Link: http://lkml.kernel.org/r/1434549071-25611-2-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-19 18:27:13 -03:00
Arnaldo Carvalho de Melo ae3b6ab603 perf top: Tell the user how to unfreeze events after pressing 'f'
When the user presses 'f' to disable events the visual cues are, well,
the percentages not changing and the number of events freezing.

Be more explicit by changing the help line at the bottom of the screen
to show the following messages when 'f' is pressed:

  "Press 'f' again to re-enable the events"

And then, when 'f' is pressed again:

  "Press 'f' to disable the events or 'h'

Suggested-by: Ingo Molnar <mingo@kernel.org>
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-uhiswg9a9rxm5gxg7ptjskjn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-19 18:13:59 -03:00
Arnaldo Carvalho de Melo fbb7997e30 perf top: Replace CTRL+z with 'f' as hotkey for enable/disable events
I.e. 'freeze'/'unfreeze', this is because CTRL+z has a well known
action, i.e. suspend the app, perf needs to follow that convention, that
will be done on a separate patch, tho.

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-oedcl6ovohara4koig14ayip@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-19 16:56:04 -03:00
Arnaldo Carvalho de Melo 5d484f99ae perf top: Allow disabling/enabling events dynamicly
Now it is possible to press CTRL+z at anytime and that will disable the
events being monitored, essentially turning 'top' into 'report', with
pressing CTRL+z again making it enable the events again, returning to
the 'top' behaviour, i.e. dynamic + decaying of older samples.

One may want, for instance, play with:

    -d, --delay <n>       number of seconds to delay between refreshes

and:

    -z, --zero            zero history across updates

Plus CTRL+z to see only the events since last zeroing, etc.

Suggested-by: Ingo Molnar <mingo@kernel.org>
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-zq7tnh5462blt2yda0bcxh5b@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-17 16:50:52 -03:00
Namhyung Kim 063bd9363b perf hists: Reducing arguments of hist_entry_iter__add()
The evsel and sample arguments are to set iter for later use.  As it
also receives an iter as another argument, just set them before calling
the function.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1432022650-18205-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:43 -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
Arnaldo Carvalho de Melo b91fc39f4a perf machine: Protect the machine->threads with a rwlock
In addition to using refcounts for the struct thread lifetime
management, we need to protect access to machine->threads from
concurrent access.

That happens in 'perf top', where a thread processes events, inserting
and deleting entries from that rb_tree while another thread decays
hist_entries, that end up dropping references and ultimately deleting
threads from the rb_tree and releasing its resources when no further
hist_entry (or other data structures, like in 'perf sched') references
it.

So the rule is the same for refcounts + protected trees in the kernel,
get the tree lock, find object, bump the refcount, drop the tree lock,
return, use object, drop the refcount if no more use of it is needed,
keep it if storing it in some other data structure, drop when releasing
that data structure.

I.e. pair "t = machine__find(new)_thread()" with a "thread__put(t)", and
"perf_event__preprocess_sample(&al)" with "addr_location__put(&al)".

The addr_location__put() one is because as we return references to
several data structures, we may end up adding more reference counting
for the other data structures and then we'll drop it at
addr_location__put() time.

Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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-bs9rt4n0jw3hi9f3zxyy3xln@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:19:27 -03:00