Realloc of size zero is a free not an error, avoid this causing a double
free. Caught by clang's address sanitizer:
==2634==ERROR: AddressSanitizer: attempting double-free on 0x6020000015f0 in thread T0:
#0 0x5649659297fd in free llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:123:3
#1 0x5649659e9251 in __zfree tools/lib/zalloc.c:13:2
#2 0x564965c0f92c in mem2node__exit tools/perf/util/mem2node.c:114:2
#3 0x564965a08b4c in perf_c2c__report tools/perf/builtin-c2c.c:2867:2
#4 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10
#5 0x564965944348 in run_builtin tools/perf/perf.c:312:11
#6 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8
#7 0x5649659440c4 in run_argv tools/perf/perf.c:408:2
#8 0x564965942e41 in main tools/perf/perf.c:538:3
0x6020000015f0 is located 0 bytes inside of 1-byte region [0x6020000015f0,0x6020000015f1)
freed by thread T0 here:
#0 0x564965929da3 in realloc third_party/llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x564965c0f55e in mem2node__init tools/perf/util/mem2node.c:97:16
#2 0x564965a08956 in perf_c2c__report tools/perf/builtin-c2c.c:2803:8
#3 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10
#4 0x564965944348 in run_builtin tools/perf/perf.c:312:11
#5 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8
#6 0x5649659440c4 in run_argv tools/perf/perf.c:408:2
#7 0x564965942e41 in main tools/perf/perf.c:538:3
previously allocated by thread T0 here:
#0 0x564965929c42 in calloc third_party/llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0x5649659e9220 in zalloc tools/lib/zalloc.c:8:9
#2 0x564965c0f32d in mem2node__init tools/perf/util/mem2node.c:61:12
#3 0x564965a08956 in perf_c2c__report tools/perf/builtin-c2c.c:2803:8
#4 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10
#5 0x564965944348 in run_builtin tools/perf/perf.c:312:11
#6 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8
#7 0x5649659440c4 in run_argv tools/perf/perf.c:408:2
#8 0x564965942e41 in main tools/perf/perf.c:538:3
v2: add a WARN_ON_ONCE when the free condition arises.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200320182347.87675-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As they are 'struct evsel' methods or related routines, not part of
tools/lib/perf/, aka libperf, to whom the perf_ prefix belongs.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As the "perf_" prefix should be restricted to functions and types in
tools/lib/perf/, aka libperf, this way we reduce a bit the confusion for
types only in libperf or the ones in the more contained tools/perf/
project.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Change Intel PT's branch stack support to use thread stacks. The
advantages of using branch stack support from the thread-stack are:
1. the branches are accumulated separately for each thread
2. the branch stack is cleared only in between continuous traces
This helps pave the way for adding branch stacks to regular events, not
just synthesized events as at present.
While the 2 approaches are not identical, in simple cases the results
can be identical e.g.
Before:
# perf record --kcore -e intel_pt// uname
# perf script --itrace=i10usl -F+brstacksym,+addr,+flags > cmp1.txt
After:
# perf script --itrace=i10usl -F+brstacksym,+addr,+flags > cmp2.txt
# diff -s cmp1.txt cmp2.txt
Files cmp1.txt and cmp2.txt are identical
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Intel PT already has support for creating branch stacks for each context
(per-cpu or per-thread). In the more common per-cpu case, the branch stack
is not separated for different threads, instead being cleared in between
each sample.
That approach will not work very well for adding branch stacks to
regular events. The branch stacks really need to be accumulated
separately for each thread.
As a start to accomplishing that, this patch adds support for putting
branch stack support into the thread-stack. The advantages are:
1. the branches are accumulated separately for each thread
2. the branch stack is cleared only in between continuous traces
This helps pave the way for adding branch stacks to regular events, not
just synthesized events as at present.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Trying to disentangle this a bit further, unfortunately it uses
parse_events(), its interesting to have it separated anyway, so do it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Patch enhances current metric infrastructure to handle "?" in the metric
expression. The "?" can be use for parameters whose value not known
while creating metric events and which can be replace later at runtime
to the proper value. It also add flexibility to create multiple events
out of single metric event added in JSON file.
Patch adds function 'arch_get_runtimeparam' which is a arch specific
function, returns the count of metric events need to be created. By
default it return 1.
This infrastructure needed for hv_24x7 socket/chip level events.
"hv_24x7" chip level events needs specific chip-id to which the data is
requested. Function 'arch_get_runtimeparam' implemented in header.c
which extract number of sockets from sysfs file "sockets" under
"/sys/devices/hv_24x7/interface/".
With this patch basically we are trying to create as many metric events
as define by runtime_param.
For that one loop is added in function 'metricgroup__add_metric', which
create multiple events at run time depend on return value of
'arch_get_runtimeparam' and merge that event in 'group_list'.
To achieve that we are actually passing this parameter value as part of
`expr__find_other` function and changing "?" present in metric
expression with this value.
As in our JSON file, there gonna be single metric event, and out of
which we are creating multiple events.
To understand which data count belongs to which parameter value,
we also printing param value in generic_metric function.
For example,
command:# ./perf stat -M PowerBUS_Frequency -C 0 -I 1000
1.000101867 9,356,933 hv_24x7/pm_pb_cyc,chip=0/ # 2.3 GHz PowerBUS_Frequency_0
1.000101867 9,366,134 hv_24x7/pm_pb_cyc,chip=1/ # 2.3 GHz PowerBUS_Frequency_1
2.000314878 9,365,868 hv_24x7/pm_pb_cyc,chip=0/ # 2.3 GHz PowerBUS_Frequency_0
2.000314878 9,366,092 hv_24x7/pm_pb_cyc,chip=1/ # 2.3 GHz PowerBUS_Frequency_1
So, here _0 and _1 after PowerBUS_Frequency specify parameter value.
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-5-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The synthesize benchmark, run on a single process and thread, shows
perf_event__synthesize_mmap_events as the hottest function with fgets
and sscanf taking the majority of execution time.
fscanf performs similarly well. Replace the scanf call with manual
reading of each field of the /proc/pid/maps line, and remove some
unnecessary buffering.
This change also addresses potential, but unlikely, buffer overruns for
the string values read by scanf.
Performance before is:
$ sudo perf bench internals synthesize -m 16 -M 16 -s -t
\# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 102.810 usec (+- 0.027 usec)
Average num. events: 17.000 (+- 0.000)
Average time per event 6.048 usec
Average data synthesis took: 106.325 usec (+- 0.018 usec)
Average num. events: 89.000 (+- 0.000)
Average time per event 1.195 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 16
Average synthesis took: 68103.100 usec (+- 441.234 usec)
Average num. events: 30703.000 (+- 0.730)
Average time per event 2.218 usec
And after is:
$ sudo perf bench internals synthesize -m 16 -M 16 -s -t
\# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 50.388 usec (+- 0.031 usec)
Average num. events: 17.000 (+- 0.000)
Average time per event 2.964 usec
Average data synthesis took: 52.693 usec (+- 0.020 usec)
Average num. events: 89.000 (+- 0.000)
Average time per event 0.592 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 16
Average synthesis took: 45022.400 usec (+- 552.740 usec)
Average num. events: 30624.200 (+- 10.037)
Average time per event 1.470 usec
On a Intel Xeon 6154 compiling with Debian gcc 9.2.1.
Committer testing:
On a AMD Ryzen 5 3600X 6-Core Processor:
Before:
# perf bench internals synthesize --min-threads 12 --max-threads 12 --st --mt
# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 267.491 usec (+- 0.176 usec)
Average num. events: 56.000 (+- 0.000)
Average time per event 4.777 usec
Average data synthesis took: 277.257 usec (+- 0.169 usec)
Average num. events: 287.000 (+- 0.000)
Average time per event 0.966 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 12
Average synthesis took: 81599.500 usec (+- 346.315 usec)
Average num. events: 36096.100 (+- 2.523)
Average time per event 2.261 usec
#
After:
# perf bench internals synthesize --min-threads 12 --max-threads 12 --st --mt
# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 110.125 usec (+- 0.080 usec)
Average num. events: 56.000 (+- 0.000)
Average time per event 1.967 usec
Average data synthesis took: 118.518 usec (+- 0.057 usec)
Average num. events: 287.000 (+- 0.000)
Average time per event 0.413 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 12
Average synthesis took: 43490.700 usec (+- 284.527 usec)
Average num. events: 37028.500 (+- 0.563)
Average time per event 1.175 usec
#
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200415054050.31645-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To control degree of parallelism of the synthesize_mmap() code which
is scanning /proc/PID/task/PID/maps and can be time consuming.
Mimic perf top way of handling the option.
If not specified will default to 1 thread, i.e. default behavior before
this option.
On a desktop computer the processing of /proc/PID/task/PID/maps isn't
slow enough to warrant parallel processing and the thread creation has
some cost - hence the default of 1. On a loaded server with
>100 cores it is possible to see synthesis times in the order of
seconds and in this case having the option is desirable.
As the processing is a synchronization point, it is legitimate to worry if
Amdahl's law will apply to this patch. Profiling with this patch in
place:
https://lore.kernel.org/lkml/20200415054050.31645-4-irogers@google.com/
shows:
...
- 32.59% __perf_event__synthesize_threads
- 32.54% __event__synthesize_thread
+ 22.13% perf_event__synthesize_mmap_events
+ 6.68% perf_event__get_comm_ids.constprop.0
+ 1.49% process_synthesized_event
+ 1.29% __GI___readdir64
+ 0.60% __opendir
...
That is the processing is 1.49% of execution time and there is plenty to
make parallel. This is shown in the benchmark in this patch:
https://lore.kernel.org/lkml/20200415054050.31645-2-irogers@google.com/
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 1
Average synthesis took: 127729.000 usec (+- 3372.880 usec)
Average num. events: 21548.600 (+- 0.306)
Average time per event 5.927 usec
Number of synthesis threads: 2
Average synthesis took: 88863.500 usec (+- 385.168 usec)
Average num. events: 21552.800 (+- 0.327)
Average time per event 4.123 usec
Number of synthesis threads: 3
Average synthesis took: 83257.400 usec (+- 348.617 usec)
Average num. events: 21553.200 (+- 0.327)
Average time per event 3.863 usec
Number of synthesis threads: 4
Average synthesis took: 75093.000 usec (+- 422.978 usec)
Average num. events: 21554.200 (+- 0.200)
Average time per event 3.484 usec
Number of synthesis threads: 5
Average synthesis took: 64896.600 usec (+- 353.348 usec)
Average num. events: 21558.000 (+- 0.000)
Average time per event 3.010 usec
Number of synthesis threads: 6
Average synthesis took: 59210.200 usec (+- 342.890 usec)
Average num. events: 21560.000 (+- 0.000)
Average time per event 2.746 usec
Number of synthesis threads: 7
Average synthesis took: 54093.900 usec (+- 306.247 usec)
Average num. events: 21562.000 (+- 0.000)
Average time per event 2.509 usec
Number of synthesis threads: 8
Average synthesis took: 48938.700 usec (+- 341.732 usec)
Average num. events: 21564.000 (+- 0.000)
Average time per event 2.269 usec
Where average time per synthesized event goes from 5.927 usec with 1
thread to 2.269 usec with 8. This isn't a linear speed up as not all of
synthesize code has been made parallel. If the synthesis time was about
10 seconds then using 8 threads may bring this down to less than 4.
Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Jones <tonyj@suse.de>
Cc: yuzhoujian <yuzhoujian@didichuxing.com>
Link: http://lore.kernel.org/lkml/20200422155038.9380-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
