We need to store command names with the pid. Changing map entries to be
a struct holding pid. Process name is coming in shortly.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1435012588-9007-2-git-send-email-jolsa@kernel.org
[ Split providing the set/get accessors from transforming the entries structs ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Instead provide a method to set the array entries, and another to access
the contents.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1435012588-9007-2-git-send-email-jolsa@kernel.org
[ Split providing the set/get accessors from transforming the entries structs ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix failure to probe events on arm, the problem was introduced by commit
5a51fcd1f3 ("perf probe: Skip kernel symbols which is out of .text").
For some architectures, the '_etext' label is not in the .text section
(in the .notes section for arm/arm64). Labels out of the .text section
are not loaded as symbols and we get a zero value when looking up its
addresses, which causes all events to be wrongly skipped.
This patch skips checking the text address range when failing to get the
address of '_etext' and thus fixes the problem.
The problem can be reproduced on arm as follows:
# perf probe --add='generic_perform_write'
generic_perform_write+0 is out of .text, skip it.
Probe point 'generic_perform_write' not found.
Error: Failed to add events.
After this patch:
# perf probe --add='generic_perform_write'
Added new event:
probe:generic_perform_write (on generic_perform_write)
You can now use it in all perf tools, such as:
perf record -e probe:generic_perform_write -aR sleep 1
Signed-off-by: He Kuang <hekuang@huawei.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/1434595750-129791-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When dumping events with 'perf report -D' the event print always starts
with a newline (see dump_event()).
Do the same with the "Aggregated stats" print so that it is not jammed
up against the last event print.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1435045969-15999-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
With 'perf report -D' the PERF_RECORD_FINISHED_ROUND event was printed
without a newline, resulting in:
0x91a18 [0x8]: PERF_RECORD_FINISHED_ROUNDAggregated stats
Other events print their details, but PERF_RECORD_FINISHED_ROUND doesn't
have any so just add a print for a newline.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1435045969-15999-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The Intel events use a dot to separate event name and unit mask. Allow
dot in names in the scanner, and remove special handling of dot as EOF.
Also remove the hack in jevents to replace dot with underscore. This way
dotted events can be specified directly by the user.
I'm not fully sure this change to the scanner is correct (what was the
dot special case good for?), but I haven't found anything that breaks
with it so far at least.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1433921123-25327-8-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Separate the event parsing code in perf_pmu__new_alias() out into a
separate function __perf_pmu__new_alias() so that code can be called
indepdently.
This is based on an earlier patch from Andi Kleen.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1433921123-25327-5-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa pointed out, that the <linux/compiler.h> defines the attribute
'__weak'. We might as well use that.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1433921123-25327-4-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently if we build a single target like:
$ touch util/map.c && make util/map.o
It will not rebuild util/map.o if it already exists and util/map.c is
modified.
The reason is that the top-level 'Makefile' processes util/map.o as an
implicit rule and if util/map.o exists make considers the 'util/map.o'
target as done and will not nest into Makefile.perf.
Adding FORCE for '%', because that's what we want to nest into
Makefile.perf for any target.
Adding Makefile into phony targets, because make tries to rebuild it and
it's also resolved as '%' target.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1434977452-32520-4-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently we test only builds through top level Makefile, but seems like
there's a bunch of users using Makefile.perf directly.
Changing the make suite to be run for Makefile.perf as well. It takes
now considerable amount of time, but hopefully we catch more issues.
Also fixing the output indentation for make_kernelsrc and
make_kernelsrc_tools tests.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1434977452-32520-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
User visible:
- Replace CTRL+z with 'f' as hotkey for enable/disable events (Arnaldo Carvalho de Melo)
- Do not exit when 'f' is pressed in 'report' mode (Arnaldo Carvalho de Melo)
- Tell the user how to unfreeze events after pressing 'f' in 'perf top' (Arnaldo Carvalho de Melo)
- React to unassigned hotkey pressing in 'top/report' (Arnaldo Carvalho de Melo)
- Display total number of samples with --show-total-period in 'annotate' (Martin Liška)
- Add timeout to make procfs mmap processing more robust (Kan Liang)
- Fix sort__sym_cmp to also compare end of symbol (Yannick Brosseau)
Infrastructure:
- Ensure thread-stack is flushed (Adrian Hunter)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Replace CTRL+z with 'f' as hotkey for enable/disable events (Arnaldo Carvalho de Melo)
- Do not exit when 'f' is pressed in 'report' mode (Arnaldo Carvalho de Melo)
- Tell the user how to unfreeze events after pressing 'f' in 'perf top' (Arnaldo Carvalho de Melo)
- React to unassigned hotkey pressing in 'top/report' (Arnaldo Carvalho de Melo)
- Display total number of samples with --show-total-period in 'annotate' (Martin Liška)
- Add timeout to make procfs mmap processing more robust (Kan Liang)
- Fix sort__sym_cmp to also compare end of symbol (Yannick Brosseau)
Infrastructure changes:
- Ensure thread-stack is flushed (Adrian Hunter)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
System wide sampling like 'perf top' or 'perf record -a' read all
threads /proc/xxx/maps before sampling. If there are any threads which
generating a keeping growing huge maps, perf will do infinite loop
during synthesizing. Nothing will be sampled.
This patch fixes this issue by adding per-thread timeout to force stop
this kind of endless proc map processing.
PERF_RECORD_MISC_PROC_MAP_PARSE_TIME_OUT is introduced to indicate that
the mmap record are truncated by time out. User will get warning
notification when truncated mmap records are detected.
Reported-by: Ying Huang <ying.huang@intel.com>
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/1434549071-25611-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When using a map file from a JIT, due to memory reuse, we can obtain
multiple symbols with the same start address but a different length.
The symbols__find does check for the end so not doing it in
sort__sym_cmp was causing the hist_entry in the annotate part of a
report to match to the wrong entry, causing a fatal error.
Signed-off-by: Yannick Brosseau <scientist@fb.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/1434584470-17771-1-git-send-email-scientist@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When that happens we were just ignoring the key press, now this
message is presented in the bottom line (the help line):
"Press '?' for help on key bindings"
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-iyma2j5kj3q9i1stl4mfh90n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
The hists_browser was replacing whatever helpline provided by 'top' or
'report' with a static "Press '?' for help on key bindings", fix it.
Now the message passed by top appears at the bottom of the screen:
"For a higher level overview, try: perf top --sort comm,dso"
As well the message that will be added when the user presses 'f' to
disable the events, something along the lines of "press f again to
re-enable...".
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-dacaja70mbfz3a0yj1n180gx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'f' hotkey is only used when in 'top', dynamic mode, to
enable/disable events, currently not making sense in the 'report',
static mode, where we can't go from showing the histogram entries
created from a perf.data file to adding more events after recreating the
evlist created from the perf.data file, albeit possible, this is not
implemented right now.
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-lholzf472pu98dkkijggwx2m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
To better reflect the purpose of this struct, that is to hold
info about samples, its total number and is percentage.
Cc: Martin Liska <mliska@suse.cz>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-6bf8gwcl975uurl0ttpvtk69@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To compare two records on an instruction base, with --show-total-period
option provided, display total number of samples that belong to a line
in assembly language.
New hot key 't' is introduced for 'perf annotate' TUI.
Signed-off-by: Martin Liska <mliska@suse.cz>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/5583E26D.1040407@suse.cz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The thread-stack represents a thread's current stack. When a thread
exits there can still be many functions on the stack e.g. exit() can be
called many levels deep, so all the callers will never return. To get
that information output, the thread-stack must be flushed.
Previously it was assumed the thread-stack would be flushed when the
struct thread was deleted. With thread ref-counting it is no longer
clear when that will be, if ever. So instead explicitly flush all the
thread-stacks at the end of a session.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1432906425-9911-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
User visible:
- Allow disabling/enabling events dynamicly in 'perf top':
a 'perf top' session can instantly become a 'perf report'
one, i.e. going from dynamic analysis to a static one,
returning to a dynamic one is possible, to toogle the
modes, just press CTRL+z. (Arnaldo Carvalho de Melo)
- Greatly speed up 'perf probe --list' by caching debuginfo
(Masami Hiramatsu)
- Fix 'perf trace' race condition at the end of started
workloads (Sukadev Bhattiprolu)
- Fix a problem when opening old perf.data with different
byte order (Wang Nan)
Infrastructure:
- Ignore .config-detected in .gitignore (Wang Nan)
- Move libtraceevent dynamic list to separated LDFLAGS
variable (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-2' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- List perf probes to stdout. (Masami Hiramatsu)
- Return error when none of the requested probes were
installed. (Masami Hiramatsu)
- Cut off the gcc optimization postfixes from
function name in 'perf probe'. (Masami Hiramatsu)
- Allow disabling/enabling events dynamicly in 'perf top':
a 'perf top' session can instantly become a 'perf report'
one, i.e. going from dynamic analysis to a static one,
returning to a dynamic one is possible, to toogle the
modes, just press CTRL+z. (Arnaldo Carvalho de Melo)
- Greatly speed up 'perf probe --list' by caching debuginfo.
(Masami Hiramatsu)
- Fix 'perf trace' race condition at the end of started
workloads. (Sukadev Bhattiprolu)
- Fix a problem when opening old perf.data with different
byte order. (Wang Nan)
Infrastructure changes:
- Replace map->referenced & maps->removed_maps with
map->refcnt. (Arnaldo Carvalho de Melo)
- Introduce the xyarray__reset() function. (Jiri Olsa)
- Add thread_map__(alloc|realloc)() helpers. (Jiri Olsa)
- Move perf_evsel__(alloc|free|reset)_counts into stat object. (Jiri Olsa)
- Introduce perf_counts__(new|delete|reset)() functions. (Jiri Olsa)
- Ignore .config-detected in .gitignore. (Wang Nan)
- Move libtraceevent dynamic list to separated LDFLAGS
variable. (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
For an upcoming feature in 'perf top' we will have a hotkey to
enable/disable events, so remember if the events in the list are
enabled or disabled and allows toggling this state using a new
method.
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-64c4jvdl5feg2zhimxvokqka@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
I get following crash on multiple systems and across several releases
(at least since v3.18).
Core was generated by `/tmp/perf trace sleep 0.2 '.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 perf_mmap__read_head (mm=0x3fff9bf30070) at util/evlist.h:195
195 u64 head = ACCESS_ONCE(pc->data_head);
(gdb) bt
#0 perf_mmap__read_head (mm=0x3fff9bf30070) at util/evlist.h:195
#1 perf_evlist__mmap_read (evlist=0x10027f11910, idx=<optimized out>)
at util/evlist.c:637
#2 0x000000001003ce4c in trace__run (argv=<optimized out>,
argc=<optimized out>, trace=0x3fffd7b28288) at builtin-trace.c:2259
#3 cmd_trace (argc=<optimized out>, argv=<optimized out>,
prefix=<optimized out>) at builtin-trace.c:2799
#4 0x00000000100657b8 in run_builtin (p=0x10176798 <commands+480>, argc=3,
argv=0x3fffd7b2b550) at perf.c:370
#5 0x00000000100063e8 in handle_internal_command (argv=0x3fffd7b2b550, argc=3)
at perf.c:429
#6 run_argv (argv=0x3fffd7b2af70, argcp=0x3fffd7b2af7c) at perf.c:473
#7 main (argc=3, argv=0x3fffd7b2b550) at perf.c:588
The problem seems to be a race condition, when the application has just
exited. Some/all fds associated with the perf-events (tracepoints) go
into a POLLHUP/ POLLERR state and the mmap region associated with those
events are unmapped (in perf_evlist__filter_pollfd()).
But we go back and do a perf_evlist__mmap_read() which assumes that the
mmaps are still valid and we hit the crash.
If the mapping for an event is released, its refcnt is 0 (and ->base
is NULL), so ensure we have non-zero refcount before accessing the map.
Note that perf-record has a similar logic but unlike perf-trace, the
record__mmap_read_all() checks the evlist->mmap[i].base before accessing
the map.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Zhang <zhlcindy@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20150612060003.GA19913@us.ibm.com
[ Fixed it up to use atomic_read() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
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>
Commit e3d09ec812 ("tools lib traceevent:
Export dynamic symbols used by traceevent plugins") adds libtraceevent
dynamic list directly into LDFLAGS, which makes all targets depend on
that list through LDFLAGS.
This is not good since some of targets like libgtk.so doesn't use plugin
at all, but require the existance of that list because of linker
options.
This patch isolates the -Xlink option into LIBTRACEEVENT_DYNAMIC_LIST_LDFLAGS,
makes only perf and perf.so use it.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.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/1434552389-89144-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Following error occurs when trying to use 'perf report' on x86_64 to
cross analysis a perf.data generated by an old perf on a big-endian
machine:
# perf report
*** Error in `/home/w00229757/perf': free(): invalid next size (fast): 0x00000000032c99f0 ***
======= Backtrace: =========
/lib64/libc.so.6(+0x6eeef)[0x7ff6ff7e2eef]
/lib64/libc.so.6(+0x78cae)[0x7ff6ff7eccae]
/lib64/libc.so.6(+0x79987)[0x7ff6ff7ed987]
/path/to/perf[0x4ac734]
/path/to/perf[0x4ac829]
/path/to/perf(perf_header__process_sections+0x129)[0x4ad2c9]
/path/to/perf(perf_session__read_header+0x2e1)[0x4ad9e1]
/path/to/perf(perf_session__new+0x168)[0x4bd458]
/path/to/perf(cmd_report+0xfa0)[0x43eb70]
/path/to/perf[0x47adc3]
/path/to/perf(main+0x5f6)[0x42fd06]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x7ff6ff795bd5]
/path/to/perf[0x42fe35]
======= Memory map: ========
[SNIP]
The bug is in perf_event__attr_swap(). It swaps all fields in 'struct
perf_event_attr' without checking whether the swapped field exist or
not. In addition, in read_event_desc() allocs memory for attr according
to size read from perf.data.
Therefore, if the perf.data is collected by an old perf (without
aux_watermark, for example), when perf_event__attr_swap() swaping
attr->aux_watermark it destroy malloc's metadata.
This patch introduces boundary checking in perf_event__attr_swap(). It
adds macros bswap_field_64 and bswap_field_32 into
perf_event__attr_swap() to make it only swap exist fields.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.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/1434534999-85347-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit fcfd6611fb ("tools build: Add
detected config support") dynamically creates .config-detected. Add it
to .gitignore.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1434542358-5430-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
When libunwind is on, there is a compile error as :
util/unwind-libunwind.c:363:21: error: 'dso' undeclared (first use in this function)
dso__data_put_fd(dso);
This patch fixes it.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 4bb11d012a ("perf tools: Add dso__data_get/put_fd()")
Link: http://lkml.kernel.org/r/1434453395-10560-1-git-send-email-houpengyang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In order to have 'struct thread_map' allocation on single place and can
change it easily in following patch.
Using alloc|realloc for static helpers, because thread_map__new is
already used in public interface.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1434269985-521-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To zero all the xyarray contents. It will be used in following patches.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1434269985-521-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
'make build-test' finds an error that make_python_perf_so fails due to
missing of libtraceevent-dynamic-list:
'.../python2' util/setup.py \
--quiet build_ext; \
mkdir -p python && \
cp python_ext_build/lib/perf.so python/
/path/to/ld: cannot open linker script file /path/to/kernel/tools/lib/traceevent/libtraceevent-dynamic-list: No such file or directory
collect2: error: ld returned 1 exit status
error: command 'x86_64-linux-gcc' failed with exit status 1
cp: cannot stat 'python_ext_build/lib/perf.so': No such file or directory
make[3]: *** [python/perf.so] Error 1
make[2]: *** [python/perf.so] Error 2
test: test -f ./python/perf.so
make[1]: *** [make_python_perf_so] Error 1
make: *** [build-test] Error 2
make: Leaving directory `/path/to/kernel/tools/perf'
This is caused by commit e3d09ec812
("tools lib traceevent: Export dynamic symbols used by traceevent
plugins") that, it adds the list file to LDFLAGS but forgot to add it to
dependency list of python/perf.so.
This patch fixes this problem.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1434079031-123162-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use just reference counts, so that when no more hist_entry instances
references a map and the thread instance goes away by processing a
PERF_RECORD_EXIT, we can delete the maps.
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-oym7lfhcc7ss6xpz44h7nbxs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
Building perf out of kernel tree is currently broken because the
MANIFEST file refers to kernel files that have been removed. With this
patch make perf-targz-src-pkg succeeds as does building perf using the
generated tarfile.
Signed-off-by: David Ahern <david.ahern@oracle.com>
Link: http://lkml.kernel.org/r/1433526173-172332-1-git-send-email-david.ahern@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Failed in 32bit arch build like this:
CC /opt/h00206996/output/perf/arm32/builtin-record.o
util/session.c: In function ‘perf_session__warn_about_errors’:
util/session.c:1304:9: error: format ‘%lu’ expects argument of type ‘long unsigned int’,
but argument 2 has type ‘long long unsigned int’ [-Werror=format=]
builtin-report.c: In function ‘perf_evlist__tty_browse_hists’:
builtin-report.c:323:2: error: format ‘%lu’ expects argument of type ‘long unsigned int’,
but argument 3 has type ‘u64’ [-Werror=format=]
Replace %lu format strings in warning message with PRIu64 for u64
'total_lost_samples' to fix this problem.
Signed-off-by: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1434026664-71642-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf stat ignores the unsupported event and continue to count supported
event. But if the unsupported event is group leader, perf tool will
crash. After applying this patch, the unsupported group leader will
error out immediately.
Without this patch:
$ perf stat -x, -e '{node-prefetch-refs,cycles}' -- sleep 1
perf: util/evsel.c:1009: get_group_fd: Assertion `!(fd == -1)' failed.
Aborted (core dumped)
With this patch:
$ perf stat -x, -e '{node-prefetch-refs,cycles}' -- sleep 1
Error:
The node-prefetch-refs event is not supported.
Commiter note: Here I got a different output, but no core dump:
[acme@zoo linux]$ perf stat -x, -e '{node-prefetch-refs,cycles}' -- sleep 1
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument)
for event (node-prefetch-refs).
/bin/dmesg may provide additional information.
No CONFIG_PERF_EVENTS=y kernel support configured?
Signed-off-by: Kan Liang <kan.liang@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Link: http://lkml.kernel.org/r/1434004360-8570-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Because there's too many options and I cannot read, I frequently get
confused between -c and -P, and try to do things like:
perf record -P 50000 -- foo
Which does not work; try and make the option description slightly longer
and hopefully less confusing.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150610144850.GP19282@twins.programming.kicks-ass.net
[ Do those changes on the man page as well ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa