The setting and checking of 'done' contains a rare race where the signal
handler setting 'done' is run after checking to break the loop, but
before waiting in evlist__poll(). In this case, the main loop won't wake
up until either another signal is sent, or the perf data fd causes a
wake up.
The following simple script can trigger this condition (but you might
need to run it for several hours):
for ((i = 0; i >= 0; i++)) ; do
echo "Loop $i"
delay=$(echo "scale=4; 0.1 * $RANDOM/32768" | bc)
./perf record -- sleep 30000000 >/dev/null&
pid=$!
sleep $delay
kill -TERM $pid
echo "PID $pid"
wait $pid
done
At some point, the loop will stall. Adding logging, even though perf has
received the SIGTERM and set 'done = 1', perf will remain sleeping until
a second signal is sent.
Committer notes:
Make this dependent on HAVE_EVENTFD_SUPPORT, so that we continue
building on older systems without the eventfd syscall.
Signed-off-by: Anand K Mistry <amistry@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>
Link: http://lore.kernel.org/lkml/20200513122012.v3.1.I4d7421c6bbb1f83ea58419082481082e19097841@changeid
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adrian reported that is_bpf_image is not working the way it was intended
- passing on trampolines and dispatcher names. Instead it returned true
for all the bpf names.
The reason even this logic worked properly is that all bpf objects, even
trampolines and dispatcher, were assigned DSO_BINARY_TYPE__BPF_IMAGE
binary_type.
The later for bpf_prog objects, the binary_type was fixed in bpf load
event processing, which is executed after the ksymbol code.
Fixing the is_bpf_image logic, so it properly recognizes trampoline and
dispatcher objects.
Fixes: 3c29d4483e ("perf annotate: Add basic support for bpf_image")
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200512122310.3154754-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A big uncore event group is split into multiple small groups which only
include the uncore events from the same PMU. This has been supported in
the commit 3cdc5c2cb9 ("perf parse-events: Handle uncore event
aliases in small groups properly").
If the event's PMU name starts to repeat, it must be a new event.
That can be used to distinguish the leader from other members.
But now it only compares the pointer of pmu_name
(leader->pmu_name == evsel->pmu_name).
If we use "perf stat -M LLC_MISSES.PCIE_WRITE -a" on cascadelakex,
the event list is:
evsel->name evsel->pmu_name
---------------------------------------------------------------
unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_4 (as leader)
unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_2
unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_0
unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_5
unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_3
unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_1
unc_iio_data_req_of_cpu.mem_write.part1 uncore_iio_4
......
For the event "unc_iio_data_req_of_cpu.mem_write.part1" with
"uncore_iio_4", it should be the event from PMU "uncore_iio_4".
It's not a new leader for this PMU.
But if we use "(leader->pmu_name == evsel->pmu_name)", the check
would be failed and the event is stored to leaders[] as a new
PMU leader.
So this patch uses strcmp to compare the PMU name between events.
Fixes: d4953f7ef1 ("perf parse-events: Fix 3 use after frees found with clang ASAN")
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200430003618.17002-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Callchains are automatically initialized by checking on event's
sample_type. For pipe mode we need to put this check into attr event
code.
Moving the callchains setup code into callchain_param_setup function and
calling it from attr event process code.
This enables pipe output having callchains, like:
# perf record -g -e 'raw_syscalls:sys_enter' true | perf script
# perf record -g -e 'raw_syscalls:sys_enter' true | perf report
Committer notes:
We still need the next patch for the above output to work.
Reported-by: Paul Khuong <pvk@pvk.ca>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200507095024.2789147-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ian came with the idea of having support to read the pipe data also from
file. Currently pipe mode files fail like:
$ perf record -o - sleep 1 > /tmp/perf.pipe.data
$ perf report -i /tmp/perf.pipe.data
incompatible file format (rerun with -v to learn more)
This patch adds the support to do that by trying the pipe header first,
and if its successfully detected, switching the perf data to pipe mode.
Committer testing:
# ls
# perf record -a -o - sleep 1 > /tmp/perf.pipe.data
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
# ls
# perf report -i /tmp/perf.pipe.data | head -25
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 511 of event 'cycles'
# Event count (approx.): 178447276
#
# Overhead Command Shared Object Symbol
# ........ ........ ................. ...........................................................................................
#
65.49% swapper [kernel.kallsyms] [k] native_safe_halt
6.45% chromium libblink_core.so [.] blink::SelectorChecker::CheckOne
4.08% chromium libblink_core.so [.] blink::SelectorQuery::ExecuteForTraverseRoot<blink::AllElementsSelectorQueryTrait>
2.25% chromium libblink_core.so [.] blink::SelectorQuery::FindTraverseRootsAndExecute<blink::AllElementsSelectorQueryTrait>
2.11% chromium libblink_core.so [.] blink::SelectorChecker::MatchSelector
1.91% chromium libblink_core.so [.] blink::Node::OwnerShadowHost
1.31% chromium libblink_core.so [.] blink::Node::parentNode@plt
1.22% chromium libblink_core.so [.] blink::Node::parentNode
0.59% chromium libblink_core.so [.] blink::AnyAttributeMatches
0.58% chromium libv8.so [.] v8::internal::GlobalHandles::Create
0.58% chromium libblink_core.so [.] blink::NodeTraversal::NextAncestorSibling
0.55% chromium libv8.so [.] v8::internal::RegExpGlobalCache::RegExpGlobalCache
0.55% chromium libblink_core.so [.] blink::Node::ContainingShadowRoot
0.55% chromium libblink_core.so [.] blink::NodeTraversal::NextAncestorSibling@plt
#
Original-patch-by: Ian Rogers <irogers@google.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Khuong <pvk@pvk.ca>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200507095024.2789147-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no need to set 'fd' position in pipe mode, the file descriptor
is already in proper place. Moreover the lseek will fail on pipe
descriptor and that's why it's been working properly.
I was tempted to remove the lseek calls completely, because it seems
that tracing data event was always synthesized only in pipe mode, so
there's no need for 'file' mode handling. But I guess there was a reason
behind this and there might (however unlikely) be a perf.data that we
could break processing for.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Khuong <pvk@pvk.ca>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200507095024.2789147-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When a probe point is expanded to several places (like inlined) and if
some of them are skipped because of blacklisted or __init function,
those trace_events has no event name. It must be skipped while showing
results.
Without this fix, you can see "(null):(null)" on the list,
# ./perf probe request_resource
reserve_setup is out of .text, skip it.
Added new events:
(null):(null) (on request_resource)
probe:request_resource (on request_resource)
You can now use it in all perf tools, such as:
perf record -e probe:request_resource -aR sleep 1
#
With this fix, it is ignored:
# ./perf probe request_resource
reserve_setup is out of .text, skip it.
Added new events:
probe:request_resource (on request_resource)
You can now use it in all perf tools, such as:
perf record -e probe:request_resource -aR sleep 1
#
Fixes: 5a51fcd1f3 ("perf probe: Skip kernel symbols which is out of .text")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763968263.30755.12800484151476026340.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since commit 03db8b583d ("perf tools: Fix
maps__find_symbol_by_name()") introduced map address range check in
maps__find_symbol_by_name(), we can not get "_etext" from kernel map
because _etext is placed on the edge of the kernel .text section (=
kernel map in perf.)
To fix this issue, this checks the address correctness by map address
range information (map->start and map->end) instead of using _etext
address.
This can cause an error if the target inlined function is embedded in
both __init function and normal function.
For exaample, request_resource() is a normal function but also embedded
in __init reserve_setup(). In this case, the probe point in
reserve_setup() must be skipped.
However, without this fix, it failes to setup all probe points:
# ./perf probe -v request_resource
probe-definition(0): request_resource
symbol:request_resource file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
Looking at the vmlinux_path (8 entries long)
Using /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux for symbols
Open Debuginfo file: /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux
Try to find probe point from debuginfo.
Matched function: request_resource [15e29ad]
found inline addr: 0xffffffff82fbf892
Probe point found: reserve_setup+204
found inline addr: 0xffffffff810e9790
Probe point found: request_resource+0
Found 2 probe_trace_events.
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Opening /sys/kernel/debug/tracing//README write=0
Writing event: p:probe/request_resource _text+33290386
Failed to write event: Invalid argument
Error: Failed to add events. Reason: Invalid argument (Code: -22)
#
With this fix,
# ./perf probe request_resource
reserve_setup is out of .text, skip it.
Added new events:
(null):(null) (on request_resource)
probe:request_resource (on request_resource)
You can now use it in all perf tools, such as:
perf record -e probe:request_resource -aR sleep 1
#
Fixes: 03db8b583d ("perf tools: Fix maps__find_symbol_by_name()")
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763967332.30755.4922496724365529088.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix to check kprobe blacklist address correctly with relocated address
by adjusting debuginfo address.
Since the address in the debuginfo is same as objdump, it is different
from relocated kernel address with KASLR. Thus, 'perf probe' always
misses to catch the blacklisted addresses.
Without this patch, 'perf probe' can not detect the blacklist addresses
on a KASLR enabled kernel.
# perf probe kprobe_dispatcher
Failed to write event: Invalid argument
Error: Failed to add events.
#
With this patch, it correctly shows the error message.
# perf probe kprobe_dispatcher
kprobe_dispatcher is blacklisted function, skip it.
Probe point 'kprobe_dispatcher' not found.
Error: Failed to add events.
#
Fixes: 9aaf5a5f47 ("perf probe: Check kprobes blacklist when adding new events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763966411.30755.5882376357738273695.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since the commit 6a13a0d7b4 ("ftrace/kprobe: Show the maxactive number
on kprobe_events") introduced to show the instance number of kretprobe
events, the length of the 1st format of the kprobe event will not 1, but
it can be longer. This caused a parser error in perf-probe.
Skip the length check the 1st format of the kprobe event to accept this
instance number.
Without this fix:
# perf probe -a vfs_read%return
Added new event:
probe:vfs_read__return (on vfs_read%return)
You can now use it in all perf tools, such as:
perf record -e probe:vfs_read__return -aR sleep 1
# perf probe -l
Semantic error :Failed to parse event name: r16:probe/vfs_read__return
Error: Failed to show event list.
And with this fixes:
# perf probe -a vfs_read%return
...
# perf probe -l
probe:vfs_read__return (on vfs_read%return)
Fixes: 6a13a0d7b4 ("ftrace/kprobe: Show the maxactive number on kprobe_events")
Reported-by: Yuxuan Shui <yshuiv7@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Yuxuan Shui <yshuiv7@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207587
Link: http://lore.kernel.org/lkml/158877535215.26469.1113127926699134067.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As all the other tools/perf/scripts/python/bin/*-{report,record}
scripts, fixing the this problem reported by Daniel Diaz:
Our OpenEmbedded builds detected an issue with 5287f92692 ("perf
script: Add flamegraph.py script"):
ERROR: perf-1.0-r9 do_package_qa: QA Issue:
/usr/libexec/perf-core/scripts/python/bin/flamegraph-report contained
in package perf-python requires /usr/bin/sh, but no providers found in
RDEPENDS_perf-python? [file-rdeps]
This means that there is a new binary pulled in in the shebang line
which was unaccounted for: `/usr/bin/sh`. I don't see any other usage
of /usr/bin/sh in the kernel tree (does not even exist on my Ubuntu
dev machine) but plenty of /bin/sh. This patch is needed:
-----8<----------8<----------8<-----
diff --git a/tools/perf/scripts/python/bin/flamegraph-record
b/tools/perf/scripts/python/bin/flamegraph-record
index 725d66e71570..a2f3fa25ef81 100755
--- a/tools/perf/scripts/python/bin/flamegraph-record
+++ b/tools/perf/scripts/python/bin/flamegraph-record
@@ -1,2 +1,2 @@
-#!/usr/bin/sh
+#!/bin/sh
perf record -g "$@"
diff --git a/tools/perf/scripts/python/bin/flamegraph-report
b/tools/perf/scripts/python/bin/flamegraph-report
index b1a79afd903b..b0177355619b 100755
--- a/tools/perf/scripts/python/bin/flamegraph-report
+++ b/tools/perf/scripts/python/bin/flamegraph-report
@@ -1,3 +1,3 @@
-#!/usr/bin/sh
+#!/bin/sh
# description: create flame graphs
perf script -s "$PERF_EXEC_PATH"/scripts/python/flamegraph.py -- "$@"
----->8---------->8---------->8-----
Fixes: 5287f92692 ("perf script: Add flamegraph.py script")
Reported-by: Daniel Díaz <daniel.diaz@linaro.org>
Acked-by: Andreas Gerstmayr <agerstmayr@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: lkft-triage@lists.linaro.org
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/CAEUSe7_wmKS361mKLTB1eYbzYXcKkXdU26BX5BojdKRz8MfPCw@mail.gmail.com
Link: http://lore.kernel.org/lkml/20200505170320.GZ30487@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Running commands
./perf record -e rb0000 -- find .
./perf report -v
reveals symbol names and its addresses. There is a mismatch between
kernel symbol and address. Here is an example for kernel symbol
check_chain_key:
3.55% find /lib/modules/.../build/vmlinux 0xf11ec v [k] check_chain_key
This address is off by 0xff000 as can be seen with:
[root@t35lp46 ~]# fgrep check_chain_key /proc/kallsyms
00000000001f00d0 t check_chain_key
[root@t35lp46 ~]# objdump -t ~/linux/vmlinux| fgrep check_chain_key
00000000001f00d0 l F .text 00000000000001e8 check_chain_key
[root@t35lp46 ~]#
This function is located in main memory 0x1f00d0 - 0x1f02b4. It has
several entries in the perf data file with the correct address:
[root@t35lp46 perf]# ./perf report -D -i perf.data.find-bad | \
fgrep SAMPLE| fgrep 0x1f01ec
PERF_RECORD_SAMPLE(IP, 0x1): 22228/22228: 0x1f01ec period: 1300000 addr: 0
PERF_RECORD_SAMPLE(IP, 0x1): 22228/22228: 0x1f01ec period: 1300000 addr: 0
The root cause happens when reading symbol tables during perf report.
A long gdb call chain leads to
machine__deliver_events
perf_evlist__deliver_event
perf_evlist__deliver_sample
build_id__mark_dso_hits
thread__find_map(1) Read correct address from sample entry
map__load
dso__load Some more functions to end up in
....
dso__load_sym.
Function dso__load_syms checks for kernel relocation and symbol
adjustment for the kernel and results in kernel map adjustment of
kernel .text segment address (0x100000 on s390)
kernel .text segment offset in file (0x1000 on s390).
This results in all kernel symbol addresses to be changed by subtracting
0xff000 (on s390). For the symbol check_chain_key we end up with
0x1f00d0 - 0x100000 + 0x1000 = 0xf11d0
and this address is saved in the perf symbol table. This calculation is
also applied by the mapping functions map__mapip() and map__unmapip()
to map IP addresses to dso mappings.
During perf report processing functions
process_sample_event (builtin-report.c)
machine__resolve
thread__find_map
hist_entry_iter_add
are called. Function thread__find_map(1)
takes the correct sample address and applies the mapping function
map__mapip() from the kernel dso and saves the modified address
in struct addr_location for further reference. From now on this address
is used.
Funktion process_sample_event() then calls hist_entry_iter_add() to save
the address in member ip of struct hist_entry.
When samples are displayed using
perf_evlist__tty_browse_hists
hists__fprintf
hist_entry__fprintf
hist_entry__snprintf
__hist_entry__snprintf
_hist_entry__sym_snprintf()
This simply displays the address of the symbol and ignores the dso <-> map
mappings done in function thread__find_map. This leads to the address
mismatch.
Output before:
ot@t35lp46 perf]# ./perf report -v | fgrep check_chain_key
3.55% find /lib/modules/5.6.0d-perf+/build/vmlinux
0xf11ec v [k] check_chain_key
[root@t35lp46 perf]#
Output after:
[root@t35lp46 perf]# ./perf report -v | fgrep check_chain_key
3.55% find /lib/modules/5.6.0d-perf+/build/vmlinux
0x1f01ec v [k] check_chain_key
[root@t35lp46 perf]#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200415070744.59919-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
