Currently, perf record is broken on arm/arm64 systems when the PMU is
specified explicitly as part of the event, e.g.
$ ./perf record -e armv8_cortex_a53/cpu_cycles/u true
In such cases, perf record fails to open events unless
perf_event_paranoid is set to -1, even if the PMU in question supports
mode exclusion. Further, even when perf_event_paranoid is toggled, no
samples are recorded.
This is an unintended side effect of commit:
e3ba76deef ("perf tools: Force uncore events to system wide monitoring)
... which assumes that if a PMU has an associated cpu_map, it is an
uncore PMU, and forces events for such PMUs to be system-wide.
This is not true for arm/arm64 systems, which can have heterogeneous
CPUs. To account for this, multiple CPU PMUs are exposed, each with a
"cpus" field under sysfs, which the perf tool parses into a cpu_map. ARM
PMUs do not have a "cpumask" file, and only have a "cpus" file. For the
gory details as to why, see commit:
7e3fcffe95 ("perf pmu: Support alternative sysfs cpumask")
Given all of this, we can instead identify uncore PMUs by explicitly
checking for a "cpumask" file, and restore arm/arm64 PMU support back to
a working state. This patch does so, adding a new perf_pmu::is_uncore
field, and splitting the existing cpumask parsing so that it can be
reused.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by Will Deacon <will.deacon@arm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: 4.12+ <stable@vger.kernel.org>
Fixes: e3ba76deef ("perf tools: Force uncore events to system wide monitoring)
Link: http://lkml.kernel.org/r/1507315102-5942-1-git-send-email-mark.rutland@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The build of kernel v4.14-rc1 for i686 fails on RHEL 6 with the error
in tools/perf:
util/syscalltbl.c:157: error: expected ';', ',' or ')' before '__maybe_unused'
mv: cannot stat `util/.syscalltbl.o.tmp': No such file or directory
Fix it by placing/moving:
#include <linux/compiler.h>
outside of #ifdef HAVE_SYSCALL_TABLE block.
Signed-off-by: Akemi Yagi <toracat@elrepo.org>
Cc: Alan Bartlett <ajb@elrepo.org>
Link: http://lkml.kernel.org/r/oq41r8$1v9$1@blaine.gmane.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
With --call-graph option, perf report can display call chains using
type, min percent threshold, optional print limit and order. And the
default call-graph parameter is 'graph,0.5,caller,function,percent'.
Before this patch, 'perf report --call-graph' shows incorrect debug
messages as below:
# perf report --call-graph
Invalid callchain mode: 0.5
Invalid callchain order: 0.5
Invalid callchain sort key: 0.5
Invalid callchain config key: 0.5
Invalid callchain mode: caller
Invalid callchain mode: function
Invalid callchain order: function
Invalid callchain mode: percent
Invalid callchain order: percent
Invalid callchain sort key: percent
That is because in function __parse_callchain_report_opt(),each field of
the call-graph parameter is passed to parse_callchain_{mode,order,
sort_key,value} in turn until it meets the matching value.
For example, the order field "caller" is passed to
parse_callchain_mode() firstly and obviously it doesn't match any mode
field. Therefore parse_callchain_mode() will shows the debug message
"Invalid callchain mode: caller", which could confuse users.
The patch fixes this issue by moving the warning out of the function
parse_callchain_{mode,order,sort_key,value}.
Signed-off-by: Mengting Zhang <zhangmengting@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/1506154694-39691-1-git-send-email-zhangmengting@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Yet another fix for probing the max attr.precise_ip setting: it is not
enough settting attr.exclude_kernel for !root users, as they _can_
profile the kernel if the kernel.perf_event_paranoid sysctl is set to
-1, so check that as well.
Testing it:
As non root:
$ sysctl kernel.perf_event_paranoid
kernel.perf_event_paranoid = 2
$ perf record sleep 1
$ perf evlist -v
cycles:uppp: ..., exclude_kernel: 1, ... precise_ip: 3, ...
Now as non-root, but with kernel.perf_event_paranoid set set to the
most permissive value, -1:
$ sysctl kernel.perf_event_paranoid
kernel.perf_event_paranoid = -1
$ perf record sleep 1
$ perf evlist -v
cycles:ppp: ..., exclude_kernel: 0, ... precise_ip: 3, ...
$
I.e. non-root, default kernel.perf_event_paranoid: :uppp modifier = not allowed to sample the kernel,
non-root, most permissible kernel.perf_event_paranoid: :ppp = allowed to sample the kernel.
In both cases, use the highest available precision: attr.precise_ip = 3.
Reported-and-Tested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: d37a369790 ("perf evsel: Fix attr.exclude_kernel setting for default cycles:p")
Link: http://lkml.kernel.org/n/tip-nj2qkf75xsd6pw6hhjzfqqdx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Peter reported that when he explicitely asked for multiple events with
the same name on the command line it got coalesced into just one line,
i.e.:
# perf stat -e cycles -e cycles -e cycles usleep 1
Performance counter stats for 'usleep 1':
3,269,652 cycles
0.000884123 seconds time elapsed
#
And while there is the --no-merges option to disable that auto-merging,
this is a blunt change in behaviour for such explicit request, so change
the code so that this auto merging is done only when handling the multi
PMU aliases with the same name that introduced this coalescing,
restoring the previous behaviour for the explicit case:
# perf stat -e cycles -e cycles -e cycles usleep 1
Performance counter stats for 'usleep 1':
1,472,837 cycles
1,472,837 cycles
1,472,837 cycles
0.001764870 seconds time elapsed
#
Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 430daf2dc7 ("perf stat: Collapse identically named events")
Link: http://lkml.kernel.org/r/20170831184122.GK4831@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
With two new methods, one to find the first match, returning its syscall
id and its index in whatever internal database it keeps the syscall
into, then one to find the next match, if any.
Implemented only on arches where we actually read the syscall table from
the kernel sources, i.e. x86-64 for now, all the others use the libaudit
method for which this returns -1, i.e. just stubs were added, with the
actual implementation using whatever libaudit functions for matching
that may be available.
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-i0sj4rxk1a63pfe9gl8z8irs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The branch history code has a loop detection function. With this, we can
get the number of iterations by calculating the removed loops.
While it would be nice for knowing the average cycles of iterations.
This patch adds up the cycles in branch entries of removed loops and
save the result to the next branch entry (e.g. branch entry A).
Finally it will display the iteration number and average cycles at the
"from" of branch entry A.
For example:
perf record -g -j any,save_type ./div
perf report --branch-history --no-children --stdio
--22.63%--main div.c:42 (RET CROSS_2M)
compute_flag div.c:28 (cycles:2 iter:173115 avg_cycles:2)
|
--10.73%--compute_flag div.c:27 (RET CROSS_2M)
rand rand.c:28 (cycles:1)
rand rand.c:28 (RET CROSS_2M)
__random random.c:298 (cycles:1)
__random random.c:297 (COND_BWD CROSS_2M)
__random random.c:295 (cycles:1)
__random random.c:295 (COND_BWD CROSS_2M)
__random random.c:295 (cycles:1)
__random random.c:295 (RET CROSS_2M)
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1502111115-18305-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
On x86, the plt header size is as same as the plt entry size, and can be
identified from shdr's sh_entsize of the plt.
But we can't assume that the sh_entsize of the plt shdr is always the
plt entry size in all architecture, and the plt header size may be not
as same as the plt entry size in some architecure.
On ARM, the plt header size is 20 bytes and the plt entry size is 12
bytes (don't consider the FOUR_WORD_PLT case) that refer to the binutils
implementation. The plt section is as follows:
Disassembly of section .plt:
000004a0 <__cxa_finalize@plt-0x14>:
4a0: e52de004 push {lr} ; (str lr, [sp, #-4]!)
4a4: e59fe004 ldr lr, [pc, #4] ; 4b0 <_init+0x1c>
4a8: e08fe00e add lr, pc, lr
4ac: e5bef008 ldr pc, [lr, #8]!
4b0: 00008424 .word 0x00008424
000004b4 <__cxa_finalize@plt>:
4b4: e28fc600 add ip, pc, #0, 12
4b8: e28cca08 add ip, ip, #8, 20 ; 0x8000
4bc: e5bcf424 ldr pc, [ip, #1060]! ; 0x424
000004c0 <printf@plt>:
4c0: e28fc600 add ip, pc, #0, 12
4c4: e28cca08 add ip, ip, #8, 20 ; 0x8000
4c8: e5bcf41c ldr pc, [ip, #1052]! ; 0x41c
On AARCH64, the plt header size is 32 bytes and the plt entry size is 16
bytes. The plt section is as follows:
Disassembly of section .plt:
0000000000000560 <__cxa_finalize@plt-0x20>:
560: a9bf7bf0 stp x16, x30, [sp,#-16]!
564: 90000090 adrp x16, 10000 <__FRAME_END__+0xf8a8>
568: f944be11 ldr x17, [x16,#2424]
56c: 9125e210 add x16, x16, #0x978
570: d61f0220 br x17
574: d503201f nop
578: d503201f nop
57c: d503201f nop
0000000000000580 <__cxa_finalize@plt>:
580: 90000090 adrp x16, 10000 <__FRAME_END__+0xf8a8>
584: f944c211 ldr x17, [x16,#2432]
588: 91260210 add x16, x16, #0x980
58c: d61f0220 br x17
0000000000000590 <__gmon_start__@plt>:
590: 90000090 adrp x16, 10000 <__FRAME_END__+0xf8a8>
594: f944c611 ldr x17, [x16,#2440]
598: 91262210 add x16, x16, #0x988
59c: d61f0220 br x17
NOTES:
In addition to ARM and AARCH64, other architectures, such as
s390/alpha/mips/parisc/poperpc/sh/sparc/xtensa also need to consider
this issue.
Signed-off-by: Li Bin <huawei.libin@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: David Tolnay <dtolnay@gmail.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: zhangmengting@huawei.com
Link: http://lkml.kernel.org/r/1496622849-21877-1-git-send-email-huawei.libin@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The commit 9aaf5a5f47 ("perf probe: Check kprobes blacklist when
adding new events"), 'perf probe' supports checking the blacklist of the
fuctions which can not be probed. But the checking condition is wrong,
that the end_addr of the symbol which is the start_addr of the next
symbol can't be included.
Committer notes:
IOW make it match its kernel counterpart in kernel/kprobes.c:
bool within_kprobe_blacklist(unsigned long addr)
Each entry have as its end address not its end address, but the first
address _outside_ that symbol, which for related functions, is the first
address of the next symbol, like these from kernel/trace/trace_probe.c:
0xffffffffbd198df0-0xffffffffbd198e40 print_type_u8
0xffffffffbd198e40-0xffffffffbd198e90 print_type_u16
0xffffffffbd198e90-0xffffffffbd198ee0 print_type_u32
0xffffffffbd198ee0-0xffffffffbd198f30 print_type_u64
0xffffffffbd198f30-0xffffffffbd198f80 print_type_s8
0xffffffffbd198f80-0xffffffffbd198fd0 print_type_s16
0xffffffffbd198fd0-0xffffffffbd199020 print_type_s32
0xffffffffbd199020-0xffffffffbd199070 print_type_s64
0xffffffffbd199070-0xffffffffbd1990c0 print_type_x8
0xffffffffbd1990c0-0xffffffffbd199110 print_type_x16
0xffffffffbd199110-0xffffffffbd199160 print_type_x32
0xffffffffbd199160-0xffffffffbd1991b0 print_type_x64
But not always:
0xffffffffbd1997b0-0xffffffffbd1997c0 fetch_kernel_stack_address (kernel/trace/trace_probe.c)
0xffffffffbd1c57f0-0xffffffffbd1c58b0 __context_tracking_enter (kernel/context_tracking.c)
Signed-off-by: Li Bin <huawei.libin@huawei.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>
Cc: zhangmengting@huawei.com
Fixes: 9aaf5a5f47 ("perf probe: Check kprobes blacklist when adding new events")
Link: http://lkml.kernel.org/r/1504011443-7269-1-git-send-email-huawei.libin@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding dump_read function to gather all the dump output of read
function. Adding output of enabled and running times and id if enabled
(3 new lines with '...' prefix below).
$ perf record -s ...
$ perf report -D
958358311769 0x91f8 [0x40]: PERF_RECORD_READ: 3339 3339 cycles:u 0
... time enabled : 958358313731
... time running : 958358313731
... id : 80
Committer note:
Do not use 'read' as a variable name as it breaks the build on older
systems, such as RHEL6:
CC /tmp/build/perf/util/session.o
cc1: warnings being treated as errors
util/session.c: In function 'dump_read':
util/session.c:1132: error: declaration of 'read' shadows a global declaration
/usr/include/bits/unistd.h:35: error: shadowed declaration is here
mv: cannot stat `/tmp/build/perf/util/.session.o.tmp': No such file or directory
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170824162737.7813-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
