Since debuginfo__find_probe_point() uses dwarf_entrypc() for finding the
entry address of the function on which a probe is, it will fail when the
function DIE has only ranges attribute.
To fix this issue, use die_entrypc() instead of dwarf_entrypc().
Without this fix, perf probe -l shows incorrect offset:
# perf probe -l
probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask+18446744071579263632@work/linux/linux/kernel/cpu.c)
probe:clear_tasks_mm_cpumask_1 (on clear_tasks_mm_cpumask+18446744071579263752@work/linux/linux/kernel/cpu.c)
With this:
# perf probe -l
probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask@work/linux/linux/kernel/cpu.c)
probe:clear_tasks_mm_cpumask_1 (on clear_tasks_mm_cpumask:21@work/linux/linux/kernel/cpu.c)
Committer testing:
Before:
[root@quaco ~]# perf probe -l
probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask+18446744071579765152@kernel/cpu.c)
[root@quaco ~]#
After:
[root@quaco ~]# perf probe -l
probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask@kernel/cpu.c)
[root@quaco ~]#
Fixes: 1d46ea2a6a ("perf probe: Fix listing incorrect line number with inline function")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157199321227.8075.14655572419136993015.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix perf probe to probe an inlne function which has no entry pc
or low pc but only has ranges attribute.
This seems very rare case, but I could find a few examples, as
same as probe_point_search_cb(), use die_entrypc() to get the
entry address in probe_point_inline_cb() too.
Without this patch:
# perf probe -D __amd_put_nb_event_constraints
Failed to get entry address of __amd_put_nb_event_constraints.
Probe point '__amd_put_nb_event_constraints' not found.
Error: Failed to add events.
With this patch:
# perf probe -D __amd_put_nb_event_constraints
p:probe/__amd_put_nb_event_constraints amd_put_event_constraints+43
Committer testing:
Before:
[root@quaco ~]# perf probe -D __amd_put_nb_event_constraints
Failed to get entry address of __amd_put_nb_event_constraints.
Probe point '__amd_put_nb_event_constraints' not found.
Error: Failed to add events.
[root@quaco ~]#
After:
[root@quaco ~]# perf probe -D __amd_put_nb_event_constraints
p:probe/__amd_put_nb_event_constraints _text+33789
[root@quaco ~]#
Fixes: 4ea42b1814 ("perf: Add perf probe subcommand, a kprobe-event setup helper")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157199320336.8075.16189530425277588587.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix 'perf probe' to probe a function which has no entry pc or low pc but
only has ranges attribute.
probe_point_search_cb() uses dwarf_entrypc() to get the probe address,
but that doesn't work for the function DIE which has only ranges
attribute. Use die_entrypc() instead.
Without this fix:
# perf probe -k ../build-x86_64/vmlinux -D clear_tasks_mm_cpumask:0
Probe point 'clear_tasks_mm_cpumask' not found.
Error: Failed to add events.
With this:
# perf probe -k ../build-x86_64/vmlinux -D clear_tasks_mm_cpumask:0
p:probe/clear_tasks_mm_cpumask clear_tasks_mm_cpumask+0
Committer testing:
Before:
[root@quaco ~]# perf probe clear_tasks_mm_cpumask:0
Probe point 'clear_tasks_mm_cpumask' not found.
Error: Failed to add events.
[root@quaco ~]#
After:
[root@quaco ~]# perf probe clear_tasks_mm_cpumask:0
Added new event:
probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask)
You can now use it in all perf tools, such as:
perf record -e probe:clear_tasks_mm_cpumask -aR sleep 1
[root@quaco ~]#
Using it with 'perf trace':
[root@quaco ~]# perf trace -e probe:clear_tasks_mm_cpumask
Doesn't seem to be used in x86_64:
$ find . -name "*.c" | xargs grep clear_tasks_mm_cpumask
./kernel/cpu.c: * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU
./kernel/cpu.c:void clear_tasks_mm_cpumask(int cpu)
./arch/xtensa/kernel/smp.c: clear_tasks_mm_cpumask(cpu);
./arch/csky/kernel/smp.c: clear_tasks_mm_cpumask(cpu);
./arch/sh/kernel/smp.c: clear_tasks_mm_cpumask(cpu);
./arch/arm/kernel/smp.c: clear_tasks_mm_cpumask(cpu);
./arch/powerpc/mm/nohash/mmu_context.c: clear_tasks_mm_cpumask(cpu);
$ find . -name "*.h" | xargs grep clear_tasks_mm_cpumask
./include/linux/cpu.h:void clear_tasks_mm_cpumask(int cpu);
$ find . -name "*.S" | xargs grep clear_tasks_mm_cpumask
$
Fixes: e1ecbbc3fa ("perf probe: Fix to handle optimized not-inlined functions")
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157199319438.8075.4695576954550638618.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since there are some DIE which has only ranges instead of the
combination of entrypc/highpc, address verification must use
dwarf_haspc() instead of dwarf_entrypc/dwarf_highpc.
Also, the ranges only DIE will have a partial code in different section
(e.g. unlikely code will be in text.unlikely as "FUNC.cold" symbol). In
that case, we can not use dwarf_entrypc() or die_entrypc(), because the
offset from original DIE can be a minus value.
Instead, this simply gets the symbol and offset from symtab.
Without this patch;
# perf probe -D clear_tasks_mm_cpumask:1
Failed to get entry address of clear_tasks_mm_cpumask
Error: Failed to add events.
And with this patch:
# perf probe -D clear_tasks_mm_cpumask:1
p:probe/clear_tasks_mm_cpumask clear_tasks_mm_cpumask+0
p:probe/clear_tasks_mm_cpumask_1 clear_tasks_mm_cpumask+5
p:probe/clear_tasks_mm_cpumask_2 clear_tasks_mm_cpumask+8
p:probe/clear_tasks_mm_cpumask_3 clear_tasks_mm_cpumask+16
p:probe/clear_tasks_mm_cpumask_4 clear_tasks_mm_cpumask+82
Committer testing:
I managed to reproduce the above:
[root@quaco ~]# perf probe -D clear_tasks_mm_cpumask:1
p:probe/clear_tasks_mm_cpumask _text+919968
p:probe/clear_tasks_mm_cpumask_1 _text+919973
p:probe/clear_tasks_mm_cpumask_2 _text+919976
[root@quaco ~]#
But then when trying to actually put the probe in place, it fails if I
use :0 as the offset:
[root@quaco ~]# perf probe -L clear_tasks_mm_cpumask | head -5
<clear_tasks_mm_cpumask@/usr/src/debug/kernel-5.2.fc30/linux-5.2.18-200.fc30.x86_64/kernel/cpu.c:0>
0 void clear_tasks_mm_cpumask(int cpu)
1 {
2 struct task_struct *p;
[root@quaco ~]# perf probe clear_tasks_mm_cpumask:0
Probe point 'clear_tasks_mm_cpumask' not found.
Error: Failed to add events.
[root@quaco
The next patch is needed to fix this case.
Fixes: 576b523721 ("perf probe: Fix probing symbols with optimization suffix")
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157199318513.8075.10463906803299647907.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix die_walk_lines() to list the function entry line correctly. Since
the dwarf_entrypc() does not return the entry pc if the DIE has only
range attribute, __die_walk_funclines() fails to list the declaration
line (entry line) in that case.
To solve this issue, this introduces die_entrypc() which correctly
returns the entry PC (the first address range) even if the DIE has only
range attribute. With this fix die_walk_lines() shows the function entry
line is able to probe correctly.
Fixes: 4cc9cec636 ("perf probe: Introduce lines walker interface")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157190837419.1859.4619125803596816752.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since some inlined functions are in lexical blocks of given function, we
have to recursively walk through the DIE tree. Without this fix,
perf-probe -L can miss the inlined functions which is in a lexical block
(like if (..) { func() } case.)
However, even though, to walk the lines in a given function, we don't
need to follow the children DIE of inlined functions because those do
not have any lines in the specified function.
We need to walk though whole trees only if we walk all lines in a given
file, because an inlined function can include another inlined function
in the same file.
Fixes: b0e9cb2802 ("perf probe: Fix to search nested inlined functions in CU")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157190836514.1859.15996864849678136353.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix die_is_func_instance() to find range-only function instance.
In some case, a function instance can be made without any low PC or
entry PC, but only with address ranges by optimization. (e.g. cold text
partially in "text.unlikely" section) To find such function instance, we
have to check the range attribute too.
Fixes: e1ecbbc3fa ("perf probe: Fix to handle optimized not-inlined functions")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157190835669.1859.8368628035930950596.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Support directory output that contains a regular perf.data file, named
"data". By default the directory is named perf.data i.e.
perf.data
└── data
Most of the infrastructure to support a directory is already there. This
patch makes the changes needed to support the format above.
Presently there is no 'perf record' option to output a directory.
This is preparation for adding support for putting a copy of /proc/kcore in
the directory.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191004083121.12182-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Daniel Borkmann says:
====================
pull-request: bpf 2019-11-02
The following pull-request contains BPF updates for your *net* tree.
We've added 6 non-merge commits during the last 6 day(s) which contain
a total of 8 files changed, 35 insertions(+), 9 deletions(-).
The main changes are:
1) Fix ppc BPF JIT's tail call implementation by performing a second pass
to gather a stable JIT context before opcode emission, from Eric Dumazet.
2) Fix build of BPF samples sys_perf_event_open() usage to compiled out
unavailable test_attr__{enabled,open} checks. Also fix potential overflows
in bpf_map_{area_alloc,charge_init} on 32 bit archs, from Björn Töpel.
3) Fix narrow loads of bpf_sysctl context fields with offset > 0 on big endian
archs like s390x and also improve the test coverage, from Ilya Leoshkevich.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Since its values are in two ranges of values we ended up codifying it
using a 'struct strarrays', so now hook it up with STUL_STRARRAYS so
that we can do:
# perf trace -e syscalls:*enter_fcntl --filter=cmd==SETLK||cmd==SETLKW
0.000 sssd_kcm/19021 syscalls:sys_enter_fcntl(fd: 13</var/lib/sss/secrets/secrets.ldb>, cmd: SETLK, arg: 0x7ffcf0a4dee0)
1.523 sssd_kcm/19021 syscalls:sys_enter_fcntl(fd: 13</var/lib/sss/secrets/secrets.ldb>, cmd: SETLK, arg: 0x7ffcf0a4de90)
1.629 sssd_kcm/19021 syscalls:sys_enter_fcntl(fd: 13</var/lib/sss/secrets/secrets.ldb>, cmd: SETLK, arg: 0x7ffcf0a4de90)
2.711 sssd_kcm/19021 syscalls:sys_enter_fcntl(fd: 13</var/lib/sss/secrets/secrets.ldb>, cmd: SETLK, arg: 0x7ffcf0a4de70)
^C#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-mob96wyzri4r3rvyigqfjv0a@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add mmaping tests that generates prctl call on every cpu validates it
gets all the related events in ring buffer.
Committer testing:
# make -C tools/perf/lib tests
make: Entering directory '/home/acme/git/perf/tools/perf/lib'
LINK test-cpumap-a
LINK test-threadmap-a
LINK test-evlist-a
LINK test-evsel-a
LINK test-cpumap-so
LINK test-threadmap-so
LINK test-evlist-so
LINK test-evsel-so
running static:
- running test-cpumap.c...OK
- running test-threadmap.c...OK
- running test-evlist.c...OK
- running test-evsel.c...OK
running dynamic:
- running test-cpumap.c...OK
- running test-threadmap.c...OK
- running test-evlist.c...OK
- running test-evsel.c...OK
make: Leaving directory '/home/acme/git/perf/tools/perf/lib'
#
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: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20191017105918.20873-8-jolsa@kernel.org
[ Added _GNU_SOURCE define for sched.h to get sched_[gs]et_affinity
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As there are several discussions for enabling perf breakpoint signal
testing on arm64 platform: arm64 needs to rely on single-step to execute
the breakpointed instruction and then reinstall the breakpoint exception
handler. But if we hook the breakpoint with a signal, the signal
handler will do the stepping rather than the breakpointed instruction,
this causes infinite loops as below:
Kernel space | Userspace
---------------------------------|--------------------------------
| __test_function() -> hit
| breakpoint
breakpoint_handler() |
`-> user_enable_single_step() |
do_signal() |
| sig_handler() -> Step one
| instruction and
| trap to kernel
single_step_handler() |
`-> reinstall_suspended_bps() |
| __test_function() -> hit
| breakpoint again and
| repeat up flow infinitely
As Will Deacon mentioned [1]: "that we require the overflow handler to
do the stepping on arm/arm64, which is relied upon by GDB/ptrace. The
hw_breakpoint code is a complete disaster so my preference would be to
rip out the perf part and just implement something directly in ptrace,
but it's a pretty horrible job". Though Will commented this on arm
architecture, but the comment also can apply on arm64 architecture.
For complete information, I searched online and found a few years back,
Wang Nan sent one patch 'arm64: Store breakpoint single step state into
pstate' [2]; the patch tried to resolve this issue by avoiding single
stepping in signal handler and defer to enable the signal stepping when
return to __test_function(). The fixing was not merged due to the
concern for missing to handle different usage cases.
Based on the info, the most feasible way is to skip Perf breakpoint
signal testing for arm64 and this could avoid the duplicate
investigation efforts when people see the failure. This patch skips
this case on arm64 platform, which is same with arm architecture.
[1] https://lkml.org/lkml/2018/11/15/205
[2] https://lkml.org/lkml/2015/12/23/477
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Brajeswar Ghosh <brajeswar.linux@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lore.kernel.org/lkml/20191018085531.6348-3-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are some deprecated events listed by perf list. But we can't
remove them from perf list with ease because some old scripts may use
them.
Deprecated events are old names of renamed events. When an event gets
renamed the old name is kept around for some time and marked with
Deprecated. The newer Intel event lists in the tree already have these
headers.
So we need to keep them in the event list, but provide a new option to
show them. The new option is "--deprecated".
With this patch, the deprecated events are hidden by default but they
can be displayed when option "--deprecated" is enabled.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
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/20191015025357.8708-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
