Post processing at 'perf record' takes a long time on big machines.
What it does is to find the build-id of binaries found in the event
stream, so that it can make sure, at 'report' time, that the symtabs (be
it ELF, kallsyms, etc) being used to resolve symbols are the ones
matching the binaries found at 'record' time.
Sometimes we just want to skip this processing of events at the end of
the session to get quicker results, making sure the binaries haven't
changed from 'record' to 'report' time.
Add a new config option to control this behavior.
The record.build-id config variable can have one of the following
values:
- cache: post-process data and save/update the binaries into the
build-id cache (in ~/.debug). This is the default.
- no-cache: post-process the data but not update the build-id cache.
Same effect as using the -N option.
- skip: skip post-processing and do not update the cache.
Same effect as using the -B option.
Reported-and-Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: http://lkml.kernel.org/r/1450144196-22957-1-git-send-email-namhyung@kernel.org
[ Added some more text to the documentation ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Make perf-record command support --vmlinux option if BPF_PROLOGUE is on.
'perf record' needs vmlinux as the source of DWARF info to generate
prologue for BPF programs, so path of vmlinux should be specified.
Short name 'k' has been taken by 'clockid'. This patch skips the short
option name and uses '--vmlinux' for vmlinux path.
Documentation is also updated.
Test result:
In a production (or broken) environment:
(by:
# rm -rf ~/.debug/
# mv /lib/modules/`uname -r`/build/vmlinux /tmp/
)
# ./perf record -e ./test_bpf_base.c ls
Failed to find the path for kernel: No such file or directory
event syntax error: './test_bpf_base.c'
\___ You need to check probing points in BPF file
...
# ./perf record --vmlinux /tmp/vmlinux -e ./test_bpf_base.c ls
...
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.011 MB perf.data ]
Help messages when build with NO_LIBBPF:
# ./perf record -h
--transaction sample transaction flags (special events only)
--vmlinux <file> vmlinux pathname
(not built-in because NO_LIBBPF=1)
# ./perf record --vmlinux /tmp/vmlinux ls /
Warning: option `vmlinux' is being ignored because NO_LIBBPF=1
...
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.011 MB perf.data (11 samples) ]
Help messages when build with NO_DWARF:
# ./perf record -h
--transaction sample transaction flags (special events only)
--vmlinux <file> vmlinux pathname
(not built-in because NO_DWARF=1)
Signed-off-by: He Kuang <hekuang@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1450089563-122430-15-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch keeps options of perf builtins same in all conditions. If
one option is disabled because of compiling options, users should be
notified.
Masami suggested another implementation in [1] that, by adding a
OPTION_NEXT_DEPENDS option before those options in the 'struct option'
array, options parser knows an option is disabled. However, in some
cases this array is reordered (options__order()). In addition, in
parse-option.c that array is const, so we can't simply merge
information in decorator option into the affacted option.
This patch chooses a simpler implementation that, introducing a
set_option_nobuild() function and two option parsing flags. Builtins
with such options should call set_option_nobuild() before option
parsing. The complexity of this patch is because we want some of options
can be skipped safely. In this case their arguments should also be
consumed.
Options in 'perf record' and 'perf probe' are fixed in this patch.
[1] http://lkml.kernel.org/g/50399556C9727B4D88A595C8584AAB3752627CD4@GSjpTKYDCembx32.service.hitachi.net
Test result:
Normal case:
# ./perf probe --vmlinux /tmp/vmlinux sys_write
Added new event:
probe:sys_write (on sys_write)
You can now use it in all perf tools, such as:
perf record -e probe:sys_write -aR sleep 1
Build with NO_DWARF=1:
# ./perf probe -L sys_write
Error: switch `L' is not available because NO_DWARF=1
Usage: perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]
or: perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]
or: perf probe [<options>] --del '[GROUP:]EVENT' ...
or: perf probe --list [GROUP:]EVENT ...
or: perf probe [<options>] --funcs
-L, --line <FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]>
Show source code lines.
(not built-in because NO_DWARF=1)
# ./perf probe -k /tmp/vmlinux sys_write
Warning: switch `k' is being ignored because NO_DWARF=1
Added new event:
probe:sys_write (on sys_write)
You can now use it in all perf tools, such as:
perf record -e probe:sys_write -aR sleep 1
# ./perf probe --vmlinux /tmp/vmlinux sys_write
Warning: option `vmlinux' is being ignored because NO_DWARF=1
Added new event:
[SNIP]
# ./perf probe -l
Usage: perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]
or: perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]
...
-k, --vmlinux <file> vmlinux pathname
(not built-in because NO_DWARF=1)
-L, --line <FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]>
Show source code lines.
(not built-in because NO_DWARF=1)
...
-V, --vars <FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT>
Show accessible variables on PROBEDEF
(not built-in because NO_DWARF=1)
--externs Show external variables too (with --vars only)
(not built-in because NO_DWARF=1)
--no-inlines Don't search inlined functions
(not built-in because NO_DWARF=1)
--range Show variables location range in scope (with --vars only)
(not built-in because NO_DWARF=1)
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1450089563-122430-14-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
[The kernel patch needed for this is in tip now (b16a5b52eb perf/x86:
Add option to disable ...) So this user tools patch to make use of it
should be merged now]
Automatically disable collecting branch flags and cycles with
--call-graph lbr. This allows avoiding a bunch of extra MSR
reads in the PMI on Skylake.
When the kernel doesn't support the new flags they are automatically
cleared in the fallback code.
v2: Switch to use branch_sample_type instead of sample_type.
Adjust description.
Fix the fallback logic.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1449879144-29074-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We should always return from thread__new(), the constructor, with the
object with a reference count of one, so that:
struct thread *thread = thread__new();
thread__put(thread);
Will call thread__delete().
If any reference is made to that 'thread' variable, it better use
thread__get(thread) to hold a reference.
We were returning with thread->refcnt set to zero, fix it and some cases
where thread__delete() was being called, which were not a problem
because just one reference was being used, now that we set it to 1, use
thread__put() instead.
Reported-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-4b9mkuk66to4ecckpmpvqx6s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Fix 'perf top' annotation in --stdio (Namhyung Kim)
- Support hw breakpoint events (mem:0xAddress) in the default output mode in
'perf script' (Wang Nan)
Infrastructure changes:
- Do not hold the hists lock while emitting one specific warning (Namhyung Kim)
- Fetch map names from correct strtab, worked so far because llvm/clang
uses just one string table (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Josh Poimboeuf
Namhyung Kim
He Kuang
Wang Nan
Andi Kleen
Arnaldo Carvalho de Melo
Ingo Molnar