It was just freezing instead of informing about the SEGV, fix it and
also print a backtrace, just like in the TUI mode and in 'perf trace'.
Tested by provoking a NULL deref when pressing 'z':
0.31% libc-2.20.so [.] malloc_consolidate
0.31% ld-2.20.so [.] _dl_relocate_object
0.28% cc1 [.] ht_lookup
0.28% cc1 [.] ira_init_register_move_cost
perf: Segmentation fault
Obtained 7 stack frames.
perf(dump_stack+0x32) [0x4d69f2]
perf(sighandler_dump_stack+0x29) [0x4d6a89]
/lib64/libc.so.6(+0x34960) [0x7f5064333960]
perf() [0x438790]
/lib64/libpthread.so.0(+0x752a) [0x7f50663dd52a]
/lib64/libc.so.6(clone+0x6d) [0x7f50643ff22d]
#
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.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-pewrpzqd29rgmhu2wkk7fhww@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now that we can process branch data in annotate it makes sense to
support enabling branch recording from top too. Most of the code needed
for this is already in shared code with report. But we need to add:
- The option parsing code (using shared code from the previous patch)
- Document the options
- Set up the IPC/cycles accounting state in the top session
- Call the accounting code in the hist iter callback
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1437233094-12844-8-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
In addition to using refcounts for the struct thread lifetime
management, we need to protect access to machine->threads from
concurrent access.
That happens in 'perf top', where a thread processes events, inserting
and deleting entries from that rb_tree while another thread decays
hist_entries, that end up dropping references and ultimately deleting
threads from the rb_tree and releasing its resources when no further
hist_entry (or other data structures, like in 'perf sched') references
it.
So the rule is the same for refcounts + protected trees in the kernel,
get the tree lock, find object, bump the refcount, drop the tree lock,
return, use object, drop the refcount if no more use of it is needed,
keep it if storing it in some other data structure, drop when releasing
that data structure.
I.e. pair "t = machine__find(new)_thread()" with a "thread__put(t)", and
"perf_event__preprocess_sample(&al)" with "addr_location__put(&al)".
The addr_location__put() one is because as we return references to
several data structures, we may end up adding more reference counting
for the other data structures and then we'll drop it at
addr_location__put() time.
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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-bs9rt4n0jw3hi9f3zxyy3xln@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf top raise a warning if a kernel sample is collected but kernel map
is restricted. The warning message needs to dereference al.map->dso...
However, previous perf_event__preprocess_sample() doesn't always
guarantee al.map != NULL, for example, when kernel map is restricted.
This patch validates al.map before dereferencing, avoid the segfault.
Before this patch:
$ cat /proc/sys/kernel/kptr_restrict
1
$ perf top -p 120183
perf: Segmentation fault
-------- backtrace --------
/path/to/perf[0x509868]
/lib64/libc.so.6(+0x3545f)[0x7f9a1540045f]
/path/to/perf[0x448820]
/path/to/perf(cmd_top+0xe3c)[0x44a5dc]
/path/to/perf[0x4766a2]
/path/to/perf(main+0x5f5)[0x42e545]
/lib64/libc.so.6(__libc_start_main+0xf4)[0x7f9a153ecbd4]
/path/to/perf[0x42e674]
And gdb call trace:
Program received signal SIGSEGV, Segmentation fault.
perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0)
at builtin-top.c:736
736 !RB_EMPTY_ROOT(&al.map->dso->symbols[MAP__FUNCTION]) ?
(gdb) bt
#0 perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0)
at builtin-top.c:736
#1 perf_top__mmap_read_idx (top=top@entry=0x7fffffffa8a0, idx=idx@entry=0) at builtin-top.c:855
#2 0x000000000044a5dd in perf_top__mmap_read (top=0x7fffffffa8a0) at builtin-top.c:872
#3 __cmd_top (top=0x7fffffffa8a0) at builtin-top.c:997
#4 cmd_top (argc=<optimized out>, argv=<optimized out>, prefix=<optimized out>) at builtin-top.c:1267
#5 0x00000000004766a3 in run_builtin (p=p@entry=0x8a6ce8 <commands+264>, argc=argc@entry=3, argv=argv@entry=0x7fffffffdf70)
at perf.c:371
#6 0x000000000042e546 in handle_internal_command (argv=0x7fffffffdf70, argc=3) at perf.c:430
#7 run_argv (argv=0x7fffffffdcf0, argcp=0x7fffffffdcfc) at perf.c:474
#8 main (argc=3, argv=0x7fffffffdf70) at perf.c:589
(gdb)
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1429946703-80807-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before, when some problem happened while trying to load the kernel
symtab, 'perf top' would show:
┌─Warning:───────────────────────────┐
│The vmlinux file can't be used. │
│Kernel samples will not be resolved.│
│ │
│ │
│Press any key... │
└────────────────────────────────────┘
Now, it reports:
# perf top --vmlinux /dev/null
┌─Warning:───────────────────────────────────────────┐
│The /tmp/passwd file can't be used: Invalid ELF file│
│Kernel samples will not be resolved. │
│ │
│ │
│Press any key... │
└────────────────────────────────────────────────────┘
This is possible because we now register the reason for not being able
to load the symtab in the dso->load_errno member, and provide a
dso__strerror_load() routine to format this error into a strerror like
string with a short reason for the error while loading.
That can be just forwarding the dso__strerror_load() call to
strerror_r(), or, for a separate errno range providing a custom message.
Reported-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-u5rb5uq63xqhkfb8uv2lxd5u@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is due to duplicated unistd inclusion (via uClibc headers + kernel headers)
Also seen on ARM uClibc based tools
------- ARC build ---------->8-------------
CC util/evlist.o
In file included from
~/arc/k.org/arch/arc/include/uapi/asm/unistd.h:25:0,
from util/../perf-sys.h:10,
from util/../perf.h:15,
from util/event.h:7,
from util/event.c:3:
~/arc/k.org/include/uapi/asm-generic/unistd.h:906:0:
warning: "__NR_fcntl64" redefined [enabled by default]
#define __NR_fcntl64 __NR3264_fcntl
^
In file included from
~/arc/gnu/INSTALL_1412-arc-2014.12-rc1/arc-snps-linux-uclibc/sysroot/usr/include/sys/syscall.h:24:0,
from util/../perf-sys.h:6,
----------------->8-------------------
------- ARM build ---------->8-------------
CC FPIC plugin_scsi.o
In file included from util/../perf-sys.h:9:0,
from util/../perf.h:15,
from util/cache.h:7,
from perf.c:12:
~/arc/k.org/arch/arm/include/uapi/asm/unistd.h:28:0:
warning: "__NR_restart_syscall" redefined [enabled by default]
In file included from
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/sys/syscall.h:25:0,
from util/../perf-sys.h:6,
from util/../perf.h:15,
from util/cache.h:7,
from perf.c:12:
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/bits/sysnum.h:17:0:
note: this is the location of the previous definition
----------------->8-------------------
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421156604-30603-4-git-send-email-vgupta@synopsys.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently vmlinux_path__init() only tries to find vmlinux file from
current directory, /boot and some canonical directories with version
number of the running kernel. This can be a problem when reporting old
data recorded on a kernel version not running currently.
We can use --symfs option for this but it's annoying for user to do it
always. As we already have the info in the perf.data file, it can be
changed to use it for the search automatically.
Before:
$ perf report
...
# Samples: 4K of event 'cpu-clock'
# Event count (approx.): 1067250000
#
# Overhead Command Shared Object Symbol
# ........ .......... ................. ..............................
71.87% swapper [kernel.kallsyms] [k] recover_probed_instruction
After:
# Overhead Command Shared Object Symbol
# ........ .......... ................. ....................
71.87% swapper [kernel.kallsyms] [k] native_safe_halt
This requires to change signature of symbol__init() to receive struct
perf_session_env *.
Reported-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1407825645-24586-14-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add top.children config option for setting default value of
callchain accumulation. It affects the output only if one of
-g or --call-graph option is given as well.
A user can write .perfconfig file like below to enable accumulation
by default:
$ cat ~/.perfconfig
[top]
children = true
And it can be disabled through command line:
$ perf top --no-children
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arun Sharma <asharma@fb.com>
Tested-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1401335910-16832-22-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
The --fields option is to allow user setup output field in any order.
It can receive any sort keys and following (hpp) fields:
overhead, overhead_sys, overhead_us, sample and period
If guest profiling is enabled, overhead_guest_{sys,us} will be
available too.
More more information, please see previous patch "perf report:
Add -F option to specify output fields"
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1400480762-22852-15-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
The --percentage option is for controlling overhead percentage
displayed. It can only receive either of "relative" or "absolute".
Move the parser callback function into a common location since it's
used by multiple commands now.
For more information, please see previous commit same thing done to
"perf report".
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1397145720-8063-4-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
When filtering by thread, dso or symbol on TUI it also update total
period so that the output shows different result than no filter - the
percentage changed to relative to filtered entries only. Sometimes
this is not desired since users might expect same results with filter.
So new filtered_* fields to hists->stats to count them separately.
They'll be controlled/used by user later.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1397145720-8063-2-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
The TUI of perf report and top support annotation, but stdio and GTK
don't. So it should be checked before calling hist_entry__inc_addr_
samples() to avoid wasting resources that will never be used.
perf annotate need it regardless of UI and sort keys, so the check
of whether to allocate resources should be on the tools that have
annotate as an option in the TUI, 'report' and 'top', not on the
function called by all of them.
It caused perf annotate on ppc64 to produce zero output, since the
buckets were not being allocated.
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1392859976-32760-1-git-send-email-namhyung@kernel.org
[ Renamed (report,top)__needs_annotate() to ui__has_annotation() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
