summaryrefslogtreecommitdiff
path: root/tools/perf/util
AgeCommit message (Collapse)Author
2017-07-27perf intel-pt: Clear FUP flag on errorAdrian Hunter
commit 6a558f12dbe85437acbdec5e149ea07b5554eced upstream. Sometimes a FUP packet is associated with a TSX transaction and a flag is set to indicate that. Ensure that flag is cleared on any error condition because at that point the decoder can no longer assume it is correct. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1495786658-18063-9-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-27perf intel-pt: Ensure IP is zero when state is INTEL_PT_STATE_NO_IPAdrian Hunter
commit ad7167a8cd174ba7d8c0d0ed8d8410521206d104 upstream. A value of zero is used to indicate that there is no IP. Ensure the value is zero when the state is INTEL_PT_STATE_NO_IP. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1495786658-18063-5-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-27perf intel-pt: Fix missing stack clearAdrian Hunter
commit 12b7080609097753fd8198cc1daf589be3ec1cca upstream. The return compression stack must be cleared whenever there is a PSB. Fix one case where that was not happening. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1495786658-18063-4-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-27perf intel-pt: Improve sample timestampAdrian Hunter
commit 3f04d98e972b59706bd43d6cc75efac91f8fba50 upstream. The decoder uses its current timestamp in samples. Usually that is a timestamp that has already passed, but in some cases it is a timestamp for a branch that the decoder is walking towards, and consequently hasn't reached. Improve that situation by using the pkt_state to determine when to use the current or previous timestamp. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1495786658-18063-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-27perf intel-pt: Move decoder error setting into one conditionAdrian Hunter
commit 22c06892332d8916115525145b78e606e9cc6492 upstream. Move decoder error setting into one condition. Cc'ed to stable because later fixes depend on it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1495786658-18063-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf tools: Use readdir() instead of deprecated readdir_r() againArnaldo Carvalho de Melo
commit 22a9f41b555673e7499b97acf3ffb07bf0af31ad upstream. The readdir() function is thread safe as long as just one thread uses a DIR, which is the case when parsing tracepoint event definitions, to avoid breaking the build with glibc-2.23.90 (upcoming 2.24), use it instead of readdir_r(). See: http://man7.org/linux/man-pages/man3/readdir.3.html "However, in modern implementations (including the glibc implementation), concurrent calls to readdir() that specify different directory streams are thread-safe. In cases where multiple threads must read from the same directory stream, using readdir() with external synchronization is still preferable to the use of the deprecated readdir_r(3) function." Noticed while building on a Fedora Rawhide docker container. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.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-wddn49r6bz6wq4ee3dxbl7lo@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf pmu: Fix misleadingly indented assignment (whitespace)Markus Trippelsdorf
commit d85ce830eef6c10d1e9617172dea4681f02b8424 upstream. One line in perf_pmu__parse_unit() is indented wrongly, leading to a warning (=> error) from gcc 6: util/pmu.c:156:3: error: statement is indented as if it were guarded by... [-Werror=misleading-indentation] sret = read(fd, alias->unit, UNIT_MAX_LEN); ^~~~ util/pmu.c:153:2: note: ...this 'if' clause, but it is not if (fd == -1) ^~ Signed-off-by: Markus Trippelsdorf <markus@trippelsdorf.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Fixes: 410136f5dd96 ("tools/perf/stat: Add event unit and scale support") Link: http://lkml.kernel.org/r/20151214154440.GC1409@x4 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf tools: Remove duplicate const qualifierEric Engestrom
commit 3b556bced46aa6b1873da7faa18eff235e896adc upstream. Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1461577678-29517-1-git-send-email-eric.engestrom@imgtec.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf thread_map: Use readdir() instead of deprecated readdir_r()Arnaldo Carvalho de Melo
commit 3354cf71104de49326d19d2f9bdb1f66eea52ef4 upstream. The readdir() function is thread safe as long as just one thread uses a DIR, which is the case in thread_map, so, to avoid breaking the build with glibc-2.23.90 (upcoming 2.24), use it instead of readdir_r(). See: http://man7.org/linux/man-pages/man3/readdir.3.html "However, in modern implementations (including the glibc implementation), concurrent calls to readdir() that specify different directory streams are thread-safe. In cases where multiple threads must read from the same directory stream, using readdir() with external synchronization is still preferable to the use of the deprecated readdir_r(3) function." Noticed while building on a Fedora Rawhide docker container. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.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-del8h2a0f40z75j4r42l96l0@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf tools: Use readdir() instead of deprecated readdir_r()Arnaldo Carvalho de Melo
commit 7093b4c963cc4e344e490c774924a180602a7092 upstream. The readdir() function is thread safe as long as just one thread uses a DIR, which is the case when synthesizing events for pre-existing threads by traversing /proc, so, to avoid breaking the build with glibc-2.23.90 (upcoming 2.24), use it instead of readdir_r(). See: http://man7.org/linux/man-pages/man3/readdir.3.html "However, in modern implementations (including the glibc implementation), concurrent calls to readdir() that specify different directory streams are thread-safe. In cases where multiple threads must read from the same directory stream, using readdir() with external synchronization is still preferable to the use of the deprecated readdir_r(3) function." Noticed while building on a Fedora Rawhide docker container. CC /tmp/build/perf/util/event.o util/event.c: In function '__event__synthesize_thread': util/event.c:466:2: error: 'readdir_r' is deprecated [-Werror=deprecated-declarations] while (!readdir_r(tasks, &dirent, &next) && next) { ^~~~~ In file included from /usr/include/features.h:368:0, from /usr/include/stdint.h:25, from /usr/lib/gcc/x86_64-redhat-linux/6.0.0/include/stdint.h:9, from /git/linux/tools/include/linux/types.h:6, from util/event.c:1: /usr/include/dirent.h:189:12: note: declared here Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.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-i1vj7nyjp2p750rirxgrfd3c@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf scripting perl: Fix compile error with some perl5 versionsWang YanQing
commit d7dd112ea5cacf91ae72c0714c3b911eb6016fea upstream. Fix below compile error: CC util/scripting-engines/trace-event-perl.o In file included from /usr/lib/perl5/5.22.2/i686-linux/CORE/perl.h:5673:0, from util/scripting-engines/trace-event-perl.c:31: /usr/lib/perl5/5.22.2/i686-linux/CORE/inline.h: In function 'S__is_utf8_char_slow': /usr/lib/perl5/5.22.2/i686-linux/CORE/inline.h:270:5: error: nested extern declaration of 'Perl___notused' [-Werror=nested-externs] dTHX; /* The function called below requires thread context */ ^ cc1: all warnings being treated as errors After digging perl5 repository, I find out that we will meet this compile error with perl from v5.21.1 to v5.25.4 Signed-off-by: Wang YanQing <udknight@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/20170212024655.GA15997@udknight Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf thread_map: Correctly size buffer used with dirent->dt_nameArnaldo Carvalho de Melo
commit bdf23a9a190d7ecea092fd5c4aabb7d4bd0a9980 upstream. The size of dirent->dt_name is NAME_MAX + 1, but the size for the 'path' buffer is hard coded at 256, which may truncate it because we also prepend "/proc/", so that all that into account and thank gcc 7 for this warning: /git/linux/tools/perf/util/thread_map.c: In function 'thread_map__new_by_uid': /git/linux/tools/perf/util/thread_map.c:119:39: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size 250 [-Werror=format-truncation=] snprintf(path, sizeof(path), "/proc/%s", dirent->d_name); ^~ In file included from /usr/include/stdio.h:939:0, from /git/linux/tools/perf/util/thread_map.c:5: /usr/include/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 7 and 262 bytes into a destination of size 256 return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ __bos (__s), __fmt, __va_arg_pack ()); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.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-csy0r8zrvz5efccgd4k12c82@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15perf intel-pt: Use __fallthroughArnaldo Carvalho de Melo
commit 7ea6856d6f5629d742edc23b8b76e6263371ef45 upstream. To address new warnings emmited by gcc 7, e.g.:: CC /tmp/build/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.o CC /tmp/build/perf/tests/parse-events.o util/intel-pt-decoder/intel-pt-pkt-decoder.c: In function 'intel_pt_pkt_desc': util/intel-pt-decoder/intel-pt-pkt-decoder.c:499:6: error: this statement may fall through [-Werror=implicit-fallthrough=] if (!(packet->count)) ^ util/intel-pt-decoder/intel-pt-pkt-decoder.c:501:2: note: here case INTEL_PT_CYC: ^~~~ CC /tmp/build/perf/util/intel-pt-decoder/intel-pt-decoder.o cc1: all warnings being treated as errors Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: David Ahern <dsahern@gmail.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-mf0hw789pu9x855us5l32c83@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15tools strfilter: Use __fallthroughArnaldo Carvalho de Melo
commit d64b721d27aef3fbeb16ecda9dd22ee34818ff70 upstream. The implicit fall through case label here is intended, so let us inform that to gcc >= 7: util/strfilter.c: In function 'strfilter_node__sprint': util/strfilter.c:270:6: error: this statement may fall through [-Werror=implicit-fallthrough=] if (len < 0) ^ util/strfilter.c:272:2: note: here case '!': ^~~~ cc1: all warnings being treated as errors Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.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-z2dpywg7u8fim000hjfbpyfm@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15tools string: Use __fallthrough in perf_atoll()Arnaldo Carvalho de Melo
commit 94bdd5edb34e472980d1e18b4600d6fb92bd6b0a upstream. The implicit fall through case label here is intended, so let us inform that to gcc >= 7: CC /tmp/build/perf/util/string.o util/string.c: In function 'perf_atoll': util/string.c:22:7: error: this statement may fall through [-Werror=implicit-fallthrough=] if (*p) ^ util/string.c:24:3: note: here case '\0': ^~~~ Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.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-0ophb30v9apkk6o95el0rqlq@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05perf probe: Fix to show correct locations for events on modulesMasami Hiramatsu
[ Upstream commit d2d4edbebe07ddb77980656abe7b9bc7a9e0cdf7 ] Fix to show correct locations for events on modules by relocating given address instead of retrying after failure. This happens when the module text size is big enough, bigger than sh_addr, because the original code retries with given address + sh_addr if it failed to find CU DIE at the given address. Any address smaller than sh_addr always fails and it retries with the correct address, but addresses bigger than sh_addr will get a CU DIE which is on the given address (not adjusted by sh_addr). In my environment(x86-64), the sh_addr of ".text" section is 0x10030. Since i915 is a huge kernel module, we can see this issue as below. $ grep "[Tt] .*\[i915\]" /proc/kallsyms | sort | head -n1 ffffffffc0270000 t i915_switcheroo_can_switch [i915] ffffffffc0270000 + 0x10030 = ffffffffc0280030, so we'll check symbols cross this boundary. $ grep "[Tt] .*\[i915\]" /proc/kallsyms | grep -B1 ^ffffffffc028\ | head -n 2 ffffffffc027ff80 t haswell_init_clock_gating [i915] ffffffffc0280110 t valleyview_init_clock_gating [i915] So setup probes on both function and see what happen. $ sudo ./perf probe -m i915 -a haswell_init_clock_gating \ -a valleyview_init_clock_gating Added new events: probe:haswell_init_clock_gating (on haswell_init_clock_gating in i915) probe:valleyview_init_clock_gating (on valleyview_init_clock_gating in i915) You can now use it in all perf tools, such as: perf record -e probe:valleyview_init_clock_gating -aR sleep 1 $ sudo ./perf probe -l probe:haswell_init_clock_gating (on haswell_init_clock_gating@gpu/drm/i915/intel_pm.c in i915) probe:valleyview_init_clock_gating (on i915_vga_set_decode:4@gpu/drm/i915/i915_drv.c in i915) As you can see, haswell_init_clock_gating is correctly shown, but valleyview_init_clock_gating is not. With this patch, both events are shown correctly. $ sudo ./perf probe -l probe:haswell_init_clock_gating (on haswell_init_clock_gating@gpu/drm/i915/intel_pm.c in i915) probe:valleyview_init_clock_gating (on valleyview_init_clock_gating@gpu/drm/i915/intel_pm.c in i915) Committer notes: In my case: # perf probe -m i915 -a haswell_init_clock_gating -a valleyview_init_clock_gating Added new events: probe:haswell_init_clock_gating (on haswell_init_clock_gating in i915) probe:valleyview_init_clock_gating (on valleyview_init_clock_gating in i915) You can now use it in all perf tools, such as: perf record -e probe:valleyview_init_clock_gating -aR sleep 1 # perf probe -l probe:haswell_init_clock_gating (on i915_getparam+432@gpu/drm/i915/i915_drv.c in i915) probe:valleyview_init_clock_gating (on __i915_printk+240@gpu/drm/i915/i915_drv.c in i915) # # readelf -SW /lib/modules/4.9.0+/build/vmlinux | egrep -w '.text|Name' [Nr] Name Type Address Off Size ES Flg Lk Inf Al [ 1] .text PROGBITS ffffffff81000000 200000 822fd3 00 AX 0 0 4096 # So both are b0rked, now with the fix: # perf probe -m i915 -a haswell_init_clock_gating -a valleyview_init_clock_gating Added new events: probe:haswell_init_clock_gating (on haswell_init_clock_gating in i915) probe:valleyview_init_clock_gating (on valleyview_init_clock_gating in i915) You can now use it in all perf tools, such as: perf record -e probe:valleyview_init_clock_gating -aR sleep 1 # perf probe -l probe:haswell_init_clock_gating (on haswell_init_clock_gating@gpu/drm/i915/intel_pm.c in i915) probe:valleyview_init_clock_gating (on valleyview_init_clock_gating@gpu/drm/i915/intel_pm.c in i915) # Both looks correct. 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> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/148411436777.9978.1440275861947194930.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-26perf scripting: Avoid leaking the scripting_context variableArnaldo Carvalho de Melo
commit cf346d5bd4b9d61656df2f72565c9b354ef3ca0d upstream. Both register_perl_scripting() and register_python_scripting() allocate this variable, fix it by checking if it already was. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 7e4b21b84c43 ("perf/scripts: Add Python scripting engine") Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31perf symbols: Fixup symbol sizes before picking best onesArnaldo Carvalho de Melo
commit 432746f8e0b6a82ba832b771afe31abd51af6752 upstream. When we call symbol__fixup_duplicate() we use algorithms to pick the "best" symbols for cases where there are various functions/aliases to an address, and those check zero size symbols, which, before calling symbol__fixup_end() are _all_ symbols in a just parsed kallsyms file. So first fixup the end, then fixup the duplicates. Found while trying to figure out why 'perf test vmlinux' failed, see the output of 'perf test -v vmlinux' to see cases where the symbols picked as best for vmlinux don't match the ones picked for kallsyms. Cc: Anton Blanchard <anton@samba.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 694bf407b061 ("perf symbols: Add some heuristics for choosing the best duplicate symbol") Link: http://lkml.kernel.org/n/tip-rxqvdgr0mqjdxee0kf8i2ufn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31perf symbols: Check symbol_conf.allow_aliases for kallsyms loading tooArnaldo Carvalho de Melo
commit c97b40e4d15f13a36cd037d598e45cbe9e1e5757 upstream. We can allow aliases to be kept, but we were checking this just when loading vmlinux files, be consistent, do it for any symbol table loading code that calls symbol__fixup_duplicate() by making this function check .allow_aliases instead. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 680d926a8cb0 ("perf symbols: Allow symbol alias when loading map for symbol name") Link: http://lkml.kernel.org/n/tip-z0avp0s6cfjckc4xj3pdfjdz@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31perf stat: Fix interval output valuesJiri Olsa
commit 51fd2df1e882a3c2a3f4b6c9ff243a93c9046dba upstream. We broke interval data displays with commit: 3f416f22d1e2 ("perf stat: Do not clean event's private stats") This commit removed stats cleaning, which is important for '-r' option to carry counters data over the whole run. But it's necessary to clean it for interval mode, otherwise the displayed value is avg of all previous values. Before: $ perf stat -e cycles -a -I 1000 record # time counts unit events 1.000240796 75,216,287 cycles 2.000512791 107,823,524 cycles $ perf stat report # time counts unit events 1.000240796 75,216,287 cycles 2.000512791 91,519,906 cycles Now: $ perf stat report # time counts unit events 1.000240796 75,216,287 cycles 2.000512791 107,823,524 cycles Notice the second value being bigger (91,.. < 107,..). This could be easily verified by using perf script which displays raw stat data: $ perf script CPU THREAD VAL ENA RUN TIME EVENT 0 -1 23855779 1000209530 1000209530 1000240796 cycles 1 -1 33340397 1000224964 1000224964 1000240796 cycles 2 -1 15835415 1000226695 1000226695 1000240796 cycles 3 -1 2184696 1000228245 1000228245 1000240796 cycles 0 -1 97014312 2000514533 2000514533 2000512791 cycles 1 -1 46121497 2000543795 2000543795 2000512791 cycles 2 -1 32269530 2000543566 2000543566 2000512791 cycles 3 -1 7634472 2000544108 2000544108 2000512791 cycles The sum of the first 4 values is the first interval aggregated value: 23855779 + 33340397 + 15835415 + 2184696 = 75,216,287 The sum of the second 4 values minus first value is the second interval aggregated value: 97014312 + 46121497 + 32269530 + 7634472 - 75216287 = 107,823,524 Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1454485436-20639-1-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28perf intel-pt: Fix MTC timestamp calculation for large MTC periodsAdrian Hunter
commit 3bccbe20f6d188ce7b00326e776b745cfd35b10a upstream. The MTC packet provides a 8-bit slice of CTC which is related to TSC by the TMA packet, however the TMA packet only provides the lower 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC provided by the TMA packet. Fix-up the last_mtc calculated from the TMA packet by copying the missing bits from the current MTC assuming the least difference between the two, and that the current MTC comes after last_mtc. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1475062896-22274-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28perf intel-pt: Fix estimated timestamps for cycle-accurate modeAdrian Hunter
commit 51ee6481fa8e879cc942bcc1b0af713e158b7a98 upstream. In cycle-accurate mode, timestamps can be calculated from CYC packets. The decoder also estimates timestamps based on the number of instructions since the last timestamp. For that to work in cycle-accurate mode, the instruction count needs to be reset to zero when a timestamp is calculated from a CYC packet, but that wasn't happening, so fix it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1475062896-22274-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28perf intel-pt: Fix snapshot overlap detection decoder errorsAdrian Hunter
commit 810c398bc09b2f2dfde52a7d2483a710612c5fb8 upstream. Fix occasional decoder errors decoding trace data collected in snapshot mode. Snapshot mode can take successive snapshots of trace which might overlap. The decoder checks whether there is an overlap but only looks at the current and previous buffer. However buffers that do not contain synchronization (i.e. PSB) packets cannot be decoded or used for overlap checking. That means the decoder actually needs to check overlaps between the current buffer and the previous buffer that contained usable data. Make that change. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Link: http://lkml.kernel.org/r/1474641528-18776-10-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-04perf tools: handle spaces in file names obtained from /proc/pid/mapsMarcin Ślusarz
commit 89fee59b504f86925894fcc9ba79d5c933842f93 upstream. Steam frequently puts game binaries in folders with spaces. Note: "(deleted)" markers are now treated as part of the file name. Signed-off-by: Marcin Ślusarz <marcin.slusarz@gmail.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Fixes: 6064803313ba ("perf tools: Use sscanf for parsing /proc/pid/maps") Link: http://lkml.kernel.org/r/20160119190303.GA17579@marcin-Inspiron-7720 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-04perf evlist: Reference count the cpu and thread maps at set_maps()Arnaldo Carvalho de Melo
commit a55e5663761366fb883f6f25375dd68bc958b9db upstream. We were dropping the reference we possibly held but not obtaining one for the new maps, which we will drop at perf_evlist__delete(), fix it. This was caught by Steven Noonan in some of the machines which would produce this output when caught by glibc debug mechanisms: $ sudo perf test 21 21: Test object code reading :*** Error in `perf': corrupted double-linked list: 0x00000000023ffcd0 *** ======= Backtrace: ========= /usr/lib/libc.so.6(+0x72055)[0x7f25be0f3055] /usr/lib/libc.so.6(+0x779b6)[0x7f25be0f89b6] /usr/lib/libc.so.6(+0x7a0ed)[0x7f25be0fb0ed] /usr/lib/libc.so.6(__libc_calloc+0xba)[0x7f25be0fceda] perf(parse_events_lex_init_extra+0x38)[0x4cfff8] perf(parse_events+0x55)[0x4a0615] perf(perf_evlist__config+0xcf)[0x4eeb2f] perf[0x479f82] perf(test__code_reading+0x1e)[0x47ad4e] perf(cmd_test+0x5dd)[0x46452d] perf[0x47f4e3] perf(main+0x603)[0x42c723] /usr/lib/libc.so.6(__libc_start_main+0xf0)[0x7f25be0a1610] perf(_start+0x29)[0x42c859] Further investigation using valgrind led to the reference count imbalance fixed in this patch. Reported-and-Tested-by: Steven Noonan <steven@uplinklabs.net> Report-Link: http://lkml.kernel.org/r/CAKbGBLjC2Dx5vshxyGmQkcD+VwiAQLbHoXA9i7kvRB2-2opHZQ@mail.gmail.com Cc: Adrian Hunter <adrian.hunter@intel.com> 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: f30a79b012e5 ("perf tools: Add reference counting for cpu_map object") Link: http://lkml.kernel.org/n/tip-j0u1bdhr47sa511sgg76kb8h@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-04perf intel-pt: Fix segfault tracing transactionsAdrian Hunter
commit 1342e0b7a6c1a060c593037fbac9f4b717f1cb3b upstream. Tracing a workload that uses transactions gave a seg fault as follows: perf record -e intel_pt// workload perf report Program received signal SIGSEGV, Segmentation fault. 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) at util/intel-pt.c:929 929 ptq->last_branch_rb->nr = 0; (gdb) p ptq->last_branch_rb $1 = (struct branch_stack *) 0x0 (gdb) up 1148 intel_pt_reset_last_branch_rb(ptq); (gdb) l 1143 if (ret) 1144 pr_err("Intel Processor Trace: failed to deliver transaction event 1145 ret); 1146 1147 if (pt->synth_opts.callchain) 1148 intel_pt_reset_last_branch_rb(ptq); 1149 1150 return ret; 1151 } 1152 (gdb) p pt->synth_opts.callchain $2 = true (gdb) (gdb) bt #0 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) #1 0x000000000054c1e0 in intel_pt_synth_transaction_sample (ptq=0x1a36110) #2 0x000000000054c5b2 in intel_pt_sample (ptq=0x1a36110) Caused by checking the 'callchain' flag when it should have been the 'last_branch' flag. Fix that. Reported-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Fixes: f14445ee72c5 ("perf intel-pt: Support generating branch stack") Link: http://lkml.kernel.org/r/1460977068-11566-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12perf tools: Fix python extension buildJiri Olsa
commit 67d5268908283c187e0a460048a423256c2fb288 upstream. The util/python-ext-sources file contains source files required to build the python extension relative to $(srctree)/tools/perf, Such a file path $(FILE).c is handed over to the python extension build system, which builds the final object in the $(PYTHON_EXTBUILD)/tmp/$(FILE).o path. After the build is done all files from $(PYTHON_EXTBUILD)lib/ are carried as the result binaries. Above system fails when we add source file relative to ../lib, which we do for: ../lib/bitmap.c ../lib/find_bit.c ../lib/hweight.c ../lib/rbtree.c All above objects will be built like: $(PYTHON_EXTBUILD)/tmp/../lib/bitmap.c $(PYTHON_EXTBUILD)/tmp/../lib/find_bit.c $(PYTHON_EXTBUILD)/tmp/../lib/hweight.c $(PYTHON_EXTBUILD)/tmp/../lib/rbtree.c which accidentally happens to be final library path: $(PYTHON_EXTBUILD)/lib/ Changing setup.py to pass full paths of source files to Extension build class and thus keep all built objects under $(PYTHON_EXTBUILD)tmp directory. Reported-by: Jeff Bastian <jbastian@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Josh Boyer <jwboyer@fedoraproject.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20160227201350.GB28494@krava.redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12perf tools: Fix checking asprintf return valueWang Nan
commit 26dee028d365fbc0e3326606a8520260b4462381 upstream. According to man pages, asprintf returns -1 when failure. This patch fixes two incorrect return value checker. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Cody P Schafer <dev@codyps.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kirill Smelkov <kirr@nexedi.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Fixes: ffeb883e5662 ("perf tools: Show proper error message for wrong terms of hw/sw events") Link: http://lkml.kernel.org/r/1455882283-79592-5-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12perf tools: Dont stop PMU parsing on alias parse errorAndi Kleen
commit 940db6dcd3f4659303fdf6befe7416adc4d24118 upstream. When an error happens during alias parsing currently the complete parsing of all attributes of the PMU is stopped. This is breaks old perf on a newer kernel that may have not-yet-know alias attributes (such as .scale or .per-pkg). Continue when some attribute is unparseable. This is IMHO a stable candidate and should be backported to older versions to avoid problems with newer kernels. v2: Print warnings when something goes wrong. v3: Change warning to debug output Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/1455749095-18358-1-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03perf stat: Do not clean event's private statsJiri Olsa
commit 3f416f22d1e21709a631189ba169f76fd267b374 upstream. Mel reported stddev reporting was broken due to following commit: 106a94a0f8c2 ("perf stat: Introduce read_counters function") This commit merged interval and overall counters reading into single read_counters function. The old interval code cleaned the stddev data for some reason (it's never displayed in interval mode) and the mentioned commit kept on cleaning the stddev data in merged function, which resulted in the stddev not being displayed. Removing the wrong stddev data cleanup init_stats call. Reported-and-Tested-by: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Fixes: 106a94a0f8c2 ("perf stat: Introduce read_counters function") Link: http://lkml.kernel.org/r/1453290995-18485-4-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25perf kvm record/report: 'unprocessable sample' error while ↵Ravi Bangoria
recording/reporting guest data commit 3caeaa562733c4836e61086ec07666635006a787 upstream. While recording guest samples in host using perf kvm record, it will populate unprocessable sample error, though samples will be recorded properly. While generating report using perf kvm report, no samples will be processed and same error will populate. We have seen this behaviour with upstream perf(4.4-rc3) on x86 and ppc64 hardware. Reason behind this failure is, when it tries to fetch machine from rb_tree of machines, it fails. As a part of tracing a bug, we figured out that this code was incorrectly refactored in commit 54245fdc3576 ("perf session: Remove wrappers to machines__find"). This patch will change the functionality such that if it can't fetch machine in first trial, it will create one node of machine and add that to rb_tree. So next time when it tries to fetch same machine from rb_tree, it won't fail. Actually it was the case before refactoring of code in aforementioned commit. This patch is generated from acme perf/core branch. Below I've mention an example that demonstrate the behaviour before and after applying patch. Before applying patch: [Note: One needs to run guest before recording data in host] ravi@ravi-bangoria:~$ ./perf kvm record -a Warning: 5903 unprocessable samples recorded. Do you have a KVM guest running and not using 'perf kvm'? [ perf record: Captured and wrote 1.409 MB perf.data.guest (285 samples) ] ravi@ravi-bangoria:~$ ./perf kvm report --stdio Warning: 5903 unprocessable samples recorded. Do you have a KVM guest running and not using 'perf kvm'? # To display the perf.data header info, please use --header/--header-only options. # # Total Lost Samples: 0 # # Samples: 285 of event 'cycles' # Event count (approx.): 88715406 # # Overhead Command Shared Object Symbol # ........ ....... ............. ...... # # (For a higher level overview, try: perf report --sort comm,dso) # After applying patch: ravi@ravi-bangoria:~$ ./perf kvm record -a [ perf record: Captured and wrote 1.188 MB perf.data.guest (17 samples) ] ravi@ravi-bangoria:~$ ./perf kvm report --stdio # To display the perf.data header info, please use --header/--header-only options. # # Total Lost Samples: 0 # # Samples: 17 of event 'cycles' # Event count (approx.): 700746 # # Overhead Command Shared Object Symbol # ........ ....... ................ ...................... # 34.19% :5758 [unknown] [g] 0xffffffff818682ab 22.79% :5758 [unknown] [g] 0xffffffff812dc7f8 22.79% :5758 [unknown] [g] 0xffffffff818650d0 14.83% :5758 [unknown] [g] 0xffffffff8161a1b6 2.49% :5758 [unknown] [g] 0xffffffff818692bf 0.48% :5758 [unknown] [g] 0xffffffff81869253 0.05% :5758 [unknown] [g] 0xffffffff81869250 Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Fixes: 54245fdc3576 ("perf session: Remove wrappers to machines__find") Link: http://lkml.kernel.org/r/1449471302-11283-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25perf tools: tracepoint_error() can receive e=NULL, robustify itAdrian Hunter
commit ec183d22cc284a7a1e17f0341219d8ec8ca070cc upstream. Fixes segmentation fault using, for instance: (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64 [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. 0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 (gdb) bt #0 0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 #1 0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:433 #2 0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:498 #3 0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:936 #4 0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391 #5 0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361 #6 0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401 #7 0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253 #8 0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364 #9 0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664 #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539 #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264 #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390 #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451 #14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495 #15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618 (gdb) Intel PT attempts to find the sched:sched_switch tracepoint but that seg faults if tracefs is not readable, because the error reporting structure is null, as errors are not reported when automatically adding tracepoints. Fix by checking before using. Committer note: This doesn't take place in a kernel that supports perf_event_attr.context_switch, that is the default way that will be used for tracking context switches, only in older kernels, like 4.2, in a machine with Intel PT (e.g. Broadwell) for non-priviledged users. Further info from a similar patch by Wang: The error is in tracepoint_error: it assumes the 'e' parameter is valid. However, there are many situation a parse_event() can be called without parse_events_error. See result of $ grep 'parse_events(.*NULL)' ./tools/perf/ -r' Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Tong Zhang <ztong@vt.edu> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 196581717d85 ("perf tools: Enhance parsing events tracepoint error output") Link: http://lkml.kernel.org/r/1453809921-24596-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-16perf list: Robustify event printing routineArnaldo Carvalho de Melo
When a43eec304259 ("bpf: introduce bpf_perf_event_output() helper") added PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw array that wasn't initialized, thus set to NULL, fix print_symbol_events() to check for that case so that we don't crash if this happens again. (gdb) bt #0 __match_glob (ignore_space=false, pat=<optimized out>, str=<optimized out>) at util/string.c:198 #1 strglobmatch (str=<optimized out>, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252 #2 0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 <event_symbols_sw+160>, max=11, name_only=false, event_glob=0x7fffffffe61d "stall") at util/parse-events.c:1615 #3 print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675 #4 0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=<optimized out>) at builtin-list.c:68 #5 0x00000000004788a5 in run_builtin (p=p@entry=0x871758 <commands+120>, argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370 #6 0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429 #7 run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473 #8 main (argc=2, argv=0x7fffffffe390) at perf.c:588 (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT] $4 = {symbol = 0x0, alias = 0x0} (gdb) A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar <mingo@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@kernel.org> 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-57wysblcjfrseb0zg5u7ek10@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-16perf list: Add support for PERF_COUNT_SW_BPF_OUTArnaldo Carvalho de Melo
When PERF_COUNT_SW_BPF_OUTPUT was added to the kernel we should've added it to tools/perf, where it is used just to list events. This ended up causing a segfault in commands like "perf list stall". Fix it by adding that new software counter. A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar <mingo@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@kernel.org> 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-uya354upi3eprsey6mi5962d@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-07perf buildid-list: Show running kernel build id fixMichael Petlan
The --kernel option of perf buildid-list tool should show the running kernel buildid. The functionality has been lost during other changes of the related code. The build_id__sprintf() function should return length of the build-id string, but it was the length of the build-id raw data instead. Due to that, some return value checking caused that the final string was not printed out. With this patch the build_id__sprintf() returns the correct value, so the --kernel option works again. Before: # perf buildid-list --kernel # After: # perf buildid-list --kernel 972c1edab5bdc06cc224af45d510af662a3c6972 # Signed-off-by: Michael Petlan <mpetlan@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> LPU-Reference: 1448632089.24573.114.camel@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-13perf probe: Clear probe_trace_event when add_probe_trace_event() failsWang Nan
When probing with a glob, errors in add_probe_trace_event() won't be passed to debuginfo__find_trace_events() because it would be modified by probe_point_search_cb(). It causes a segfault if perf fails to find an argument for a probe point matched by the glob. For example: # ./perf probe -v -n 'SyS_dup? oldfd' probe-definition(0): SyS_dup? oldfd symbol:SyS_dup? file:(null) line:0 offset:0 return:0 lazy:(null) parsing arg: oldfd into oldfd 1 arguments Looking at the vmlinux_path (7 entries long) Using /lib/modules/4.3.0-rc4+/build/vmlinux for symbols Open Debuginfo file: /lib/modules/4.3.0-rc4+/build/vmlinux Try to find probe point from debuginfo. Matched function: SyS_dup3 found inline addr: 0xffffffff812095c0 Probe point found: SyS_dup3+0 Searching 'oldfd' variable in context. Converting variable oldfd into trace event. oldfd type is long int. found inline addr: 0xffffffff812096d4 Probe point found: SyS_dup2+36 Searching 'oldfd' variable in context. Failed to find 'oldfd' in this function. Matched function: SyS_dup3 Probe point found: SyS_dup3+0 Searching 'oldfd' variable in context. Converting variable oldfd into trace event. oldfd type is long int. Matched function: SyS_dup2 Probe point found: SyS_dup2+0 Searching 'oldfd' variable in context. Converting variable oldfd into trace event. oldfd type is long int. Found 4 probe_trace_events. Opening /sys/kernel/debug/tracing//kprobe_events write=1 Writing event: p:probe/SyS_dup3 _text+2135488 oldfd=%di:s64 Segmentation fault (core dumped) # This patch ensures that add_probe_trace_event() doesn't touches tf->ntevs and tf->tevs if those functions fail. After the patch: # perf probe 'SyS_dup? oldfd' Failed to find 'oldfd' in this function. Added new events: probe:SyS_dup3 (on SyS_dup? with oldfd) probe:SyS_dup3_1 (on SyS_dup? with oldfd) probe:SyS_dup2 (on SyS_dup? with oldfd) You can now use it in all perf tools, such as: perf record -e probe:SyS_dup2 -aR sleep 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: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447417761-156094-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-13perf probe: Fix memory leaking on failure by clearing all probe_trace_eventsMasami Hiramatsu
Fix memory leaking on the debuginfo__find_trace_events() failure path which frees an array of probe_trace_events but doesn't clears all the allocated sub-structures and strings. So, before doing zfree(tevs), clear all the array elements which may have allocated resources. Reported-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447417761-156094-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-13perf buildid-list: Requires ordered eventsAdrian Hunter
'perf buildid-list' processes events to determine hits (i.e. with-hits option). That may not work if events are not sorted in order. i.e. MMAP events must be processed before the samples that depend on them so that sample processing can 'hit' the DSO to which the MMAP refers. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1447408112-1920-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-13perf symbols: Fix dso lookup by long name and missing buildidsAdrian Hunter
Commit 4598a0a6d22f ("perf symbols: Improve DSO long names lookup speed with rbtree") Added a tree to lookup dsos by long name. That tree gets corrupted whenever a dso long name is changed because the tree is not updated. One effect of that is buildid-list does not work with the 'with-hits' option because dso lookup fails and results in two structs for the same dso. The first has the buildid but no hits, the second has hits but no buildid. e.g. Before: $ tools/perf/perf record ls arch certs CREDITS Documentation firmware include ipc Kconfig lib Makefile net REPORTING-BUGS scripts sound usr block COPYING crypto drivers fs init Kbuild kernel MAINTAINERS mm README samples security tools virt [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.012 MB perf.data (11 samples) ] $ tools/perf/perf buildid-list 574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms] 30c94dc66a1fe95180c3d68d2b89e576d5ae213c /lib/x86_64-linux-gnu/libc-2.19.so $ tools/perf/perf buildid-list -H 574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms] 0000000000000000000000000000000000000000 /lib/x86_64-linux-gnu/libc-2.19.so After: $ tools/perf/perf buildid-list -H 574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms] 30c94dc66a1fe95180c3d68d2b89e576d5ae213c /lib/x86_64-linux-gnu/libc-2.19.so The fix is to record the root of the tree on the dso so that dso__set_long_name() can update the tree when the long name changes. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Douglas Hatch <doug.hatch@hp.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Scott J Norton <scott.norton@hp.com> Cc: Waiman Long <Waiman.Long@hp.com> Fixes: 4598a0a6d22f ("perf symbols: Improve DSO long names lookup speed with rbtree") Link: http://lkml.kernel.org/r/1447408112-1920-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-12perf symbols: Allow forcing reading of non-root owned files by rootArnaldo Carvalho de Melo
When the root user tries to read a file owned by some other user we get: # ls -la perf.data -rw-------. 1 acme acme 20032 Nov 12 15:50 perf.data # perf report File perf.data not owned by current user or root (use -f to override) # perf report -f | grep -v ^# | head -2 30.96% ls [kernel.vmlinux] [k] do_set_pte 28.24% ls libc-2.20.so [.] intel_check_word # That wasn't happening when the symbol code tried to read a JIT map, where the same check was done but no forcing was possible, fix it. Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com> Tested-by: Brendan Gregg <brendan.d.gregg@gmail.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://permalink.gmane.org/gmane.linux.kernel.perf.user/2380 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-12perf symbols: Rebuild rbtree when adjusting symbols for kcoreAdrian Hunter
Normally symbols are read from the DSO and adjusted, if need be, so that the symbol start matches the file offset in the DSO file (we want the file offset because that is what we know from MMAP events). That is done by dso__load_sym() which inserts the symbols *after* adjusting them. In the case of kcore, the symbols have been read from kallsyms and the symbol start is the memory address. The symbols have to be adjusted to match the kcore file offsets. dso__split_kallsyms_for_kcore() does that, but now the adjustment is being done *after* the symbols have been inserted. It appears dso__split_kallsyms_for_kcore() was assuming that changing the symbol start would not change the order in the rbtree - which is, of course, not guaranteed. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Wang Nan <wangnan0@huawei.com> 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/563CB241.2090701@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-11perf probe: Verify parameters in two functionsWang Nan
On kernel with only one out of CONFIG_KPROBE_EVENTS and CONFIG_UPROBE_EVENTS enabled, 'perf probe -d' causes a segfault because perf_del_probe_events() calls probe_file__get_events() with a negative fd. This patch fixes it by adding parameter validation at the entry of probe_file__get_events() and probe_file__get_rawlist(). Since they are both non-static public functions (in .h file), parameter verifying is required. v1 -> v2: Verify fd at the head of probe_file__get_rawlist() instead of checking at call site (suggested by Masami and Arnaldo at [1,2]). [1] http://lkml.kernel.org/r/50399556C9727B4D88A595C8584AAB37526048E3@GSjpTKYDCembx32.service.hitachi.net [2] http://lkml.kernel.org/r/20151105155830.GV13236@kernel.org Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446803415-83382-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-11perf session: Add missing newlines to some pr_err() callsArnaldo Carvalho de Melo
Before: [acme@zoo linux]$ perf evlist WARNING: The perf.data file's data size field is 0 which is unexpected. Was the 'perf record' command properly terminated? non matching sample_type[acme@zoo linux]$ After: [acme@zoo linux]$ perf evlist WARNING: The perf.data file's data size field is 0 which is unexpected. Was the 'perf record' command properly terminated? non matching sample_type [acme@zoo linux]$ 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-wscok3a2s7yrj8156oc2r6qe@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-11perf annotate: Support full source file paths for srcline fixMichael Petlan
The --full-paths option did not show the full source file paths in the 'perf annotate' tool, because the value of the option was not propagated into the related functions. With this patch the value of the --full-paths option is known to the function that composes the srcline string, so it prints the full path when necessary. Committer Note: This affects annotate when the --print-line option is used: # perf annotate -h 2>&1 | grep print-line -l, --print-line print matching source lines (may be slow) Looking just at the lines that should be affected by this change: Before: # perf annotate --print-line --full-paths --stdio fput | grep '\.[ch]:[0-9]\+' 94.44 atomic64_64.h:114 5.56 file_table.c:265 file_table.c:265 5.56 : ffffffff81219a00: callq ffffffff81769360 <__fentry__> atomic64_64.h:114 94.44 : ffffffff81219a05: lock decq 0x38(%rdi) After: # perf annotate --print-line --full-paths --stdio fput | grep '\.[ch]:[0-9]\+' 94.44 /home/git/linux/arch/x86/include/asm/atomic64_64.h:114 5.56 /home/git/linux/fs/file_table.c:265 /home/git/linux/fs/file_table.c:265 5.56 : ffffffff81219a00: callq ffffffff81769360 <__fentry__> /home/git/linux/arch/x86/include/asm/atomic64_64.h:114 94.44 : ffffffff81219a05: lock decq 0x38(%rdi) # Signed-off-by: Michael Petlan <mpetlan@redhat.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2365 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06perf test: Add 'perf test BPF'Wang Nan
This patch adds BPF testcase for testing BPF event filtering. By utilizing the result of 'perf test LLVM', this patch compiles the eBPF sample program then test its ability. The BPF script in 'perf test LLVM' lets only 50% samples generated by epoll_pwait() to be captured. This patch runs that system call for 111 times, so the result should contain 56 samples. 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: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06perf bpf: Improve BPF related error messagesWang Nan
A series of bpf loader related error codes were introduced to help error reporting. Functions were improved to return these new error codes. Functions which return pointers were adjusted to encode error codes into return value using the ERR_PTR() interface. bpf_loader_strerror() was improved to convert these error messages to strings. It checks the error codes and calls libbpf_strerror() and strerror_r() accordingly, so caller don't need to consider checking the range of the error code. In bpf__strerror_load(), print kernel version of running kernel and the object's 'version' section to notify user how to fix his/her program. v1 -> v2: Use macro for error code. Fetch error message based on array index, eliminate for-loop. Print version strings. Before: # perf record -e ./test_kversion_nomatch_program.o sleep 1 event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP After: # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ 'version' (4.4.0) doesn't match running kernel (4.3.0) SKIP Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446818289-87444-1-git-send-email-wangnan0@huawei.com [ Add 'static inline' to bpf__strerror_prepare_load() when LIBBPF is disabled ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06perf tools: Make fetch_kernel_version() publicly availableWang Nan
There are 2 places in llvm-utils.c which find kernel version information through uname. This patch extracts the uname related code into a fetch_kernel_version() function and puts it into util.h so it can be reused. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446818135-87310-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06bpf tools: Improve libbpf error reportingWang Nan
In this patch, a series of libbpf specific error numbers and libbpf_strerror() are introduced to help reporting errors. Functions are updated to pass correct the error number through the CHECK_ERR() macro. All users of bpf_object__open{_buffer}() and bpf_program__title() in perf are modified accordingly. In addition, due to the error codes changing, bpf__strerror_load() is also modified to use them. bpf__strerror_head() is also changed accordingly so it can parse libbpf errors. bpf_loader_strerror() is introduced for that purpose, and will be improved by the following patch. load_program() is improved not to dump log buffer if it is empty. log buffer is also used to deduce whether the error was caused by an invalid program or other problem. v1 -> v2: - Using macro for error code. - Fetch error message based on array index, eliminate for-loop. - Use log buffer to detect the reason of failure. 3 new error code are introduced to replace LIBBPF_ERRNO__LOAD. In v1: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_big_program.o ls event syntax error: './test_big_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP In v2: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Kernel verifier blocks program loading SKIP # perf record -e ./test_kversion_nomatch_program.o event syntax error: './test_kversion_nomatch_program.o' \___ Incorrect kernel version SKIP (Will be further improved by following patches) # perf record -e ./test_big_program.o event syntax error: './test_big_program.o' \___ Program too big SKIP Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06perf probe: Cleanup find_perf_probe_point_from_map to reduce redundancyMasami Hiramatsu
In find_perf_probe_point_from_map(), the 'ret' variable is initialized with -ENOENT but overwritten by the return code of kernel_get_symbol_address_by_name(), and after that it is re-initialized with -ENOENT again. Setting ret=-ENOENT twice looks a bit redundant. This avoids the overwriting and just returns -ENOENT if some error happens to simplify the code. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-ufp1zgbktzmttcputozneomd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06perf annotate: Inform the user about objdump failures in --stdioAndi Kleen
When the browser fails to annotate it is difficult for users to find out what went wrong. Add some errors for objdump failures that are displayed in the UI. Note it would be even better to handle these errors smarter, like falling back to the binary when the debug info is somehow corrupted. But for now just giving a better error is an improvement. Committer note: This works for --stdio, where errors just scroll by the screen: # perf annotate --stdio intel_idle Failure running objdump --start-address=0xffffffff81418290 --stop-address=0xffffffff814183ae -l -d --no-show-raw -S -C /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1 2>/dev/null|grep -v /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1|expand Percent | Source code & Disassembly of vmlinux for cycles:pp ------------------------------------------------------------------ And with that one can use that command line to try to find out more about what happened instead of getting a blank screen, an improvement. We need tho to improve this further to get it to work with other UIs, like --tui and --gtk, where it continues showing a blank screen, no messages, as the pr_err() used is enough just for --stdio. Signed-off-by: Andi Kleen <ak@linux.intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1446779167-18949-1-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>