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2015-09-28perf tools: Show proper error message for wrong terms of hw/sw eventsHe Kuang4-24/+45
Show proper error message and show valid terms when wrong config terms is specified for hw/sw type perf events. This patch makes the original error format function formats_error_string() more generic, which only outputs the static config terms for hw/sw perf events, and prepends pmu formats for pmu events. Before this patch: $ perf record -e 'cpu-clock/freqx=200/' -a sleep 1 invalid or unsupported event: 'cpu-clock/freqx=200/' Run 'perf list' for a list of valid events usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events After this patch: $ perf record -e 'cpu-clock/freqx=200/' -a sleep 1 event syntax error: 'cpu-clock/freqx=200/' \___ unknown term valid terms: config,config1,config2,name,period,freq,branch_type,time,call-graph,stack-size Run 'perf list' for a list of valid events usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events Signed-off-by: He Kuang <hekuang@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1443412336-120050-2-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf tools: Adds the config_term callback for different type eventsHe Kuang1-12/+26
Currently, function config_term() is used for checking config terms of all types of events, while unknown terms is not reported as an error because pmu events have valid terms in sysfs. But this is wrong when unknown terms are specificed to hw/sw events. This patch Adds the config_term callback so we can use separate check routines for each type of events. Signed-off-by: He Kuang <hekuang@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1443412336-120050-1-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf intel-pt: Add mispred-all config option to aid use with autofdoAdrian Hunter2-0/+43
autofdo incorrectly expects branch flags to include either mispred or predicted. In fact mispred = predicted = 0 is valid and means the flags are not supported, which they aren't by Intel PT. To make autofdo work, add a config option which will cause Intel PT decoder to set the mispred flag on all branches. Below is an example of using Intel PT with autofdo. The example is also added to the Intel PT documentation. It requires autofdo (https://github.com/google/autofdo) and gcc version 5. The bubble sort example is from the AutoFDO tutorial (https://gcc.gnu.org/wiki/AutoFDO/Tutorial) amended to take the number of elements as a parameter. $ gcc-5 -O3 sort.c -o sort_optimized $ ./sort_optimized 30000 Bubble sorting array of 30000 elements 2254 ms $ cat ~/.perfconfig [intel-pt] mispred-all $ perf record -e intel_pt//u ./sort 3000 Bubble sorting array of 3000 elements 58 ms [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 3.939 MB perf.data ] $ perf inject -i perf.data -o inj --itrace=i100usle --strip $ ./create_gcov --binary=./sort --profile=inj --gcov=sort.gcov -gcov_version=1 $ gcc-5 -O3 -fauto-profile=sort.gcov sort.c -o sort_autofdo $ ./sort_autofdo 30000 Bubble sorting array of 30000 elements 2155 ms Note there is currently no advantage to using Intel PT instead of LBR, but that may change in the future if greater use is made of the data. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-26-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf inject: Add --strip option to strip out non-synthesized eventsAdrian Hunter2-0/+95
Add a new option --strip which is used with --itrace to strip out non-synthesized events. This results in a perf.data file that is simpler for external tools to parse. In particular, this can be used to prepare a perf.data file for consumption by autofdo. A subsequent patch makes a change to Intel PT also to enable use with autofdo and gives an example of that use. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-25-git-send-email-adrian.hunter@intel.com [ Made it use perf_evlist__remove() + perf_evsel__delete() ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf inject: Remove more aux-related stuff when processing instruction tracesAdrian Hunter1-1/+28
perf inject can process instruction traces (using the --itrace option) which removes aux-related events and replaces them with the requested synthesized events. However there are still some leftovers, namely PERF_RECORD_ITRACE_START events and the original evsel (selected event) e.g. intel_pt// For the sake of completeness, remove them too. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-24-git-send-email-adrian.hunter@intel.com [ Made it use perf_evlist__remove() + perf_evsel__delete() ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf evlist: Add perf_evlist__remove()Adrian Hunter2-0/+8
Add a counterpart to perf_evlist__add() that does the opposite and deletes the evsel. This will be used by perf inject to remove unwanted evsels. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-23-git-send-email-adrian.hunter@intel.com [ Renamed it from perf_evlist__del() to perf_evlist__remove() and removed the perf_evsel__delete() call ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf evlist: Add perf_evlist__id2evsel_strict()Adrian Hunter2-0/+17
perf_evlist__id2evsel_strict() is the same as perf_evlist__id2evsel() except that it ensures that the id must match. This will be used by perf inject to find a specific evsel that is to be deleted, hence the need to match exactly. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-22-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf script: Make scripting_max_stack value allow for synthesized callchainsAdrian Hunter1-0/+4
perf script has a setting to set the maximum stack depth when processing callchains. The setting defaults to the hard-coded maximum definition PERF_MAX_STACK_DEPTH which is 127. It is possible, when processing instruction traces, to synthesize callchains. Synthesized callchains do not have the kernel size limitation and are whatever size the user requests, although validation presently prevents the user requested a value greater that 1024. The default value is 16. To allow for synthesized callchains, make the scripting_max_stack value at least the same size as the synthesized callchain size. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-21-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf scripting python: Allow for max_stack greater than PERF_MAX_STACK_DEPTHAdrian Hunter3-2/+4
Use the scripting_max_stack value to allow for values greater than PERF_MAX_STACK_DEPTH. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-20-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf script: Add a setting for maximum stack depthAdrian Hunter2-3/+5
Add a setting for maximum stack depth in preparation for allowing for synthesized callchains. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-19-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf hists: Allow for max_stack greater than PERF_MAX_STACK_DEPTHAdrian Hunter2-2/+5
Use the max_stack value instead of PERF_MAX_STACK_DEPTH so that arbitrary-sized callchains can be supported. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-17-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf report: Make max_stack value allow for synthesized callchainsAdrian Hunter1-0/+4
perf report has an option (--max-stack) to set the maximum stack depth when processing callchains. The option defaults to the hard-coded maximum definition PERF_MAX_STACK_DEPTH which is 127. The intention of the option is to allow the user to reduce the processing time by reducing the amount of the callchain that is processed. It is also possible, when processing instruction traces, to synthesize callchains. Synthesized callchains do not have the kernel size limitation and are whatever size the user requests, although validation presently prevents the user requested a value greater that 1024. The default value is 16. To allow for synthesized callchains, make the max_stack value at least the same size as the synthesized callchain size. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-16-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf intel-pt: Support generating branch stackAdrian Hunter2-0/+125
Add support for generating branch stack context for PT samples. The decoder reports a configurable number of branches as branch context for each sample. Internally it keeps track of them by using a simple sliding window. We also flush the last branch buffer on each sample to avoid overlapping intervals. This is useful for: - Reporting accurate basic block edge frequencies through the perf report branch view - Using with --branch-history to get the wider context of samples - Other users of LBRs Also the Documentation is updated. Examples: Record with Intel PT: perf record -e intel_pt//u ls Branch stacks are used by default if synthesized so: perf report --itrace=ile is the same as: perf report --itrace=ile -b Branch history can be requested also: perf report --itrace=igle --branch-history Based-on-patch-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-15-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf intel-pt: Move branch filter logicAdrian Hunter1-3/+3
intel_pt_synth_branch_sample() skips synthesizing if the branch does not match the branch filter. That logic was sitting in the middle of the function but is more efficiently placed at the start of the function, so move it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-14-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf inject: Set branch stack feature flag when synthesizing branch stacksAdrian Hunter1-1/+5
The branch stack feature flag is set by 'perf record' when recording data that contains branch stacks. Consequently, when 'perf inject' synthesizes branch stacks, the feature flag should be set also. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-13-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf report: Skip events with null branch stacksAdrian Hunter1-4/+11
A non-synthesized event might not have a branch stack if branch stacks have been synthesized (using itrace options). An example of that is when Intel PT records sched_switch events for decoding purposes. Those sched_switch events do not have branch stacks even though the Intel PT decoder may be synthesizing other events that do due to the itrace options. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-12-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf report: Also do default setup for synthesized branch stacksAdrian Hunter1-0/+3
The 'perf report' tool will default to displaying branch stacks (-b option) if they are present. Make that also happen for synthesized branch stacks. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-11-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf report: Adjust sample type validation for synthesized branch stacksAdrian Hunter1-0/+3
perf report looks at event sample types to determine if branch stacks have been sampled. Adjust the validation to know about instruction tracing options. This change allows the use of the -b option which otherwise would complain with an error like: Error: Selected -b but no branch data. Did you call perf record without -b? # To display the perf.data header info, # please use --header/--header-only options. # Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-10-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf auxtrace: Add option to synthesize branch stacks on samplesAdrian Hunter3-0/+28
Add AUX area tracing option 'l' to synthesize branch stacks on samples just like sample type PERF_SAMPLE_BRANCH_STACK. This is taken into use by Intel PT in a subsequent patch. Based-on-patch-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-9-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf tools: Add more documentation to export-to-postgresql.py scriptAdrian Hunter1-0/+221
Add some comments to the script and some 'views' to the created database that better illustrate the database structure and how it can be used. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-8-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf session: Warn when AUX data has been lostAdrian Hunter2-0/+11
By default 'perf record' will postprocess the perf.data file to determine build-ids. When that happens, the number of lost perf events is displayed. Make that also happen for AUX events. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-7-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf script: Allow time to be displayed in nanosecondsAdrian Hunter2-1/+10
Add option --ns to display time to 9 decimal places. That is useful in some cases, for example when using Intel PT cycle accurate mode. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-6-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf intel-pt: Make logging slightly more efficientAdrian Hunter2-16/+43
Logging is only used for debugging. Use macros to save calling into the functions only to return immediately when logging is not enabled. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-5-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf intel-pt: Fix potential loop foreverAdrian Hunter1-2/+2
TSC packets contain only 7 bytes of TSC. The 8th byte is assumed to change so infrequently that its value can be inferred. However the logic must cater for a 7 byte wraparound, which it does by adding 1 to the top byte. The existing code was doing that with a while loop even though the addition should only need to be done once. That logic won't work (will loop forever) if TSC wraps around at the 8th byte. Theoretically that would take at least 10 years, unless something else went wrong. And what else could go wrong. Well, if the chunks of trace data are processed out of order, it will make it look like the 7-byte TSC has gone backwards (i.e. wrapped). If that happens 256 times then stuck in the while loop it will be. Fix that by getting rid of the unnecessary while loop. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-4-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf report: Fix sample type validation for synthesized callchainsAdrian Hunter1-0/+6
Processing instruction tracing data (e.g. Intel PT) can synthesize callchains e.g. $ perf record -e intel_pt//u uname $ perf report --stdio --itrace=ige However perf report's callgraph option gets extra validation, so: $ perf report --stdio --itrace=ige -gflat Error: Selected -g or --branch-history but no callchain data. Did you call 'perf record' without -g? # To display the perf.data header info, # please use --header/--header-only options. # Fix the validation to know about instruction tracing options so above command works. A side-effect of the change is that the default option to accumulate the callchain of child functions comes into force. To get the previous behaviour the --no-children option can be used e.g. $ perf report --stdio --itrace=ige -gflat --no-children Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf auxtrace: Fix 'instructions' period of zeroAdrian Hunter3-2/+9
Instruction tracing options (i.e. --itrace) include an option for sampling instructions at an arbitrary period. e.g. --itrace=i10us means make an 'instructions' sample for every 10us of trace. Currently the logic does not distinguish between a period of zero and no period being specified at all, so it gets treated as the default period which is 100000. That doesn't really make sense. Fix it so that zero period is accepted and treated as meaning "as often as possible". In the case of Intel PT that is the same as a period of 1 and a unit of 'instructions' (i.e. --itrace=i1i). Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443186956-18718-2-git-send-email-adrian.hunter@intel.com [ Add a few lines describing this in the Documentation/intel-pt.txt file ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28tools build: Build fixdep helper from perf and basic libsJiri Olsa1-6/+6
Adding the fixdep target into the Makefile.include to ease up building of fixdep helper, that needs to be built before we dive in to the build itself. The user can invoke the fixdep target to build the helper. 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> Link: http://lkml.kernel.org/r/1443004442-32660-8-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf tools: Rename the 'single_dep' target to 'prepare'Jiri Olsa1-10/+10
And use the new 'prepare' target for the $(PERF_IN) target. 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> Link: http://lkml.kernel.org/r/1443004442-32660-7-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28tools build: Add Makefile.includeJiri Olsa1-1/+1
To ease up build framework code setup for users. More shared code will be added in the following patches. 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> Link: http://lkml.kernel.org/r/1443004442-32660-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf tools: Use __map__is_kernel() when synthesizing kernel module mmap recordsArnaldo Carvalho de Melo1-1/+1
Equivalent and removes one more case of using dso->kernel. # perf record -a usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.768 MB perf.data (30 samples) ] Before: [root@zoo ~]# perf script --show-task --show-mmap | head -3 swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffff81000000(0x1f000000) @ 0xffffffff81000000]: x [kernel.kallsyms]_text swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa0000000(0xa000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/acpi/video.ko swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa000a000(0x5000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/i2c/algos/i2c-algo-bit.ko # # perf script --show-task --show-mmap | head -3 swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffff81000000(0x1f000000) @ 0xffffffff81000000]: x [kernel.kallsyms]_text swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa0000000(0xa000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/acpi/video.ko swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa000a000(0x5000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/i2c/algos/i2c-algo-bit.ko # 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> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-b65xe578dwq22mzmmj5y94wr@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf hists browser: Use the map to determine if a DSO is being used as a kernelArnaldo Carvalho de Melo1-10/+14
The map is what should say if an ELF (or some other format) image is being used for some particular purpose, as a kernel, host or guest. 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> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-zufousvfar0710p4qj71c32d@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28perf top: Filter symbols based on __map__is_kernel(map)Arnaldo Carvalho de Melo1-1/+1
Instead of using dso->kernel, this is equivalent at the moment, and helps in reducing the accesses to dso->kernel. 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> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-1pc2v63iphtifovw3bv0bo1v@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-28Merge branch 'linus' into perf/core, to pick up fixes before applying new ↵Ingo Molnar3-43/+20
changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-25perf tools: Fix copying of /proc/kcoreAdrian Hunter1-22/+13
A copy of /proc/kcore containing the kernel text can be made to the buildid cache. e.g. perf buildid-cache -v -k /proc/kcore To workaround objdump limitations, a copy is also made when annotating against /proc/kcore. The copying process stops working from libelf about v1.62 onwards (the problem was found with v1.63). The cause is that a call to gelf_getphdr() in kcore__add_phdr() fails because additional validation has been added to gelf_getphdr(). The use of gelf_getphdr() is a misguided attempt to get default initialization of the Gelf_Phdr structure. That should not be necessary because every member of the Gelf_Phdr structure is subsequently assigned. So just remove the call to gelf_getphdr(). Similarly, a call to gelf_getehdr() in gelf_kcore__init() can be removed also. Committer notes: Note to stable@kernel.org, from Adrian in the cover letter for this patchkit: The "Fix copying of /proc/kcore" problem goes back to v3.13 if you think it is important enough for stable. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: stable@kernel.org Link: http://lkml.kernel.org/r/1443089122-19082-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-25perf intel-pt: Remove no_force_psb from documentationAdrian Hunter1-15/+0
no_force_psb was dropped as a late change to the kernel driver. Consequently, remove it from the documentation. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443089122-19082-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-25perf probe: Use existing routine to look for a kernel module by dso->short_nameArnaldo Carvalho de Melo1-6/+7
We have map_groups__find_by_name() to look at the list of modules that are in place for a given machine, so use it instead of traversing the machine dso list, which also includes DSOs for userspace. When merging the user and kernel DSO lists a bug was introduced where 'perf probe' stopped being able to add probes to modules using its short name: # perf probe -m usbnet --add usbnet_start_xmit usbnet_start_xmit is out of .text, skip it. Error: Failed to add events. # With this fix it works again: # perf probe -m usbnet --add usbnet_start_xmit Added new event: probe:usbnet_start_xmit (on usbnet_start_xmit in usbnet) You can now use it in all perf tools, such as: perf record -e probe:usbnet_start_xmit -aR sleep 1 # Reported-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> 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> Fixes: 3d39ac538629 ("perf machine: No need to have two DSOs lists") Link: http://lkml.kernel.org/r/20150924015008.GE1897@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-23Merge tag 'perf-core-for-mingo' of ↵Ingo Molnar6-4/+42
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: User visible changes: - Fix a segfault in 'perf probe' when removing uprobe events. (Masami Hiramatsu) - Synthesize COMM event for workloads started from the command line in 'perf record' so that we can have the pid->comm mapping before we get the real PERF_RECORD_COMM switching from perf to the workload. (Namhyung Kim) - Fix build tools/vm/ due to removal of tools/lib/api/fs/debugfs.h. (Arnaldo Carvalho de Melo) Infrastructure changes: - Fix the make tarball targets by including the recently added err.h header in the perf MANIFEST file. (Jiri Olsa) - Don't assume that the event parser returns a non empty evlist. (Wang Nan) - Add way to disambiguate feature detection state files, needed to use tools/build feature detection for multiple components in a single O= output dir, which will be the case with tools/perf/ and tools/lib/bpf/. (Arnaldo Carvalho de Melo) - Fixup FEATURE_{TESTS,DISPLAY} inversion in tools/lib/bpf/. (Arnaldo Carvalho de Melo) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-23Merge branch 'perf/urgent' into perf/core to pick up fixes before pulling ↵Ingo Molnar1-1/+4
new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-23perf record: Synthesize COMM event for a command line workloadNamhyung Kim3-2/+20
When perf creates a new child to profile, the events are enabled on exec(). And in this case, it doesn't synthesize any event for the child since they'll be generated during exec(). But there's an window between the enabling and the event generation. It used to be overcome since samples are only in kernel (so we always have the map) and the comm is overridden by a later COMM event. However it won't work if events are processed and displayed before the COMM event overrides like in 'perf script'. This leads to those early samples (like native_write_msr_safe) not having a comm but pid (like ':15328'). So it needs to synthesize COMM event for the child explicitly before enabling so that it can have a correct comm. But at this time, the comm will be "perf" since it's not exec-ed yet. Committer note: Before this patch: # perf record usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ] # perf script --show-task-events :4429 4429 27909.079372: 1 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. :4429 4429 27909.079375: 1 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. :4429 4429 27909.079376: 10 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. :4429 4429 27909.079377: 223 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. :4429 4429 27909.079378: 6571 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. usleep 4429 27909.079380: PERF_RECORD_COMM exec: usleep:4429/4429 usleep 4429 27909.079381: 185403 cycles: ffffffff810a72d3 flush_signal_handlers (/lib/modules/4. usleep 4429 27909.079444: 2241110 cycles: 7fc575355be3 _dl_start (/usr/lib64/ld-2.20.so) usleep 4429 27909.079875: PERF_RECORD_EXIT(4429:4429):(4429:4429) After: # perf record usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ] # perf script --show-task perf 0 0.000000: PERF_RECORD_COMM: perf:8446/8446 perf 8446 30154.038944: 1 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. perf 8446 30154.038948: 1 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. perf 8446 30154.038949: 9 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. perf 8446 30154.038950: 230 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. perf 8446 30154.038951: 6772 cycles: ffffffff8105f45a native_write_msr_safe (/lib/modules/4. usleep 8446 30154.038952: PERF_RECORD_COMM exec: usleep:8446/8446 usleep 8446 30154.038954: 196923 cycles: ffffffff81766440 _raw_spin_lock (/lib/modules/4.3.0-rc1 usleep 8446 30154.039021: 2292130 cycles: 7f609a173dc4 memcpy (/usr/lib64/ld-2.20.so) usleep 8446 30154.039349: PERF_RECORD_EXIT(8446:8446):(8446:8446) # Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1442881495-2928-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-22perf tools: Add include/err.h into MANIFESTJiri Olsa1-0/+1
Otherwise the tarpkg is incomplete (tarpkg tests fails). 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> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 01ca9fd41d6f ("tools: Add err.h with ERR_PTR PTR_ERR interface") Link: http://lkml.kernel.org/r/1442846143-8556-1-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-22perf tools: Don't assume that the parser returns non empty evsel listWang Nan1-0/+16
Don't blindly retrieve and use a last element in the lists returned by parse_events__scanner(), as it may have collected no entries, i.e. return an empty list. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1441523623-152703-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-22perf probe: Fix a segfault when removing uprobe eventsMasami Hiramatsu1-2/+5
Fix a segfault bug and a small mistake in perf probe -d. Since the "ulist" in perf_del_probe_events is never initialized, strlist__add(ulist, *) always causes a segfault when removing uprobe events by perf probe -d. Also, the "str" local variable is never released if fail to allocate the "klist". This fixes it too. This has been introduced by the commit e607f1426b58 ("perf probe: Print deleted events in cmd_probe()"). Reported-by: Milian Wolff <milian.wolff@kdab.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/20150916125241.4446.44805.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-18perf record: Avoid infinite loop at buildid processing with no samplesMark Rutland1-1/+4
If a session contains no events, we can get stuck in an infinite loop in __perf_session__process_events, with a non-zero file_size and data_offset, but a zero data_size. In this case, we can mmap the entirety of the file (consisting of the file and attribute headers), and fetch_mmaped_event will correctly refuse to read any (unmapped and non-existent) event headers. This causes __perf_session__process_events to unmap the file and retry with the exact same parameters, getting stuck in an infinite loop. This has been observed to result in an exit-time hang when counting rare/unschedulable events with perf record, and can be triggered artificially with the script below: ---- #!/bin/sh printf "REPRO: launching perf\n"; ./perf record -e software/config=9/ sleep 1 & PERF_PID=$!; sleep 0.002; kill -2 $PERF_PID; printf "REPRO: waiting for perf (%d) to exit...\n" "$PERF_PID"; wait $PERF_PID; printf "REPRO: perf exited\n"; ---- To avoid this, have __perf_session__process_events bail out early when the file has no data (i.e. it has no events). Commiter note: I only managed to reproduce this when setting /proc/sys/kernel/kptr_restrict to '1' and changing the code to purposefully not process any samples and no synthesized samples, i.e. kptr_restrict prevents 'record' from synthesizing the kernel mmaps for vmlinux + modules and since it is a workload started from perf, we don't synthesize mmap/comm records for existing threads. Adrian Hunter managed to reproduce it in his environment tho. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org> Tested-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1442423929-12253-1-git-send-email-mark.rutland@arm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-18Merge branch 'perf/urgent' into perf/core, to pick up fixes before applying ↵Ingo Molnar4-9/+31
new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-17perf tools: Bool functions shouldn't return -1Peter Senna Tschudin1-1/+1
Returning a negative value for a boolean function seem to have the undesired effect of returning true. Replace -1 by false in a bool-returning function. The diff of the .s file before and after the change (for x86_64): 3907c3907 < movl $1, %ebx --- > xorl %ebx, %ebx while if -1 is replaced by true, the diff is empty. This issue was found by the following Coccinelle semantic patch: <smpl> @@ identifier f; constant C; typedef bool; @@ bool f (...){ <+... * return -C; ...+> } </smpl> Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Milos Vyletel <milos@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1442484533-19742-1-git-send-email-peter.senna@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-17tools build: Add test for presence of __get_cpuid() gcc builtinArnaldo Carvalho de Melo1-2/+7
The auxtrace code needed by Intel PT uses the __get_cpuid() gcc builtin, that is not present in old systems, breaking the build. Add a test to check for that builtin and disable AUXTRACE in those systems. [acme@rhel5 linux]$ make NO_LIBPERL=1 -C tools/perf O=/tmp/build/perf install-bin make: Entering directory `/home/acme/git/linux/tools/perf' BUILD: Doing 'make -j2' parallel build Auto-detecting system features: <SNIP> ... lzma: [ on ] ... get_cpuid: [ OFF ] <SNIP> config/Makefile:630: Your gcc lacks the __get_cpuid() builtin, disables support for auxtrace/Intel PT, please install a newer gcc MKDIR /tmp/build/perf/util/ <SNIP> This fixes the build on old systems such as RHEL/CentOS 5.11. 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@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Stephane Eranian <eranian@google.com> Cc: Victor Kamensky <victor.kamensky@linaro.org> Cc: Vinson Lee <vlee@twopensource.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-d4puslul0jltoodzpx9r4sje@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-17tools build: Add test for presence of numa_num_possible_cpus() in libnumaArnaldo Carvalho de Melo1-3/+8
The existing numa test checks only if numa.h and numa_available() are present, but that can be satisfied with an old libnuma that is not enough for the 'perf bench numa' entry, so add a test to check for that: [acme@rhel5 linux]$ make NO_AUXTRACE=1 NO_LIBPERL=1 -C tools/perf O=/tmp/build/perf install-bin make: Entering directory `/home/acme/git/linux/tools/perf' BUILD: Doing 'make -j2' parallel build Auto-detecting system features: ... libelf: [ on ] ... libnuma: [ on ] ... numa_num_possible_cpus: [ OFF ] ... libperl: [ on ] <SNIP> config/Makefile:577: Old numa library found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev >= 2.0.8 INSTALL binaries <SNIP> This fixes the build on old systems such as RHEL/CentOS 5.11. 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@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Stephane Eranian <eranian@google.com> Cc: Victor Kamensky <victor.kamensky@linaro.org> Cc: Vinson Lee <vlee@twopensource.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-zqriqkezppi2de2iyjin1tnc@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-17Revert "perf symbols: Fix mismatched declarations for elf_getphdrnum"Arnaldo Carvalho de Melo1-1/+1
This reverts commit f785f2357673d520a0b7b468973cdd197f336494. We have a test to check if elf_getphdrnum() is present, so, if it fails, we'll get: [acme@rhel5 linux]$ cat /tmp/build/perf/feature/test-libelf-getphdrnum.make.output cc1: warnings being treated as errors test-libelf-getphdrnum.c: In function ‘main’: test-libelf-getphdrnum.c:7: warning: implicit declaration of function ‘elf_getphdrnum’ [acme@rhel5 linux]$ And this block will not be compiled: #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT static int elf_getphdrnum(Elf *elf, size_t *dst) ... #endif So, if elf_getphdrnum() is being defined somewhere, there is a problem with the test that is not detecting that function, go fix it. Reported-by: Vinson Lee <vlee@twopensource.com> 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@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Stephane Eranian <eranian@google.com> Cc: Victor Kamensky <victor.kamensky@linaro.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-qn459fal6acvcvm50i8zxx9k@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-17perf stat: Fix per-pkg event reporting bugStephane Eranian1-2/+14
Per-pkg events need to be captured once per processor socket. The code in check_per_pkg() ensures only one value per processor package is used. However there is a problem with this function in case the first CPU of the package does not measure anything for the per-pkg event, but other CPUs do. Consider the following: $ create cgroup FOO; echo $$ >FOO/tasks; taskset -c 1 noploop & $ perf stat -a -I 1000 -e intel_cqm/llc_occupancy/ -G FOO sleep 100 1.00000 <not counted> Bytes intel_cqm/llc_occupancy/ FOO The reason for this is that CPU0 in the cgroup has nothing running on it. Yet check_per_plg() will mark socket0 as processed and no other event value will be considered for the socket. This patch fixes the problem by having check_per_pkg() only consider events which actually ran. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1441286620-10117-1-git-send-email-eranian@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-16Merge branch 'perf/urgent' into perf/core, to resolve a conflictIngo Molnar9-82/+126
Conflicts: tools/perf/ui/browsers/hists.c Signed-off-by: Ingo Molnar <mingo@kernel.org>