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2023-10-17perf pmu: Const-ify file APIsIan Rogers3-12/+13
File APIs don't alter the struct pmu so allow const ones to be passed. Signed-off-by: Ian Rogers <[email protected]> Reviewed-by: Adrian Hunter <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: James Clark <[email protected]> Cc: Suzuki K Poulose <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Will Deacon <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mike Leach <[email protected]> Cc: Jing Zhang <[email protected]> Cc: Kajol Jain <[email protected]> Cc: Thomas Richter <[email protected]> Cc: Kan Liang <[email protected]> Cc: John Garry <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-17perf pmu: Rename perf_pmu__get_default_config to perf_pmu__arch_initIan Rogers2-8/+7
Assign default_config as part of the init. perf_pmu__get_default_config was doing more than just getting the default config and so this is intended to better align with the code. Signed-off-by: Ian Rogers <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: James Clark <[email protected]> Cc: Suzuki K Poulose <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Will Deacon <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mike Leach <[email protected]> Cc: Jing Zhang <[email protected]> Cc: Kajol Jain <[email protected]> Cc: Thomas Richter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Kan Liang <[email protected]> Cc: John Garry <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-17perf intel-pt: Prefer get_unaligned_le64 to memcpy_le64Adrian Hunter1-3/+3
Use get_unaligned_le64() instead of memcpy_le64(..., 8) because it produces simpler code. Signed-off-by: Adrian Hunter <[email protected]> Acked-by: Ian Rogers <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-17perf intel-pt: Use get_unaligned_le16() etcAdrian Hunter1-8/+9
Avoid unaligned access by using get_unaligned_le16(), get_unaligned_le32() and get_unaligned_le64(). Signed-off-by: Adrian Hunter <[email protected]> Acked-by: Ian Rogers <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-17perf intel-pt: Use existing definitions of le16_to_cpu() etcAdrian Hunter1-6/+1
Use definitions from tools/include/linux/kernel.h Signed-off-by: Adrian Hunter <[email protected]> Acked-by: Ian Rogers <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-17perf intel-pt: Simplify intel_pt_get_vmcs()Adrian Hunter1-9/+4
Simplify and remove unnecessary constant expressions. Signed-off-by: Adrian Hunter <[email protected]> Acked-by: Ian Rogers <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf cs-etm: Fix incorrect or missing decoder for raw traceBesar Wicaksono1-41/+65
The decoder creation for raw trace uses metadata from the first CPU. On per-cpu mode, this metadata is incorrectly used for every decoder. On per-process/per-thread traces, the first CPU is CPU0. If CPU0 trace is not enabled, its metadata will be marked unused and the decoder is not created. Perf report dump skips the decoding part because the decoder is missing. To fix this, use metadata of the CPU associated with sample object. Signed-off-by: Besar Wicaksono <[email protected]> Reviewed-by: James Clark <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf bpf_counter: Fix a few memory leaksIan Rogers1-1/+4
Memory leaks were detected by clang-tidy. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf header: Fix various error path memory leaksIan Rogers1-26/+34
Memory leaks were detected by clang-tidy. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf trace-event-info: Avoid passing NULL value to closedirIan Rogers1-1/+2
If opendir failed then closedir was passed NULL which is erroneous. Caught by clang-tidy. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf parse-events: Fix unlikely memory leak when cloning termsIan Rogers1-1/+3
Add missing free on an error path as detected by clang-tidy. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf svghelper: Avoid memory leakIan Rogers1-2/+3
On success path the sib_core and sib_thr values weren't being freed. Detected by clang-tidy. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf dlfilter: Be defensive against potential NULL dereferenceIan Rogers1-1/+3
In the unlikely case of having a symbol without a mapping, avoid a NULL dereference that clang-tidy warns about. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf mem-events: Avoid uninitialized readIan Rogers1-1/+2
pmu should be initialized to NULL before perf_pmus__scan loop. Fix and shrink the scope of pmu at the same time. Issue detected by clang-tidy. Fixes: 5752c20f3787 ("perf mem: Scan all PMUs instead of just core ones") Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf jitdump: Avoid memory leakIan Rogers1-0/+1
jit_repipe_unwinding_info is called in a loop by jit_process_dump, avoid leaking unwinding_data by free-ing before overwriting. Error detected by clang-tidy. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf env: Remove unnecessary NULL testsIan Rogers1-3/+3
clang-tidy was warning: ``` util/env.c:334:23: warning: Access to field 'nr_pmu_mappings' results in a dereference of a null pointer (loaded from variable 'env') [clang-analyzer-core.NullDereference] env->nr_pmu_mappings = pmu_num; ``` As functions are called potentially when !env was true. This condition could never be true as it would produce a segv, so remove the unnecessary NULL tests and silence clang-tidy. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Cc: Ming Wang <[email protected]> Cc: Tom Rix <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf parse-events: Fix for term values that are raw eventsIan Rogers1-5/+3
Raw events can be strings like 'r0xead' but the 0x is optional so they can also be 'read'. On IcelakeX uncore_imc_free_running has an event called 'read' which may be programmed as: ``` $ perf stat -e 'uncore_imc_free_running/event=read/' -a sleep 1 ``` However, the PE_RAW type isn't allowed on the right of a term, even though in this case we just want to interpret it as a string. This leads to the following error on IcelakeX: ``` $ perf stat -e 'uncore_imc_free_running/event=read/' -a sleep 1 event syntax error: '..nning/event=read/' \___ parser error Run 'perf list' for a list of valid events Usage: perf stat [<options>] [<command>] -e, --event <event> event selector. use 'perf list' to list available events ``` Fix this by allowing raw types on the right of terms and treat them as strings, just as is already done for PE_LEGACY_CACHE. Make this consistent by just entirely removing name_or_legacy and always using name_or_raw that covers all three cases. Fixes: 6fd1e5191591 ("perf parse-events: Support PMUs for legacy cache events") Signed-off-by: Ian Rogers <[email protected]> Cc: James Clark <[email protected]> Cc: Kan Liang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf symbols: Add 'intel_idle_ibrs' to the list of idle symbolsArnaldo Carvalho de Melo1-0/+1
This is a longstanding to do list entry: we need a way to see that a sample took place while in idle state, as the current way to do it is to infer that by the name of the functions that in such state have more samples, IOW: a hack. Maybe we can do flip a bit in samples that take place inside the enter/exit idle section in do_idle()? But till then, add one more :-\ Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Frederic Weisbecker <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-12perf parse-events: Avoid erange from hex numbersIan Rogers1-2/+2
We specify that a "num_hex" comprises 1 or more digits, however, that allows strtoull to fail with ERANGE. Limit the number of hex digits to being between 1 and 16. Before: ``` $ perf stat -e 'cpu/rE7574c47490475745/' true perf: util/parse-events.c:215: fix_raw: Assertion `errno == 0' failed. Aborted (core dumped) ``` After: ``` $ perf stat -e 'cpu/rE7574c47490475745/' true event syntax error: 'cpu/rE7574c47490475745/' \___ Bad event or PMU Unable to find PMU or event on a PMU of 'cpu' Initial error: event syntax error: 'cpu/rE7574c47490475745/' \___ unknown term 'rE7574c47490475745' for pmu 'cpu' valid terms: event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,config3,name,period,percore,metric-id Run 'perf list' for a list of valid events Usage: perf stat [<options>] [<command>] -e, --event <event> event selector. use 'perf list' to list available events ``` Issue found through fuzz testing. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-10Merge tag 'perf-tools-fixes-for-v6.6-1-2023-09-25' into perf-tools-nextArnaldo Carvalho de Melo4-519/+3
To pick up the 'perf bench sched-seccomp-notify' changes to allow us to continue build testing perf-tools-next with the set of distro containers, where some older ones don't have a recent enough seccomp.h UAPI header that contains defines needed by this new 'perf bench' workload. Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-10-04tools/perf: Add "is_kmod" to struct dso to check if it is kernel moduleAthira Rajeev2-0/+3
Update "struct dso" to include new member "is_kmod". This new field will determine if the file is a kernel module or not. To resolve the address from a sample, perf looks at the DSO maps. In case of address from a kernel module, there were some address found to be not resolved. This was observed while running perf test for "Object code reading". Though the ip falls beteen the start address of the loaded module (perf map->start ) and end address ( perf map->end), it was unresolved. This was happening because in some cases for kernel modules, address from sample points to stub instructions. To identify if the DSO is a kernel module, the new field "is_kmod" is added to "struct dso". Reported-by: Disha Goel <[email protected]> Signed-off-by: Athira Rajeev <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-04tools/perf: Add text_end to "struct dso" to save .text section sizeAthira Rajeev3-1/+6
Update "struct dso" to include new member "text_end". This new field will represent the offset for end of text section for a dso. For elf, this value is derived as: sh_size (Size of section in byes) + sh_offset (Section file offst) of the elf header for text. For bfd, this value is derived as: 1. For PE file, section->size + ( section->vma - dso->text_offset) 2. Other cases: section->filepos (file position) + section->size (size of section) To resolve the address from a sample, perf looks at the DSO maps. In case of address from a kernel module, there were some address found to be not resolved. This was observed while running perf test for "Object code reading". Though the ip falls beteen the start address of the loaded module (perf map->start ) and end address ( perf map->end), it was unresolved. Example: Reading object code for memory address: 0xc008000007f0142c File is: /lib/modules/6.5.0-rc3+/kernel/fs/xfs/xfs.ko On file address is: 0x1114cc Objdump command is: objdump -z -d --start-address=0x11142c --stop-address=0x1114ac /lib/modules/6.5.0-rc3+/kernel/fs/xfs/xfs.ko objdump read too few bytes: 128 test child finished with -1 Here, module is loaded at: # cat /proc/modules | grep xfs xfs 2228224 3 - Live 0xc008000007d00000 From objdump for xfs module, text section is: text 0010f7bc 0000000000000000 0000000000000000 000000a0 2**4 Here the offset for 0xc008000007f0142c ie 0x112074 falls out .text section which is up to 0x10f7bc. In this case for module, the address 0xc008000007e11fd4 is pointing to stub instructions. This address range represents the module stubs which is allocated on module load and hence is not part of DSO offset. To identify such address, which falls out of text section and within module end, added the new field "text_end" to "struct dso". Reported-by: Disha Goel <[email protected]> Signed-off-by: Athira Rajeev <[email protected]> Reviewed-by: Adrian Hunter <[email protected]> Reviewed-by: Kajol Jain <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-10-04perf hisi-ptt: Fix memory leak in lseek failure handlingKuan-Wei Chiu1-1/+3
In the previous code, there was a memory leak issue where the previously allocated memory was not freed upon a failed lseek operation. This patch addresses the problem by releasing the old memory before returning -errno in case of a lseek failure. This ensures that memory is properly managed and avoids potential memory leaks. Signed-off-by: Kuan-Wei Chiu <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-29perf intel-pt: Fix async branch flagsAdrian Hunter1-0/+2
Ensure PERF_IP_FLAG_ASYNC is set always for asynchronous branches (i.e. interrupts etc). Fixes: 90e457f7be08 ("perf tools: Add Intel PT support") Cc: [email protected] Signed-off-by: Adrian Hunter <[email protected]> Acked-by: Namhyung Kim <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-29perf dlfilter: Fix use of addr_location__exit() in dlfilter__object_code()Adrian Hunter1-17/+15
Stop calling addr_location__exit() when addr_location__init() was not called. Fixes: 0dd5041c9a0e ("perf addr_location: Add init/exit/copy functions") Cc: [email protected] Signed-off-by: Adrian Hunter <[email protected]> Acked-by: Namhyung Kim <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-29perf pmus: Make PMU alias name loading lazyIan Rogers3-20/+31
PMU alias names were computed when the first perf_pmu is created, scanning all PMUs in event sources for a file called alias that generally doesn't exist. Switch to trying to load the file when all PMU related files are loaded in lookup. This would cause a PMU name lookup of an alias name to fail if no PMUs were loaded, so in that case all PMUs are loaded and the find repeated. The overhead is similar but in the (very) general case not all PMUs are scanned for the alias file. As the overhead occurs once per invocation it doesn't show in perf bench internals pmu-scan. On a tigerlake machine, the number of openat system calls for an event of cpu/cycles/ with perf stat reduces from 94 to 69 (ie 25 fewer openat calls). Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: James Clark <[email protected]> Cc: Leo Yan <[email protected]> Cc: Kan Liang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-27perf metric: "Compat" supports regular expression matching identifiersJing Zhang1-1/+1
The jevent "Compat" is used for uncore PMU alias or metric definitions. The same PMU driver has different PMU identifiers due to different hardware versions and types, but they may have some common PMU metric. Since a Compat value can only match one identifier, when adding the same metric to PMUs with different identifiers, each identifier needs to be defined once, which is not streamlined enough. So let "Compat" support using regular expression to match multiple identifiers for uncore PMU metric. Signed-off-by: Jing Zhang <[email protected]> Reviewed-by: John Garry <[email protected]> Reviewed-by: Ian Rogers <[email protected]> Tested-by: Ian Rogers <[email protected]> Cc: James Clark <[email protected]> Cc: Will Deacon <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mike Leach <[email protected]> Cc: Shuai Xue <[email protected]> Cc: Zhuo Song <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-27perf pmu: "Compat" supports regular expression matching identifiersJing Zhang2-2/+26
The jevent "Compat" is used for uncore PMU alias or metric definitions. The same PMU driver has different PMU identifiers due to different hardware versions and types, but they may have some common PMU event. Since a Compat value can only match one identifier, when adding the same event alias to PMUs with different identifiers, each identifier needs to be defined once, which is not streamlined enough. So let "Compat" support using regular expression to match identifiers for uncore PMU alias. For example, if the "Compat" value is set to "43401|43c01", it would be able to match PMU identifiers such as "43401" or "43c01", which correspond to CMN600_r0p0 or CMN700_r0p0. Signed-off-by: Jing Zhang <[email protected]> Reviewed-by: Ian Rogers <[email protected]> Tested-by: Ian Rogers <[email protected]> Cc: James Clark <[email protected]> Cc: Will Deacon <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mike Leach <[email protected]> Cc: Shuai Xue <[email protected]> Cc: Zhuo Song <[email protected]> Cc: John Garry <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-27perf record: Fix BTF type checks in the off-cpu profilingNamhyung Kim1-2/+3
The BTF func proto for a tracepoint has one more argument than the actual tracepoint function since it has a context argument at the begining. So it should compare to 5 when the tracepoint has 4 arguments. typedef void (*btf_trace_sched_switch)(void *, bool, struct task_struct *, struct task_struct *, unsigned int); Also, recent change in the perf tool would use a hand-written minimal vmlinux.h to generate BTF in the skeleton. So it won't have the info of the tracepoint. Anyway it should use the kernel's vmlinux BTF to check the type in the kernel. Fixes: b36888f71c85 ("perf record: Handle argument change in sched_switch") Reviewed-by: Ian Rogers <[email protected]> Acked-by: Song Liu <[email protected]> Cc: Hao Luo <[email protected]> CC: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-26perf evlist: Avoid frequency mode for the dummy eventIan Rogers1-2/+3
Dummy events are created with an attribute where the period and freq are zero. evsel__config will then see the uninitialized values and initialize them in evsel__default_freq_period. As fequency mode is used by default the dummy event would be set to use frequency mode. However, this has no effect on the dummy event but does cause unnecessary timers/interrupts. Avoid this overhead by setting the period to 1 for dummy events. evlist__add_aux_dummy calls evlist__add_dummy then sets freq=0 and period=1. This isn't necessary after this change and so the setting is removed. From Stephane: The dummy event is not counting anything. It is used to collect mmap records and avoid a race condition during the synthesize mmap phase of perf record. As such, it should not cause any overhead during active profiling. Yet, it did. Because of a bug the dummy event was programmed as a sampling event in frequency mode. Events in that mode incur more kernel overheads because on timer tick, the kernel has to look at the number of samples for each event and potentially adjust the sampling period to achieve the desired frequency. The dummy event was therefore adding a frequency event to task and ctx contexts we may otherwise not have any, e.g., perf record -a -e cpu/event=0x3c,period=10000000/. On each timer tick the perf_adjust_freq_unthr_context() is invoked and if ctx->nr_freq is non-zero, then the kernel will loop over ALL the events of the context looking for frequency mode ones. In doing, so it locks the context, and enable/disable the PMU of each hw event. If all the events of the context are in period mode, the kernel will have to traverse the list for nothing incurring overhead. The overhead is multiplied by a very large factor when this happens in a guest kernel. There is no need for the dummy event to be in frequency mode, it does not count anything and therefore should not cause extra overhead for no reason. Fixes: 5bae0250237f ("perf evlist: Introduce perf_evlist__new_dummy constructor") Reported-by: Stephane Eranian <[email protected]> Signed-off-by: Ian Rogers <[email protected]> Acked-by: Adrian Hunter <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Kan Liang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-26perf pmu: Fix perf stat output with correct scale and unitWyes Karny1-4/+4
The perf_pmu__parse_* functions for the sysfs files of pmu event’s scale, unit, per-pkg and snapshot were updated in commit 7b723dbb96e8 ("perf pmu: Be lazy about loading event info files from sysfs"). However, the paths for these sysfs files were incorrect. This resulted in perf stat reporting values with wrong scaling and missing units. This is fixed by correcting the paths for these sysfs files. Before this fix: $sudo perf stat -e power/energy-pkg/ -- sleep 2 Performance counter stats for 'system wide': 351,217,188,864 power/energy-pkg/ 2.004127961 seconds time elapsed After this fix: $sudo perf stat -e power/energy-pkg/ -- sleep 2 Performance counter stats for 'system wide': 80.58 Joules power/energy-pkg/ 2.004009749 seconds time elapsed Fixes: 7b723dbb96e8 ("perf pmu: Be lazy about loading event info files from sysfs") Signed-off-by: Wyes Karny <[email protected]> Reviewed-by: Ian Rogers <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-18perf parse-events: Fix tracepoint name memory leakIan Rogers1-0/+1
Fuzzing found that an invalid tracepoint name would create a memory leak with an address sanitizer build: ``` $ perf stat -e '*:o/' true event syntax error: '*:o/' \___ parser error Run 'perf list' for a list of valid events Usage: perf stat [<options>] [<command>] -e, --event <event> event selector. use 'perf list' to list available events ================================================================= ==59380==ERROR: LeakSanitizer: detected memory leaks Direct leak of 4 byte(s) in 2 object(s) allocated from: #0 0x7f38ac07077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439 #1 0x55f2f41be73b in str util/parse-events.l:49 #2 0x55f2f41d08e8 in parse_events_lex util/parse-events.l:338 #3 0x55f2f41dc3b1 in parse_events_parse util/parse-events-bison.c:1464 #4 0x55f2f410b8b3 in parse_events__scanner util/parse-events.c:1822 #5 0x55f2f410d1b9 in __parse_events util/parse-events.c:2094 #6 0x55f2f410e57f in parse_events_option util/parse-events.c:2279 #7 0x55f2f4427b56 in get_value tools/lib/subcmd/parse-options.c:251 #8 0x55f2f4428d98 in parse_short_opt tools/lib/subcmd/parse-options.c:351 #9 0x55f2f4429d80 in parse_options_step tools/lib/subcmd/parse-options.c:539 #10 0x55f2f442acb9 in parse_options_subcommand tools/lib/subcmd/parse-options.c:654 #11 0x55f2f3ec99fc in cmd_stat tools/perf/builtin-stat.c:2501 #12 0x55f2f4093289 in run_builtin tools/perf/perf.c:322 #13 0x55f2f40937f5 in handle_internal_command tools/perf/perf.c:375 #14 0x55f2f4093bbd in run_argv tools/perf/perf.c:419 #15 0x55f2f409412b in main tools/perf/perf.c:535 SUMMARY: AddressSanitizer: 4 byte(s) leaked in 2 allocation(s). ``` Fix by adding the missing destructor. Fixes: 865582c3f48e ("perf tools: Adds the tracepoint name parsing support") Signed-off-by: Ian Rogers <[email protected]> Cc: He Kuang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-18perf kwork top: Simplify bool conversionYang Li1-1/+1
./tools/perf/util/bpf_kwork_top.c:120:53-58: WARNING: conversion to bool not needed here Signed-off-by: Yang Li <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-17perf pmu: Ensure all alias variables are initializedIan Rogers1-1/+1
Fix an error detected by memory sanitizer: ``` ==4033==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x55fb0fbedfc7 in read_alias_info tools/perf/util/pmu.c:457:6 #1 0x55fb0fbea339 in check_info_data tools/perf/util/pmu.c:1434:2 #2 0x55fb0fbea339 in perf_pmu__check_alias tools/perf/util/pmu.c:1504:9 #3 0x55fb0fbdca85 in parse_events_add_pmu tools/perf/util/parse-events.c:1429:32 #4 0x55fb0f965230 in parse_events_parse tools/perf/util/parse-events.y:299:6 #5 0x55fb0fbdf6b2 in parse_events__scanner tools/perf/util/parse-events.c:1822:8 #6 0x55fb0fbdf8c1 in __parse_events tools/perf/util/parse-events.c:2094:8 #7 0x55fb0fa8ffa9 in parse_events tools/perf/util/parse-events.h:41:9 #8 0x55fb0fa8ffa9 in test_event tools/perf/tests/parse-events.c:2393:8 #9 0x55fb0fa8f458 in test__pmu_events tools/perf/tests/parse-events.c:2551:15 #10 0x55fb0fa6d93f in run_test tools/perf/tests/builtin-test.c:242:9 #11 0x55fb0fa6d93f in test_and_print tools/perf/tests/builtin-test.c:271:8 #12 0x55fb0fa6d082 in __cmd_test tools/perf/tests/builtin-test.c:442:5 #13 0x55fb0fa6d082 in cmd_test tools/perf/tests/builtin-test.c:564:9 #14 0x55fb0f942720 in run_builtin tools/perf/perf.c:322:11 #15 0x55fb0f942486 in handle_internal_command tools/perf/perf.c:375:8 #16 0x55fb0f941dab in run_argv tools/perf/perf.c:419:2 #17 0x55fb0f941dab in main tools/perf/perf.c:535:3 ``` Fixes: 7b723dbb96e8 ("perf pmu: Be lazy about loading event info files from sysfs") Signed-off-by: Ian Rogers <[email protected]> Cc: James Clark <[email protected]> Cc: Kan Liang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-17perf trace: Avoid compile error wrt redefining boolIan Rogers1-0/+2
Make part of an existing TODO conditional to avoid the following build error: ``` tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c:26:14: error: cannot combine with previous 'char' declaration specifier 26 | typedef char bool; | ^ include/stdbool.h:20:14: note: expanded from macro 'bool' 20 | #define bool _Bool | ^ tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c:26:1: error: typedef requires a name [-Werror,-Wmissing-declarations] 26 | typedef char bool; | ^~~~~~~~~~~~~~~~~ 2 errors generated. ``` Signed-off-by: Ian Rogers <[email protected]> Cc: Leo Yan <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-17perf bpf-prologue: Remove unused fileIan Rogers1-508/+0
Commit 3d6dfae88917 ("perf parse-events: Remove BPF event support") removed building bpf-prologue.c but failed to remove the actual file. Fixes: 3d6dfae88917 ("perf parse-events: Remove BPF event support") Signed-off-by: Ian Rogers <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-15perf pmu: Remove unused functionJames Clark2-6/+0
pmu_events_table__find() is no longer used so remove it and its Arm specific version. Signed-off-by: James Clark <[email protected]> Reviewed-by: Ian Rogers <[email protected]> Reviewed-by: John Garry <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Eduard Zingerman <[email protected]> Cc: Will Deacon <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mike Leach <[email protected]> Cc: Jing Zhang <[email protected]> Cc: Haixin Yu <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-15perf pmus: Simplify perf_pmus__find_core_pmu()James Clark1-13/+1
Currently the while loop always either exits on the first iteration with a core PMU, or exits with NULL on heterogeneous systems or when not all CPUs are online. Both of the latter behaviors are undesirable for platforms other than Arm so simplify it to always return the first core PMU, or NULL if none exist. This behavior was depended on by the Arm version of pmu_metrics_table__find(), so the logic has been moved there instead. Signed-off-by: James Clark <[email protected]> Suggested-by: Ian Rogers <[email protected]> Reviewed-by: Ian Rogers <[email protected]> Reviewed-by: John Garry <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Eduard Zingerman <[email protected]> Cc: Will Deacon <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mike Leach <[email protected]> Cc: Jing Zhang <[email protected]> Cc: Haixin Yu <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-15perf pmu: Move pmu__find_core_pmu() to pmus.cJames Clark4-20/+21
pmu__find_core_pmu() more logically belongs in pmus.c because it iterates over all PMUs, so move it to pmus.c At the same time rename it to perf_pmus__find_core_pmu() to match the naming convention in this file. list_prepare_entry() can't be used in perf_pmus__scan_core() anymore now that it's called from the same compilation unit. This is with -O2 (specifically -O1 -ftree-vrp -finline-functions -finline-small-functions) which allow the bounds of the array access to be determined at compile time. list_prepare_entry() subtracts the offset of the 'list' member in struct perf_pmu from &core_pmus, which isn't a struct perf_pmu. The compiler sees that pmu results in &core_pmus - 8 and refuses to compile. At runtime this works because list_for_each_entry_continue() always adds the offset back again before dereferencing ->next, but it's technically undefined behavior. With -fsanitize=undefined an additional warning is generated. Using list_first_entry_or_null() to get the first entry here avoids doing &core_pmus - 8 but has the same result and fixes both the compile warning and the undefined behavior warning. There are other uses of list_prepare_entry() in pmus.c, but the compiler doesn't seem to be able to see that they can also be called with &core_pmus, so I won't change any at this time. Signed-off-by: James Clark <[email protected]> Reviewed-by: Ian Rogers <[email protected]> Reviewed-by: John Garry <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Eduard Zingerman <[email protected]> Cc: Will Deacon <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mike Leach <[email protected]> Cc: Jing Zhang <[email protected]> Cc: Haixin Yu <[email protected]> Cc: Kan Liang <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-15perf symbol: Avoid an undefined behavior warningIan Rogers1-2/+1
The node (nd) may be NULL and pointer arithmetic on NULL is undefined behavior. Move the computation of next below the NULL check on the node. Signed-off-by: Ian Rogers <[email protected]> Cc: James Clark <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>
2023-09-12perf bpf-filter: Add YYDEBUGIan Rogers1-0/+4
YYDEBUG enables line numbers and other error helpers in the generated bpf-filter-bison.c. Conditionally enabled only for debug builds. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Gaosheng Cui <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rob Herring <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf pmu: Add YYDEBUGIan Rogers1-0/+4
YYDEBUG enables line numbers and other error helpers in the generated pmu-bison.c. Conditionally enabled only for debug builds. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Gaosheng Cui <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rob Herring <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf expr: Make YYDEBUG dependent on doing a debug buildIan Rogers1-0/+2
YYDEBUG enables line numbers and other error helpers in the generated expr-bison.c. These shouldn't be generated when debugging isn't enabled. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Gaosheng Cui <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rob Herring <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf parse-events: Make YYDEBUG dependent on doing a debug buildIan Rogers1-0/+2
YYDEBUG enables line numbers and other error helpers in the generated parse-events-bison.c. These shouldn't be generated when debugging isn't enabled. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Gaosheng Cui <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rob Herring <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf parse-events: Remove unused header filesIan Rogers1-3/+0
The fnmatch header is now used in the PMU matching logic in pmu.c. Signed-off-by: Ian Rogers <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Gaosheng Cui <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rob Herring <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf util: Add a function for replacing characters in a stringJames Clark2-0/+49
It finds all occurrences of a single character and replaces them with a multi character string. This will be used in a test in a following commit. Reviewed-by: Ian Rogers <[email protected]> Signed-off-by: James Clark <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Chen Zhongjin <[email protected]> Cc: Eduard Zingerman <[email protected]> Cc: Haixin Yu <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jing Zhang <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: John Garry <[email protected]> Cc: Kajol Jain <[email protected]> Cc: Kan Liang <[email protected]> Cc: Leo Yan <[email protected]> Cc: Liam Howlett <[email protected]> Cc: Madhavan Srinivasan <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Mike Leach <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yang Jihong <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf list pfm: Retry supported test with exclude_kernelIan Rogers1-1/+14
With paranoia set at 2 evsel__open will fail with EACCES for non-root users. To avoid this stopping libpfm4 events from being printed, retry with exclude_kernel enabled - copying the regular is_event_supported test. Signed-off-by: Ian Rogers <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Kang Minchul <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Richter <[email protected]> Cc: Xing Zhengjun <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf list: Avoid a hardcoded cpu PMU nameIan Rogers1-11/+17
Use the first core PMU instead. On a Raspberry Pi, before: $ perf list ... cpu/t1=v1[,t2=v2,t3 ...]/modifier [Raw hardware event descriptor] [(see 'man perf-list' on how to encode it)] ... After: $ perf list ... armv8_cortex_a72/t1=v1[,t2=v2,t3 ...]/modifier [Raw hardware event descriptor] [(see 'man perf-list' on how to encode it)] ... ``` Signed-off-by: Ian Rogers <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Kang Minchul <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Richter <[email protected]> Cc: Xing Zhengjun <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf lock contention: Add -G/--cgroup-filter optionNamhyung Kim5-2/+35
The -G/--cgroup-filter is to limit lock contention collection on the tasks in the specific cgroups only. $ sudo ./perf lock con -abt -G /user.slice/.../vte-spawn-52221fb8-b33f-4a52-b5c3-e35d1e6fc0e0.scope \ ./perf bench sched messaging # Running 'sched/messaging' benchmark: # 20 sender and receiver processes per group # 10 groups == 400 processes run Total time: 0.174 [sec] contended total wait max wait avg wait pid comm 4 114.45 us 60.06 us 28.61 us 214847 sched-messaging 2 111.40 us 60.84 us 55.70 us 214848 sched-messaging 2 106.09 us 59.42 us 53.04 us 214837 sched-messaging 1 81.70 us 81.70 us 81.70 us 214709 sched-messaging 68 78.44 us 6.83 us 1.15 us 214633 sched-messaging 69 73.71 us 2.69 us 1.07 us 214632 sched-messaging 4 72.62 us 60.83 us 18.15 us 214850 sched-messaging 2 71.75 us 67.60 us 35.88 us 214840 sched-messaging 2 69.29 us 67.53 us 34.65 us 214804 sched-messaging 2 69.00 us 68.23 us 34.50 us 214826 sched-messaging ... Export cgroup__new() function as it's needed from outside. Reviewed-by: Ian Rogers <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Hao Luo <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Song Liu <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2023-09-12perf lock contention: Add --lock-cgroup optionNamhyung Kim4-9/+42
The --lock-cgroup option shows lock contention stats break down by cgroups. Add LOCK_AGGR_CGROUP mode and use it instead of use_cgroup field. $ sudo ./perf lock con -ab --lock-cgroup sleep 1 contended total wait max wait avg wait cgroup 8 15.70 us 6.34 us 1.96 us / 2 1.48 us 747 ns 738 ns /user.slice/.../app.slice/app-gnome-google\x2dchrome-6442.scope 1 848 ns 848 ns 848 ns /user.slice/.../session.slice/[email protected] 1 220 ns 220 ns 220 ns /user.slice/.../session.slice/pipewire-pulse.service For now, the cgroup mode only works with BPF (-b). Committer notes: Remove -g as it is used in the other tools with a clear meaning of collect/show callchains. As agreed with Namhyung off list. Reviewed-by: Ian Rogers <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Hao Luo <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Song Liu <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>