kernel/linux.git/tools/perf/util/session.c, branch v6.12.80

perf session: Fix handling when buffer exceeds 2 GiB

2025-10-19T14:33:37+00:00

[ Upstream commit c17dda8013495d8132c976cbf349be9949d0fbd1 ] If a user specifies an AUX buffer larger than 2 GiB, the returned size may exceed 0x80000000. Since the err variable is defined as a signed 32-bit integer, such a value overflows and becomes negative. As a result, the perf record command reports an error: 0x146e8 [0x30]: failed to process type: 71 [Unknown error 183711232] Change the type of the err variable to a signed 64-bit integer to accommodate large buffer sizes correctly. Fixes: d5652d865ea734a1 ("perf session: Add ability to skip 4GiB or more") Reported-by: Tamas Zsoldos Signed-off-by: Leo Yan Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Link: https://lore.kernel.org/r/20250808-perf_fix_big_buffer_size-v1-1-45f45444a9a4@arm.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf env: Find correct branch counter info on hybrid

2024-09-11T16:08:46+00:00

No event is printed in the "Branch Counter" column on hybrid machines. For example, $ perf record -e "{cpu_core/branch-instructions/pp,cpu_core/branches/}:S" -j any,counter $ perf report --total-cycles # Branch counter abbr list: # cpu_core/branch-instructions/pp = A # cpu_core/branches/ = B # '-' No event occurs # '+' Event occurrences may be lost due to branch counter saturated # # Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter # ............... .............. ........... .......... .............. 44.54% 727.1K 0.00% 1 |+ |+ | 36.31% 592.7K 0.00% 2 |+ |+ | 17.83% 291.1K 0.00% 1 |+ |+ | The branch counter information (br_cntr_width and br_cntr_nr) in the perf_env is retrieved from the CPU_PMU_CAPS. However, the CPU_PMU_CAPS is not available on hybrid machines. Without the width information, the number of occurrences of an event cannot be calculated. For a hybrid machine, the caps information should be retrieved from the PMU_CAPS, and stored in the perf_env->pmu_caps. Add a perf_env__find_br_cntr_info() to return the correct branch counter information from the corresponding fields. Committer notes: While testing I couldn't s ee those "Branch counter" columns enabled by pressing 'B' on the TUI, after reporting it to the list Kan explained the situation: For a hybrid client, the "Branch Counter" feature is only supported starting from the just released Lunar Lake. Perf falls back to only "ANY" on your Raptor Lake. The "The branch counter is not available" message is expected. Here is the 'perf evlist' result from my Lunar Lake machine, # perf evlist -v cpu_core/branch-instructions/pp: type: 4 (cpu_core), size: 136, config: 0xc4 (branch-instructions), { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|READ|PERIOD|BRANCH_STACK|IDENTIFIER, read_format: ID|GROUP|LOST, disabled: 1, freq: 1, enable_on_exec: 1, precise_ip: 2, sample_id_all: 1, exclude_guest: 1, branch_sample_type: ANY|COUNTERS # Fixes: 6f9d8d1de2c61288 ("perf script: Add branch counters") Reviewed-by: Ian Rogers Signed-off-by: Kan Liang Cc: Adrian Hunter Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Link: https://lore.kernel.org/r/20240909184201.553519-1-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf header: Remove repipe option

2024-08-30T12:24:27+00:00

No longer used by `perf inject` the repipe_fd is always -1 and repipe is always false. Remove the options and associated code knowing the constant values of the removed variables. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Nick Terrell Cc: Peter Zijlstra Cc: Yanteng Si Cc: Yicong Yang Link: https://lore.kernel.org/r/20240829150154.37929-8-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf inject: Overhaul handling of pipe files

2024-08-30T12:23:51+00:00

Previously inject->is_pipe was set if the input or output were a pipe. Determining the input was a pipe had to be done prior to starting the session and opening the file. This was done by comparing the input file name with '-' but it fails if the pipe file is written to disk. Opening a pipe file from disk will correctly set perf_data.is_pipe, but this is too late for 'perf inject' and results in a broken file. A workaround is 'cat pipe_perf|perf inject -i - ...'. This change removes inject->is_pipe and changes the dependent conditions to use the is_pipe flag on the input (inject->session->data) and output files (inject->output). This ensures the is_pipe condition reflects things like the header being read. The change removes the use of perf file header repiping, that is writing the file header out while reading it in. The case of input pipe and output file cannot repipe as the attributes for the file are unknown. To resolve this, write the file header when writing to disk and as the attributes may be unknown, write them after the data. Update sessions repipe variable to be trace_event_repipe as those are the only events now impacted by it. Update __perf_session__new as the repipe_fd no longer needs passing. Fully removing repipe from session header reading will be done in a later change. Committer testing: root@number:~# perf record -e syscalls:sys_enter_*sleep/max-stack=4/ -o - sleep 0.01 | perf report -i - # To display the perf.data header info, please use --header/--header-only options. # [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.050 MB - ] # # Total Lost Samples: 0 # # Samples: 1 of event 'syscalls:sys_enter_clock_nanosleep' # Event count (approx.): 1 # # Overhead Command Shared Object Symbol # ........ ....... ............. ............................... # 100.00% sleep libc.so.6 [.] clock_nanosleep@GLIBC_2.2.5 | ---__libc_start_main@@GLIBC_2.34 __libc_start_call_main 0x562fc2560a9f clock_nanosleep@GLIBC_2.2.5 # # (Tip: Create an archive with symtabs to analyse on other machine: perf archive) # root@number:~# perf record -e syscalls:sys_enter_*sleep/max-stack=4/ -o - sleep 0.01 > pipe.data [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.050 MB - ] root@number:~# perf report --stdio -i pipe.data # To display the perf.data header info, please use --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 1 of event 'syscalls:sys_enter_clock_nanosleep' # Event count (approx.): 1 # # Overhead Command Shared Object Symbol # ........ ....... ............. ............................... # 100.00% sleep libc.so.6 [.] clock_nanosleep@GLIBC_2.2.5 | ---__libc_start_main@@GLIBC_2.34 __libc_start_call_main 0x55f775975a9f clock_nanosleep@GLIBC_2.2.5 # # (Tip: To set sampling period of individual events use perf record -e cpu/cpu-cycles,period=100001/,cpu/branches,period=10001/ ...) # root@number:~# Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Nick Terrell Cc: Peter Zijlstra Cc: Yanteng Si Cc: Yicong Yang Link: https://lore.kernel.org/r/20240829150154.37929-7-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Print lost samples due to BPF filter

2024-08-28T21:07:20+00:00

Print the actual dropped sample count in the event stat. $ sudo perf record -o- -e cycles --filter 'period < 10000' \ -e instructions --filter 'ip > 0x8000000000000000' perf test -w noploop | \ perf report --stat -i- [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.058 MB - ] Aggregated stats: TOTAL events: 469 MMAP events: 268 (57.1%) COMM events: 2 ( 0.4%) EXIT events: 1 ( 0.2%) SAMPLE events: 16 ( 3.4%) MMAP2 events: 22 ( 4.7%) LOST_SAMPLES events: 2 ( 0.4%) KSYMBOL events: 89 (19.0%) BPF_EVENT events: 39 ( 8.3%) ATTR events: 2 ( 0.4%) FINISHED_ROUND events: 1 ( 0.2%) ID_INDEX events: 1 ( 0.2%) THREAD_MAP events: 1 ( 0.2%) CPU_MAP events: 1 ( 0.2%) EVENT_UPDATE events: 2 ( 0.4%) TIME_CONV events: 1 ( 0.2%) FEATURE events: 20 ( 4.3%) FINISHED_INIT events: 1 ( 0.2%) cycles stats: SAMPLE events: 2 LOST_SAMPLES (BPF) events: 4010 instructions stats: SAMPLE events: 14 LOST_SAMPLES (BPF) events: 3990 Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: KP Singh Cc: Kan Liang Cc: Peter Zijlstra Cc: Song Liu Link: https://lore.kernel.org/r/20240820154504.128923-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf session: Constify tool

2024-08-12T21:14:17+00:00

Make tool const now that all uses are const and perf_tool__fill_defaults() won't be used. The aim is to better capture that sessions don't mutate tools. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Anshuman Khandual Cc: Athira Rajeev Cc: Huacai Chen Cc: Ilkka Koskinen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Jonathan Cameron Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Nick Desaulniers Cc: Nick Terrell Cc: Oliver Upton Cc: Peter Zijlstra Cc: Song Liu Cc: Sun Haiyong Cc: Suzuki Poulouse Cc: Will Deacon Cc: Yanteng Si Cc: Yicong Yang Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20240812204720.631678-28-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tool: Remove perf_tool__fill_defaults()

2024-08-12T21:13:58+00:00

Now all tools are fully initialized prior to use it has no use so remove. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Anshuman Khandual Cc: Athira Rajeev Cc: Huacai Chen Cc: Ilkka Koskinen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Jonathan Cameron Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Nick Desaulniers Cc: Nick Terrell Cc: Oliver Upton Cc: Peter Zijlstra Cc: Song Liu Cc: Sun Haiyong Cc: Suzuki Poulouse Cc: Will Deacon Cc: Yanteng Si Cc: Yicong Yang Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20240812204720.631678-27-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tool: Move fill defaults into tool.c

2024-08-12T21:05:39+00:00

The aim here is to eventually make perf_tool__fill_defaults() an init function so that the tools struct is more const. Create a tool.c to go along with tool.h. Move perf_tool__fill_defaults() out of session.c into tool.c along with the default stub values. Add perf_tool__compressed_is_stub() for a test in perf_session__process_user_event(). perf_session__process_compressed_event() is only used from being default initialized so migrate into tool.c. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Anshuman Khandual Cc: Athira Rajeev Cc: Huacai Chen Cc: Ilkka Koskinen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Jonathan Cameron Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Nick Desaulniers Cc: Nick Terrell Cc: Oliver Upton Cc: Peter Zijlstra Cc: Song Liu Cc: Sun Haiyong Cc: Suzuki Poulouse Cc: Will Deacon Cc: Yanteng Si Cc: Yicong Yang Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20240812204720.631678-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tool: Constify tool pointers

2024-08-12T21:05:14+00:00

The tool pointer (to a struct largely of function pointers) is passed around but is unchanged except at initialization. Change parameter and variable types to be const to lower the possibilities of what could happen with a tool. Reviewed-by: Adrian Hunter Signed-off-by: Ian Rogers Tested-by: Adrian Hunter Tested-by: Leo Yan Cc: Alexander Shishkin Cc: Anshuman Khandual Cc: Athira Rajeev Cc: Huacai Chen Cc: Ilkka Koskinen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Jonathan Cameron Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Nick Desaulniers Cc: Nick Terrell Cc: Oliver Upton Cc: Peter Zijlstra Cc: Song Liu Cc: Sun Haiyong Cc: Suzuki Poulouse Cc: Will Deacon Cc: Yanteng Si Cc: Yicong Yang Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20240812204720.631678-4-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf auxtrace: Remove dummy tools

2024-08-12T21:04:36+00:00

Add perf_session__deliver_synth_attr_event that synthesizes a perf_record_header_attr event with one id. Remove use of perf_event__synthesize_attr that necessitates the use of the dummy tool in order to pass the session. Reviewed-by: Adrian Hunter Signed-off-by: Ian Rogers Tested-by: Adrian Hunter Tested-by: Leo Yan Cc: Alexander Shishkin Cc: Anshuman Khandual Cc: Athira Rajeev Cc: Huacai Chen Cc: Ilkka Koskinen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Jonathan Cameron Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Nick Desaulniers Cc: Nick Terrell Cc: Oliver Upton Cc: Peter Zijlstra Cc: Song Liu Cc: Sun Haiyong Cc: Suzuki Poulouse Cc: Will Deacon Cc: Yanteng Si Cc: Yicong Yang Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20240812204720.631678-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo