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2026-01-26perf thread: Add optional e_flags output argument to thread__e_machineIan Rogers
The e_flags are needed to accurately compute complete perf register information for CSKY. Add the ability to read and have this value associated with a thread. This change doesn't wire up the use of the e_flags except in disasm where use already exists but just wasn't set up yet. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Aditya Bodkhe <aditya.b1@linux.ibm.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.ibm.com> Cc: Chun-Tse Shao <ctshao@google.com> Cc: Guo Ren <guoren@kernel.org> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergei Trofimovich <slyich@gmail.com> Cc: Shimin Guo <shimin.guo@skydio.com> Cc: Stephen Brennan <stephen.s.brennan@oracle.com> Cc: Swapnil Sapkal <swapnil.sapkal@amd.com> Cc: Tianyou Li <tianyou.li@intel.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-20perf trace: Deal with compiler const checksArnaldo Carvalho de Melo
The strchr() function these days return const/non-const based on the arg it receives, and sometimes we need to use casts when we're dealing with variables that are used in code that needs to safely change the returned value and sometimes not (as it points to really const areas). Tweak one such case. Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-14perf tools: Switch printf("...%s", strerror(errno)) to printf("...%m")Ian Rogers
strerror() has thread safety issues, strerror_r() requires stack allocated buffers. Code in perf has already been using the "%m" formatting flag that is a widely support glibc extension to print the current errno's description. Expand the usage of this formatting flag and remove usage of strerror()/strerror_r(). Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Blake Jones <blakejones@google.com> Cc: Chun-Tse Shao <ctshao@google.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Dr. David Alan Gilbert <linux@treblig.org> Cc: Haibo Xu <haibo1.xu@intel.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Leo Yan <leo.yan@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Brennan <stephen.s.brennan@oracle.com> Cc: Thomas Falcon <thomas.falcon@intel.com> Cc: Yunseong Kim <ysk@kzalloc.com> Cc: Zhongqiu Han <quic_zhonhan@quicinc.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-12-17perf trace: Don't change const char stringsArnaldo Carvalho de Melo
We got away with this so far but now with fedora 44 complaining about the return value of strchr et all, lets use strdup for good measure. Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20251211221756.96294-5-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-11-29perf trace: Skip internal syscall argumentsNamhyung Kim
Recent changes in the linux-next kernel will add new field for syscalls to have contents in the userspace like below. # cat /sys/kernel/tracing/events/syscalls/sys_enter_write/format name: sys_enter_write ID: 758 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:int __syscall_nr; offset:8; size:4; signed:1; field:unsigned int fd; offset:16; size:8; signed:0; field:const char * buf; offset:24; size:8; signed:0; field:size_t count; offset:32; size:8; signed:0; field:__data_loc char[] __buf_val; offset:40; size:4; signed:0; print fmt: "fd: 0x%08lx, buf: 0x%08lx (%s), count: 0x%08lx", ((unsigned long)(REC->fd)), ((unsigned long)(REC->buf)), __print_dynamic_array(__buf_val, 1), ((unsigned long)(REC->count)) We have a different way to handle those arguments and this change confuses perf trace then make some tests failing. Fix it by skipping the new fields that have "__data_loc char[]" type. Maybe we can switch to this instead of the BPF augmentation later. Reviewed-by: Howard Chu <howardchu95@gmail.com> Tested-by: Thomas Richter <tmricht@linux.ibm.com> Tested-by: Steven Rostedt (Google) <rostedt@goodmis.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Howard Chu <howardchu95@gmail.com> Reported-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-10-19perf trace: Don't synthesize mmaps unless callchains are enabledIan Rogers
Synthesizing mmaps in perf trace is unnecessary unless call chains are being generated. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-09-19perf trace: Fix IS_ERR() vs NULL check bugFushuai Wang
The alloc_syscall_stats() function always returns an error pointer (ERR_PTR) on failure. So replace NULL check with IS_ERR() check after calling alloc_syscall_stats() function. Fixes: fc00897c8a3f7f57 ("perf trace: Add --summary-mode option") Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Fushuai Wang <wangfushuai@baidu.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-09-19perf trace: Add --max-summary optionNamhyung Kim
The --max-summary option is to limit the number of output lines for syscall summary stats. The max applies to each entries like thread and cgroups. For total summary, it will just print up to the given number. For example, $ sudo perf trace -as --max-summary 3 sleep 0.1 ThreadPoolServi (1011651), 114 events, 14.8% syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ epoll_wait 38 0 95.589 0.000 2.515 11.153 28.98% futex 9 0 0.040 0.002 0.004 0.014 28.63% read 10 0 0.037 0.003 0.004 0.005 4.67% sleep (1050529), 250 events, 32.4% syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ clock_nanosleep 1 0 100.156 100.156 100.156 100.156 0.00% execve 4 3 1.020 0.005 0.255 0.989 95.93% openat 36 17 0.416 0.003 0.012 0.029 10.58% ... And this is for per-cgroup summary using BPF. $ sudo perf trace -as --max-summary 3 --summary-mode=cgroup --bpf-summary sleep 0.1 cgroup /user.slice/user-657345.slice/user@657345.service/session.slice/org.gnome.Shell@x11.service, 12 events syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ recvmsg 8 7 0.016 0.001 0.002 0.006 39.73% ppoll 1 0 0.014 0.014 0.014 0.014 0.00% write 2 0 0.010 0.002 0.005 0.008 61.02% cgroup /user.slice/user-657345.slice/session-4.scope, 73 events syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ epoll_wait 8 0 13.461 0.010 1.683 12.235 89.66% ioctl 20 0 0.204 0.001 0.010 0.113 54.01% writev 11 0 0.164 0.004 0.015 0.042 20.34% Reviewed-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-07-25perf trace: Avoid global perf_env with evsel__envIan Rogers
There is no session in perf trace unless in replay mode, so in host mode no session can be associated with the evlist. If the evsel__env call fails resort to the host_env that's part of the trace. Remove errno_to_name as it becomes a called once 1-line function once the argument is turned into a perf_env, just call perf_env__arch_strerrno directly. Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250724163302.596743-19-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-07-25perf machine: Explicitly pass in host perf_envIan Rogers
When creating a machine for the host explicitly pass in a scoped perf_env. This removes a use of the global perf_env. Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250724163302.596743-17-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-07-25perf session: Add accessor for session->header.envIan Rogers
The perf_env from the header in the session is frequently accessed, add an accessor function rather than access directly. Cache the value to avoid repeated calls. No behavioral change. Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250724163302.596743-10-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-26perf trace: Split BPF skel code to util/bpf_trace_augment.cNamhyung Kim
And make builtin-trace.c less conditional. Dummy functions will be called when BUILD_BPF_SKEL=0 is used. This makes the builtin-trace.c slightly smaller and simpler by removing the skeleton and its helpers. The conditional guard of trace__init_syscalls_bpf_prog_array_maps() is changed from the HAVE_BPF_SKEL to HAVE_LIBBPF_SUPPORT as it doesn't have a skeleton in the code directly. And a dummy function is added so that it can be called unconditionally. The function will succeed only if the both conditions are true. Do not include trace_augment.h from the BPF code and move the definition of TRACE_AUG_MAX_BUF to the BPF directly. Reviewed-by: Howard Chu <howardchu95@gmail.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: https://lore.kernel.org/r/20250623225721.21553-1-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-24perf trace: Add missed freeing of ordered events and threadIan Rogers
Caught by leak sanitizer running "perf trace BTF general tests". Make the ordered_events initialization unconditional and early so that trace__exit cleanup is simple - ordered_events__init doesn't allocate and just sets up 4 values and inits 3 list heads. Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250617223356.2752099-3-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-24perf trace: Show zero value in STRARRAYNamhyung Kim
The STRARRAY macro is to print values in a pre-defined array. But sometimes it hides the value because it's 0. The value of 0 can have a meaning in this case so set 'show_zero' field. For example, it can show CREATE_MAP cmd in the bpf syscall. Acked-by: Howard Chu <howardchu95@gmail.com> Link: https://lore.kernel.org/r/20250502204056.973977-1-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-09perf target: Remove uid from targetIan Rogers
Gathering threads with a uid by scanning /proc is inherently racy leading to perf_event_open failures that quit perf. All users of the functionality now use BPF filters, so remove uid and uid_str from target. Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250604174545.2853620-10-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-09perf trace: Switch user option to use BPF filterIan Rogers
Finding user processes by scanning /proc is inherently racy and results in perf_event_open failures. Use a BPF filter to drop samples where the uid doesn't match. Ensure adding the BPF filter forces system-wide. Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250604174545.2853620-8-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-05-29perf trace: Set errpid to false for rseq and set_robust_listAnubhav Shelat
The 'rseq' and 'set_robust_list' syscalls don't return a pid, so set errpid for both to false. Fixes: 0c1019e3463b263a ("perf trace: Mark the 'rseq' arg in the rseq syscall as coming from user space") Fixes: 1de5b5dcb8353f36 ("perf trace: Mark the 'head' arg in the set_robust_list syscall as coming from user space") Signed-off-by: Anubhav Shelat <ashelat@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Dapeng Mi <dapeng1.mi@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250529143334.1469669-2-ashelat@redhat.com [ Remove explicit .errpid = false, omitting its initialization zeroes it, as noted by Namhyung ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-05-28perf trace: Always print return value for syscalls returning a pidAnubhav Shelat
The syscalls that were consistently observed were set_robust_list and rseq. This is because perf cannot find their child process. This change ensures that the return value is always printed. Before: 0.256 ( 0.001 ms): set_robust_list(head: 0x7f09c77dba20, len: 24) = 0.259 ( 0.001 ms): rseq(rseq: 0x7f09c77dc0e0, rseq_len: 32, sig: 1392848979) = After: 0.270 ( 0.002 ms): set_robust_list(head: 0x7f0bb14a6a20, len: 24) = 0 0.273 ( 0.002 ms): rseq(rseq: 0x7f0bb14a70e0, rseq_len: 32, sig: 1392848979) = 0 Committer notes: As discussed in the thread in the Link: tag below, these two don't return a pid, but for syscalls returning one, we need to print the result and if we manage to find the children in 'perf trace' data structures, then print its name as well. Fixes: 11c8e39f5133aed9 ("perf trace: Infrastructure to show COMM strings for syscalls returning PIDs") Reviewed-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Anubhav Shelat <ashelat@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Dapeng Mi <dapeng1.mi@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250403160411.159238-2-ashelat@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-05-13perf trace: Support --summary-mode=cgroupNamhyung Kim
Add a new summary mode to collect stats for each cgroup. $ sudo ./perf trace -as --bpf-summary --summary-mode=cgroup -- sleep 1 Summary of events: cgroup /user.slice/user-657345.slice/user@657345.service/session.slice/org.gnome.Shell@x11.service, 535 events syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ ppoll 15 0 373.600 0.004 24.907 197.491 55.26% poll 15 0 1.325 0.001 0.088 0.369 38.76% close 66 0 0.567 0.007 0.009 0.026 3.55% write 150 0 0.471 0.001 0.003 0.010 3.29% recvmsg 94 83 0.290 0.000 0.003 0.037 16.39% ioctl 26 0 0.237 0.001 0.009 0.096 50.13% timerfd_create 66 0 0.236 0.003 0.004 0.024 8.92% timerfd_settime 70 0 0.160 0.001 0.002 0.012 7.66% writev 10 0 0.118 0.001 0.012 0.019 18.17% read 9 0 0.021 0.001 0.002 0.004 14.07% getpid 14 0 0.019 0.000 0.001 0.004 20.28% cgroup /system.slice/polkit.service, 94 events syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ ppoll 22 0 19.811 0.000 0.900 9.273 63.88% write 30 0 0.040 0.001 0.001 0.003 12.09% recvmsg 12 0 0.018 0.001 0.002 0.006 28.15% read 18 0 0.013 0.000 0.001 0.003 21.99% poll 12 0 0.006 0.000 0.001 0.001 4.48% cgroup /user.slice/user-657345.slice/user@657345.service/app.slice/app-org.gnome.Terminal.slice/gnome-terminal-server.service, 21 events syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ ppoll 4 0 17.476 0.003 4.369 13.298 69.65% recvmsg 15 12 0.068 0.002 0.005 0.014 26.53% writev 1 0 0.033 0.033 0.033 0.033 0.00% poll 1 0 0.005 0.005 0.005 0.005 0.00% ... It works only for --bpf-summary for now. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20250501225337.928470-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-05-08perf trace: Fix leaks of 'struct thread' in set_filter_loop_pids()Namhyung Kim
I've found some leaks from 'perf trace -a'. It seems there are more leaks but this is what I can find for now. Fixes: 082ab9a18e532864 ("perf trace: Filter out 'sshd' in the tracer ancestry in syswide tracing") Reviewed-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250403054213.7021-1-namhyung@kernel.org [ split from a larget patch ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-05-08perf trace: Fix leaks of 'struct thread' in fprintf_sys_enter()Namhyung Kim
I've found some leaks from 'perf trace -a'. It seems there are more leaks but this is what I can find for now. Fixes: 70351029b55677eb ("perf thread: Add support for reading the e_machine type for a thread") Reviewed-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250403054213.7021-1-namhyung@kernel.org [ split from a larget patch ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-05-08perf trace: Free the files.max entry in files->tableIan Rogers
The files.max is the maximum valid fd in the files array and so freeing the values needs to be inclusive of the max value. Reviewed-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250401202715.3493567-1-irogers@google.com [ split from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-04-28perf trace: Implement syscall summary in BPFNamhyung Kim
When -s/--summary option is used, it doesn't need (augmented) arguments of syscalls. Let's skip the augmentation and load another small BPF program to collect the statistics in the kernel instead of copying the data to the ring-buffer to calculate the stats in userspace. This will be much more light-weight than the existing approach and remove any lost events. Let's add a new option --bpf-summary to control this behavior. I cannot make it default because there's no way to get e_machine in the BPF which is needed for detecting different ABIs like 32-bit compat mode. No functional changes intended except for no more LOST events. :) $ sudo ./perf trace -as --summary-mode=total --bpf-summary sleep 1 Summary of events: total, 6194 events syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ epoll_wait 561 0 4530.843 0.000 8.076 520.941 18.75% futex 693 45 4317.231 0.000 6.230 500.077 21.98% poll 300 0 1040.109 0.000 3.467 120.928 17.02% clock_nanosleep 1 0 1000.172 1000.172 1000.172 1000.172 0.00% ppoll 360 0 872.386 0.001 2.423 253.275 41.91% epoll_pwait 14 0 384.349 0.001 27.453 380.002 98.79% pselect6 14 0 108.130 7.198 7.724 8.206 0.85% nanosleep 39 0 43.378 0.069 1.112 10.084 44.23% ... Reviewed-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20250326044001.3503432-1-namhyung@kernel.org [ Added fixup sent from Namhyung in response to my report to make it also dependent on CONFIG_TRACE ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-03-24perf trace: Fix wrong size to bpf_map__update_elem callThomas Richter
In linux-next commit c760174401f6 ("perf cpumap: Reduce cpu size from int to int16_t") causes the perf tests 100 126 to fail on s390: Output before: # ./perf test 100 100: perf trace BTF general tests : FAILED! # The root cause is the change from int to int16_t for the cpu maps. The size of the CPU key value pair changes from four bytes to two bytes. However a two byte key size is not supported for bpf_map__update_elem(). Note: validate_map_op() in libbpf.c emits warning libbpf: map '__augmented_syscalls__': \ unexpected key size 2 provided, expected 4 when key size is set to int16_t. Therefore change to variable size back to 4 bytes for invocation of bpf_map__update_elem(). Output after: # ./perf test 100 100: perf trace BTF general tests : Ok # Fixes: c760174401f6 ("perf cpumap: Reduce cpu size from int to int16_t") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Ian Rogers <irogers@google.com> Acked-by: Howard Chu <howardchu95@gmail.com> Cc: James Clark <james.clark@linaro.org> Link: https://lore.kernel.org/r/20250324152756.3879571-1-tmricht@linux.ibm.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-20perf trace: Fix evlist memory leakIan Rogers
Leak sanitizer was reporting a memory leak in the "perf record and replay" test. Add evlist__delete to trace__exit, also ensure trace__exit is called after trace__record. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org> Link: https://lore.kernel.org/r/20250319050741.269828-15-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-20perf trace: Fix BTF memory leakIan Rogers
Add missing btf__free in trace__exit. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org> Link: https://lore.kernel.org/r/20250319050741.269828-14-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-20perf trace: Make syscall table stableIan Rogers
Namhyung fixed the syscall table being reallocated and moving by reloading the system call pointer after a move: https://lore.kernel.org/lkml/Z9YHCzINiu4uBQ8B@google.com/ This could be brittle so this patch changes the syscall table to be an array of pointers of "struct syscall" that don't move. Remove unnecessary copies and searches with this change. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org> Link: https://lore.kernel.org/r/20250319050741.269828-13-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-20perf thread: Add support for reading the e_machine type for a threadIan Rogers
First try to read the e_machine from the dsos associated with the thread's maps. If live use the executable from /proc/pid/exe and read the e_machine from the ELF header. On failure use EM_HOST. Change builtin-trace syscall functions to pass e_machine from the thread rather than EM_HOST, so that in later patches when syscalltbl can use the e_machine the system calls are specific to the architecture. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org> Link: https://lore.kernel.org/r/20250319050741.269828-8-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-20perf syscalltbl: Remove struct syscalltblIan Rogers
The syscalltbl held entries of system call name and number pairs, generated from a native syscalltbl at start up. As there are gaps in the system call number there is a notion of index into the table. Going forward we want the system call table to be identifiable by a machine type, for example, i386 vs x86-64. Change the interface to the syscalltbl so (1) a (currently unused machine type of EM_HOST) is passed (2) the index to syscall number and system call name mapping is computed at build time. Two tables are used for this, an array of system call number to name, an array of system call numbers sorted by the system call name. The sorted array doesn't store strings in part to save memory and relocations. The index notion is carried forward and is an index into the sorted array of system call numbers, the data structures are opaque (held only in syscalltbl.c), and so the number of indices for a machine type is exposed as a new API. The arrays are computed in the syscalltbl.sh script and so no start-up time computation and storage is necessary. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Howard Chu <howardchu95@gmail.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org> Link: https://lore.kernel.org/r/20250319050741.269828-6-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-20perf trace: Reorganize syscallsIan Rogers
Identify struct syscall information in the syscalls table by a machine type and syscall number, not just system call number. Having the machine type means that 32-bit system calls can be differentiated from 64-bit ones on a machine capable of both. Having a table for all machine types and all system call numbers would be too large, so maintain a sorted array of system calls as they are encountered. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Howard Chu <howardchu95@gmail.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org> Link: https://lore.kernel.org/r/20250319050741.269828-5-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-27perf trace: Add missing perf_tool__init()Athira Rajeev
Perf trace on perf.data fails as below: ./perf trace record -- sleep 1 ./perf trace -i perf.data perf: Segmentation fault Segmentation fault (core dumped) Backtrace pointed to : ?? () perf_session.process_user_event () reader.read_event () perf_session.process_events () cmd_trace () run_builtin () handle_internal_command () main () Further debug pointed that, segmentation fault happens when trying to access id_index. Code snippet: case PERF_RECORD_ID_INDEX: err = tool->id_index(session, event); Since 'commit 15d4a6f41d72 ("perf tool: Remove perf_tool__fill_defaults()")', perf_tool__fill_defaults is removed. All tools are initialized using perf_tool__init() prior to use. But in builtin-trace, perf_tool__init is not used and hence the defaults are not initialized. Use perf_tool__init() in perf trace to handle the initialization. Reported-by: Tejas Manhas <Tejas.Manhas1@ibm.com> Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com> Link: https://lore.kernel.org/r/20250225113157.28836-1-atrajeev@linux.ibm.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-12perf sample: Make user_regs and intr_regs optionalIan Rogers
The struct dump_regs contains 512 bytes of cache_regs, meaning the two values in perf_sample contribute 1088 bytes of its total 1384 bytes size. Initializing this much memory has a cost reported by Tavian Barnes <tavianator@tavianator.com> as about 2.5% when running `perf script --itrace=i0`: https://lore.kernel.org/lkml/d841b97b3ad2ca8bcab07e4293375fb7c32dfce7.1736618095.git.tavianator@tavianator.com/ Adrian Hunter <adrian.hunter@intel.com> replied that the zero initialization was necessary and couldn't simply be removed. This patch aims to strike a middle ground of still zeroing the perf_sample, but removing 79% of its size by make user_regs and intr_regs optional pointers to zalloc-ed memory. To support the allocation accessors are created for user_regs and intr_regs. To support correct cleanup perf_sample__init and perf_sample__exit functions are created and added throughout the code base. Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250113194345.1537821-1-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-12perf trace: Add --summary-mode optionNamhyung Kim
The --summary-mode option will select how to show the syscall summary at the end. By default, it'll show the summary for each thread and it's the same as if --summary-mode=thread is passed. The other option is to show total summary, which is --summary-mode=total. I'd like to have this instead of a separate option like --total-summary because we may want to add a new summary mode (by cgroup) later. $ sudo ./perf trace -as --summary-mode=total sleep 1 Summary of events: total, 21580 events syscall calls errors total min avg max stddev (msec) (msec) (msec) (msec) (%) --------------- -------- ------ -------- --------- --------- --------- ------ epoll_wait 1305 0 14716.712 0.000 11.277 551.529 8.87% futex 1256 89 13331.197 0.000 10.614 733.722 15.49% poll 669 0 6806.618 0.000 10.174 459.316 11.77% ppoll 220 0 3968.797 0.000 18.040 516.775 25.35% clock_nanosleep 1 0 1000.027 1000.027 1000.027 1000.027 0.00% epoll_pwait 21 0 592.783 0.000 28.228 522.293 88.29% nanosleep 16 0 60.515 0.000 3.782 10.123 33.33% ioctl 510 0 4.284 0.001 0.008 0.182 8.84% recvmsg 1434 775 3.497 0.001 0.002 0.174 6.37% write 1393 0 2.854 0.001 0.002 0.017 1.79% read 1063 100 2.236 0.000 0.002 0.083 5.11% ... Reviewed-by: Howard Chu <howardchu95@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: https://lore.kernel.org/r/20250205205443.1986408-5-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-12perf trace: Convert syscall_stats to hashmapNamhyung Kim
It was using a RBtree-based int-list as a hash and a custom resort logic for that. As we have hashmap, let's convert to it and add a custom sort function for the hashmap entries using an array. It should be faster and more light-weighted. It's also to prepare supporting system-wide syscall stats. No functional changes intended. Reviewed-by: Howard Chu <howardchu95@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: https://lore.kernel.org/r/20250205205443.1986408-3-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-12perf trace: Allocate syscall stats only if summary is onNamhyung Kim
The syscall stats are used only when summary is requested. Let's avoid unnecessary operations. While at it, let's pass 'trace' pointer directly instead of passing 'output' file pointer and 'summary' option in the 'trace' separately. Reviewed-by: Howard Chu <howardchu95@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: https://lore.kernel.org/r/20250205205443.1986408-2-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-05Merge tag 'v6.14-rc1' into perf-tools-nextNamhyung Kim
To get the various fixes in the current master. Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-01-28perf trace: Fix runtime error of index out of boundsHoward Chu
libtraceevent parses and returns an array of argument fields, sometimes larger than RAW_SYSCALL_ARGS_NUM (6) because it includes "__syscall_nr", idx will traverse to index 6 (7th element) whereas sc->fmt->arg holds 6 elements max, creating an out-of-bounds access. This runtime error is found by UBsan. The error message: $ sudo UBSAN_OPTIONS=print_stacktrace=1 ./perf trace -a --max-events=1 builtin-trace.c:1966:35: runtime error: index 6 out of bounds for type 'syscall_arg_fmt [6]' #0 0x5c04956be5fe in syscall__alloc_arg_fmts /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:1966 #1 0x5c04956c0510 in trace__read_syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2110 #2 0x5c04956c372b in trace__syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2436 #3 0x5c04956d2f39 in trace__init_syscalls_bpf_prog_array_maps /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:3897 #4 0x5c04956d6d25 in trace__run /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:4335 #5 0x5c04956e112e in cmd_trace /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:5502 #6 0x5c04956eda7d in run_builtin /home/howard/hw/linux-perf/tools/perf/perf.c:351 #7 0x5c04956ee0a8 in handle_internal_command /home/howard/hw/linux-perf/tools/perf/perf.c:404 #8 0x5c04956ee37f in run_argv /home/howard/hw/linux-perf/tools/perf/perf.c:448 #9 0x5c04956ee8e9 in main /home/howard/hw/linux-perf/tools/perf/perf.c:556 #10 0x79eb3622a3b7 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 #11 0x79eb3622a47a in __libc_start_main_impl ../csu/libc-start.c:360 #12 0x5c04955422d4 in _start (/home/howard/hw/linux-perf/tools/perf/perf+0x4e02d4) (BuildId: 5b6cab2d59e96a4341741765ad6914a4d784dbc6) 0.000 ( 0.014 ms): Chrome_ChildIO/117244 write(fd: 238, buf: !, count: 1) = 1 Fixes: 5e58fcfaf4c6 ("perf trace: Allow allocating sc->arg_fmt even without the syscall tracepoint") Signed-off-by: Howard Chu <howardchu95@gmail.com> Link: https://lore.kernel.org/r/20250122025519.361873-1-howardchu95@gmail.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-01-24perf trace: Fix return value of trace__fprintf_tp_fieldsBenjamin Peterson
This function formerly returned twice the number of bytes printed. Signed-off-by: Benjamin Peterson <benjamin@engflow.com> Reviewed-by: Howard Chu <howardchu95@gmail.com> Link: https://lore.kernel.org/r/20250123-void-fprintf_tp_fields-v2-1-6038f8224987@engflow.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-01-10perf trace: Fix unaligned access for augmented argsNamhyung Kim
Some version of compilers reported unaligned accesses in perf trace when undefined-behavior sanitizer is on. I found that it uses raw data in the sample directly and assuming it's properly aligned. Unlike other sample fields, the raw data is not 8-byte aligned because there's a size field (u32) before the actual data. So I added a static buffer in syscall__augmented_args() and return it instead. This is not ideal but should work well as perf trace is single-threaded. A better approach would be aligning the raw data by adding a 4-byte data before the augmented args but I'm afraid it'd break the backward compatibility. Committer testing: To build with the undefined behaviour sanitizer: $ make CC=clang EXTRA_CFLAGS=-fsanitize=undefined -C tools/perf Checking if the resulting binary is instrumented: root@number:~# nm ~/bin/perf | grep ubsan | wc -l 113 root@number:~# nm ~/bin/perf | grep ubsan | tail -5 000000000043d5b0 t _ZN7__ubsanL19UBsanOnDeadlySignalEiPvS0_ 000000000043ce50 T _ZNK7__ubsan5Value12getSIntValueEv 000000000043cf40 T _ZNK7__ubsan5Value12getUIntValueEv 000000000043d140 T _ZNK7__ubsan5Value13getFloatValueEv 000000000043cfd0 T _ZNK7__ubsan5Value19getPositiveIntValueEv root@number:~# Now running something that will access timespec, as reported in the Closes URL: root@number:~# perf trace --max-events=1 -e *nano* sleep 1.1 trace/beauty/timespec.c:10:64: runtime error: member access within misaligned address 0x7fc583cfb2a4 for type 'struct augmented_arg', which requires 8 byte alignment 0x7fc583cfb2a4: note: pointer points here 99 99 11 00 10 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 01 e1 f5 05 00 00 00 00 00 00 00 00 ^ SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior trace/beauty/timespec.c:10:64 <SNIP> As Namhyung said we need to make the raw_data to be 64-bit aligned, probably we need to add a PERF_SAMPLE_ALIGNED_RAW with a 64-bit raw_size instead of the current u32 done at kernel/events/core.c, perf_output_sample(), that perf_output_put(handle, raw->size) where raw->size is an u32 and then the raw_data is always 64-bit unaligned... After the patch: root@number:~# perf trace -e *nano* sleep 1.1 0.000 (1100.064 ms): sleep/1984224 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 100000001 }, rmtp: 0x7fff5b3fe970) = 0 root@number:~# Closes: https://lore.kernel.org/r/Z2STgyD1p456Qqhg@google.com Reviewed-by: Howard Chu <howardchu95@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250102201248.790841-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-01-10perf tools: Remove dependency on libauditCharlie Jenkins
All architectures now support HAVE_SYSCALL_TABLE_SUPPORT, so the flag is no longer needed. With the removal of the flag, the related GENERIC_SYSCALL_TABLE can also be removed. libaudit was only used as a fallback for when HAVE_SYSCALL_TABLE_SUPPORT was not defined, so libaudit is also no longer needed for any architecture. Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christian Brauner <brauner@kernel.org> Cc: Guo Ren <guoren@kernel.org> Cc: Günther Noack <gnoack@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leo Yan <leo.yan@linux.dev> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mickaël Salaün <mic@digikod.net> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-16-7543b5293098@rivosinc.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-12-18perf env: Move arch errno function to only use in envIan Rogers
Move arch_syscalls__strerrno_function out of builtin-trace.c to env.c so that there isn't a util to builtin function call. This allows the python.c stub to be removed. Also, remove declaration/prototype from env.h and make static to reduce scope. The include is moved inside ifdefs to avoid, "defined but unused warnings". Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dapeng Mi <dapeng1.mi@linux.intel.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Veronika Molnarova <vmolnaro@redhat.com> Cc: Weilin Wang <weilin.wang@intel.com> Link: https://lore.kernel.org/r/20241119011644.971342-15-irogers@google.com perf: perf python: Correctly throw IndexError Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-12-09perf evsel: Add/use accessor for tp_formatIan Rogers
Add an accessor function for tp_format. Rather than search+replace uses try to use a variable and reuse it. Add additional NULL checks when accessing/using the value. Make sure the PTR_ERR is nulled out on error path in evsel__newtp_idx. Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Ben Gainey <ben.gainey@arm.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dominique Martinet <asmadeus@codewreck.org> Cc: Ilkka Koskinen <ilkka@os.amperecomputing.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Thomas Falcon <thomas.falcon@intel.com> Cc: Weilin Wang <weilin.wang@intel.com> Cc: Yang Jihong <yangjihong@bytedance.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Ze Gao <zegao2021@gmail.com> Cc: Zixian Cai <fzczx123@gmail.com> Cc: zhaimingbing <zhaimingbing@cmss.chinamobile.com> Link: https://lore.kernel.org/r/20241118225345.889810-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-11-14perf trace: Avoid garbage when not printing a syscall's argumentsBenjamin Peterson
syscall__scnprintf_args may not place anything in the output buffer (e.g., because the arguments are all zero). If that happened in trace__fprintf_sys_enter, its fprintf would receive an unitialized buffer leading to garbage output. Fix the problem by passing the (possibly zero) bounds of the argument buffer to the output fprintf. Fixes: a98392bb1e169a04 ("perf trace: Use beautifiers on syscalls:sys_enter_ handlers") Signed-off-by: Benjamin Peterson <benjamin@engflow.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Howard Chu <howardchu95@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20241107232128.108981-2-benjamin@engflow.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-11-14perf trace: Do not lose last events in a raceBenjamin Peterson
If a perf trace event selector specifies a maximum number of events to output (i.e., "/nr=N/" syntax), the event printing handler, trace__event_handler, disables the event selector after the maximum number events are printed. Furthermore, trace__event_handler checked if the event selector was disabled before doing any work. This avoided exceeding the maximum number of events to print if more events were in the buffer before the selector was disabled. However, the event selector can be disabled for reasons other than exceeding the maximum number of events. In particular, when the traced subprocess exits, the main loop disables all event selectors. This meant the last events of a traced subprocess might be lost to the printing handler's short-circuiting logic. This nondeterministic problem could be seen by running the following many times: $ perf trace -e syscalls:sys_enter_exit_group true trace__event_handler should simply check for exceeding the maximum number of events to print rather than the state of the event selector. Fixes: a9c5e6c1e9bff42c ("perf trace: Introduce per-event maximum number of events property") Signed-off-by: Benjamin Peterson <benjamin@engflow.com> Tested-by: Howard Chu <howardchu95@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20241107232128.108981-1-benjamin@engflow.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-11-14perf trace: Fix tracing itself, creating feedback loopsHoward Chu
There exists a pids_filtered map in augmented_raw_syscalls.bpf.c that ceases to provide functionality after the BPF skeleton migration done in: 5e6da6be3082f77b ("perf trace: Migrate BPF augmentation to use a skeleton") Before the migration, pid_filtered map works, courtesy of Arnaldo Carvalho de Melo <acme@kernel.org>: ⬢ [acme@toolbox perf-tools]$ git log --oneline -5 6f769c3458b6cf2d (HEAD) perf tests trace+probe_vfs_getname.sh: Accept quotes surrounding the filename 7777ac3dfe29f55d perf test trace+probe_vfs_getname.sh: Remove stray \ before / 33d9c5062113a4bd perf script python: Add stub for PMU symbol to the python binding e59fea47f83e8a9a perf symbols: Fix DSO kernel load and symbol process to correctly map DSO to its long_name, type and adjust_symbols 878460e8d0ff84a0 perf build: Remove -Wno-unused-but-set-variable from the flex flags when building with clang < 13.0.0 root@x1:/home/acme/git/perf-tools# perf trace -e /tmp/augmented_raw_syscalls.o -e write* --max-events=30 & [1] 180632 root@x1:/home/acme/git/perf-tools# 0.000 ( 0.051 ms): NetworkManager/1127 write(fd: 3, buf: 0x7ffeb508ef70, count: 8) = 8 0.115 ( 0.010 ms): NetworkManager/1127 write(fd: 3, buf: 0x7ffeb508ef70, count: 8) = 8 0.916 ( 0.068 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 246) = 246 1.699 ( 0.047 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 2.167 ( 0.041 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 2.739 ( 0.042 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 3.138 ( 0.027 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 3.477 ( 0.027 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 3.738 ( 0.023 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 3.946 ( 0.024 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 4.195 ( 0.024 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 121) = 121 4.212 ( 0.026 ms): NetworkManager/1127 write(fd: 3, buf: 0x7ffeb508ef70, count: 8) = 8 4.285 ( 0.006 ms): NetworkManager/1127 write(fd: 3, buf: 0x7ffeb508ef70, count: 8) = 8 4.445 ( 0.018 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 260) = 260 4.508 ( 0.009 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 124) = 124 4.592 ( 0.010 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 116) = 116 4.666 ( 0.009 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 130) = 130 4.715 ( 0.010 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 95) = 95 4.765 ( 0.007 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 102) = 102 4.815 ( 0.009 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 79) = 79 4.890 ( 0.008 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 57) = 57 4.937 ( 0.007 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 89) = 89 5.009 ( 0.010 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 112) = 112 5.059 ( 0.010 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 112) = 112 5.116 ( 0.007 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 79) = 79 5.152 ( 0.009 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 33) = 33 5.215 ( 0.008 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 37) = 37 5.293 ( 0.010 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 128) = 128 5.339 ( 0.009 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 89) = 89 5.384 ( 0.008 ms): sudo/156867 write(fd: 8, buf: 0x55cb4cd2f650, count: 100) = 100 [1]+ Done perf trace -e /tmp/augmented_raw_syscalls.o -e write* --max-events=30 root@x1:/home/acme/git/perf-tools# No events for the 'perf trace' (pid 180632), i.e. no feedback loop. If we leave it running: root@x1:/home/acme/git/perf-tools# perf trace -e /tmp/augmented_raw_syscalls.o -e landlock_add_rule & [1] 181068 root@x1:/home/acme/git/perf-tools# And then look at what maps it sets up: root@x1:/home/acme/git/perf-tools# bpftool map | grep pids_filtered -A3 1190: hash name pids_filtered flags 0x0 key 4B value 1B max_entries 64 memlock 7264B btf_id 1613 pids perf(181068) root@x1:/home/acme/git/perf-tools# And ask for dumping its contents: We see that we are _also_ setting it to filter those: root@x1:/home/acme/git/perf-tools# bpftool map dump id 1190 [{ "key": 181068, "value": 1 },{ "key": 156801, "value": 1 } ] Now testing the migration commit: perf $ git log commit 5e6da6be3082f77be06894a1a94d52a90b4007dc (HEAD) Author: Ian Rogers <irogers@google.com> Date: Thu Aug 10 11:48:51 2023 -0700 perf trace: Migrate BPF augmentation to use a skeleton perf $ ./perf trace -e write --max-events=10 & echo #! [1] 1808653 perf $ 0.000 ( 0.010 ms): :1808671/1808671 write(fd: 1, buf: 0x6003f5b26fc0, count: 11) = 11 0.162 ( ): perf/1808653 write(fd: 2, buf: 0x7fffc2174e50, count: 11) ... 0.174 ( ): perf/1808653 write(fd: 2, buf: 0x74ce21804563, count: 1) ... 0.184 ( ): perf/1808653 write(fd: 2, buf: 0x57b936589052, count: 5) The feedback loop is there. Keep it running, look into the bpf map: perf $ bpftool map | grep pids_filtered 10675: hash name pids_filtered flags 0x0 perf $ bpftool map dump id 10675 [] The map is empty. Now, this commit: 64917f4df048a064 ("perf trace: Use heuristic when deciding if a syscall tracepoint "const char *" field is really a string") Temporarily fixed the feedback loop for perf trace -e write, that's because before using the heuristic, write is hooked to sys_enter_openat: perf $ git log commit 83a0943b1870944612a8aa0049f910826ebfd4f7 (HEAD) Author: Arnaldo Carvalho de Melo <acme@redhat.com> Date: Thu Aug 17 12:11:51 2023 -0300 perf trace: Use the augmented_raw_syscall BPF skel only for tracing syscalls perf $ ./perf trace -e write --max-events=10 -v 2>&1 | grep Reusing Reusing "openat" BPF sys_enter augmenter for "write" And after the heuristic fix, it's unaugmented: perf $ git log commit 64917f4df048a0649ea7901c2321f020e71e6f24 (HEAD) Author: Arnaldo Carvalho de Melo <acme@redhat.com> Date: Thu Aug 17 15:14:21 2023 -0300 perf trace: Use heuristic when deciding if a syscall tracepoint "const char *" field is really a string perf $ ./perf trace -e write --max-events=10 -v 2>&1 | grep Reusing perf $ After using the heuristic, write is hooked to syscall_unaugmented, which returns 1. SEC("tp/raw_syscalls/sys_enter") int syscall_unaugmented(struct syscall_enter_args *args) { return 1; } If the BPF program returns 1, the tracepoint filter will filter it (since the tracepoint filter for perf is correctly set), but before the heuristic, when it was hooked to a sys_enter_openat(), which is a BPF program that calls bpf_perf_event_output() and writes to the buffer, it didn't get filtered, thus creating feedback loop. So switching write to unaugmented accidentally fixed the problem. But some syscalls are not so lucky, for example newfstatat: perf $ ./perf trace -e newfstatat --max-events=100 & echo #! [1] 2166948 457.718 ( ): perf/2166948 newfstatat(dfd: CWD, filename: "/proc/self/ns/mnt", statbuf: 0x7fff0132a9f0) ... 457.749 ( ): perf/2166948 newfstatat(dfd: CWD, filename: "/proc/2166950/ns/mnt", statbuf: 0x7fff0132aa80) ... 457.962 ( ): perf/2166948 newfstatat(dfd: CWD, filename: "/proc/self/ns/mnt", statbuf: 0x7fff0132a9f0) ... Currently, write is augmented by the new BTF general augmenter (which calls bpf_perf_event_output()). The problem, which luckily got fixed, resurfaced, and that’s how it was discovered. Fixes: 5e6da6be3082f77b ("perf trace: Migrate BPF augmentation to use a skeleton") Signed-off-by: Howard Chu <howardchu95@gmail.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20241030052431.2220130-1-howardchu95@gmail.com [ Check if trace->skel is non-NULL, as it is only initialized if trace->trace_syscalls is set ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-11-08perf build: Include libtraceevent headers directly indicated by pkg-configYicong Yang
Currently the libtraceevent's found by pkg-config, which give the include path as: [root@localhost tmp]# pkg-config --cflags libtraceevent -I/usr/local/include/traceevent So we should include the libtraceevent headers directly without "traceevent/" prefix. Update all the users. Fixes: 0f0e1f445690 ("perf build: Use pkg-config for feature check for libtrace{event,fs}") Suggested-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/linux-perf-users/ZyF5_Hf1iL01kldE@google.com/ Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Cc: leo.yan@arm.com Cc: amadio@gentoo.org Cc: linuxarm@huawei.com Link: https://lore.kernel.org/r/20241105105649.45399-1-yangyicong@huawei.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-11-05perf trace: avoid garbage when not printing a trace event's argumentsBenjamin Peterson
trace__fprintf_tp_fields may not print any tracepoint arguments. E.g., if the argument values are all zero. Previously, this would result in a totally uninitialized buffer being passed to fprintf, which could lead to garbage on the console. Fix the problem by passing the number of initialized bytes fprintf. Fixes: f11b2803bb88 ("perf trace: Allow choosing how to augment the tracepoint arguments") Signed-off-by: Benjamin Peterson <benjamin@engflow.com> Tested-by: Howard Chu <howardchu95@gmail.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: https://lore.kernel.org/r/20241103204816.7834-1-benjamin@engflow.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-11-03Merge 'origin/master' into perf-tools-nextNamhyung Kim
To get the fixes in the perf-tools branch. Resolved a conflict due to RISC-V's syscall table change. Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-10-17perf color: Add printf format checking and resolve issuesIan Rogers
Add printf format checking to vararg printf routines in color.h. Resolve build errors/bugs that are found through this checking. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Yicong Yang <yangyicong@hisilicon.com> Cc: Weilin Wang <weilin.wang@intel.com> Cc: Will Deacon <will@kernel.org> Cc: James Clark <james.clark@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Leo Yan <leo.yan@linux.dev> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: John Garry <john.g.garry@oracle.com> Link: https://lore.kernel.org/r/20241017175356.783793-2-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-10-17perf trace: The return from 'write' isn't a pidArnaldo Carvalho de Melo
When adding a explicit beautifier for the 'write' syscall when the BPF based buffer collector was introduced there was a cut'n'paste error that carried the syscall_fmt->errpid setting from a nearby syscall (waitid) that returns a pid. So the write return was being suppressed by the return pretty printer, remove that field, reverting it back to the default return handler, that prints positive numbers as-is and interpret negative values as errnos. I actually introduced the problem while making Howard's original patch work just with the 'write' syscall, as we couldn't just look for any buffers, the ones that are filled in by the kernel couldn't use the same sys_enter BPF collector. Fixes: b257fac12f38d7f5 ("perf trace: Pretty print buffer data") Reported-by: James Clark <james.clark@linaro.org> Link: https://lore.kernel.org/lkml/bcf50648-3c7e-4513-8717-0d14492c53b9@linaro.org Link: https://lore.kernel.org/all/Zt8jTfzDYgBPvFCd@x1/#t Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alan Maguire <alan.maguire@oracle.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>