From 83d7f5f1ad0ec6072bb5b4ca32795f0c199424e2 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Fri, 30 Apr 2021 10:03:02 +0300 Subject: [PATCH] perf inject: Add --vm-time-correlation option Intel PT timestamps are affected by virtualization. Add a new option that will allow the Intel PT decoder to correlate the timestamps and translate the virtual machine timestamps to host timestamps. The advantages of making this a separate step, rather than a part of normal decoding are that it is simpler to implement, and it needs to be done only once. This patch adds only the option. Later patches add Intel PT support. Signed-off-by: Adrian Hunter Reviewed-by: Andi Kleen Cc: Jiri Olsa Link: https://lore.kernel.org/r/20210430070309.17624-6-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-inject.txt | 10 ++++++++ tools/perf/builtin-inject.c | 44 ++++++++++++++++++++++++++++++++ tools/perf/util/auxtrace.h | 6 +++++ 3 files changed, 60 insertions(+) diff --git a/tools/perf/Documentation/perf-inject.txt b/tools/perf/Documentation/perf-inject.txt index a8eccff..91108fe 100644 --- a/tools/perf/Documentation/perf-inject.txt +++ b/tools/perf/Documentation/perf-inject.txt @@ -68,6 +68,16 @@ include::itrace.txt[] --force:: Don't complain, do it. +--vm-time-correlation[=OPTIONS]:: + Some architectures may capture AUX area data which contains timestamps + affected by virtualization. This option will update those timestamps + in place, to correlate with host timestamps. The in-place update means + that an output file is not specified, and instead the input file is + modified. The options are architecture specific, except that they may + start with "dry-run" which will cause the file to be processed but + without updating it. Currently this option is supported only by + Intel PT, refer linkperf:perf-intel-pt[1] + SEE ALSO -------- linkperf:perf-record[1], linkperf:perf-report[1], linkperf:perf-archive[1], diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c index 6007f18..102cafb 100644 --- a/tools/perf/builtin-inject.c +++ b/tools/perf/builtin-inject.c @@ -31,6 +31,7 @@ #include /* To get things like MAP_HUGETLB even on older libc headers */ #include +#include #include #include @@ -698,6 +699,36 @@ static void strip_init(struct perf_inject *inject) evsel->handler = drop_sample; } +static int parse_vm_time_correlation(const struct option *opt, const char *str, int unset) +{ + struct perf_inject *inject = opt->value; + const char *args; + char *dry_run; + + if (unset) + return 0; + + inject->itrace_synth_opts.set = true; + inject->itrace_synth_opts.vm_time_correlation = true; + inject->in_place_update = true; + + if (!str) + return 0; + + dry_run = skip_spaces(str); + if (!strncmp(dry_run, "dry-run", strlen("dry-run"))) { + inject->itrace_synth_opts.vm_tm_corr_dry_run = true; + inject->in_place_update_dry_run = true; + args = dry_run + strlen("dry-run"); + } else { + args = str; + } + + inject->itrace_synth_opts.vm_tm_corr_args = strdup(args); + + return inject->itrace_synth_opts.vm_tm_corr_args ? 0 : -ENOMEM; +} + static int __cmd_inject(struct perf_inject *inject) { int ret = -EINVAL; @@ -739,6 +770,15 @@ static int __cmd_inject(struct perf_inject *inject) else if (!strncmp(name, "sched:sched_stat_", 17)) evsel->handler = perf_inject__sched_stat; } + } else if (inject->itrace_synth_opts.vm_time_correlation) { + session->itrace_synth_opts = &inject->itrace_synth_opts; + memset(&inject->tool, 0, sizeof(inject->tool)); + inject->tool.id_index = perf_event__process_id_index; + inject->tool.auxtrace_info = perf_event__process_auxtrace_info; + inject->tool.auxtrace = perf_event__process_auxtrace; + inject->tool.auxtrace_error = perf_event__process_auxtrace_error; + inject->tool.ordered_events = true; + inject->tool.ordering_requires_timestamps = true; } else if (inject->itrace_synth_opts.set) { session->itrace_synth_opts = &inject->itrace_synth_opts; inject->itrace_synth_opts.inject = true; @@ -880,6 +920,9 @@ int cmd_inject(int argc, const char **argv) itrace_parse_synth_opts), OPT_BOOLEAN(0, "strip", &inject.strip, "strip non-synthesized events (use with --itrace)"), + OPT_CALLBACK_OPTARG(0, "vm-time-correlation", &inject, NULL, "opts", + "correlate time between VM guests and the host", + parse_vm_time_correlation), OPT_END() }; const char * const inject_usage[] = { @@ -968,5 +1011,6 @@ int cmd_inject(int argc, const char **argv) out_delete: zstd_fini(&(inject.session->zstd_data)); perf_session__delete(inject.session); + free(inject.itrace_synth_opts.vm_tm_corr_args); return ret; } diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h index 59c3c05..9ac2ac1 100644 --- a/tools/perf/util/auxtrace.h +++ b/tools/perf/util/auxtrace.h @@ -90,6 +90,9 @@ enum itrace_period_type { * @remote_access: whether to synthesize remote access events * @mem: whether to synthesize memory events * @timeless_decoding: prefer "timeless" decoding i.e. ignore timestamps + * @vm_time_correlation: perform VM Time Correlation + * @vm_tm_corr_dry_run: VM Time Correlation dry-run + * @vm_tm_corr_args: VM Time Correlation implementation-specific arguments * @callchain_sz: maximum callchain size * @last_branch_sz: branch context size * @period: 'instructions' events period @@ -130,6 +133,9 @@ struct itrace_synth_opts { bool remote_access; bool mem; bool timeless_decoding; + bool vm_time_correlation; + bool vm_tm_corr_dry_run; + char *vm_tm_corr_args; unsigned int callchain_sz; unsigned int last_branch_sz; unsigned long long period; -- 2.7.4