Re: [PATCH] perf record: Add support to collect callchains from kernel or user space only.

From: çèé
Date: Thu Jun 06 2019 - 02:10:03 EST


PING


ufo19890607 <ufo19890607@xxxxxxxxx> ä2019å5æ30æåå äå9:29åéï
>
> From: yuzhoujian <yuzhoujian@xxxxxxxxxxxxxxx>
>
> One can just record callchains in the kernel or user space with
> this new options. We can use it together with "--all-kernel" options.
> This two options is used just like print_stack(sys) or print_ustack(usr)
> for systemtap.
>
> Show below is the usage of this new option combined with "--all-kernel"
> options.
> 1. Configure all used events to run in kernel space and just
> collect kernel callchains.
> $ perf record -a -g --all-kernel --kernel-callchains
> 2. Configure all used events to run in kernel space and just
> collect user callchains.
> $ perf record -a -g --all-kernel --user-callchains
>
> Signed-off-by: yuzhoujian <yuzhoujian@xxxxxxxxxxxxxxx>
> ---
> tools/perf/Documentation/perf-record.txt | 6 ++++++
> tools/perf/builtin-record.c | 4 ++++
> tools/perf/perf.h | 2 ++
> tools/perf/util/evsel.c | 4 ++++
> 4 files changed, 16 insertions(+)
>
> diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
> index de269430720a..b647eb3db0c6 100644
> --- a/tools/perf/Documentation/perf-record.txt
> +++ b/tools/perf/Documentation/perf-record.txt
> @@ -490,6 +490,12 @@ Configure all used events to run in kernel space.
> --all-user::
> Configure all used events to run in user space.
>
> +--kernel-callchains::
> +Collect callchains from kernel space.
> +
> +--user-callchains::
> +Collect callchains from user space.
> +
> --timestamp-filename
> Append timestamp to output file name.
>
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index e2c3a585a61e..dca55997934e 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -2191,6 +2191,10 @@ static struct option __record_options[] = {
> OPT_BOOLEAN_FLAG(0, "all-user", &record.opts.all_user,
> "Configure all used events to run in user space.",
> PARSE_OPT_EXCLUSIVE),
> + OPT_BOOLEAN(0, "kernel-callchains", &record.opts.kernel_callchains,
> + "collect kernel callchains"),
> + OPT_BOOLEAN(0, "user-callchains", &record.opts.user_callchains,
> + "collect user callchains"),
> OPT_STRING(0, "clang-path", &llvm_param.clang_path, "clang path",
> "clang binary to use for compiling BPF scriptlets"),
> OPT_STRING(0, "clang-opt", &llvm_param.clang_opt, "clang options",
> diff --git a/tools/perf/perf.h b/tools/perf/perf.h
> index d59dee61b64d..711e009381ec 100644
> --- a/tools/perf/perf.h
> +++ b/tools/perf/perf.h
> @@ -61,6 +61,8 @@ struct record_opts {
> bool record_switch_events;
> bool all_kernel;
> bool all_user;
> + bool kernel_callchains;
> + bool user_callchains;
> bool tail_synthesize;
> bool overwrite;
> bool ignore_missing_thread;
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index a6f572a40deb..a606b2833e27 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -680,6 +680,10 @@ static void __perf_evsel__config_callchain(struct perf_evsel *evsel,
>
> attr->sample_max_stack = param->max_stack;
>
> + if (opts->kernel_callchains)
> + attr->exclude_callchain_user = 1;
> + if (opts->user_callchains)
> + attr->exclude_callchain_kernel = 1;
> if (param->record_mode == CALLCHAIN_LBR) {
> if (!opts->branch_stack) {
> if (attr->exclude_user) {
> --
> 2.14.1
>