Commit ef60b8f5 authored by Namhyung Kim's avatar Namhyung Kim Committed by Arnaldo Carvalho de Melo
Browse files

perf trace: Support --summary-mode=cgroup 



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: default avatarNamhyung Kim <namhyung@kernel.org>
Tested-by: default avatarArnaldo 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: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 39922dc5

tools/perf/Documentation/perf-trace.txt

+2 −1
Original line number Diff line number Diff line
@@ -152,7 +152,8 @@ the thread executes on the designated CPUs. Default is to monitor all CPUs. 


--summary-mode=mode::

	To be used with -s or -S, to select how to show summary.  By default it'll

	show the syscall summary by thread.  Possible values are: thread, total.

	show the syscall summary by thread.  Possible values are: thread, total,

	cgroup.



--tool_stats::

	Show tool stats such as number of times fd->pathname was discovered thru

tools/perf/builtin-trace.c

+9 −1
Original line number Diff line number Diff line
@@ -5302,6 +5302,8 @@ static int trace__parse_summary_mode(const struct option *opt, const char *str, 
		trace->summary_mode = SUMMARY__BY_THREAD;

	} else if (!strcmp(str, "total")) {

		trace->summary_mode = SUMMARY__BY_TOTAL;

	} else if (!strcmp(str, "cgroup")) {

		trace->summary_mode = SUMMARY__BY_CGROUP;

	} else {

		pr_err("Unknown summary mode: %s\n", str);

		return -1;
@@ -5461,7 +5463,7 @@ int cmd_trace(int argc, const char **argv) 
	OPT_BOOLEAN(0, "errno-summary", &trace.errno_summary,

		    "Show errno stats per syscall, use with -s or -S"),

	OPT_CALLBACK(0, "summary-mode", &trace, "mode",

		     "How to show summary: select thread (default) or total",

		     "How to show summary: select thread (default), total or cgroup",

		     trace__parse_summary_mode),

	OPT_CALLBACK_DEFAULT('F', "pf", &trace.trace_pgfaults, "all|maj|min",

		     "Trace pagefaults", parse_pagefaults, "maj"),
@@ -5775,6 +5777,12 @@ int cmd_trace(int argc, const char **argv) 
		symbol_conf.keep_exited_threads = true;

		if (trace.summary_mode == SUMMARY__NONE)

			trace.summary_mode = SUMMARY__BY_THREAD;



		if (!trace.summary_bpf && trace.summary_mode == SUMMARY__BY_CGROUP) {

			pr_err("Error: --summary-mode=cgroup only works with --bpf-summary\n");

			err = -EINVAL;

			goto out;

		}

	}



	if (output_name != NULL) {

tools/perf/util/bpf-trace-summary.c

+117 −6
Original line number Diff line number Diff line
@@ -6,10 +6,12 @@ 


#include "dwarf-regs.h" /* for EM_HOST */

#include "syscalltbl.h"

#include "util/cgroup.h"

#include "util/hashmap.h"

#include "util/trace.h"

#include "util/util.h"

#include <bpf/bpf.h>

#include <linux/rbtree.h>

#include <linux/time64.h>

#include <tools/libc_compat.h> /* reallocarray */
@@ -18,6 +20,7 @@ 




static struct syscall_summary_bpf *skel;

static struct rb_root cgroups = RB_ROOT;



int trace_prepare_bpf_summary(enum trace_summary_mode mode)

{
@@ -29,9 +32,14 @@ int trace_prepare_bpf_summary(enum trace_summary_mode mode) 


	if (mode == SUMMARY__BY_THREAD)

		skel->rodata->aggr_mode = SYSCALL_AGGR_THREAD;

	else if (mode == SUMMARY__BY_CGROUP)

		skel->rodata->aggr_mode = SYSCALL_AGGR_CGROUP;

	else

		skel->rodata->aggr_mode = SYSCALL_AGGR_CPU;



	if (cgroup_is_v2("perf_event") > 0)

		skel->rodata->use_cgroup_v2 = 1;



	if (syscall_summary_bpf__load(skel) < 0) {

		fprintf(stderr, "failed to load syscall summary bpf skeleton\n");

		return -1;
@@ -42,6 +50,9 @@ int trace_prepare_bpf_summary(enum trace_summary_mode mode) 
		return -1;

	}



	if (mode == SUMMARY__BY_CGROUP)

		read_all_cgroups(&cgroups);



	return 0;

}
@@ -88,9 +99,13 @@ static double rel_stddev(struct syscall_stats *stat) 
 * per-cpu analysis so it's keyed by the syscall number to combine stats

 * from different CPUs.  And syscall_data always has a syscall_node so

 * it can effectively work as flat hierarchy.

 *

 * For per-cgroup stats, it uses two-level data structure like thread

 * syscall_data is keyed by CGROUP and has an array of node which

 * represents each syscall for the cgroup.

 */

struct syscall_data {

	int key; /* tid if AGGR_THREAD, syscall-nr if AGGR_CPU */

	u64 key; /* tid if AGGR_THREAD, syscall-nr if AGGR_CPU, cgroup if AGGR_CGROUP */

	int nr_events;

	int nr_nodes;

	u64 total_time;
@@ -191,7 +206,7 @@ static int print_thread_stat(struct syscall_data *data, FILE *fp) 


	qsort(data->nodes, data->nr_nodes, sizeof(*data->nodes), nodecmp);



	printed += fprintf(fp, " thread (%d), ", data->key);

	printed += fprintf(fp, " thread (%d), ", (int)data->key);

	printed += fprintf(fp, "%d events\n\n", data->nr_events);



	printed += fprintf(fp, "   syscall            calls  errors  total       min       avg       max       stddev\n");
@@ -283,6 +298,75 @@ static int print_total_stats(struct syscall_data **data, int nr_data, FILE *fp) 
	return printed;

}



static int update_cgroup_stats(struct hashmap *hash, struct syscall_key *map_key,

			       struct syscall_stats *map_data)

{

	struct syscall_data *data;

	struct syscall_node *nodes;



	if (!hashmap__find(hash, map_key->cgroup, &data)) {

		data = zalloc(sizeof(*data));

		if (data == NULL)

			return -ENOMEM;



		data->key = map_key->cgroup;

		if (hashmap__add(hash, data->key, data) < 0) {

			free(data);

			return -ENOMEM;

		}

	}



	/* update thread total stats */

	data->nr_events += map_data->count;

	data->total_time += map_data->total_time;



	nodes = reallocarray(data->nodes, data->nr_nodes + 1, sizeof(*nodes));

	if (nodes == NULL)

		return -ENOMEM;



	data->nodes = nodes;

	nodes = &data->nodes[data->nr_nodes++];

	nodes->syscall_nr = map_key->nr;



	/* each thread has an entry for each syscall, just use the stat */

	memcpy(&nodes->stats, map_data, sizeof(*map_data));

	return 0;

}



static int print_cgroup_stat(struct syscall_data *data, FILE *fp)

{

	int printed = 0;

	struct cgroup *cgrp = __cgroup__find(&cgroups, data->key);



	qsort(data->nodes, data->nr_nodes, sizeof(*data->nodes), nodecmp);



	if (cgrp)

		printed += fprintf(fp, " cgroup %s,", cgrp->name);

	else

		printed += fprintf(fp, " cgroup id:%lu,", (unsigned long)data->key);



	printed += fprintf(fp, " %d events\n\n", data->nr_events);



	printed += fprintf(fp, "   syscall            calls  errors  total       min       avg       max       stddev\n");

	printed += fprintf(fp, "                                     (msec)    (msec)    (msec)    (msec)        (%%)\n");

	printed += fprintf(fp, "   --------------- --------  ------ -------- --------- --------- ---------     ------\n");



	printed += print_common_stats(data, fp);

	printed += fprintf(fp, "\n\n");



	return printed;

}



static int print_cgroup_stats(struct syscall_data **data, int nr_data, FILE *fp)

{

	int printed = 0;



	for (int i = 0; i < nr_data; i++)

		printed += print_cgroup_stat(data[i], fp);



	return printed;

}



int trace_print_bpf_summary(FILE *fp)

{

	struct bpf_map *map = skel->maps.syscall_stats_map;
@@ -305,10 +389,19 @@ int trace_print_bpf_summary(FILE *fp) 
		struct syscall_stats stat;



		if (!bpf_map__lookup_elem(map, &key, sizeof(key), &stat, sizeof(stat), 0)) {

			if (skel->rodata->aggr_mode == SYSCALL_AGGR_THREAD)

			switch (skel->rodata->aggr_mode) {

			case SYSCALL_AGGR_THREAD:

				update_thread_stats(&schash, &key, &stat);

			else

				break;

			case SYSCALL_AGGR_CPU:

				update_total_stats(&schash, &key, &stat);

				break;

			case SYSCALL_AGGR_CGROUP:

				update_cgroup_stats(&schash, &key, &stat);

				break;

			default:

				break;

			}

		}



		prev_key = &key;
@@ -325,10 +418,19 @@ int trace_print_bpf_summary(FILE *fp) 


	qsort(data, nr_data, sizeof(*data), datacmp);



	if (skel->rodata->aggr_mode == SYSCALL_AGGR_THREAD)

	switch (skel->rodata->aggr_mode) {

	case SYSCALL_AGGR_THREAD:

		printed += print_thread_stats(data, nr_data, fp);

	else

		break;

	case SYSCALL_AGGR_CPU:

		printed += print_total_stats(data, nr_data, fp);

		break;

	case SYSCALL_AGGR_CGROUP:

		printed += print_cgroup_stats(data, nr_data, fp);

		break;

	default:

		break;

	}



	for (i = 0; i < nr_data && data; i++) {

		free(data[i]->nodes);
@@ -343,5 +445,14 @@ int trace_print_bpf_summary(FILE *fp) 


void trace_cleanup_bpf_summary(void)

{

	if (!RB_EMPTY_ROOT(&cgroups)) {

		struct cgroup *cgrp, *tmp;



		rbtree_postorder_for_each_entry_safe(cgrp, tmp, &cgroups, node)

			cgroup__put(cgrp);



		cgroups = RB_ROOT;

	}



	syscall_summary_bpf__destroy(skel);

}

tools/perf/util/bpf_skel/syscall_summary.bpf.c

+39 −4
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 


#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>

#include <bpf/bpf_core_read.h>



/* This is to calculate a delta between sys-enter and sys-exit for each thread */

struct syscall_trace {
@@ -35,10 +36,41 @@ struct syscall_stats_map { 
int enabled; /* controlled from userspace */



const volatile enum syscall_aggr_mode aggr_mode;

const volatile int use_cgroup_v2;



static void update_stats(int cpu_or_tid, int nr, s64 duration, long ret)

int perf_subsys_id = -1;



static inline __u64 get_current_cgroup_id(void)

{

	struct task_struct *task;

	struct cgroup *cgrp;



	if (use_cgroup_v2)

		return bpf_get_current_cgroup_id();



	task = bpf_get_current_task_btf();



	if (perf_subsys_id == -1) {

#if __has_builtin(__builtin_preserve_enum_value)

		perf_subsys_id = bpf_core_enum_value(enum cgroup_subsys_id,

						     perf_event_cgrp_id);

#else

		perf_subsys_id = perf_event_cgrp_id;

#endif

	}



	cgrp = BPF_CORE_READ(task, cgroups, subsys[perf_subsys_id], cgroup);

	return BPF_CORE_READ(cgrp, kn, id);

}



static void update_stats(int cpu_or_tid, u64 cgroup_id, int nr, s64 duration,

			 long ret)

{

	struct syscall_key key = { .cpu_or_tid = cpu_or_tid, .nr = nr, };

	struct syscall_key key = {

		.cpu_or_tid = cpu_or_tid,

		.cgroup = cgroup_id,

		.nr = nr,

	};

	struct syscall_stats *stats;



	stats = bpf_map_lookup_elem(&syscall_stats_map, &key);
@@ -90,7 +122,8 @@ SEC("tp_btf/sys_exit") 
int sys_exit(u64 *ctx)

{

	int tid;

	int key;

	int key = 0;

	u64 cgroup = 0;

	long ret = ctx[1]; /* return value of the syscall */

	struct syscall_trace *st;

	s64 delta;
@@ -105,11 +138,13 @@ int sys_exit(u64 *ctx) 


	if (aggr_mode == SYSCALL_AGGR_THREAD)

		key = tid;

	else if (aggr_mode == SYSCALL_AGGR_CGROUP)

		cgroup = get_current_cgroup_id();

	else

		key = bpf_get_smp_processor_id();



	delta = bpf_ktime_get_ns() - st->timestamp;

	update_stats(key, st->nr, delta, ret);

	update_stats(key, cgroup, st->nr, delta, ret);



	bpf_map_delete_elem(&syscall_trace_map, &tid);

	return 0;

tools/perf/util/bpf_skel/syscall_summary.h

+2 −0
Original line number Diff line number Diff line
@@ -6,9 +6,11 @@ 
enum syscall_aggr_mode {

	SYSCALL_AGGR_THREAD,

	SYSCALL_AGGR_CPU,

	SYSCALL_AGGR_CGROUP,

};



struct syscall_key {

	u64 cgroup;

	int cpu_or_tid;

	int nr;

};