kernel_optimize_test/tools/perf/perf.h
Arnaldo Carvalho de Melo b09c2364a4 perf record: Throttle user defined frequencies to the maximum allowed
# perf record -F 200000 sleep 1
  warning: Maximum frequency rate (15,000 Hz) exceeded, throttling from 200,000 Hz to 15,000 Hz.
           The limit can be raised via /proc/sys/kernel/perf_event_max_sample_rate.
           The kernel will lower it when perf's interrupts take too long.
	   Use --strict-freq to disable this throttling, refusing to record.
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.019 MB perf.data (15 samples) ]
  # perf evlist -v
  cycles:ppp: size: 112, { sample_period, sample_freq }: 15000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1

For those wanting that it fails if the desired frequency can't be used:

  # perf record --strict-freq -F 200000 sleep 1
  error: Maximum frequency rate (15,000 Hz) exceeded.
         Please use -F freq option with a lower value or consider
         tweaking /proc/sys/kernel/perf_event_max_sample_rate.
  #

Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-oyebruc44nlja499nqkr1nzn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-03-05 09:58:44 -03:00

89 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PERF_PERF_H
#define _PERF_PERF_H
#include <time.h>
#include <stdbool.h>
#include <linux/types.h>
#include <linux/perf_event.h>
extern bool test_attr__enabled;
void test_attr__ready(void);
void test_attr__init(void);
void test_attr__open(struct perf_event_attr *attr, pid_t pid, int cpu,
int fd, int group_fd, unsigned long flags);
#define HAVE_ATTR_TEST
#include "perf-sys.h"
static inline unsigned long long rdclock(void)
{
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * 1000000000ULL + ts.tv_nsec;
}
#define MAX_NR_CPUS 1024
extern const char *input_name;
extern bool perf_host, perf_guest;
extern const char perf_version_string[];
void pthread__unblock_sigwinch(void);
#include "util/target.h"
struct record_opts {
struct target target;
bool group;
bool inherit_stat;
bool no_buffering;
bool no_inherit;
bool no_inherit_set;
bool no_samples;
bool raw_samples;
bool sample_address;
bool sample_phys_addr;
bool sample_weight;
bool sample_time;
bool sample_time_set;
bool sample_cpu;
bool period;
bool period_set;
bool running_time;
bool full_auxtrace;
bool auxtrace_snapshot_mode;
bool record_namespaces;
bool record_switch_events;
bool all_kernel;
bool all_user;
bool tail_synthesize;
bool overwrite;
bool ignore_missing_thread;
bool strict_freq;
unsigned int freq;
unsigned int mmap_pages;
unsigned int auxtrace_mmap_pages;
unsigned int user_freq;
u64 branch_stack;
u64 sample_intr_regs;
u64 sample_user_regs;
u64 default_interval;
u64 user_interval;
size_t auxtrace_snapshot_size;
const char *auxtrace_snapshot_opts;
bool sample_transaction;
unsigned initial_delay;
bool use_clockid;
clockid_t clockid;
unsigned int proc_map_timeout;
};
struct option;
extern const char * const *record_usage;
extern struct option *record_options;
int record__parse_freq(const struct option *opt, const char *str, int unset);
#endif