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Viewing changes to tools/perf/util/record.c

  • Committer: Package Import Robot
  • Author(s): Ben Hutchings
  • Date: 2014-02-02 16:57:49 UTC
  • mfrom: (1.1.10) (0.1.21 sid)
  • Revision ID: package-import@ubuntu.com-20140202165749-tw94o9t1t0a8txk6
Tags: 3.13-1~exp2
Merge changes from sid up to 3.12.6-3

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Lines of Context:
tools/perf/util/record.c
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#include "evsel.h"
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#include "cpumap.h"
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#include "parse-events.h"
 
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#include "fs.h"
 
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#include "util.h"
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typedef void (*setup_probe_fn_t)(struct perf_evsel *evsel);
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        perf_evlist__set_id_pos(evlist);
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}
 
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static int get_max_rate(unsigned int *rate)
 
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{
 
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        char path[PATH_MAX];
 
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        const char *procfs = procfs__mountpoint();
 
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        if (!procfs)
 
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                return -1;
 
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        snprintf(path, PATH_MAX,
 
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                 "%s/sys/kernel/perf_event_max_sample_rate", procfs);
 
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        return filename__read_int(path, (int *) rate);
 
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}
 
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static int perf_record_opts__config_freq(struct perf_record_opts *opts)
 
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{
 
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        bool user_freq = opts->user_freq != UINT_MAX;
 
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        unsigned int max_rate;
 
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        if (opts->user_interval != ULLONG_MAX)
 
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                opts->default_interval = opts->user_interval;
 
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        if (user_freq)
 
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                opts->freq = opts->user_freq;
 
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        /*
 
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         * User specified count overrides default frequency.
 
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         */
 
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        if (opts->default_interval)
 
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                opts->freq = 0;
 
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        else if (opts->freq) {
 
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                opts->default_interval = opts->freq;
 
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        } else {
 
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                pr_err("frequency and count are zero, aborting\n");
 
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                return -1;
 
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        }
 
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        if (get_max_rate(&max_rate))
 
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                return 0;
 
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        /*
 
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         * User specified frequency is over current maximum.
 
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         */
 
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        if (user_freq && (max_rate < opts->freq)) {
 
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                pr_err("Maximum frequency rate (%u) reached.\n"
 
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                   "Please use -F freq option with lower value or consider\n"
 
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                   "tweaking /proc/sys/kernel/perf_event_max_sample_rate.\n",
 
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                   max_rate);
 
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                return -1;
 
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        }
 
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        /*
 
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         * Default frequency is over current maximum.
 
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         */
 
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        if (max_rate < opts->freq) {
 
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                pr_warning("Lowering default frequency rate to %u.\n"
 
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                           "Please consider tweaking "
 
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                           "/proc/sys/kernel/perf_event_max_sample_rate.\n",
 
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                           max_rate);
 
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                opts->freq = max_rate;
 
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        }
 
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        return 0;
 
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}
 
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int perf_record_opts__config(struct perf_record_opts *opts)
 
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{
 
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        return perf_record_opts__config_freq(opts);
 
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}