Re: [PATCH v4 05/15] perf tools report: Parse time quantum

[Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>]

Em Tue, Mar 05, 2019 at 06:47:48AM -0800, Andi Kleen escreveu:
> From: Andi Kleen <ak@linux.intel.com>
> 
> Many workloads change over time. perf report currently aggregates
> the whole time range reported in perf.data.
> 
> This patch adds an option for a time quantum to quantisize the
> perf.data over time.
> 
> This just adds the option, will be used in follow on patches
> for a time sort key.
> 
> Signed-off-by: Andi Kleen <ak@linux.intel.com>
> 
> ---
> v2:
> Move time_quantum to symbol_conf. check for zero time quantum
> v3:
> Document s unit
> ---
>  tools/perf/Documentation/perf-report.txt |  4 +++
>  tools/perf/builtin-report.c              | 41 ++++++++++++++++++++++++
>  tools/perf/util/symbol.c                 |  1 +
>  tools/perf/util/symbol_conf.h            |  1 +
>  4 files changed, 47 insertions(+)
> 
> diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
> index 51dbc519dbce..9ec1702bccdd 100644
> --- a/tools/perf/Documentation/perf-report.txt
> +++ b/tools/perf/Documentation/perf-report.txt
> @@ -497,6 +497,10 @@ include::itrace.txt[]
>  	The period/hits keywords set the base the percentage is computed
>  	on - the samples period or the number of samples (hits).
>  
> +--time-quantum::
> +	Configure time quantum for time sort key. Default 100ms.
> +	Accepts s, us, ms, ns units.
> +
>  include::callchain-overhead-calculation.txt[]
>  
>  SEE ALSO
> diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
> index 09180e559ad6..c19952072a3a 100644
> --- a/tools/perf/builtin-report.c
> +++ b/tools/perf/builtin-report.c
> @@ -47,6 +47,7 @@
>  #include <errno.h>
>  #include <inttypes.h>
>  #include <regex.h>
> +#include "sane_ctype.h"
>  #include <signal.h>
>  #include <linux/bitmap.h>
>  #include <linux/stringify.h>
> @@ -926,6 +927,43 @@ report_parse_callchain_opt(const struct option *opt, const char *arg, int unset)
>  	return parse_callchain_report_opt(arg);
>  }
>  
> +static int
> +parse_time_quantum(const struct option *opt, const char *arg,
> +		   int unset __maybe_unused)
> +{
> +	unsigned long *time_q = opt->value;
> +	char *end;
> +
> +	*time_q = strtoul(arg, &end, 0);
> +	if (end == arg)
> +		goto parse_err;
> +	if (*time_q == 0) {
> +		pr_err("time quantum cannot be 0");
> +		return -1;
> +	}
> +	while (isspace(*end))
> +		end++;
> +	if (*end == 0)
> +		return 0;

We have tools/include/linux/time64.h, just like the kernel, so please
use:

#include <linux/time64.h>

> +	if (!strcmp(end, "s")) {
> +		*time_q *= 1000000000;
                           NSEC_PER_SEC;


> +		return 0;
> +	}
> +	if (!strcmp(end, "ms")) {
> +		*time_q *= 1000000;
                           NSEC_PER_MSEC;
> +		return 0;
> +	}
> +	if (!strcmp(end, "us")) {
> +		*time_q *= 1000;
                           NSEC_PER_USEC;

one more note below

> +		return 0;
> +	}
> +	if (!strcmp(end, "ns"))
> +		return 0;
> +parse_err:
> +	pr_err("Cannot parse time quantum `%s'\n", arg);
> +	return -1;
> +}
> +
>  int
>  report_parse_ignore_callees_opt(const struct option *opt __maybe_unused,
>  				const char *arg, int unset __maybe_unused)
> @@ -1148,6 +1186,9 @@ int cmd_report(int argc, const char **argv)
>  		     "Set percent type local/global-period/hits",
>  		     annotate_parse_percent_type),
>  	OPT_BOOLEAN(0, "ns", &symbol_conf.nanosecs, "Show times in nanosecs"),
> +	OPT_CALLBACK(0, "time-quantum", &symbol_conf.time_quantum, "time (ms|us|ns|s)",
> +		     "Set time quantum for time sort key (default 100ms)",
> +		     parse_time_quantum),
>  	OPT_END()
>  	};
>  	struct perf_data data = {
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index eb873ea1c405..0f80743a1c25 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -45,6 +45,7 @@ struct symbol_conf symbol_conf = {
>  	.demangle		= true,
>  	.demangle_kernel	= false,
>  	.cumulate_callchain	= true,
> +	.time_quantum		= 100000000, /* 100ms */

                                  100 * NSEC_PER_MSEC;

>  	.show_hist_headers	= true,
>  	.symfs			= "",
>  	.event_group		= true,
> diff --git a/tools/perf/util/symbol_conf.h b/tools/perf/util/symbol_conf.h
> index 095a297c8b47..a5684a71b78e 100644
> --- a/tools/perf/util/symbol_conf.h
> +++ b/tools/perf/util/symbol_conf.h
> @@ -56,6 +56,7 @@ struct symbol_conf {
>  			*sym_list_str,
>  			*col_width_list_str,
>  			*bt_stop_list_str;
> +	unsigned long	time_quantum;
>         struct strlist	*dso_list,
>  			*comm_list,
>  			*sym_list,
> -- 
> 2.20.1

-- 

- Arnaldo