path: root/tools/perf/builtin-diff.c

// SPDX-License-Identifier: GPL-2.0
/*
 * builtin-diff.c
 *
 * Builtin diff command: Analyze two perf.data input files, look up and read
 * DSOs and symbol information, sort them and produce a diff.
 */
#include "builtin.h"

#include "util/debug.h"
#include "util/event.h"
#include "util/hist.h"
#include "util/evsel.h"
#include "util/evlist.h"
#include "util/session.h"
#include "util/tool.h"
#include "util/sort.h"
#include "util/symbol.h"
#include "util/util.h"
#include "util/data.h"
#include "util/config.h"
#include "util/time-utils.h"

#include <errno.h>
#include <inttypes.h>
#include <stdlib.h>
#include <math.h>

struct perf_diff {
	struct perf_tool		 tool;
	const char			*time_str;
	struct perf_time_interval	*ptime_range;
	int				 range_size;
	int				 range_num;
};

/* Diff command specific HPP columns. */
enum {
	PERF_HPP_DIFF__BASELINE,
	PERF_HPP_DIFF__PERIOD,
	PERF_HPP_DIFF__PERIOD_BASELINE,
	PERF_HPP_DIFF__DELTA,
	PERF_HPP_DIFF__RATIO,
	PERF_HPP_DIFF__WEIGHTED_DIFF,
	PERF_HPP_DIFF__FORMULA,
	PERF_HPP_DIFF__DELTA_ABS,

	PERF_HPP_DIFF__MAX_INDEX
};

struct diff_hpp_fmt {
	struct perf_hpp_fmt	 fmt;
	int			 idx;
	char			*header;
	int			 header_width;
};

struct data__file {
	struct perf_session	*session;
	struct perf_data	 data;
	int			 idx;
	struct hists		*hists;
	struct diff_hpp_fmt	 fmt[PERF_HPP_DIFF__MAX_INDEX];
};

static struct data__file *data__files;
static int data__files_cnt;

#define data__for_each_file_start(i, d, s)	\
	for (i = s, d = &data__files[s];	\
	     i < data__files_cnt;		\
	     i++, d = &data__files[i])

#define data__for_each_file(i, d) data__for_each_file_start(i, d, 0)
#define data__for_each_file_new(i, d) data__for_each_file_start(i, d, 1)

static bool force;
static bool show_period;
static bool show_formula;
static bool show_baseline_only;
static unsigned int sort_compute = 1;

static s64 compute_wdiff_w1;
static s64 compute_wdiff_w2;

static const char		*cpu_list;
static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);

enum {
	COMPUTE_DELTA,
	COMPUTE_RATIO,
	COMPUTE_WEIGHTED_DIFF,
	COMPUTE_DELTA_ABS,
	COMPUTE_MAX,
};

const char *compute_names[COMPUTE_MAX] = {
	[COMPUTE_DELTA] = "delta",
	[COMPUTE_DELTA_ABS] = "delta-abs",
	[COMPUTE_RATIO] = "ratio",
	[COMPUTE_WEIGHTED_DIFF] = "wdiff",
};

static int compute = COMPUTE_DELTA_ABS;

static int compute_2_hpp[COMPUTE_MAX] = {
	[COMPUTE_DELTA]		= PERF_HPP_DIFF__DELTA,
	[COMPUTE_DELTA_ABS]	= PERF_HPP_DIFF__DELTA_ABS,
	[COMPUTE_RATIO]		= PERF_HPP_DIFF__RATIO,
	[COMPUTE_WEIGHTED_DIFF]	= PERF_HPP_DIFF__WEIGHTED_DIFF,
};

#define MAX_COL_WIDTH 70

static struct header_column {
	const char *name;
	int width;
} columns[PERF_HPP_DIFF__MAX_INDEX] = {
	[PERF_HPP_DIFF__BASELINE] = {
		.name  = "Baseline",
	},
	[PERF_HPP_DIFF__PERIOD] = {
		.name  = "Period",
		.width = 14,
	},
	[PERF_HPP_DIFF__PERIOD_BASELINE] = {
		.name  = "Base period",
		.width = 14,
	},
	[PERF_HPP_DIFF__DELTA] = {
		.name  = "Delta",
		.width = 7,
	},
	[PERF_HPP_DIFF__DELTA_ABS] = {
		.name  = "Delta Abs",
		.width = 7,
	},
	[PERF_HPP_DIFF__RATIO] = {
		.name  = "Ratio",
		.width = 14,
	},
	[PERF_HPP_DIFF__WEIGHTED_DIFF] = {
		.name  = "Weighted diff",
		.width = 14,
	},
	[PERF_HPP_DIFF__FORMULA] = {
		.name  = "Formula",
		.width = MAX_COL_WIDTH,
	}
};

static int setup_compute_opt_wdiff(char *opt)
{
	char *w1_str = opt;
	char *w2_str;

	int ret = -EINVAL;

	if (!opt)
		goto out;

	w2_str = strchr(opt, ',');
	if (!w2_str)
		goto out;

	*w2_str++ = 0x0;
	if (!*w2_str)
		goto out;

	compute_wdiff_w1 = strtol(w1_str, NULL, 10);
	compute_wdiff_w2 = strtol(w2_str, NULL, 10);

	if (!compute_wdiff_w1 || !compute_wdiff_w2)
		goto out;

	pr_debug("compute wdiff w1(%" PRId64 ") w2(%" PRId64 ")\n",
		  compute_wdiff_w1, compute_wdiff_w2);

	ret = 0;

 out:
	if (ret)
		pr_err("Failed: wrong weight data, use 'wdiff:w1,w2'\n");

	return ret;
}

static int setup_compute_opt(char *opt)
{
	if (compute == COMPUTE_WEIGHTED_DIFF)
		return setup_compute_opt_wdiff(opt);

	if (opt) {
		pr_err("Failed: extra option specified '%s'", opt);
		return -EINVAL;
	}

	return 0;
}

static int setup_compute(const struct option *opt, const char *str,
			 int unset __maybe_unused)
{
	int *cp = (int *) opt->value;
	char *cstr = (char *) str;
	char buf[50];
	unsigned i;
	char *option;

	if (!str) {
		*cp = COMPUTE_DELTA;
		return 0;
	}

	option = strchr(str, ':');
	if (option) {
		unsigned len = option++ - str;

		/*
		 * The str data are not writeable, so we need
		 * to use another buffer.
		 */

		/* No option value is longer. */
		if (len >= sizeof(buf))
			return -EINVAL;

		strncpy(buf, str, len);
		buf[len] = 0x0;
		cstr = buf;
	}

	for (i = 0; i < COMPUTE_MAX; i++)
		if (!strcmp(cstr, compute_names[i])) {
			*cp = i;
			return setup_compute_opt(option);
		}

	pr_err("Failed: '%s' is not computation method "
	       "(use 'delta','ratio' or 'wdiff')\n", str);
	return -EINVAL;
}

static double period_percent(struct hist_entry *he, u64 period)
{
	u64 total = hists__total_period(he->hists);

	return (period * 100.0) / total;
}

static double compute_delta(struct hist_entry *he, struct hist_entry *pair)
{
	double old_percent = period_percent(he, he->stat.period);
	double new_percent = period_percent(pair, pair->stat.period);

	pair->diff.period_ratio_delta = new_percent - old_percent;
	pair->diff.computed = true;
	return pair->diff.period_ratio_delta;
}

static double compute_ratio(struct hist_entry *he, struct hist_entry *pair)
{
	double old_period = he->stat.period ?: 1;
	double new_period = pair->stat.period;

	pair->diff.computed = true;
	pair->diff.period_ratio = new_period / old_period;
	return pair->diff.period_ratio;
}

static s64 compute_wdiff(struct hist_entry *he, struct hist_entry *pair)
{
	u64 old_period = he->stat.period;
	u64 new_period = pair->stat.period;

	pair->diff.computed = true;
	pair->diff.wdiff = new_period * compute_wdiff_w2 -
			   old_period * compute_wdiff_w1;

	return pair->diff.wdiff;
}

static int formula_delta(struct hist_entry *he, struct hist_entry *pair,
			 char *buf, size_t size)
{
	u64 he_total = he->hists->stats.total_period;
	u64 pair_total = pair->hists->stats.total_period;

	if (symbol_conf.filter_relative) {
		he_total = he->hists->stats.total_non_filtered_period;
		pair_total = pair->hists->stats.total_non_filtered_period;
	}
	return scnprintf(buf, size,
			 "(%" PRIu64 " * 100 / %" PRIu64 ") - "
			 "(%" PRIu64 " * 100 / %" PRIu64 ")",
			 pair->stat.period, pair_total,
			 he->stat.period, he_total);
}

static int formula_ratio(struct hist_entry *he, struct hist_entry *pair,
			 char *buf, size_t size)
{
	double old_period = he->stat.period;
	double new_period = pair->stat.period;

	return scnprintf(buf, size, "%.0F / %.0F", new_period, old_period);
}

static int formula_wdiff(struct hist_entry *he, struct hist_entry *pair,
			 char *buf, size_t size)
{
	u64 old_period = he->stat.period;
	u64 new_period = pair->stat.period;

	return scnprintf(buf, size,
		  "(%" PRIu64 " * " "%" PRId64 ") - (%" PRIu64 " * " "%" PRId64 ")",
		  new_period, compute_wdiff_w2, old_period, compute_wdiff_w1);
}

static int formula_fprintf(struct hist_entry *he, struct hist_entry *pair,
			   char *buf, size_t size)
{
	switch (compute) {
	case COMPUTE_DELTA:
	case COMPUTE_DELTA_ABS:
		return formula_delta(he, pair, buf, size);
	case COMPUTE_RATIO:
		return formula_ratio(he, pair, buf, size);
	case COMPUTE_WEIGHTED_DIFF:
		return formula_wdiff(he, pair, buf, size);
	default:
		BUG_ON(1);
	}

	return -1;
}

static int diff__process_sample_event(struct perf_tool *tool,
				      union perf_event *event,
				      struct perf_sample *sample,
				      struct perf_evsel *evsel,
				      struct machine *machine)
{
	struct perf_diff *pdiff = container_of(tool, struct perf_diff, tool);
	struct addr_location al;
	struct hists *hists = evsel__hists(evsel);
	int ret = -1;

	if (perf_time__ranges_skip_sample(pdiff->ptime_range, pdiff->range_num,
					  sample->time)) {
		return 0;
	}

	if (machine__resolve(machine, &al, sample) < 0) {
		pr_warning("problem processing %d event, skipping it.\n",
			   event->header.type);
		return -1;
	}

	if (cpu_list && !test_bit(sample->cpu, cpu_bitmap)) {
		ret = 0;
		goto out_put;
	}