perf report: Support time sort key

Add a time sort key to perf report to display samples for different time
quantums separately. This allows easier analysis of workloads that
change over time, and also will allow looking at the context of samples.

% perf record ...
% perf report --sort time,overhead,symbol --time-quantum 1ms --stdio
...
     0.67%  277061.87300  [.] _dl_start
     0.50%  277061.87300  [.] f1
     0.50%  277061.87300  [.] f2
     0.33%  277061.87300  [.] main
     0.29%  277061.87300  [.] _dl_lookup_symbol_x
     0.29%  277061.87300  [.] dl_main
     0.29%  277061.87300  [.] do_lookup_x
     0.17%  277061.87300  [.] _dl_debug_initialize
     0.17%  277061.87300  [.] _dl_init_paths
     0.08%  277061.87300  [.] check_match
     0.04%  277061.87300  [.] _dl_count_modids
     1.33%  277061.87400  [.] f1
     1.33%  277061.87400  [.] f2
     1.33%  277061.87400  [.] main
     1.17%  277061.87500  [.] main
     1.08%  277061.87500  [.] f1
     1.08%  277061.87500  [.] f2
     1.00%  277061.87600  [.] main
     0.83%  277061.87600  [.] f1
     0.83%  277061.87600  [.] f2
     1.00%  277061.87700  [.] main

Committer notes:

Rename 'time' argument to hist_time() to htime to overcome this in older
distros:

  cc1: warnings being treated as errors
  util/hist.c: In function 'hist_time':
  util/hist.c:251: error: declaration of 'time' shadows a global declaration
  /usr/include/time.h:186: error: shadowed declaration is here

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20190311144502.15423-4-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Documentation/perf-report.txt

@@ -105,6 +105,8 @@ OPTIONS
 	guest machine
 	- sample: Number of sample
 	- period: Raw number of event count of sample
+	- time: Separate the samples by time stamp with the resolution specified by
+	--time-quantum (default 100ms). Specify with overhead and before it.
 
 	By default, comm, dso and symbol keys are used.
 	(i.e. --sort comm,dso,symbol)

tools/perf/util/hist.c

@@ -19,6 +19,7 @@
 #include <math.h>
 #include <inttypes.h>
 #include <sys/param.h>
+#include <linux/time64.h>
 
 static bool hists__filter_entry_by_dso(struct hists *hists,
 				       struct hist_entry *he);
@@ -192,6 +193,7 @@ void hists__calc_col_len(struct hists *hists, struct hist_entry *h)
 	hists__new_col_len(hists, HISTC_MEM_LVL, 21 + 3);
 	hists__new_col_len(hists, HISTC_LOCAL_WEIGHT, 12);
 	hists__new_col_len(hists, HISTC_GLOBAL_WEIGHT, 12);
+	hists__new_col_len(hists, HISTC_TIME, 12);
 
 	if (h->srcline) {
 		len = MAX(strlen(h->srcline), strlen(sort_srcline.se_header));
@@ -246,6 +248,14 @@ static void he_stat__add_cpumode_period(struct he_stat *he_stat,
 	}
 }
 
+static long hist_time(unsigned long htime)
+{
+	unsigned long time_quantum = symbol_conf.time_quantum;
+	if (time_quantum)
+		return (htime / time_quantum) * time_quantum;
+	return htime;
+}
+
 static void he_stat__add_period(struct he_stat *he_stat, u64 period,
 				u64 weight)
 {
@@ -635,6 +645,7 @@ __hists__add_entry(struct hists *hists,
 		.raw_data = sample->raw_data,
 		.raw_size = sample->raw_size,
 		.ops = ops,
+		.time = hist_time(sample->time),
 	}, *he = hists__findnew_entry(hists, &entry, al, sample_self);
 
 	if (!hists->has_callchains && he && he->callchain_size != 0)

tools/perf/util/hist.h

@@ -31,6 +31,7 @@ enum hist_filter {
 
 enum hist_column {
 	HISTC_SYMBOL,
+	HISTC_TIME,
 	HISTC_DSO,
 	HISTC_THREAD,
 	HISTC_COMM,

tools/perf/util/sort.c

@@ -3,6 +3,7 @@
 #include <inttypes.h>
 #include <regex.h>
 #include <linux/mman.h>
+#include <linux/time64.h>
 #include "sort.h"
 #include "hist.h"
 #include "comm.h"
@@ -15,6 +16,7 @@
 #include <traceevent/event-parse.h>
 #include "mem-events.h"
 #include "annotate.h"
+#include "time-utils.h"
 #include <linux/kernel.h>
 
 regex_t		parent_regex;
@@ -654,6 +656,42 @@ struct sort_entry sort_socket = {
 	.se_width_idx	= HISTC_SOCKET,
 };
 
+/* --sort time */
+
+static int64_t
+sort__time_cmp(struct hist_entry *left, struct hist_entry *right)
+{
+	return right->time - left->time;
+}
+
+static int hist_entry__time_snprintf(struct hist_entry *he, char *bf,
+				    size_t size, unsigned int width)
+{
+	unsigned long secs;
+	unsigned long long nsecs;
+	char he_time[32];
+
+	nsecs = he->time;
+	secs = nsecs / NSEC_PER_SEC;
+	nsecs -= secs * NSEC_PER_SEC;
+
+	if (symbol_conf.nanosecs)
+		snprintf(he_time, sizeof he_time, "%5lu.%09llu: ",
+			 secs, nsecs);
+	else
+		timestamp__scnprintf_usec(he->time, he_time,
+					  sizeof(he_time));
+
+	return repsep_snprintf(bf, size, "%-.*s", width, he_time);
+}
+
+struct sort_entry sort_time = {
+	.se_header      = "Time",
+	.se_cmp	        = sort__time_cmp,
+	.se_snprintf    = hist_entry__time_snprintf,
+	.se_width_idx	= HISTC_TIME,
+};
+
 /* --sort trace */
 
 static char *get_trace_output(struct hist_entry *he)
@@ -1634,6 +1672,7 @@ static struct sort_dimension common_sort_dimensions[] = {
 	DIM(SORT_DSO_SIZE, "dso_size", sort_dso_size),
 	DIM(SORT_CGROUP_ID, "cgroup_id", sort_cgroup_id),
 	DIM(SORT_SYM_IPC_NULL, "ipc_null", sort_sym_ipc_null),
+	DIM(SORT_TIME, "time", sort_time),
 };
 
 #undef DIM

tools/perf/util/sort.h

@@ -135,6 +135,7 @@ struct hist_entry {
 	char			*srcfile;
 	struct symbol		*parent;
 	struct branch_info	*branch_info;
+	long			time;
 	struct hists		*hists;
 	struct mem_info		*mem_info;
 	void			*raw_data;
@@ -231,6 +232,7 @@ enum sort_type {
 	SORT_DSO_SIZE,
 	SORT_CGROUP_ID,
 	SORT_SYM_IPC_NULL,
+	SORT_TIME,
 
 	/* branch stack specific sort keys */
 	__SORT_BRANCH_STACK,