Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
tools/rtla: Consolidate nr_cpus usage across all tools
sysconf(_SC_NPROCESSORS_CONF) (via get_nprocs_conf) reflects
cpu_possible_mask, which is fixed at boot time, so querying it
repeatedly is unnecessary.
Replace multiple calls to sysconf(_SC_NPROCESSORS_CONF) with a single
global nr_cpus variable initialized once at startup.
`#pragma once` in timerlat_u.h is needed for pre-C23 compilers to avoid
redefinition errors.
Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
Link: https://lore.kernel.org/r/20260306194953.2511960-2-costa.shul@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
authored by
Costa Shulyupin
and committed by
Tomas Glozar
115b06a0
e4be7e96
+29
-60
+5
-2
tools/tracing/rtla/src/common.c
+5
-2
tools/tracing/rtla/src/common.c
···
5
5
#include <signal.h>
6
6
#include <stdlib.h>
7
7
#include <string.h>
8
-
#include <unistd.h>
9
8
#include <getopt.h>
9
+
#include <sys/sysinfo.h>
10
+
10
11
#include "common.h"
11
12
12
13
struct trace_instance *trace_inst;
13
14
volatile int stop_tracing;
15
+
int nr_cpus;
14
16
15
17
static void stop_trace(int sig)
16
18
{
···
167
165
}
168
166
169
167
if (!params->cpus) {
170
-
for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++)
168
+
for (i = 0; i < nr_cpus; i++)
171
169
CPU_SET(i, ¶ms->monitored_cpus);
172
170
}
173
171
···
215
213
bool stopped;
216
214
int retval;
217
215
216
+
nr_cpus = get_nprocs_conf();
218
217
params = ops->parse_args(argc, argv);
219
218
if (!params)
220
219
exit(1);
+2
tools/tracing/rtla/src/common.h
+2
tools/tracing/rtla/src/common.h
-3
tools/tracing/rtla/src/osnoise_hist.c
-3
tools/tracing/rtla/src/osnoise_hist.c
-7
tools/tracing/rtla/src/osnoise_top.c
-7
tools/tracing/rtla/src/osnoise_top.c
···
232
232
{
233
233
struct osnoise_params *params = to_osnoise_params(top->params);
234
234
struct trace_instance *trace = &top->trace;
235
-
static int nr_cpus = -1;
236
235
int i;
237
-
238
-
if (nr_cpus == -1)
239
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
240
236
241
237
if (!params->common.quiet)
242
238
clear_terminal(trace->seq);
···
490
494
struct osnoise_tool *osnoise_init_top(struct common_params *params)
491
495
{
492
496
struct osnoise_tool *tool;
493
-
int nr_cpus;
494
-
495
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
496
497
497
498
tool = osnoise_init_tool("osnoise_top");
498
499
if (!tool)
+1
-4
tools/tracing/rtla/src/timerlat.c
+1
-4
tools/tracing/rtla/src/timerlat.c
···
99
99
int timerlat_enable(struct osnoise_tool *tool)
100
100
{
101
101
struct timerlat_params *params = to_timerlat_params(tool->params);
102
-
int retval, nr_cpus, i;
102
+
int retval, i;
103
103
104
104
if (params->dma_latency >= 0) {
105
105
dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
···
114
114
err_msg("rtla built without libcpupower, --deepest-idle-state is not supported\n");
115
115
return -1;
116
116
}
117
-
118
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
119
117
120
118
for_each_monitored_cpu(i, nr_cpus, ¶ms->common) {
121
119
if (save_cpu_idle_disable_state(i) < 0) {
···
212
214
void timerlat_free(struct osnoise_tool *tool)
213
215
{
214
216
struct timerlat_params *params = to_timerlat_params(tool->params);
215
-
int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
216
217
int i;
217
218
218
219
timerlat_aa_destroy();
-1
tools/tracing/rtla/src/timerlat_aa.c
-1
tools/tracing/rtla/src/timerlat_aa.c
-3
tools/tracing/rtla/src/timerlat_hist.c
-3
tools/tracing/rtla/src/timerlat_hist.c
-7
tools/tracing/rtla/src/timerlat_top.c
-7
tools/tracing/rtla/src/timerlat_top.c
···
442
442
struct timerlat_params *params = to_timerlat_params(top->params);
443
443
struct trace_instance *trace = &top->trace;
444
444
struct timerlat_top_cpu summary;
445
-
static int nr_cpus = -1;
446
445
int i;
447
446
448
447
if (params->common.aa_only)
449
448
return;
450
-
451
-
if (nr_cpus == -1)
452
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
453
449
454
450
if (!params->common.quiet)
455
451
clear_terminal(trace->seq);
···
786
790
*timerlat_init_top(struct common_params *params)
787
791
{
788
792
struct osnoise_tool *top;
789
-
int nr_cpus;
790
-
791
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
792
793
793
794
top = osnoise_init_tool("timerlat_top");
794
795
if (!top)
+1
-2
tools/tracing/rtla/src/timerlat_u.c
+1
-2
tools/tracing/rtla/src/timerlat_u.c
···
16
16
#include <sys/wait.h>
17
17
#include <sys/prctl.h>
18
18
19
-
#include "utils.h"
19
+
#include "common.h"
20
20
#include "timerlat_u.h"
21
21
22
22
/*
···
131
131
*/
132
132
void *timerlat_u_dispatcher(void *data)
133
133
{
134
-
int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
135
134
struct timerlat_u_params *params = data;
136
135
char proc_name[128];
137
136
int procs_count = 0;
+1
tools/tracing/rtla/src/timerlat_u.h
+1
tools/tracing/rtla/src/timerlat_u.h
+1
-9
tools/tracing/rtla/src/utils.c
+1
-9
tools/tracing/rtla/src/utils.c
···
19
19
#include <stdio.h>
20
20
#include <limits.h>
21
21
22
-
#include "utils.h"
22
+
#include "common.h"
23
23
24
24
#define MAX_MSG_LENGTH 1024
25
25
int config_debug;
···
119
119
{
120
120
const char *p;
121
121
int end_cpu;
122
-
int nr_cpus;
123
122
int cpu;
124
123
int i;
125
124
126
125
CPU_ZERO(set);
127
-
128
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
129
126
130
127
for (p = cpu_list; *p; ) {
131
128
cpu = atoi(p);
···
574
577
unsigned int nr_states;
575
578
unsigned int state;
576
579
int disabled;
577
-
int nr_cpus;
578
580
579
581
nr_states = cpuidle_state_count(cpu);
580
582
···
581
585
return 0;
582
586
583
587
if (saved_cpu_idle_disable_state == NULL) {
584
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
585
588
saved_cpu_idle_disable_state = calloc(nr_cpus, sizeof(unsigned int *));
586
589
if (!saved_cpu_idle_disable_state)
587
590
return -1;
···
657
662
void free_cpu_idle_disable_states(void)
658
663
{
659
664
int cpu;
660
-
int nr_cpus;
661
665
662
666
if (!saved_cpu_idle_disable_state)
663
667
return;
664
-
665
-
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
666
668
667
669
for (cpu = 0; cpu < nr_cpus; cpu++) {
668
670
free(saved_cpu_idle_disable_state[cpu]);
+18
-22
tools/tracing/rtla/tests/unit/unit_tests.c
+18
-22
tools/tracing/rtla/tests/unit/unit_tests.c
···
7
7
#include <sched.h>
8
8
#include <limits.h>
9
9
#include <unistd.h>
10
+
#include <sys/sysinfo.h>
10
11
11
12
#include "../../src/utils.h"
13
+
int nr_cpus;
12
14
13
15
START_TEST(test_strtoi)
14
16
{
···
36
34
START_TEST(test_parse_cpu_set)
37
35
{
38
36
cpu_set_t set;
39
-
int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
40
37
38
+
nr_cpus = 8;
41
39
ck_assert_int_eq(parse_cpu_set("0", &set), 0);
42
40
ck_assert(CPU_ISSET(0, &set));
43
41
ck_assert(!CPU_ISSET(1, &set));
44
42
45
-
if (nr_cpus > 2) {
46
-
ck_assert_int_eq(parse_cpu_set("0,2", &set), 0);
47
-
ck_assert(CPU_ISSET(0, &set));
48
-
ck_assert(CPU_ISSET(2, &set));
49
-
}
43
+
ck_assert_int_eq(parse_cpu_set("0,2", &set), 0);
44
+
ck_assert(CPU_ISSET(0, &set));
45
+
ck_assert(CPU_ISSET(2, &set));
50
46
51
-
if (nr_cpus > 3) {
52
-
ck_assert_int_eq(parse_cpu_set("0-3", &set), 0);
53
-
ck_assert(CPU_ISSET(0, &set));
54
-
ck_assert(CPU_ISSET(1, &set));
55
-
ck_assert(CPU_ISSET(2, &set));
56
-
ck_assert(CPU_ISSET(3, &set));
57
-
}
47
+
ck_assert_int_eq(parse_cpu_set("0-3", &set), 0);
48
+
ck_assert(CPU_ISSET(0, &set));
49
+
ck_assert(CPU_ISSET(1, &set));
50
+
ck_assert(CPU_ISSET(2, &set));
51
+
ck_assert(CPU_ISSET(3, &set));
58
52
59
-
if (nr_cpus > 5) {
60
-
ck_assert_int_eq(parse_cpu_set("1-3,5", &set), 0);
61
-
ck_assert(!CPU_ISSET(0, &set));
62
-
ck_assert(CPU_ISSET(1, &set));
63
-
ck_assert(CPU_ISSET(2, &set));
64
-
ck_assert(CPU_ISSET(3, &set));
65
-
ck_assert(!CPU_ISSET(4, &set));
66
-
ck_assert(CPU_ISSET(5, &set));
67
-
}
53
+
ck_assert_int_eq(parse_cpu_set("1-3,5", &set), 0);
54
+
ck_assert(!CPU_ISSET(0, &set));
55
+
ck_assert(CPU_ISSET(1, &set));
56
+
ck_assert(CPU_ISSET(2, &set));
57
+
ck_assert(CPU_ISSET(3, &set));
58
+
ck_assert(!CPU_ISSET(4, &set));
59
+
ck_assert(CPU_ISSET(5, &set));
68
60
69
61
ck_assert_int_eq(parse_cpu_set("-1", &set), 1);
70
62
ck_assert_int_eq(parse_cpu_set("abc", &set), 1);