1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (c) 2022 Meta Platforms, Inc. and affiliates.
4 * Copyright (c) 2022 Tejun Heo <tj@kernel.org>
5 * Copyright (c) 2022 David Vernet <dvernet@meta.com>
6 */
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <unistd.h>
10 #include <inttypes.h>
11 #include <signal.h>
12 #include <libgen.h>
13 #include <bpf/bpf.h>
14 #include <scx/common.h>
15 #include "scx_qmap.bpf.skel.h"
16
17 const char help_fmt[] =
18 "A simple five-level FIFO queue sched_ext scheduler.\n"
19 "\n"
20 "See the top-level comment in .bpf.c for more details.\n"
21 "\n"
22 "Usage: %s [-s SLICE_US] [-e COUNT] [-t COUNT] [-T COUNT] [-l COUNT] [-b COUNT]\n"
23 " [-P] [-d PID] [-D LEN] [-p] [-v]\n"
24 "\n"
25 " -s SLICE_US Override slice duration\n"
26 " -e COUNT Trigger scx_bpf_error() after COUNT enqueues\n"
27 " -t COUNT Stall every COUNT'th user thread\n"
28 " -T COUNT Stall every COUNT'th kernel thread\n"
29 " -l COUNT Trigger dispatch infinite looping after COUNT dispatches\n"
30 " -b COUNT Dispatch upto COUNT tasks together\n"
31 " -P Print out DSQ content to trace_pipe every second, use with -b\n"
32 " -H Boost nice -20 tasks in SHARED_DSQ, use with -b\n"
33 " -d PID Disallow a process from switching into SCHED_EXT (-1 for self)\n"
34 " -D LEN Set scx_exit_info.dump buffer length\n"
35 " -S Suppress qmap-specific debug dump\n"
36 " -p Switch only tasks on SCHED_EXT policy instead of all\n"
37 " -v Print libbpf debug messages\n"
38 " -h Display this help and exit\n";
39
40 static bool verbose;
41 static volatile int exit_req;
42
43 static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args)
44 {
45 if (level == LIBBPF_DEBUG && !verbose)
46 return 0;
47 return vfprintf(stderr, format, args);
48 }
49
50 static void sigint_handler(int dummy)
51 {
52 exit_req = 1;
53 }
54
55 int main(int argc, char **argv)
56 {
57 struct scx_qmap *skel;
58 struct bpf_link *link;
59 int opt;
60
61 libbpf_set_print(libbpf_print_fn);
62 signal(SIGINT, sigint_handler);
63 signal(SIGTERM, sigint_handler);
64
65 skel = SCX_OPS_OPEN(qmap_ops, scx_qmap);
66
67 while ((opt = getopt(argc, argv, "s:e:t:T:l:b:PHd:D:Spvh")) != -1) {
68 switch (opt) {
69 case 's':
70 skel->rodata->slice_ns = strtoull(optarg, NULL, 0) * 1000;
71 break;
72 case 'e':
73 skel->bss->test_error_cnt = strtoul(optarg, NULL, 0);
74 break;
75 case 't':
76 skel->rodata->stall_user_nth = strtoul(optarg, NULL, 0);
77 break;
78 case 'T':
79 skel->rodata->stall_kernel_nth = strtoul(optarg, NULL, 0);
80 break;
81 case 'l':
82 skel->rodata->dsp_inf_loop_after = strtoul(optarg, NULL, 0);
83 break;
84 case 'b':
85 skel->rodata->dsp_batch = strtoul(optarg, NULL, 0);
86 break;
87 case 'P':
88 skel->rodata->print_shared_dsq = true;
89 break;
90 case 'H':
91 skel->rodata->highpri_boosting = true;
92 break;
93 case 'd':
94 skel->rodata->disallow_tgid = strtol(optarg, NULL, 0);
95 if (skel->rodata->disallow_tgid < 0)
96 skel->rodata->disallow_tgid = getpid();
97 break;
98 case 'D':
99 skel->struct_ops.qmap_ops->exit_dump_len = strtoul(optarg, NULL, 0);
100 break;
101 case 'S':
102 skel->rodata->suppress_dump = true;
103 break;
104 case 'p':
105 skel->struct_ops.qmap_ops->flags |= SCX_OPS_SWITCH_PARTIAL;
106 break;
107 case 'v':
108 verbose = true;
109 break;
110 default:
111 fprintf(stderr, help_fmt, basename(argv[0]));
112 return opt != 'h';
113 }
114 }
115
116 SCX_OPS_LOAD(skel, qmap_ops, scx_qmap, uei);
117 link = SCX_OPS_ATTACH(skel, qmap_ops, scx_qmap);
118
119 while (!exit_req && !UEI_EXITED(skel, uei)) {
120 long nr_enqueued = skel->bss->nr_enqueued;
121 long nr_dispatched = skel->bss->nr_dispatched;
122
123 printf("stats : enq=%lu dsp=%lu delta=%ld reenq=%"PRIu64" deq=%"PRIu64" core=%"PRIu64" enq_ddsp=%"PRIu64"\n",
124 nr_enqueued, nr_dispatched, nr_enqueued - nr_dispatched,
125 skel->bss->nr_reenqueued, skel->bss->nr_dequeued,
126 skel->bss->nr_core_sched_execed,
127 skel->bss->nr_ddsp_from_enq);
128 printf(" exp_local=%"PRIu64" exp_remote=%"PRIu64" exp_timer=%"PRIu64" exp_lost=%"PRIu64"\n",
129 skel->bss->nr_expedited_local,
130 skel->bss->nr_expedited_remote,
131 skel->bss->nr_expedited_from_timer,
132 skel->bss->nr_expedited_lost);
133 if (__COMPAT_has_ksym("scx_bpf_cpuperf_cur"))
134 printf("cpuperf: cur min/avg/max=%u/%u/%u target min/avg/max=%u/%u/%u\n",
135 skel->bss->cpuperf_min,
136 skel->bss->cpuperf_avg,
137 skel->bss->cpuperf_max,
138 skel->bss->cpuperf_target_min,
139 skel->bss->cpuperf_target_avg,
140 skel->bss->cpuperf_target_max);
141 fflush(stdout);
142 sleep(1);
143 }
144
145 bpf_link__destroy(link);
146 UEI_REPORT(skel, uei);
147 scx_qmap__destroy(skel);
148 /*
149 * scx_qmap implements ops.cpu_on/offline() and doesn't need to restart
150 * on CPU hotplug events.
151 */
152 return 0;
153 }
154
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