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
17const 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] [-M] [-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 and event counters to trace_pipe every second\n"
32" -M Print out debug messages to trace_pipe\n"
33" -H Boost nice -20 tasks in SHARED_DSQ, use with -b\n"
34" -d PID Disallow a process from switching into SCHED_EXT (-1 for self)\n"
35" -D LEN Set scx_exit_info.dump buffer length\n"
36" -S Suppress qmap-specific debug dump\n"
37" -p Switch only tasks on SCHED_EXT policy instead of all\n"
38" -v Print libbpf debug messages\n"
39" -h Display this help and exit\n";
40
41static bool verbose;
42static volatile int exit_req;
43
44static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args)
45{
46 if (level == LIBBPF_DEBUG && !verbose)
47 return 0;
48 return vfprintf(stderr, format, args);
49}
50
51static void sigint_handler(int dummy)
52{
53 exit_req = 1;
54}
55
56int main(int argc, char **argv)
57{
58 struct scx_qmap *skel;
59 struct bpf_link *link;
60 int opt;
61
62 libbpf_set_print(libbpf_print_fn);
63 signal(SIGINT, sigint_handler);
64 signal(SIGTERM, sigint_handler);
65
66 skel = SCX_OPS_OPEN(qmap_ops, scx_qmap);
67
68 skel->rodata->slice_ns = __COMPAT_ENUM_OR_ZERO("scx_public_consts", "SCX_SLICE_DFL");
69
70 while ((opt = getopt(argc, argv, "s:e:t:T:l:b:PMHd:D:Spvh")) != -1) {
71 switch (opt) {
72 case 's':
73 skel->rodata->slice_ns = strtoull(optarg, NULL, 0) * 1000;
74 break;
75 case 'e':
76 skel->bss->test_error_cnt = strtoul(optarg, NULL, 0);
77 break;
78 case 't':
79 skel->rodata->stall_user_nth = strtoul(optarg, NULL, 0);
80 break;
81 case 'T':
82 skel->rodata->stall_kernel_nth = strtoul(optarg, NULL, 0);
83 break;
84 case 'l':
85 skel->rodata->dsp_inf_loop_after = strtoul(optarg, NULL, 0);
86 break;
87 case 'b':
88 skel->rodata->dsp_batch = strtoul(optarg, NULL, 0);
89 break;
90 case 'P':
91 skel->rodata->print_dsqs_and_events = true;
92 break;
93 case 'M':
94 skel->rodata->print_msgs = true;
95 break;
96 case 'H':
97 skel->rodata->highpri_boosting = true;
98 break;
99 case 'd':
100 skel->rodata->disallow_tgid = strtol(optarg, NULL, 0);
101 if (skel->rodata->disallow_tgid < 0)
102 skel->rodata->disallow_tgid = getpid();
103 break;
104 case 'D':
105 skel->struct_ops.qmap_ops->exit_dump_len = strtoul(optarg, NULL, 0);
106 break;
107 case 'S':
108 skel->rodata->suppress_dump = true;
109 break;
110 case 'p':
111 skel->struct_ops.qmap_ops->flags |= SCX_OPS_SWITCH_PARTIAL;
112 break;
113 case 'v':
114 verbose = true;
115 break;
116 default:
117 fprintf(stderr, help_fmt, basename(argv[0]));
118 return opt != 'h';
119 }
120 }
121
122 SCX_OPS_LOAD(skel, qmap_ops, scx_qmap, uei);
123 link = SCX_OPS_ATTACH(skel, qmap_ops, scx_qmap);
124
125 while (!exit_req && !UEI_EXITED(skel, uei)) {
126 long nr_enqueued = skel->bss->nr_enqueued;
127 long nr_dispatched = skel->bss->nr_dispatched;
128
129 printf("stats : enq=%lu dsp=%lu delta=%ld reenq=%"PRIu64" deq=%"PRIu64" core=%"PRIu64" enq_ddsp=%"PRIu64"\n",
130 nr_enqueued, nr_dispatched, nr_enqueued - nr_dispatched,
131 skel->bss->nr_reenqueued, skel->bss->nr_dequeued,
132 skel->bss->nr_core_sched_execed,
133 skel->bss->nr_ddsp_from_enq);
134 printf(" exp_local=%"PRIu64" exp_remote=%"PRIu64" exp_timer=%"PRIu64" exp_lost=%"PRIu64"\n",
135 skel->bss->nr_expedited_local,
136 skel->bss->nr_expedited_remote,
137 skel->bss->nr_expedited_from_timer,
138 skel->bss->nr_expedited_lost);
139 if (__COMPAT_has_ksym("scx_bpf_cpuperf_cur"))
140 printf("cpuperf: cur min/avg/max=%u/%u/%u target min/avg/max=%u/%u/%u\n",
141 skel->bss->cpuperf_min,
142 skel->bss->cpuperf_avg,
143 skel->bss->cpuperf_max,
144 skel->bss->cpuperf_target_min,
145 skel->bss->cpuperf_target_avg,
146 skel->bss->cpuperf_target_max);
147 fflush(stdout);
148 sleep(1);
149 }
150
151 bpf_link__destroy(link);
152 UEI_REPORT(skel, uei);
153 scx_qmap__destroy(skel);
154 /*
155 * scx_qmap implements ops.cpu_on/offline() and doesn't need to restart
156 * on CPU hotplug events.
157 */
158 return 0;
159}
160

source code of linux/tools/sched_ext/scx_qmap.c