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 <sys/stat.h> 14 #include <bpf/bpf.h> 15 #include <scx/common.h> 16 #include "scx_qmap.bpf.skel.h" 17 18 const char help_fmt[] = 19 "A simple five-level FIFO queue sched_ext scheduler.\n" 20 "\n" 21 "See the top-level comment in .bpf.c for more details.\n" 22 "\n" 23 "Usage: %s [-s SLICE_US] [-e COUNT] [-t COUNT] [-T COUNT] [-l COUNT] [-b COUNT]\n" 24 " [-P] [-M] [-H] [-d PID] [-D LEN] [-S] [-p] [-v]\n" 25 "\n" 26 " -s SLICE_US Override slice duration\n" 27 " -e COUNT Trigger scx_bpf_error() after COUNT enqueues\n" 28 " -t COUNT Stall every COUNT'th user thread\n" 29 " -T COUNT Stall every COUNT'th kernel thread\n" 30 " -l COUNT Trigger dispatch infinite looping after COUNT dispatches\n" 31 " -b COUNT Dispatch upto COUNT tasks together\n" 32 " -P Print out DSQ content and event counters to trace_pipe every second\n" 33 " -M Print out debug messages to trace_pipe\n" 34 " -H Boost nice -20 tasks in SHARED_DSQ, use with -b\n" 35 " -d PID Disallow a process from switching into SCHED_EXT (-1 for self)\n" 36 " -D LEN Set scx_exit_info.dump buffer length\n" 37 " -S Suppress qmap-specific debug dump\n" 38 " -p Switch only tasks on SCHED_EXT policy instead of all\n" 39 " -v Print libbpf debug messages\n" 40 " -h Display this help and exit\n"; 41 42 static bool verbose; 43 static volatile int exit_req; 44 45 static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args) 46 { 47 if (level == LIBBPF_DEBUG && !verbose) 48 return 0; 49 return vfprintf(stderr, format, args); 50 } 51 52 static void sigint_handler(int dummy) 53 { 54 exit_req = 1; 55 } 56 57 int main(int argc, char **argv) 58 { 59 struct scx_qmap *skel; 60 struct bpf_link *link; 61 int opt; 62 63 libbpf_set_print(libbpf_print_fn); 64 signal(SIGINT, sigint_handler); 65 signal(SIGTERM, sigint_handler); 66 67 skel = SCX_OPS_OPEN(qmap_ops, scx_qmap); 68 69 skel->rodata->slice_ns = __COMPAT_ENUM_OR_ZERO("scx_public_consts", "SCX_SLICE_DFL"); 70 71 while ((opt = getopt(argc, argv, "s:e:t:T:l:b:PMHc:d:D:Spvh")) != -1) { 72 switch (opt) { 73 case 's': 74 skel->rodata->slice_ns = strtoull(optarg, NULL, 0) * 1000; 75 break; 76 case 'e': 77 skel->bss->test_error_cnt = strtoul(optarg, NULL, 0); 78 break; 79 case 't': 80 skel->rodata->stall_user_nth = strtoul(optarg, NULL, 0); 81 break; 82 case 'T': 83 skel->rodata->stall_kernel_nth = strtoul(optarg, NULL, 0); 84 break; 85 case 'l': 86 skel->rodata->dsp_inf_loop_after = strtoul(optarg, NULL, 0); 87 break; 88 case 'b': 89 skel->rodata->dsp_batch = strtoul(optarg, NULL, 0); 90 break; 91 case 'P': 92 skel->rodata->print_dsqs_and_events = true; 93 break; 94 case 'M': 95 skel->rodata->print_msgs = true; 96 break; 97 case 'H': 98 skel->rodata->highpri_boosting = true; 99 break; 100 case 'c': { 101 struct stat st; 102 if (stat(optarg, &st) < 0) { 103 perror("stat"); 104 return 1; 105 } 106 skel->struct_ops.qmap_ops->sub_cgroup_id = st.st_ino; 107 skel->rodata->sub_cgroup_id = st.st_ino; 108 break; 109 } 110 case 'd': 111 skel->rodata->disallow_tgid = strtol(optarg, NULL, 0); 112 if (skel->rodata->disallow_tgid < 0) 113 skel->rodata->disallow_tgid = getpid(); 114 break; 115 case 'D': 116 skel->struct_ops.qmap_ops->exit_dump_len = strtoul(optarg, NULL, 0); 117 break; 118 case 'S': 119 skel->rodata->suppress_dump = true; 120 break; 121 case 'p': 122 skel->struct_ops.qmap_ops->flags |= SCX_OPS_SWITCH_PARTIAL; 123 break; 124 case 'v': 125 verbose = true; 126 break; 127 default: 128 fprintf(stderr, help_fmt, basename(argv[0])); 129 return opt != 'h'; 130 } 131 } 132 133 SCX_OPS_LOAD(skel, qmap_ops, scx_qmap, uei); 134 link = SCX_OPS_ATTACH(skel, qmap_ops, scx_qmap); 135 136 while (!exit_req && !UEI_EXITED(skel, uei)) { 137 long nr_enqueued = skel->bss->nr_enqueued; 138 long nr_dispatched = skel->bss->nr_dispatched; 139 140 printf("stats : enq=%lu dsp=%lu delta=%ld reenq/cpu0=%"PRIu64"/%"PRIu64" deq=%"PRIu64" core=%"PRIu64" enq_ddsp=%"PRIu64"\n", 141 nr_enqueued, nr_dispatched, nr_enqueued - nr_dispatched, 142 skel->bss->nr_reenqueued, skel->bss->nr_reenqueued_cpu0, 143 skel->bss->nr_dequeued, 144 skel->bss->nr_core_sched_execed, 145 skel->bss->nr_ddsp_from_enq); 146 printf(" exp_local=%"PRIu64" exp_remote=%"PRIu64" exp_timer=%"PRIu64" exp_lost=%"PRIu64"\n", 147 skel->bss->nr_expedited_local, 148 skel->bss->nr_expedited_remote, 149 skel->bss->nr_expedited_from_timer, 150 skel->bss->nr_expedited_lost); 151 if (__COMPAT_has_ksym("scx_bpf_cpuperf_cur")) 152 printf("cpuperf: cur min/avg/max=%u/%u/%u target min/avg/max=%u/%u/%u\n", 153 skel->bss->cpuperf_min, 154 skel->bss->cpuperf_avg, 155 skel->bss->cpuperf_max, 156 skel->bss->cpuperf_target_min, 157 skel->bss->cpuperf_target_avg, 158 skel->bss->cpuperf_target_max); 159 fflush(stdout); 160 sleep(1); 161 } 162 163 bpf_link__destroy(link); 164 UEI_REPORT(skel, uei); 165 scx_qmap__destroy(skel); 166 /* 167 * scx_qmap implements ops.cpu_on/offline() and doesn't need to restart 168 * on CPU hotplug events. 169 */ 170 return 0; 171 } 172