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authorLinus Torvalds <torvalds@linux-foundation.org>2020-01-28 16:02:33 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-01-28 16:02:33 -0800
commitbd2463ac7d7ec51d432f23bf0e893fb371a908cd (patch)
tree3da32c23be83adb9d9bda7e51b51fa39f69f2447 /tools/bpf/runqslower/runqslower.c
parenta78208e2436963d0b2c7d186277d6e1a9755029a (diff)
parentf76e4c167ea2212e23c15ee7e601a865e822c291 (diff)
downloadlinux-bd2463ac7d7ec51d432f23bf0e893fb371a908cd.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller: 1) Add WireGuard 2) Add HE and TWT support to ath11k driver, from John Crispin. 3) Add ESP in TCP encapsulation support, from Sabrina Dubroca. 4) Add variable window congestion control to TIPC, from Jon Maloy. 5) Add BCM84881 PHY driver, from Russell King. 6) Start adding netlink support for ethtool operations, from Michal Kubecek. 7) Add XDP drop and TX action support to ena driver, from Sameeh Jubran. 8) Add new ipv4 route notifications so that mlxsw driver does not have to handle identical routes itself. From Ido Schimmel. 9) Add BPF dynamic program extensions, from Alexei Starovoitov. 10) Support RX and TX timestamping in igc, from Vinicius Costa Gomes. 11) Add support for macsec HW offloading, from Antoine Tenart. 12) Add initial support for MPTCP protocol, from Christoph Paasch, Matthieu Baerts, Florian Westphal, Peter Krystad, and many others. 13) Add Octeontx2 PF support, from Sunil Goutham, Geetha sowjanya, Linu Cherian, and others. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1469 commits) net: phy: add default ARCH_BCM_IPROC for MDIO_BCM_IPROC udp: segment looped gso packets correctly netem: change mailing list qed: FW 8.42.2.0 debug features qed: rt init valid initialization changed qed: Debug feature: ilt and mdump qed: FW 8.42.2.0 Add fw overlay feature qed: FW 8.42.2.0 HSI changes qed: FW 8.42.2.0 iscsi/fcoe changes qed: Add abstraction for different hsi values per chip qed: FW 8.42.2.0 Additional ll2 type qed: Use dmae to write to widebus registers in fw_funcs qed: FW 8.42.2.0 Parser offsets modified qed: FW 8.42.2.0 Queue Manager changes qed: FW 8.42.2.0 Expose new registers and change windows qed: FW 8.42.2.0 Internal ram offsets modifications MAINTAINERS: Add entry for Marvell OcteonTX2 Physical Function driver Documentation: net: octeontx2: Add RVU HW and drivers overview octeontx2-pf: ethtool RSS config support octeontx2-pf: Add basic ethtool support ...
Diffstat (limited to 'tools/bpf/runqslower/runqslower.c')
-rw-r--r--tools/bpf/runqslower/runqslower.c187
1 files changed, 187 insertions, 0 deletions
diff --git a/tools/bpf/runqslower/runqslower.c b/tools/bpf/runqslower/runqslower.c
new file mode 100644
index 000000000000..d89715844952
--- /dev/null
+++ b/tools/bpf/runqslower/runqslower.c
@@ -0,0 +1,187 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+// Copyright (c) 2019 Facebook
+#include <argp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/resource.h>
+#include <time.h>
+#include <bpf/libbpf.h>
+#include <bpf/bpf.h>
+#include "runqslower.h"
+#include "runqslower.skel.h"
+
+struct env {
+ pid_t pid;
+ __u64 min_us;
+ bool verbose;
+} env = {
+ .min_us = 10000,
+};
+
+const char *argp_program_version = "runqslower 0.1";
+const char *argp_program_bug_address = "<bpf@vger.kernel.org>";
+const char argp_program_doc[] =
+"runqslower Trace long process scheduling delays.\n"
+" For Linux, uses eBPF, BPF CO-RE, libbpf, BTF.\n"
+"\n"
+"This script traces high scheduling delays between tasks being\n"
+"ready to run and them running on CPU after that.\n"
+"\n"
+"USAGE: runqslower [-p PID] [min_us]\n"
+"\n"
+"EXAMPLES:\n"
+" runqslower # trace run queue latency higher than 10000 us (default)\n"
+" runqslower 1000 # trace run queue latency higher than 1000 us\n"
+" runqslower -p 123 # trace pid 123 only\n";
+
+static const struct argp_option opts[] = {
+ { "pid", 'p', "PID", 0, "Process PID to trace"},
+ { "verbose", 'v', NULL, 0, "Verbose debug output" },
+ {},
+};
+
+static error_t parse_arg(int key, char *arg, struct argp_state *state)
+{
+ static int pos_args;
+ int pid;
+ long long min_us;
+
+ switch (key) {
+ case 'v':
+ env.verbose = true;
+ break;
+ case 'p':
+ errno = 0;
+ pid = strtol(arg, NULL, 10);
+ if (errno || pid <= 0) {
+ fprintf(stderr, "Invalid PID: %s\n", arg);
+ argp_usage(state);
+ }
+ env.pid = pid;
+ break;
+ case ARGP_KEY_ARG:
+ if (pos_args++) {
+ fprintf(stderr,
+ "Unrecognized positional argument: %s\n", arg);
+ argp_usage(state);
+ }
+ errno = 0;
+ min_us = strtoll(arg, NULL, 10);
+ if (errno || min_us <= 0) {
+ fprintf(stderr, "Invalid delay (in us): %s\n", arg);
+ argp_usage(state);
+ }
+ env.min_us = min_us;
+ break;
+ default:
+ return ARGP_ERR_UNKNOWN;
+ }
+ return 0;
+}
+
+int libbpf_print_fn(enum libbpf_print_level level,
+ const char *format, va_list args)
+{
+ if (level == LIBBPF_DEBUG && !env.verbose)
+ return 0;
+ return vfprintf(stderr, format, args);
+}
+
+static int bump_memlock_rlimit(void)
+{
+ struct rlimit rlim_new = {
+ .rlim_cur = RLIM_INFINITY,
+ .rlim_max = RLIM_INFINITY,
+ };
+
+ return setrlimit(RLIMIT_MEMLOCK, &rlim_new);
+}
+
+void handle_event(void *ctx, int cpu, void *data, __u32 data_sz)
+{
+ const struct event *e = data;
+ struct tm *tm;
+ char ts[32];
+ time_t t;
+
+ time(&t);
+ tm = localtime(&t);
+ strftime(ts, sizeof(ts), "%H:%M:%S", tm);
+ printf("%-8s %-16s %-6d %14llu\n", ts, e->task, e->pid, e->delta_us);
+}
+
+void handle_lost_events(void *ctx, int cpu, __u64 lost_cnt)
+{
+ printf("Lost %llu events on CPU #%d!\n", lost_cnt, cpu);
+}
+
+int main(int argc, char **argv)
+{
+ static const struct argp argp = {
+ .options = opts,
+ .parser = parse_arg,
+ .doc = argp_program_doc,
+ };
+ struct perf_buffer_opts pb_opts;
+ struct perf_buffer *pb = NULL;
+ struct runqslower_bpf *obj;
+ int err;
+
+ err = argp_parse(&argp, argc, argv, 0, NULL, NULL);
+ if (err)
+ return err;
+
+ libbpf_set_print(libbpf_print_fn);
+
+ err = bump_memlock_rlimit();
+ if (err) {
+ fprintf(stderr, "failed to increase rlimit: %d", err);
+ return 1;
+ }
+
+ obj = runqslower_bpf__open();
+ if (!obj) {
+ fprintf(stderr, "failed to open and/or load BPF object\n");
+ return 1;
+ }
+
+ /* initialize global data (filtering options) */
+ obj->rodata->targ_pid = env.pid;
+ obj->rodata->min_us = env.min_us;
+
+ err = runqslower_bpf__load(obj);
+ if (err) {
+ fprintf(stderr, "failed to load BPF object: %d\n", err);
+ goto cleanup;
+ }
+
+ err = runqslower_bpf__attach(obj);
+ if (err) {
+ fprintf(stderr, "failed to attach BPF programs\n");
+ goto cleanup;
+ }
+
+ printf("Tracing run queue latency higher than %llu us\n", env.min_us);
+ printf("%-8s %-16s %-6s %14s\n", "TIME", "COMM", "PID", "LAT(us)");
+
+ pb_opts.sample_cb = handle_event;
+ pb_opts.lost_cb = handle_lost_events;
+ pb = perf_buffer__new(bpf_map__fd(obj->maps.events), 64, &pb_opts);
+ err = libbpf_get_error(pb);
+ if (err) {
+ pb = NULL;
+ fprintf(stderr, "failed to open perf buffer: %d\n", err);
+ goto cleanup;
+ }
+
+ while ((err = perf_buffer__poll(pb, 100)) >= 0)
+ ;
+ printf("Error polling perf buffer: %d\n", err);
+
+cleanup:
+ perf_buffer__free(pb);
+ runqslower_bpf__destroy(obj);
+
+ return err != 0;
+}