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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/perf/util/bpf_lock_contention.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/perf/util/bpf_lock_contention.c')
-rw-r--r--tools/perf/util/bpf_lock_contention.c195
1 files changed, 195 insertions, 0 deletions
diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c
new file mode 100644
index 000000000..fc4d613cb
--- /dev/null
+++ b/tools/perf/util/bpf_lock_contention.c
@@ -0,0 +1,195 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "util/debug.h"
+#include "util/evlist.h"
+#include "util/machine.h"
+#include "util/map.h"
+#include "util/symbol.h"
+#include "util/target.h"
+#include "util/thread_map.h"
+#include "util/lock-contention.h"
+#include <linux/zalloc.h>
+#include <linux/string.h>
+#include <bpf/bpf.h>
+
+#include "bpf_skel/lock_contention.skel.h"
+
+static struct lock_contention_bpf *skel;
+
+struct lock_contention_data {
+ u64 total_time;
+ u64 min_time;
+ u64 max_time;
+ u32 count;
+ u32 flags;
+};
+
+int lock_contention_prepare(struct lock_contention *con)
+{
+ int i, fd;
+ int ncpus = 1, ntasks = 1;
+ struct evlist *evlist = con->evlist;
+ struct target *target = con->target;
+
+ skel = lock_contention_bpf__open();
+ if (!skel) {
+ pr_err("Failed to open lock-contention BPF skeleton\n");
+ return -1;
+ }
+
+ bpf_map__set_value_size(skel->maps.stacks, con->max_stack * sizeof(u64));
+ bpf_map__set_max_entries(skel->maps.stacks, con->map_nr_entries);
+ bpf_map__set_max_entries(skel->maps.lock_stat, con->map_nr_entries);
+
+ if (target__has_cpu(target))
+ ncpus = perf_cpu_map__nr(evlist->core.user_requested_cpus);
+ if (target__has_task(target))
+ ntasks = perf_thread_map__nr(evlist->core.threads);
+
+ bpf_map__set_max_entries(skel->maps.cpu_filter, ncpus);
+ bpf_map__set_max_entries(skel->maps.task_filter, ntasks);
+
+ if (lock_contention_bpf__load(skel) < 0) {
+ pr_err("Failed to load lock-contention BPF skeleton\n");
+ return -1;
+ }
+
+ if (target__has_cpu(target)) {
+ u32 cpu;
+ u8 val = 1;
+
+ skel->bss->has_cpu = 1;
+ fd = bpf_map__fd(skel->maps.cpu_filter);
+
+ for (i = 0; i < ncpus; i++) {
+ cpu = perf_cpu_map__cpu(evlist->core.user_requested_cpus, i).cpu;
+ bpf_map_update_elem(fd, &cpu, &val, BPF_ANY);
+ }
+ }
+
+ if (target__has_task(target)) {
+ u32 pid;
+ u8 val = 1;
+
+ skel->bss->has_task = 1;
+ fd = bpf_map__fd(skel->maps.task_filter);
+
+ for (i = 0; i < ntasks; i++) {
+ pid = perf_thread_map__pid(evlist->core.threads, i);
+ bpf_map_update_elem(fd, &pid, &val, BPF_ANY);
+ }
+ }
+
+ if (target__none(target) && evlist->workload.pid > 0) {
+ u32 pid = evlist->workload.pid;
+ u8 val = 1;
+
+ skel->bss->has_task = 1;
+ fd = bpf_map__fd(skel->maps.task_filter);
+ bpf_map_update_elem(fd, &pid, &val, BPF_ANY);
+ }
+
+ skel->bss->stack_skip = con->stack_skip;
+
+ lock_contention_bpf__attach(skel);
+ return 0;
+}
+
+int lock_contention_start(void)
+{
+ skel->bss->enabled = 1;
+ return 0;
+}
+
+int lock_contention_stop(void)
+{
+ skel->bss->enabled = 0;
+ return 0;
+}
+
+int lock_contention_read(struct lock_contention *con)
+{
+ int fd, stack;
+ s32 prev_key, key;
+ struct lock_contention_data data;
+ struct lock_stat *st;
+ struct machine *machine = con->machine;
+ u64 stack_trace[con->max_stack];
+
+ fd = bpf_map__fd(skel->maps.lock_stat);
+ stack = bpf_map__fd(skel->maps.stacks);
+
+ con->lost = skel->bss->lost;
+
+ prev_key = 0;
+ while (!bpf_map_get_next_key(fd, &prev_key, &key)) {
+ struct map *kmap;
+ struct symbol *sym;
+ int idx = 0;
+
+ bpf_map_lookup_elem(fd, &key, &data);
+ st = zalloc(sizeof(*st));
+ if (st == NULL)
+ return -1;
+
+ st->nr_contended = data.count;
+ st->wait_time_total = data.total_time;
+ st->wait_time_max = data.max_time;
+ st->wait_time_min = data.min_time;
+
+ if (data.count)
+ st->avg_wait_time = data.total_time / data.count;
+
+ st->flags = data.flags;
+
+ bpf_map_lookup_elem(stack, &key, stack_trace);
+
+ /* skip lock internal functions */
+ while (is_lock_function(machine, stack_trace[idx]) &&
+ idx < con->max_stack - 1)
+ idx++;
+
+ st->addr = stack_trace[idx];
+ sym = machine__find_kernel_symbol(machine, st->addr, &kmap);
+
+ if (sym) {
+ unsigned long offset;
+ int ret = 0;
+
+ offset = kmap->map_ip(kmap, st->addr) - sym->start;
+
+ if (offset)
+ ret = asprintf(&st->name, "%s+%#lx", sym->name, offset);
+ else
+ st->name = strdup(sym->name);
+
+ if (ret < 0 || st->name == NULL)
+ return -1;
+ } else if (asprintf(&st->name, "%#lx", (unsigned long)st->addr) < 0) {
+ free(st);
+ return -1;
+ }
+
+ if (verbose) {
+ st->callstack = memdup(stack_trace, sizeof(stack_trace));
+ if (st->callstack == NULL) {
+ free(st);
+ return -1;
+ }
+ }
+
+ hlist_add_head(&st->hash_entry, con->result);
+ prev_key = key;
+ }
+
+ return 0;
+}
+
+int lock_contention_finish(void)
+{
+ if (skel) {
+ skel->bss->enabled = 0;
+ lock_contention_bpf__destroy(skel);
+ }
+
+ return 0;
+}