perf lock contention: Account contending locks too

[linux-2.6-microblaze.git] / tools / perf / util / bpf_lock_contention.c

diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c
index 31ff19a..3549180 100644 (file)
--- a/tools/perf/util/bpf_lock_contention.c
+++ b/tools/perf/util/bpf_lock_contention.c
@@ -179,6 +179,123 @@ int lock_contention_prepare(struct lock_contention *con)
        return 0;
 }
 
+/*
+ * Run the BPF program directly using BPF_PROG_TEST_RUN to update the end
+ * timestamp in ktime so that it can calculate delta easily.
+ */
+static void mark_end_timestamp(void)
+{
+       DECLARE_LIBBPF_OPTS(bpf_test_run_opts, opts,
+               .flags = BPF_F_TEST_RUN_ON_CPU,
+       );
+       int prog_fd = bpf_program__fd(skel->progs.end_timestamp);
+
+       bpf_prog_test_run_opts(prog_fd, &opts);
+}
+
+static void update_lock_stat(int map_fd, int pid, u64 end_ts,
+                            enum lock_aggr_mode aggr_mode,
+                            struct tstamp_data *ts_data)
+{
+       u64 delta;
+       struct contention_key stat_key = {};
+       struct contention_data stat_data;
+
+       if (ts_data->timestamp >= end_ts)
+               return;
+
+       delta = end_ts - ts_data->timestamp;
+
+       switch (aggr_mode) {
+       case LOCK_AGGR_CALLER:
+               stat_key.stack_id = ts_data->stack_id;
+               break;
+       case LOCK_AGGR_TASK:
+               stat_key.pid = pid;
+               break;
+       case LOCK_AGGR_ADDR:
+               stat_key.lock_addr_or_cgroup = ts_data->lock;
+               break;
+       case LOCK_AGGR_CGROUP:
+               /* TODO */
+               return;
+       default:
+               return;
+       }
+
+       if (bpf_map_lookup_elem(map_fd, &stat_key, &stat_data) < 0)
+               return;
+
+       stat_data.total_time += delta;
+       stat_data.count++;
+
+       if (delta > stat_data.max_time)
+               stat_data.max_time = delta;
+       if (delta < stat_data.min_time)
+               stat_data.min_time = delta;
+
+       bpf_map_update_elem(map_fd, &stat_key, &stat_data, BPF_EXIST);
+}
+
+/*
+ * Account entries in the tstamp map (which didn't see the corresponding
+ * lock:contention_end tracepoint) using end_ts.
+ */
+static void account_end_timestamp(struct lock_contention *con)
+{
+       int ts_fd, stat_fd;
+       int *prev_key, key;
+       u64 end_ts = skel->bss->end_ts;
+       int total_cpus;
+       enum lock_aggr_mode aggr_mode = con->aggr_mode;
+       struct tstamp_data ts_data, *cpu_data;
+
+       /* Iterate per-task tstamp map (key = TID) */
+       ts_fd = bpf_map__fd(skel->maps.tstamp);
+       stat_fd = bpf_map__fd(skel->maps.lock_stat);
+
+       prev_key = NULL;
+       while (!bpf_map_get_next_key(ts_fd, prev_key, &key)) {
+               if (bpf_map_lookup_elem(ts_fd, &key, &ts_data) == 0) {
+                       int pid = key;
+
+                       if (aggr_mode == LOCK_AGGR_TASK && con->owner)
+                               pid = ts_data.flags;
+
+                       update_lock_stat(stat_fd, pid, end_ts, aggr_mode,
+                                        &ts_data);
+               }
+
+               prev_key = &key;
+       }
+
+       /* Now it'll check per-cpu tstamp map which doesn't have TID. */
+       if (aggr_mode == LOCK_AGGR_TASK || aggr_mode == LOCK_AGGR_CGROUP)
+               return;
+
+       total_cpus = cpu__max_cpu().cpu;
+       ts_fd = bpf_map__fd(skel->maps.tstamp_cpu);
+
+       cpu_data = calloc(total_cpus, sizeof(*cpu_data));
+       if (cpu_data == NULL)
+               return;
+
+       prev_key = NULL;
+       while (!bpf_map_get_next_key(ts_fd, prev_key, &key)) {
+               if (bpf_map_lookup_elem(ts_fd, &key, cpu_data) < 0)
+                       goto next;
+
+               for (int i = 0; i < total_cpus; i++) {
+                       update_lock_stat(stat_fd, -1, end_ts, aggr_mode,
+                                        &cpu_data[i]);
+               }
+
+next:
+               prev_key = &key;
+       }
+       free(cpu_data);
+}
+
 int lock_contention_start(void)
 {
        skel->bss->enabled = 1;
@@ -188,6 +305,7 @@ int lock_contention_start(void)
 int lock_contention_stop(void)
 {
        skel->bss->enabled = 0;
+       mark_end_timestamp();
        return 0;
 }
 
@@ -301,6 +419,8 @@ int lock_contention_read(struct lock_contention *con)
        if (stack_trace == NULL)
                return -1;
 
+       account_end_timestamp(con);
+
        if (con->aggr_mode == LOCK_AGGR_TASK) {
                struct thread *idle = __machine__findnew_thread(machine,
                                                                /*pid=*/0,