diff --git a/tools/bpf/runqslower/runqslower.bpf.c b/tools/bpf/runqslower/runqslower.bpf.c index 1f18a409f044..645530ca7e98 100644 --- a/tools/bpf/runqslower/runqslower.bpf.c +++ b/tools/bpf/runqslower/runqslower.bpf.c @@ -11,9 +11,9 @@ const volatile __u64 min_us = 0; const volatile pid_t targ_pid = 0; struct { - __uint(type, BPF_MAP_TYPE_HASH); - __uint(max_entries, 10240); - __type(key, u32); + __uint(type, BPF_MAP_TYPE_TASK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); __type(value, u64); } start SEC(".maps"); @@ -25,15 +25,20 @@ struct { /* record enqueue timestamp */ __always_inline -static int trace_enqueue(u32 tgid, u32 pid) +static int trace_enqueue(struct task_struct *t) { - u64 ts; + u32 pid = t->pid; + u64 *ptr; if (!pid || (targ_pid && targ_pid != pid)) return 0; - ts = bpf_ktime_get_ns(); - bpf_map_update_elem(&start, &pid, &ts, 0); + ptr = bpf_task_storage_get(&start, t, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE); + if (!ptr) + return 0; + + *ptr = bpf_ktime_get_ns(); return 0; } @@ -43,7 +48,7 @@ int handle__sched_wakeup(u64 *ctx) /* TP_PROTO(struct task_struct *p) */ struct task_struct *p = (void *)ctx[0]; - return trace_enqueue(p->tgid, p->pid); + return trace_enqueue(p); } SEC("tp_btf/sched_wakeup_new") @@ -52,7 +57,7 @@ int handle__sched_wakeup_new(u64 *ctx) /* TP_PROTO(struct task_struct *p) */ struct task_struct *p = (void *)ctx[0]; - return trace_enqueue(p->tgid, p->pid); + return trace_enqueue(p); } SEC("tp_btf/sched_switch") @@ -70,12 +75,16 @@ int handle__sched_switch(u64 *ctx) /* ivcsw: treat like an enqueue event and store timestamp */ if (prev->state == TASK_RUNNING) - trace_enqueue(prev->tgid, prev->pid); + trace_enqueue(prev); pid = next->pid; + /* For pid mismatch, save a bpf_task_storage_get */ + if (!pid || (targ_pid && targ_pid != pid)) + return 0; + /* fetch timestamp and calculate delta */ - tsp = bpf_map_lookup_elem(&start, &pid); + tsp = bpf_task_storage_get(&start, next, 0, 0); if (!tsp) return 0; /* missed enqueue */ @@ -91,7 +100,7 @@ int handle__sched_switch(u64 *ctx) bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, &event, sizeof(event)); - bpf_map_delete_elem(&start, &pid); + bpf_task_storage_delete(&start, next); return 0; }