diff options
Diffstat (limited to 'tools/perf/util/bpf_skel')
| -rw-r--r-- | tools/perf/util/bpf_skel/off_cpu.bpf.c | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/tools/perf/util/bpf_skel/off_cpu.bpf.c b/tools/perf/util/bpf_skel/off_cpu.bpf.c index 5173ed882fdf..78cdcc8ff863 100644 --- a/tools/perf/util/bpf_skel/off_cpu.bpf.c +++ b/tools/perf/util/bpf_skel/off_cpu.bpf.c @@ -49,12 +49,28 @@ struct { __uint(max_entries, MAX_ENTRIES); } off_cpu SEC(".maps"); +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(__u8)); + __uint(max_entries, 1); +} cpu_filter SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(__u8)); + __uint(max_entries, 1); +} task_filter SEC(".maps"); + /* old kernel task_struct definition */ struct task_struct___old { long state; } __attribute__((preserve_access_index)); int enabled = 0; +int has_cpu = 0; +int has_task = 0; /* * Old kernel used to call it task_struct->state and now it's '__state'. @@ -74,6 +90,37 @@ static inline int get_task_state(struct task_struct *t) return BPF_CORE_READ(t_old, state); } +static inline int can_record(struct task_struct *t, int state) +{ + /* kernel threads don't have user stack */ + if (t->flags & PF_KTHREAD) + return 0; + + if (state != TASK_INTERRUPTIBLE && + state != TASK_UNINTERRUPTIBLE) + return 0; + + if (has_cpu) { + __u32 cpu = bpf_get_smp_processor_id(); + __u8 *ok; + + ok = bpf_map_lookup_elem(&cpu_filter, &cpu); + if (!ok) + return 0; + } + + if (has_task) { + __u8 *ok; + __u32 pid = t->pid; + + ok = bpf_map_lookup_elem(&task_filter, &pid); + if (!ok) + return 0; + } + + return 1; +} + SEC("tp_btf/sched_switch") int on_switch(u64 *ctx) { @@ -92,10 +139,7 @@ int on_switch(u64 *ctx) ts = bpf_ktime_get_ns(); - if (prev->flags & PF_KTHREAD) - goto next; - if (state != TASK_INTERRUPTIBLE && - state != TASK_UNINTERRUPTIBLE) + if (!can_record(prev, state)) goto next; stack_id = bpf_get_stackid(ctx, &stacks, |