Song Liu 856c02dbce bpf: Introduce helper bpf_get_branch_snapshot
Introduce bpf_get_branch_snapshot(), which allows tracing pogram to get
branch trace from hardware (e.g. Intel LBR). To use the feature, the
user need to create perf_event with proper branch_record filtering
on each cpu, and then calls bpf_get_branch_snapshot in the bpf function.
On Intel CPUs, VLBR event (raw event 0x1b00) can be use for this.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210910183352.3151445-3-songliubraving@fb.com
2021-09-13 10:53:50 -07:00
..
2021-09-03 11:22:50 -07:00
2021-09-02 13:00:15 -07:00
2021-08-30 14:26:36 -07:00
2021-08-30 14:26:36 -07:00
2021-08-11 13:11:12 -07:00
2021-06-18 11:43:08 +02:00
2021-05-07 00:26:33 -07:00
2021-07-11 11:06:09 -07:00
2021-06-18 11:43:09 +02:00
2020-12-01 10:30:28 +00:00
2021-08-11 14:47:16 +02:00
2021-05-07 00:26:34 -07:00
2020-08-19 14:13:20 +02:00