[biosnoop] Revert iovisor#4124

Before the removal of `blk_start_request` in https://patchwork.kernel.org/project/linux-scsi/cover/[email protected]/ we would have needed to trace both `blk_start_request` and `blk_mq_start_request`. Which means that for kernel < 5.0, we need to attach to both tracepoint. For kernels >= 5.0 we can only attach to `blk_mq_start_request` given that `blk_start_request` does not exist anymore.
weibang6liu · Aug 31, 2022 · 7f07581 · 7f07581
1 parent e56fdf8
commit 7f07581
Showing 1 changed file with 1 addition and 2 deletions.
diff --git a/tools/biosnoop.py b/tools/biosnoop.py
@@ -209,8 +209,7 @@
  b.attach_kprobe(event="blk_account_io_start", fn_name="trace_pid_start")
 if BPF.get_kprobe_functions(b'blk_start_request'):
  b.attach_kprobe(event="blk_start_request", fn_name="trace_req_start")
-else:
- b.attach_kprobe(event="blk_mq_start_request", fn_name="trace_req_start")
+b.attach_kprobe(event="blk_mq_start_request", fn_name="trace_req_start")
 if BPF.get_kprobe_functions(b'__blk_account_io_done'):
  b.attach_kprobe(event="__blk_account_io_done", fn_name="trace_req_completion")
 else: