Re: Interface for enabling context tracking

[Steven Rostedt]

On Thu, 17 Apr 2025 14:10:53 -0500
Junxuan Liao <ljx@xxxxxxxxxxx> wrote:

> Just found out that the exit tracepoints for syscalls aren't always
> exactly preceding the exit to userspace. The kernel can still spend
> quite some time in task_work_run after the tracepoints are triggered.
> Has that bothered you before?

It's been a while, but what I usually do when I want to see entry into the
kernel is also to run:

  trace-cmd set -p function_graph --max-graph-depth 1

Which tracks the first function call into the kernel. It obviously now
misses entry and exit from user mode due to noinstr, but if a task_work
function is called, it will usually catch that too.

-- Steve