On Mon, 22 Jan 2024 10:57:00 -0500 Steven Rostedt <[email protected]> wrote:
> On Mon, 22 Jan 2024 15:36:29 +0800 > George Guo <[email protected]> wrote: > > > From: George Guo <[email protected]> > > > > Add do_warn, warn_limit fields to the output of the > > percpu_alloc_percpu_fail ftrace event. > > > > This is required to percpu_alloc failed with no warning showing. > > You mean to state; > > In order to know why percpu_alloc failed but produces no warnings, > the do_warn and warn_limit should be traced to let the user know it > was rate-limited. > > Or something like that? > > Honestly, I don't think that the trace event is the proper place to do > that. The trace event just shows that it did fail. If you are > confused to why it doesn't print to dmesg, then you can simply add a > kprobe to see those values as well. > > -- Steve > > > > > Signed-off-by: George Guo <[email protected]> > > --- There are two reasons of percpu_alloc failed without warnings: 1. do_warn is false 2. do_warn is true and warn_limit is reached the limit. Showing do_warn and warn_limit makes things simple, maybe dont need kprobe again.
