On Mon, 2022-11-28 at 10:24 -0500, Steven Rostedt wrote:
> On Mon, 28 Nov 2022 14:21:06 +0100
>
> Bean Huo <beanhuo@xxxxxxxx> wrote:
>
>
>
> > From: Bean Huo <beanhuo@xxxxxxxxxx>
> > If it eventually mounts successfully, it should return 1 instead of
> > 0, otherwise it will make the caller's verification logic more
> > complicated
>
>
> The man page shows:
>
>
>
> The tracefs_tracing_dir_is_mounted() returns 1 if the tracing
> directory is
>
> already mounted, 0 if it is not, and -1 on error.
>
>
>
> If you only want to mount it and not care if it was already mounted
> then
>
> use tracefs_tracing_dir(), as it will return the path of the mount
> point
>
> and try to mount it if it is not already, or NULL if it could not
> mount it.
>
>
>
Hi Steve,
I used to reply on tracefs_tracing_dir(). But after updated the
libtracefs yesterday, I found my app doesn't work as before, then
checked the changelog, and switch to use
tracefs_tracing_dir_is_mounted.
in your latest libtracefs:
const char *tracefs_tracing_dir(void) {
...
tracing_dir = trace_find_tracing_dir(false);//shold be changed to true?
...
}
__hidden char *trace_find_tracing_dir(bool debugfs)
{
return find_tracing_dir(debugfs, false);
}
static char *find_tracing_dir(bool debugfs, bool mount) {
...
if (!mount || mount_debugfs() < 0)
return NULL;
...
}
Kind regards,
Bean
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