driver core: Don't require dynamic_debug for initcall_debug probe timing

Don't require the use of dynamic debug (or modification of the kernel to
add a #define DEBUG to the top of this file) to get the printk message
about driver probe timing. This printk is only emitted when
initcall_debug is enabled on the kernel commandline, and it isn't
immediately obvious that you have to do something else to debug boot
timing issues related to driver probe. Add a comment too so it doesn't
get converted back to pr_debug().

Fixes: eb7fbc9fb1 ("driver core: Add missing '\n' in log messages")
Cc: stable <stable@kernel.org>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Brian Norris <briannorris@chromium.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20230412225842.3196599-1-swboyd@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Stephen Boyd 2023-04-12 15:58:42 -07:00 committed by Greg Kroah-Hartman
parent bedee105bf
commit e2f06aa885
1 changed files with 6 additions and 1 deletions

View File

@ -735,7 +735,12 @@ static int really_probe_debug(struct device *dev, struct device_driver *drv)
calltime = ktime_get();
ret = really_probe(dev, drv);
rettime = ktime_get();
pr_debug("probe of %s returned %d after %lld usecs\n",
/*
* Don't change this to pr_debug() because that requires
* CONFIG_DYNAMIC_DEBUG and we want a simple 'initcall_debug' on the
* kernel commandline to print this all the time at the debug level.
*/
printk(KERN_DEBUG "probe of %s returned %d after %lld usecs\n",
dev_name(dev), ret, ktime_us_delta(rettime, calltime));
return ret;
}