Re: [PATCH v1 2/3] driver core: Read atomic counter once in driver_probe_done()

From: Ferry Toth
Date: Wed Mar 18 2020 - 20:06:07 EST


Op 09-03-2020 om 15:11 schreef Andy Shevchenko:
Between printing the debug message and actual check atomic counter can be
altered. For better debugging experience read atomic counter value only once.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

Tested-by: Ferry Toth <fntoth@xxxxxxxxx>

---
drivers/base/dd.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 43720beb5300..efd0e4c16ba5 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -669,9 +669,10 @@ static int really_probe_debug(struct device *dev, struct device_driver *drv)
*/
int driver_probe_done(void)
{
- pr_debug("%s: probe_count = %d\n", __func__,
- atomic_read(&probe_count));
- if (atomic_read(&probe_count))
+ int local_probe_count = atomic_read(&probe_count);
+
+ pr_debug("%s: probe_count = %d\n", __func__, local_probe_count);
+ if (local_probe_count)
return -EBUSY;
return 0;
}