Re: [PATCH] USB: serial: relax unthrottle memory barrier

From: Davidlohr Bueso
Date: Thu Jan 30 2020 - 10:43:39 EST


On Thu, 30 Jan 2020, Johan Hovold wrote:

Commit a8d78d9f3856 ("USB: serial: clean up throttle handling")
converted the throttle handling to use atomic bitops. This means that we
can relax the smp_mb() in unthrottle() to smp_mb__after_atomic(), which
for example is a no-op on architectures like x86 that provide fully
ordered atomics.

Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>

Reviewed-by: Davidlohr Bueso <dbueso@xxxxxxx>