PM / devfreq: bw_hwmon: Fix race condition in polling interval update
When the polling interval is updated, the delayed workqueue is cancelled
and requeued with the new polling interval. However, the bw_hwmon IRQ can
come at the same time and try to stop and restart the delayed work (in the
IRQ thread). This can cause a race where the work might be queued twice or
canceled twice and cause a crash.
Fix this race condition by suspending and resuming the HW monitor when we
are updating the polling interval. This entirely avoids the race because
suspending the HW monitor also avoid the possibility of the IRQ coming
during the polling interval update.
CRs-Fixed: 954082
Change-Id: Ic7baf2a3da4ed8f8a9023617059e22fd81c3ba45
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
1 file changed