[PATCH v5 0/3] multi-threading device shutdown
- Date: Tue, 15 May 2018 22:40:01 -0400
- From: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
- Subject: [PATCH v5 0/3] multi-threading device shutdown
v4 - v5
- Addressed comments from Andy Shevchenko and Greg
- Split the patch into a series of 3 patches in order to
provide a better bisecting, and facilitate with reviewing.
v3 - v4
- Added device_shutdown_serial kernel parameter to disable
multi-threading as suggested by Greg Kroah-Hartman
v2 - v3
- Fixed warning from kbuild test.
- Moved device_lock/device_unlock inside device_shutdown_tree().
v1 - v2
- It turns out we cannot lock more than MAX_LOCK_DEPTH by a single
thread. (By default this value is 48), and is used to detect
deadlocks. So, I re-wrote the code to only lock one devices per
thread instead of pre-locking all devices by the main thread.
- Addressed comments from Tobin C. Harding.
- As suggested by Alexander Duyck removed ixgbe changes. It can be
done as a separate work scaling RTNL mutex.
Do a faster shutdown by calling dev->*->shutdown(dev) in parallel.
device_shutdown() calls these functions for every single device but
only using one thread.
Since, nothing else is running on the machine by the time
device_shutdown() is called, there is no reason not to utilize all the
available CPU resources.
Pavel Tatashin (3):
drivers core: refactor device_shutdown
drivers core: prepare device_shutdown for multi-threading
drivers core: multi-threading device shutdown
drivers/base/core.c | 290 +++++++++++++++++++++++++++++++++++++-------
1 file changed, 243 insertions(+), 47 deletions(-)