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author | Lukas Wunner <lukas@wunner.de> | 2016-10-28 10:52:06 +0200 |
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committer | Bjorn Helgaas <bhelgaas@google.com> | 2016-11-17 18:44:56 -0600 |
commit | 1ed276a7b9d84626e5243fc54863440c74a4100a (patch) | |
tree | 6fa65a3a3c7125f6574f25bf37576b29f373f3ab /block/elevator.c | |
parent | 738a7edbfc7b623e276686dead046c9f3aae6b2e (diff) | |
download | linux-1ed276a7b9d84626e5243fc54863440c74a4100a.tar.bz2 |
PCI: Autosense device removal in pci_bridge_d3_update()
The algorithm to update the flag indicating whether a bridge may go to D3
makes a few optimizations based on whether the update was caused by the
removal of a device on the one hand, versus the addition of a device or the
change of its D3cold flags on the other hand.
The information whether the update pertains to a removal is currently
passed in by the caller, but the function may as well determine that itself
by examining the device in question, thereby allowing for a considerable
simplification and reduction of the code.
Out of several options to determine removal, I've chosen the function
device_is_registered() because it's cheap: It merely returns the
dev->kobj.state_in_sysfs flag. That flag is set through device_add() when
the root bus is scanned and cleared through device_remove(). The call to
pci_bridge_d3_update() happens after each of these calls, respectively, so
the ordering is correct.
No functional change intended.
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'block/elevator.c')
0 files changed, 0 insertions, 0 deletions