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| author | Ming Lei <tom.leiming@gmail.com> | 2009-01-21 16:27:47 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-03-25 00:38:24 +0100 |
| commit | 49b420a13ff95b449947181190b08367348e3e1b (patch) | |
| tree | 5feec1d1eac071e46c9aacec4255d891fa4f7ed2 /drivers/base/bus.c | |
| parent | sysfs: Take sysfs_mutex when fetching the root inode. (diff) | |
| download | linux-49b420a13ff95b449947181190b08367348e3e1b.tar.xz linux-49b420a13ff95b449947181190b08367348e3e1b.zip | |
driver core: check bus->match without holding device lock
This patch moves bus->match out from driver_probe_device and
does not hold device lock to check the match between a device
and a driver.
The idea has been verified by the commit 6cd495860901,
which leads to a faster boot. But the commit 6cd495860901 has
the following drawbacks: 1),only does the quick check in
the path of __driver_attach->driver_probe_device, not in other
paths; 2),for a matched device and driver, check the same match
twice. It is a waste of cpu ,especially for some drivers with long
device id table (eg. usb-storage driver).
This patch adds a helper of driver_match_device to check the match
in all paths, and testes the match only once.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/base/bus.c')
| -rw-r--r-- | drivers/base/bus.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 83f32b891fa9..8547b780bb5a 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -198,7 +198,7 @@ static ssize_t driver_bind(struct device_driver *drv, int err = -ENODEV; dev = bus_find_device_by_name(bus, NULL, buf); - if (dev && dev->driver == NULL) { + if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { if (dev->parent) /* Needed for USB */ down(&dev->parent->sem); down(&dev->sem); |