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6cd4958609
This patch adds a quick check for the driver<->device match before taking the locks and doin gthe expensive checks. Taking the lock hurts in asynchronous boot context where the device lock gets hit; one of the init functions takes the lock and goes to do an expensive hardware init; the other init functions walk the same PCI list and get stuck on the lock as a result. For the common case, we can know there's no chance whatsoever of a match if the device isn't in the drivers ID table... so this patch does that check as a best-effort-avoid-the-lock approach. Bootcharts for before and after can be seen at http://www.fenrus.org/before.svg http://www.fenrus.org/after.svg Note the long time "agp_ali_init" takes in the first graph; my laptop doesn't even have an ALI chip in it! (the bootgraphs look a bit dissimilar, but that's the point, the first one has a bunch of arbitrary delays in it that cause it to look very different) This reduces my kernel boot time by about 20% Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
367 lines
9 KiB
367 lines
9 KiB