From: Chris Leech Date: Thu, 10 Dec 2009 17:59:26 +0000 (-0800) Subject: [SCSI] libfc: reduce hold time on SCSI host lock X-Git-Tag: v2.6.33-rc1~5^2~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c1ecb90a66c5afc7cc5c9349f9c3714eef4a5cfb;p=pandora-kernel.git [SCSI] libfc: reduce hold time on SCSI host lock Introduce a new lock to protect the list of fc_fcp_pkt structs in libfc instead of using the host lock. This reduces the contention of this heavily used lock, and I see up to a 25% performance gain in CPU bound small I/O tests when scaling out across multiple quad-core CPUs. The big win is in removing the host lock from the completion path completely, as it does not need to be held around the call to scsi_done. Signed-off-by: Chris Leech Signed-off-by: Robert Love Signed-off-by: James Bottomley --- Reading git-diff-tree failed