Martin K. Petersen f8f91f3f31 scsi: libfc: Revert "[SCSI] libfc: use offload EM instance again instead jumping to next EM" ... This reverts commit 3e22760d4d. This revert came about because of efforts by Ewan Milne, Curtis Taylor and I. In researching this issue, significant performance issues were seen on large CPU count systems using the software FCOE stack. Hannes also weighed in. The same was not apparent on much smaller low count CPU systems. The behavior introduced by commit 3e22760d4d lands sup with large count CPU systems seeing continual blk_requeue_request() calls due to ML_QUEUE_HOST_BUSY. fc_exch_alloc() used to try all the available exchange managers in the list for an available exchange id, but this was changed in 2010 so that if the first matched exchange manager couldn't allocate one, it fails and we end up returning host busy. This was due to commit: Setting the ddp_min module parameter to fcoe to 128MB prevents the ->match function from permitting the use of the offload exchange manager for the frame, and we no longer see the problem with host busy status, since it uses the larger non-offloaded pool. Reverting commit 3e22760d4d was tested to also prevent the host busy issue due to failing allocations. Suggested-by: Ewan Milne <emilne@redhat.com> Suggested-by: Curtis Taylor <cjt@us.ibm.com> Tested-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Laurence Oberman <loberman@redhat.com>		2016-11-08 17:29:51 -05:00
..
fc_disc.c	scsi: libfc: Fixup disc_mutex handling	2016-11-08 17:29:46 -05:00
fc_elsct.c	[SCSI] libfc: Make the libfc Common Transport(CT) code generic	2012-02-19 08:08:58 -06:00
fc_exch.c	scsi: libfc: Revert "[SCSI] libfc: use offload EM instance again instead jumping to next EM"	2016-11-08 17:29:51 -05:00
fc_fcp.c	SCSI misc on 20150901	2015-09-02 12:22:54 -07:00
fc_frame.c	[SCSI] libfc, fcoe, bnx2fc: cleanup fcoe_dev_stats	2012-07-20 08:31:47 +01:00
fc_libfc.c	libfc: Replace rcu_assign_pointer() with RCU_INIT_POINTER()	2014-09-30 09:28:36 +02:00
fc_libfc.h	libfc, libfcoe, fcoe: Convert debug_logging macros to pr_info	2012-12-14 10:38:55 -08:00
fc_lport.c	scsi: libfc: Fixup disc_mutex handling	2016-11-08 17:29:46 -05:00
fc_npiv.c	libfc: Use the correct function name in kernel-doc comment.	2015-11-09 17:15:52 -08:00
fc_rport.c	scsi: libfc: don't advance state machine for incoming FLOGI	2016-11-08 17:29:47 -05:00
Makefile	[SCSI] libfc: add some generic NPIV support routines to libfc	2009-12-04 12:00:56 -06:00