diff options
| author | Bart Van Assche <bvanassche@acm.org> | 2013-08-14 15:38:24 +0000 |
|---|---|---|
| committer | Robert Love <robert.w.love@intel.com> | 2013-09-04 13:37:53 -0700 |
| commit | f95b35cfcacadac16dbc5477fd22b0786256a3d1 (patch) | |
| tree | 18441baa204e00aa8327c71408a2a3bd9df96d46 /drivers | |
| parent | cae7b6dd6c569f18f5c8e3f33cac60fbaeb58140 (diff) | |
| download | op-kernel-dev-f95b35cfcacadac16dbc5477fd22b0786256a3d1.zip op-kernel-dev-f95b35cfcacadac16dbc5477fd22b0786256a3d1.tar.gz | |
libfc: Reduce exchange lock contention in fc_exch_recv_abts()
Reduce the time during which the exchange lock is held by allocating
a frame before obtaining the exchange lock.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/scsi/libfc/fc_exch.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c index 2a7fd5a..47ebc7b 100644 --- a/drivers/scsi/libfc/fc_exch.c +++ b/drivers/scsi/libfc/fc_exch.c @@ -1307,9 +1307,16 @@ static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp) if (!ep) goto reject; + + fp = fc_frame_alloc(ep->lp, sizeof(*ap)); + if (!fp) + goto free; + spin_lock_bh(&ep->ex_lock); if (ep->esb_stat & ESB_ST_COMPLETE) { spin_unlock_bh(&ep->ex_lock); + + fc_frame_free(fp); goto reject; } if (!(ep->esb_stat & ESB_ST_REC_QUAL)) { @@ -1317,12 +1324,6 @@ static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp) fc_exch_hold(ep); /* hold for REC_QUAL */ } fc_exch_timer_set_locked(ep, ep->r_a_tov); - - fp = fc_frame_alloc(ep->lp, sizeof(*ap)); - if (!fp) { - spin_unlock_bh(&ep->ex_lock); - goto free; - } fh = fc_frame_header_get(fp); ap = fc_frame_payload_get(fp, sizeof(*ap)); memset(ap, 0, sizeof(*ap)); @@ -1338,13 +1339,14 @@ static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp) fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS); ep->esb_stat |= ESB_ST_ABNORMAL; spin_unlock_bh(&ep->ex_lock); + +free: fc_frame_free(rx_fp); return; reject: fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID); -free: - fc_frame_free(rx_fp); + goto free; } /** |
