[SCSI] fcoe, libfc: fully makes use of per cpu exch pool and then removes em_lock
1. Updates fcoe_rcv() to queue incoming frames to the fcoe per
cpu thread on which this frame's exch was originated and simply
use current cpu for request exch not originated by initiator.
It is redundant to add this code under CONFIG_SMP, so removes
CONFIG_SMP uses around this code.
2. Updates fc_exch_em_alloc, fc_exch_delete, fc_exch_find to use
per cpu exch pools, here fc_exch_delete is rename of older
fc_exch_mgr_delete_ep since ep/exch are now deleted in pools
of EM and so brief new name is sufficient and better name.
Updates these functions to map exch id to their index into exch
pool using fc_cpu_mask, fc_cpu_order and EM min_xid.
This mapping is as per detailed explanation about this in
last patch and basically this is just as lower fc_cpu_mask
bits of exch id as cpu number and upper bit sum of EM min_xid
and exch index in pool.
Uses pool next_index to keep track of exch allocation from
pool along with pool_max_index as upper bound of exches array
in pool.
3. Adds exch pool ptr to fc_exch to free exch to its pool in
fc_exch_delete.
4. Updates fc_exch_mgr_reset to reset all exch pools of an EM,
this required adding fc_exch_pool_reset func to reset exches
in pool and then have fc_exch_mgr_reset call fc_exch_pool_reset
for each pool within each EM for a lport.
5. Removes no longer needed exches array, em_lock, next_xid, and
total_exches from struct fc_exch_mgr, these are not needed after
use of per cpu exch pool, also removes not used max_read,
last_read from struct fc_exch_mgr.
6. Updates locking notes for exch pool lock with fc_exch lock and
uses pool lock in exch allocation, lookup and reset.
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h
index 3206338..53b3881 100644
--- a/include/scsi/libfc.h
+++ b/include/scsi/libfc.h
@@ -368,6 +368,7 @@
*/
struct fc_exch {
struct fc_exch_mgr *em; /* exchange manager */
+ struct fc_exch_pool *pool; /* per cpu exches pool */
u32 state; /* internal driver state */
u16 xid; /* our exchange ID */
struct list_head ex_list; /* free or busy list linkage */
@@ -1045,10 +1046,12 @@
*/
struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
+
/*
- * Reset an exchange manager, completing all sequences and exchanges.
- * If s_id is non-zero, reset only exchanges originating from that FID.
- * If d_id is non-zero, reset only exchanges sending to that FID.
+ * Reset all EMs of a lport, releasing its all sequences and
+ * exchanges. If sid is non-zero, then reset only exchanges
+ * we sourced from that FID. If did is non-zero, reset only
+ * exchanges destined to that FID.
*/
void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);