diff mbox series

net/bnxt: fix doorbell barrier location

Message ID 20201113160445.365550-1-lance.richardson@broadcom.com (mailing list archive)
State Accepted, archived
Delegated to: Ferruh Yigit
Headers
Series net/bnxt: fix doorbell barrier location |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/iol-broadcom-Performance success Performance Testing PASS
ci/iol-broadcom-Functional success Functional Testing PASS
ci/iol-testing success Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/travis-robot success Travis build: passed
ci/iol-mellanox-Performance success Performance Testing PASS
ci/Intel-compilation success Compilation OK

Commit Message

Lance Richardson Nov. 13, 2020, 4:04 p.m. UTC 
  Simplify some doorbell functions now that rte_cio_wmb() has been
eliminated and rte_io_wmb() is equivalent for Arm.

Fix a performance degradation on x86 platforms caused by a
previous Arm performance fix by moving the compiler barrier
closer to the I/O write.

Fixes: f0f5d844d138 ("eal: remove deprecated coherent IO memory barriers")
Fixes: bfc1d45875e2 ("net/bnxt: fix performance for Arm")
Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
---
 drivers/net/bnxt/bnxt_ring.h | 37 +++++++++++++++++++-----------------
 1 file changed, 20 insertions(+), 17 deletions(-)

Comments

Ferruh Yigit Nov. 13, 2020, 5:38 p.m. UTC | #1 
On 11/13/2020 4:04 PM, Lance Richardson wrote:
> Simplify some doorbell functions now that rte_cio_wmb() has been
> eliminated and rte_io_wmb() is equivalent for Arm.
> 
> Fix a performance degradation on x86 platforms caused by a
> previous Arm performance fix by moving the compiler barrier
> closer to the I/O write.
> 
> Fixes: f0f5d844d138 ("eal: remove deprecated coherent IO memory barriers")
> Fixes: bfc1d45875e2 ("net/bnxt: fix performance for Arm")
> Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
> Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>

Applied to dpdk-next-net/main, thanks.
diff mbox series

Patch

diff --git a/drivers/net/bnxt/bnxt_ring.h b/drivers/net/bnxt/bnxt_ring.h
index 3d81f610c..0a4685d16 100644
--- a/drivers/net/bnxt/bnxt_ring.h
+++ b/drivers/net/bnxt/bnxt_ring.h
@@ -82,12 +82,10 @@  void bnxt_free_rxtx_nq_ring(struct bnxt *bp);
 
 static inline void bnxt_db_write(struct bnxt_db_info *db, uint32_t idx)
 {
-	rte_io_wmb();
-
 	if (db->db_64)
-		rte_write64_relaxed(db->db_key64 | idx, db->doorbell);
+		rte_write64(db->db_key64 | idx, db->doorbell);
 	else
-		rte_write32_relaxed(db->db_key32 | idx, db->doorbell);
+		rte_write32(db->db_key32 | idx, db->doorbell);
 }
 
 /* Ring an NQ doorbell and disable interrupts for the ring. */
@@ -96,10 +94,9 @@  static inline void bnxt_db_nq(struct bnxt_cp_ring_info *cpr)
 	if (unlikely(!cpr->cp_db.db_64))
 		return;
 
-	rte_io_wmb();
-	rte_write64_relaxed(cpr->cp_db.db_key64 | DBR_TYPE_NQ |
-			    RING_CMP(cpr->cp_ring_struct, cpr->cp_raw_cons),
-			    cpr->cp_db.doorbell);
+	rte_write64(cpr->cp_db.db_key64 | DBR_TYPE_NQ |
+		    RING_CMP(cpr->cp_ring_struct, cpr->cp_raw_cons),
+		    cpr->cp_db.doorbell);
 }
 
 /* Ring an NQ doorbell and enable interrupts for the ring. */
@@ -108,10 +105,9 @@  static inline void bnxt_db_nq_arm(struct bnxt_cp_ring_info *cpr)
 	if (unlikely(!cpr->cp_db.db_64))
 		return;
 
-	rte_io_wmb();
-	rte_write64_relaxed(cpr->cp_db.db_key64 | DBR_TYPE_NQ_ARM |
-			    RING_CMP(cpr->cp_ring_struct, cpr->cp_raw_cons),
-			    cpr->cp_db.doorbell);
+	rte_write64(cpr->cp_db.db_key64 | DBR_TYPE_NQ_ARM |
+		    RING_CMP(cpr->cp_ring_struct, cpr->cp_raw_cons),
+		    cpr->cp_db.doorbell);
 }
 
 static inline void bnxt_db_cq(struct bnxt_cp_ring_info *cpr)
@@ -119,11 +115,18 @@  static inline void bnxt_db_cq(struct bnxt_cp_ring_info *cpr)
 	struct bnxt_db_info *db = &cpr->cp_db;
 	uint32_t idx = RING_CMP(cpr->cp_ring_struct, cpr->cp_raw_cons);
 
-	rte_compiler_barrier();
-	if (db->db_64)
-		rte_write64_relaxed(db->db_key64 | idx, db->doorbell);
-	else
-		B_CP_DIS_DB(cpr, cpr->cp_raw_cons);
+	if (db->db_64) {
+		uint64_t key_idx = db->db_key64 | idx;
+		void *doorbell = db->doorbell;
+
+		rte_compiler_barrier();
+		rte_write64_relaxed(key_idx, doorbell);
+	} else {
+		uint32_t cp_raw_cons = cpr->cp_raw_cons;
+
+		rte_compiler_barrier();
+		B_CP_DIS_DB(cpr, cp_raw_cons);
+	}
 }
 
 #endif