[PATCH v2 15/17] drivers/common: use previous value atomic fetch operations

[Tyler Retzlaff]

Use __atomic_fetch_{add,and,or,sub,xor} instead of
__atomic_{add,and,or,sub,xor}_fetch when we have no interest in the
result of the operation.

Reduces unnecessary codegen that provided the result of the atomic
operation that was not used.

Change brings closer alignment with atomics available in C11 standard
and will reduce review effort when they are integrated.

Signed-off-by: Tyler Retzlaff <roretzla at linux.microsoft.com>
Acked-by: Morten Brørup <mb at smartsharesystems.com>
---
 drivers/common/cnxk/roc_nix_inl_dev.c   |  2 +-
 drivers/common/mlx5/mlx5_common_mr.c    |  2 +-
 drivers/common/mlx5/mlx5_common_utils.c | 10 +++++-----
 drivers/common/mlx5/mlx5_malloc.c       | 16 ++++++++--------
 4 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/common/cnxk/roc_nix_inl_dev.c b/drivers/common/cnxk/roc_nix_inl_dev.c
index 6f60961..45d6f62 100644
--- a/drivers/common/cnxk/roc_nix_inl_dev.c
+++ b/drivers/common/cnxk/roc_nix_inl_dev.c
@@ -741,7 +741,7 @@
 			inl_dev->work_cb(&tmp, sa, (port_id << 8) | 0x1);
 			__atomic_store_n(ring_base + tail_l + 1, 0ULL,
 					 __ATOMIC_RELAXED);
-			__atomic_add_fetch((uint32_t *)ring_base, 1,
+			__atomic_fetch_add((uint32_t *)ring_base, 1,
 					   __ATOMIC_ACQ_REL);
 		} else
 			plt_err("Invalid SA");
diff --git a/drivers/common/mlx5/mlx5_common_mr.c b/drivers/common/mlx5/mlx5_common_mr.c
index 0e1d243..9ebe398 100644
--- a/drivers/common/mlx5/mlx5_common_mr.c
+++ b/drivers/common/mlx5/mlx5_common_mr.c
@@ -1650,7 +1650,7 @@ struct mlx5_mempool_get_extmem_data {
 	unsigned int i;
 
 	for (i = 0; i < mpr->mrs_n; i++)
-		__atomic_add_fetch(&mpr->mrs[i].refcnt, 1, __ATOMIC_RELAXED);
+		__atomic_fetch_add(&mpr->mrs[i].refcnt, 1, __ATOMIC_RELAXED);
 }
 
 /**
diff --git a/drivers/common/mlx5/mlx5_common_utils.c b/drivers/common/mlx5/mlx5_common_utils.c
index 58d744b..915a317 100644
--- a/drivers/common/mlx5/mlx5_common_utils.c
+++ b/drivers/common/mlx5/mlx5_common_utils.c
@@ -217,7 +217,7 @@ struct mlx5_list_entry *
 		entry->lcore_idx = (uint32_t)lcore_index;
 		LIST_INSERT_HEAD(&l_inconst->cache[lcore_index]->h,
 				 entry, next);
-		__atomic_add_fetch(&l_inconst->count, 1, __ATOMIC_RELAXED);
+		__atomic_fetch_add(&l_inconst->count, 1, __ATOMIC_RELAXED);
 		DRV_LOG(DEBUG, "MLX5 list %s c%d entry %p new: %u.",
 			l_const->name, lcore_index,
 			(void *)entry, entry->ref_cnt);
@@ -254,7 +254,7 @@ struct mlx5_list_entry *
 	l_inconst->gen_cnt++;
 	rte_rwlock_write_unlock(&l_inconst->lock);
 	LIST_INSERT_HEAD(&l_inconst->cache[lcore_index]->h, local_entry, next);
-	__atomic_add_fetch(&l_inconst->count, 1, __ATOMIC_RELAXED);
+	__atomic_fetch_add(&l_inconst->count, 1, __ATOMIC_RELAXED);
 	DRV_LOG(DEBUG, "mlx5 list %s entry %p new: %u.", l_const->name,
 		(void *)entry, entry->ref_cnt);
 	return local_entry;
@@ -294,11 +294,11 @@ struct mlx5_list_entry *
 		else
 			l_const->cb_remove(l_const->ctx, entry);
 	} else {
-		__atomic_add_fetch(&l_inconst->cache[entry->lcore_idx]->inv_cnt,
+		__atomic_fetch_add(&l_inconst->cache[entry->lcore_idx]->inv_cnt,
 				   1, __ATOMIC_RELAXED);
 	}
 	if (!l_const->lcores_share) {
-		__atomic_sub_fetch(&l_inconst->count, 1, __ATOMIC_RELAXED);
+		__atomic_fetch_sub(&l_inconst->count, 1, __ATOMIC_RELAXED);
 		DRV_LOG(DEBUG, "mlx5 list %s entry %p removed.",
 			l_const->name, (void *)entry);
 		return 0;
@@ -310,7 +310,7 @@ struct mlx5_list_entry *
 		LIST_REMOVE(gentry, next);
 		rte_rwlock_write_unlock(&l_inconst->lock);
 		l_const->cb_remove(l_const->ctx, gentry);
-		__atomic_sub_fetch(&l_inconst->count, 1, __ATOMIC_RELAXED);
+		__atomic_fetch_sub(&l_inconst->count, 1, __ATOMIC_RELAXED);
 		DRV_LOG(DEBUG, "mlx5 list %s entry %p removed.",
 			l_const->name, (void *)gentry);
 		return 0;
diff --git a/drivers/common/mlx5/mlx5_malloc.c b/drivers/common/mlx5/mlx5_malloc.c
index cef3b88..c58c41d 100644
--- a/drivers/common/mlx5/mlx5_malloc.c
+++ b/drivers/common/mlx5/mlx5_malloc.c
@@ -99,7 +99,7 @@ struct mlx5_sys_mem {
 			rte_mem_virt2memseg_list(addr),
 			__ATOMIC_RELAXED);
 #ifdef RTE_LIBRTE_MLX5_DEBUG
-		__atomic_add_fetch(&mlx5_sys_mem.msl_update, 1,
+		__atomic_fetch_add(&mlx5_sys_mem.msl_update, 1,
 				   __ATOMIC_RELAXED);
 #endif
 	}
@@ -126,7 +126,7 @@ struct mlx5_sys_mem {
 		if (!rte_mem_virt2memseg_list(addr))
 			return false;
 #ifdef RTE_LIBRTE_MLX5_DEBUG
-		__atomic_add_fetch(&mlx5_sys_mem.msl_miss, 1, __ATOMIC_RELAXED);
+		__atomic_fetch_add(&mlx5_sys_mem.msl_miss, 1, __ATOMIC_RELAXED);
 #endif
 	}
 	return true;
@@ -185,7 +185,7 @@ struct mlx5_sys_mem {
 		mlx5_mem_update_msl(addr);
 #ifdef RTE_LIBRTE_MLX5_DEBUG
 		if (addr)
-			__atomic_add_fetch(&mlx5_sys_mem.malloc_rte, 1,
+			__atomic_fetch_add(&mlx5_sys_mem.malloc_rte, 1,
 					   __ATOMIC_RELAXED);
 #endif
 		return addr;
@@ -199,7 +199,7 @@ struct mlx5_sys_mem {
 		addr = malloc(size);
 #ifdef RTE_LIBRTE_MLX5_DEBUG
 	if (addr)
-		__atomic_add_fetch(&mlx5_sys_mem.malloc_sys, 1,
+		__atomic_fetch_add(&mlx5_sys_mem.malloc_sys, 1,
 				   __ATOMIC_RELAXED);
 #endif
 	return addr;
@@ -233,7 +233,7 @@ struct mlx5_sys_mem {
 		mlx5_mem_update_msl(new_addr);
 #ifdef RTE_LIBRTE_MLX5_DEBUG
 		if (new_addr)
-			__atomic_add_fetch(&mlx5_sys_mem.realloc_rte, 1,
+			__atomic_fetch_add(&mlx5_sys_mem.realloc_rte, 1,
 					   __ATOMIC_RELAXED);
 #endif
 		return new_addr;
@@ -246,7 +246,7 @@ struct mlx5_sys_mem {
 	new_addr = realloc(addr, size);
 #ifdef RTE_LIBRTE_MLX5_DEBUG
 	if (new_addr)
-		__atomic_add_fetch(&mlx5_sys_mem.realloc_sys, 1,
+		__atomic_fetch_add(&mlx5_sys_mem.realloc_sys, 1,
 				   __ATOMIC_RELAXED);
 #endif
 	return new_addr;
@@ -259,13 +259,13 @@ struct mlx5_sys_mem {
 		return;
 	if (!mlx5_mem_is_rte(addr)) {
 #ifdef RTE_LIBRTE_MLX5_DEBUG
-		__atomic_add_fetch(&mlx5_sys_mem.free_sys, 1,
+		__atomic_fetch_add(&mlx5_sys_mem.free_sys, 1,
 				   __ATOMIC_RELAXED);
 #endif
 		mlx5_os_free(addr);
 	} else {
 #ifdef RTE_LIBRTE_MLX5_DEBUG
-		__atomic_add_fetch(&mlx5_sys_mem.free_rte, 1,
+		__atomic_fetch_add(&mlx5_sys_mem.free_rte, 1,
 				   __ATOMIC_RELAXED);
 #endif
 		rte_free(addr);
-- 
1.8.3.1