diff mbox series

[net,1/8] net/mlx5: HWS, removed wrong access to a number of rules variable

Message ID 20241015093208.197603-2-tariqt@nvidia.com (mailing list archive)
State Accepted
Commit 65b4eb9f3d1e037100b157e023f4d3d988aafd29
Delegated to: Netdev Maintainers
Headers show
Series mlx5 misc fixes 2024-10-15 | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5 this patch: 5
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 2 maintainers not CCed: andrew+netdev@lunn.ch linux-rdma@vger.kernel.org
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 4 this patch: 4
netdev/checkpatch warning WARNING: line length of 88 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Tariq Toukan Oct. 15, 2024, 9:32 a.m. UTC 
From: Yevgeny Kliteynik <kliteyn@nvidia.com>

Removed wrong access to the num_of_rules field of the matcher.
This is a usual u32 variable, but the access was as if it was atomic.

This fixes the following CI warnings:
  mlx5hws_bwc.c:708:17: warning: large atomic operation may incur significant performance penalty;
  the access size (4 bytes) exceeds the max lock-free size (0 bytes) [-Watomic-alignment]

Fixes: 510f9f61a112 ("net/mlx5: HWS, added API and enabled HWS support")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202409291101.6NdtMFVC-lkp@intel.com/
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Itamar Gozlan <igozlan@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 .../ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_bwc.c    | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_bwc.c b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_bwc.c
index bd52b05db367..8f3a6f9d703d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_bwc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_bwc.c
@@ -691,7 +691,6 @@  static int hws_bwc_matcher_move(struct mlx5hws_bwc_matcher *bwc_matcher)
 static int
 hws_bwc_matcher_rehash_size(struct mlx5hws_bwc_matcher *bwc_matcher)
 {
-	u32 num_of_rules;
 	int ret;
 
 	/* If the current matcher size is already at its max size, we can't
@@ -705,8 +704,7 @@  hws_bwc_matcher_rehash_size(struct mlx5hws_bwc_matcher *bwc_matcher)
 	 * Need to check again if we really need rehash.
 	 * If the reason for rehash was size, but not any more - skip rehash.
 	 */
-	num_of_rules = __atomic_load_n(&bwc_matcher->num_of_rules, __ATOMIC_RELAXED);
-	if (!hws_bwc_matcher_rehash_size_needed(bwc_matcher, num_of_rules))
+	if (!hws_bwc_matcher_rehash_size_needed(bwc_matcher, bwc_matcher->num_of_rules))
 		return 0;
 
 	/* Now we're done all the checking - do the rehash: