[PATCH] wifi: mac80211: clean up assignments to pointer cache.

[PATCH] wifi: mac80211: clean up assignments to pointer cache.

[Colin Ian King]

From: Colin Ian King <colin.i.king@intel.com>

The assignment to pointer cache in function mesh_fast_tx_gc can
be made at the declaration time rather than a later assignment.
There are also 3 functions where pointer cache is being initialized
at declaration time and later re-assigned again with the same
value, these are redundant and can be removed.

Cleans up code and three clang scan build warnings:
warning: Value stored to 'cache' during its initialization is never
read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@intel.com>
---
 net/mac80211/mesh_pathtbl.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index 735edde1bd81..91b55d6a68b9 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -599,13 +599,12 @@ void mesh_fast_tx_cache(struct ieee80211_sub_if_data *sdata,
 
 void mesh_fast_tx_gc(struct ieee80211_sub_if_data *sdata)
 {
 	unsigned long timeout = msecs_to_jiffies(MESH_FAST_TX_CACHE_TIMEOUT);
-	struct mesh_tx_cache *cache;
+	struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
 	struct ieee80211_mesh_fast_tx *entry;
 	struct hlist_node *n;
 
-	cache = &sdata->u.mesh.tx_cache;
 	if (atomic_read(&cache->rht.nelems) < MESH_FAST_TX_CACHE_THRESHOLD_SIZE)
 		return;
 
 	spin_lock_bh(&cache->walk_lock);
@@ -621,9 +620,8 @@ void mesh_fast_tx_flush_mpath(struct mesh_path *mpath)
 	struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
 	struct ieee80211_mesh_fast_tx *entry;
 	struct hlist_node *n;
 
-	cache = &sdata->u.mesh.tx_cache;
 	spin_lock_bh(&cache->walk_lock);
 	hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
 		if (entry->mpath == mpath)
 			mesh_fast_tx_entry_free(cache, entry);
@@ -636,9 +634,8 @@ void mesh_fast_tx_flush_sta(struct ieee80211_sub_if_data *sdata,
 	struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
 	struct ieee80211_mesh_fast_tx *entry;
 	struct hlist_node *n;
 
-	cache = &sdata->u.mesh.tx_cache;
 	spin_lock_bh(&cache->walk_lock);
 	hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
 		if (rcu_access_pointer(entry->mpath->next_hop) == sta)
 			mesh_fast_tx_entry_free(cache, entry);
@@ -650,9 +647,8 @@ void mesh_fast_tx_flush_addr(struct ieee80211_sub_if_data *sdata,
 {
 	struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
 	struct ieee80211_mesh_fast_tx *entry;
 
-	cache = &sdata->u.mesh.tx_cache;
 	spin_lock_bh(&cache->walk_lock);
 	entry = rhashtable_lookup_fast(&cache->rht, addr, fast_tx_rht_params);
 	if (entry)
 		mesh_fast_tx_entry_free(cache, entry);
-- 
2.43.0

Re: [PATCH] wifi: mac80211: clean up assignments to pointer cache.

[Simon Horman]

On Thu, Feb 15, 2024 at 11:21:51PM +0000, Colin Ian King wrote:
> From: Colin Ian King <colin.i.king@intel.com>
> 
> The assignment to pointer cache in function mesh_fast_tx_gc can
> be made at the declaration time rather than a later assignment.
> There are also 3 functions where pointer cache is being initialized
> at declaration time and later re-assigned again with the same
> value, these are redundant and can be removed.
> 
> Cleans up code and three clang scan build warnings:
> warning: Value stored to 'cache' during its initialization is never
> read [deadcode.DeadStores]
> 
> Signed-off-by: Colin Ian King <colin.i.king@intel.com>

FWIIW, these changes look fine to me although I might have split the
mesh_fast_tx_gc() and mesh_fast_tx_flush_sta() changes into different
patches as they seem to address separate issues.

That notwithstanding,

Reviewed-by: Simon Horman <horms@kernel.org>