rds/ib: decrement ib_rx_total_incs after releasing associated cache

rds_ib_cache_gc_worker() runs periodically and releases unused receive
cache entries ('incs', 'frags') from all the CPUs. Currently, RDS does not
decrease ib_rx_total_incs counter after freeing 'incs' cache. This makes
the counter to report hugh value over time. This patch fixes it by
decrementing the counter after free.

Orabug: 36760266

Fixes: 8450b32 ("RDS-IB: Add garbage-collection to cache")
Reported-by: Rama Nichanamatlu <[email protected]>
Signed-off-by: Arumugam Kolappan <[email protected]>
Reviewed-by: Håkon Bugge <[email protected]>
Signed-off-by: Vijayendra Suman <[email protected]>

Author: Arumugam Kolappan

net/rds/ib.c

@@ -387,6 +387,7 @@ void rds_ib_free_one_inc(struct rds_ib_incoming *inc)
 	inc->ii_cache_entry.next = 0;
 	WARN_ON(!list_empty(&inc->ii_frags));
 	kmem_cache_free(rds_ib_incoming_slab, inc);
+	rds_ib_stats_dec(s_ib_rx_total_incs);
 }
 
 static void rds_ib_free_inc_cache_one(struct rds_ib_refill_cache *cache, int cpu)