From: Eric Dumazet <edumazet@google.com>
Date: Wed, 30 Oct 2019 11:48:44 -0700
Subject: dma-debug: increase HASH_SIZE
Git-commit: 5e76f564572b85735de4b75a5e73b514be2562be
Patch-mainline: v5.5-rc1
References: bsc#1175713
With modern NIC, it is not unusual having about ~256,000 active dma
mappings and a hash size of 1024 buckets is too small.
Forcing full cache line per bucket does not seem useful, especially now
that we have contention on free_entries_lock for allocations and freeing
of entries. Better use the space to fit more buckets.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
kernel/dma/debug.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index a5b85dabfb8c..004496654aaa 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -27,7 +27,7 @@
#include <asm/sections.h>
-#define HASH_SIZE 1024ULL
+#define HASH_SIZE 16384ULL
#define HASH_FN_SHIFT 13
#define HASH_FN_MASK (HASH_SIZE - 1)
@@ -87,7 +87,7 @@ typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *);
struct hash_bucket {
struct list_head list;
spinlock_t lock;
-} ____cacheline_aligned_in_smp;
+};
/* Hash list to save the allocated dma addresses */
static struct hash_bucket dma_entry_hash[HASH_SIZE];