[dpdk-dev] [PATCH] hash: fix array out of bounds in hash library

[dpdk-dev] [PATCH] hash: fix array out of bounds in hash library

[Pablo de Lara]

When encountering a loop while adding a new entry,
element out of bounds of array was being unnecessarily resetted.

Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
---
 lib/librte_hash/rte_cuckoo_hash.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
index 93f94a5..b753e77 100644
--- a/lib/librte_hash/rte_cuckoo_hash.c
+++ b/lib/librte_hash/rte_cuckoo_hash.c
@@ -446,11 +446,8 @@ make_space_bucket(const struct rte_hash *h, struct rte_hash_bucket *bkt)
 			break;
 
 	/* All entries have been pushed, so entry cannot be added */
-	if (i == RTE_HASH_BUCKET_ENTRIES) {
-		/* Reset flag */
-		bkt->flag[i] = 0;
+	if (i == RTE_HASH_BUCKET_ENTRIES)
 		return -ENOSPC;
-	}
 
 	/* Set flag to indicate that this entry is going to be pushed */
 	bkt->flag[i] = 1;
-- 
2.4.2

[dpdk-dev] [PATCH] hash: fix compilation for gcc 4.4/4.5

[Pablo de Lara]

gcc 4.4 and 4.5 throws following error:
rte_cuckoo_hash.c:145: error: flexible array member in otherwise empty struct.

This is due to empty length in flexible array, which has been changed to use
size 0 in the declaration of the array.

Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")

Reported-by: Olga Shern <olgas@mellanox.com>
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
---
 lib/librte_hash/rte_cuckoo_hash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
index 39cafb7..80cb126 100644
--- a/lib/librte_hash/rte_cuckoo_hash.c
+++ b/lib/librte_hash/rte_cuckoo_hash.c
@@ -142,7 +142,7 @@ struct rte_hash_key {
 		void *pdata;
 	};
 	/* Variable key size */
-	char key[];
+	char key[0];
 } __attribute__((aligned(KEY_ALIGNMENT)));
 
 /** Bucket structure */
-- 
2.4.2

Re: [dpdk-dev] [PATCH] hash: fix compilation for gcc 4.4/4.5

[Thomas Monjalon]

2015-07-15 13:40, Pablo de Lara:
> gcc 4.4 and 4.5 throws following error:
> rte_cuckoo_hash.c:145: error: flexible array member in otherwise empty struct.
> 
> This is due to empty length in flexible array, which has been changed to use
> size 0 in the declaration of the array.
> 
> Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")
> 
> Reported-by: Olga Shern <olgas@mellanox.com>
> Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>

Applied, thanks

[dpdk-dev] [PATCH] hash: fix library compilation for CPU with no SSE4.1

[Pablo de Lara]

_mm_test_all_zeros is not available for CPUs with no SSE4.1,
therefore, DPDK would not build.
This patch adds an alternative for this, using _mm_cmpeq_epi32 and
_mm_movemask_epi8.

Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
---
 lib/librte_hash/rte_cuckoo_hash.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
index 80cb126..0f33376 100644
--- a/lib/librte_hash/rte_cuckoo_hash.c
+++ b/lib/librte_hash/rte_cuckoo_hash.c
@@ -1128,9 +1128,15 @@ rte_hash_k16_cmp_eq(const void *key1, const void *key2, size_t key_len __rte_unu
 {
 	const __m128i k1 = _mm_loadu_si128((const __m128i *) key1);
 	const __m128i k2 = _mm_loadu_si128((const __m128i *) key2);
+#ifndef RTE_MACHINE_CPUFLAG_SSE4_1
 	const __m128i x = _mm_xor_si128(k1, k2);
 
 	return !_mm_test_all_zeros(x, x);
+#else
+	const __m128i x = _mm_cmpeq_epi32(k1, k2);
+
+	return (_mm_movemask_epi8(x) != 0xffff);
+#endif
 }
 
 static int
-- 
2.4.2

Re: [dpdk-dev] [PATCH] hash: fix array out of bounds in hash library

[Thomas Monjalon]

2015-07-15 13:40, Pablo de Lara:
> When encountering a loop while adding a new entry,
> element out of bounds of array was being unnecessarily resetted.
> 
> Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")
> 
> Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>

Applied, thanks