From: Stephen Hemminger <stephen@networkplumber.org>
To: dev@dpdk.org
Cc: Stephen Hemminger <stephen@networkplumber.org>,
Konstantin Ananyev <konstantin.ananyev@huawei.com>
Subject: [PATCH v4 5/5] bpf: replace use of VLA
Date: Tue, 4 Nov 2025 08:07:30 -0800 [thread overview]
Message-ID: <20251104160843.304044-6-stephen@networkplumber.org> (raw)
In-Reply-To: <20251104160843.304044-1-stephen@networkplumber.org>
Variable length arrays are extension not required in C standard
and not available in Windows.
Use alloca() instead of variable length array.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
lib/bpf/bpf_pkt.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/lib/bpf/bpf_pkt.c b/lib/bpf/bpf_pkt.c
index 087ac0f244..5007f6aef5 100644
--- a/lib/bpf/bpf_pkt.c
+++ b/lib/bpf/bpf_pkt.c
@@ -163,7 +163,7 @@ apply_filter(struct rte_mbuf *mb[], const uint64_t rc[], uint32_t num,
uint32_t drop)
{
uint32_t i, j, k;
- struct rte_mbuf *dr[num];
+ struct rte_mbuf **dr = alloca(num * sizeof(struct rte_mbuf *));
for (i = 0, j = 0, k = 0; i != num; i++) {
@@ -192,8 +192,8 @@ pkt_filter_vm(const struct rte_bpf *bpf, struct rte_mbuf *mb[], uint32_t num,
uint32_t drop)
{
uint32_t i;
- void *dp[num];
- uint64_t rc[num];
+ void **dp = alloca(num * sizeof(void *));
+ uint64_t *rc = alloca(num * sizeof(uint64_t));
for (i = 0; i != num; i++)
dp[i] = rte_pktmbuf_mtod(mb[i], void *);
@@ -208,7 +208,7 @@ pkt_filter_jit(const struct rte_bpf_jit *jit, struct rte_mbuf *mb[],
{
uint32_t i, n;
void *dp;
- uint64_t rc[num];
+ uint64_t *rc = alloca(num * sizeof(uint64_t));
n = 0;
for (i = 0; i != num; i++) {
@@ -227,7 +227,7 @@ static inline uint32_t
pkt_filter_mb_vm(const struct rte_bpf *bpf, struct rte_mbuf *mb[], uint32_t num,
uint32_t drop)
{
- uint64_t rc[num];
+ uint64_t *rc = alloca(num * sizeof(uint64_t));
rte_bpf_exec_burst(bpf, (void **)mb, rc, num);
return apply_filter(mb, rc, num, drop);
@@ -238,7 +238,7 @@ pkt_filter_mb_jit(const struct rte_bpf_jit *jit, struct rte_mbuf *mb[],
uint32_t num, uint32_t drop)
{
uint32_t i, n;
- uint64_t rc[num];
+ uint64_t *rc = alloca(num * sizeof(uint64_t));
n = 0;
for (i = 0; i != num; i++) {
--
2.51.0
prev parent reply other threads:[~2025-11-04 16:09 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-30 17:34 [PATCH 0/5] bpf enhancements Stephen Hemminger
2025-10-30 17:34 ` [PATCH 1/5] bpf: add allocation annotations to functions Stephen Hemminger
2025-10-30 17:34 ` [PATCH 2/5] bpf: use rte_pktmbuf_free_bulk Stephen Hemminger
2025-10-30 17:34 ` [PATCH 3/5] bpf: add a test for BPF ELF load Stephen Hemminger
2025-10-30 17:34 ` [PATCH 4/5] bpf: add test for rx and tx filtering Stephen Hemminger
2025-10-30 17:34 ` [PATCH 5/5] bpf: remove use of vla Stephen Hemminger
2025-10-31 11:39 ` [PATCH 0/5] bpf enhancements Marat Khalili
2025-10-31 16:37 ` Stephen Hemminger
2025-10-31 16:41 ` [PATCH v2 0/5] BPF enhancements Stephen Hemminger
2025-10-31 16:41 ` [PATCH v2 1/5] bpf: add allocation annotations to functions Stephen Hemminger
2025-10-31 16:41 ` [PATCH v2 2/5] bpf: use bulk free on filtered packets Stephen Hemminger
2025-10-31 16:41 ` [PATCH v2 3/5] bpf: add a test for BPF ELF load Stephen Hemminger
2025-10-31 16:41 ` [PATCH v2 4/5] bpf: add test for Rx and Tx filtering Stephen Hemminger
2025-10-31 16:41 ` [PATCH v2 5/5] bpf: remove use of VLA Stephen Hemminger
2025-11-01 18:04 ` [PATCH v3 0/5] BPF enhancements Stephen Hemminger
2025-11-01 18:04 ` [PATCH v3 1/5] bpf: add allocation annotations to functions Stephen Hemminger
2025-11-02 21:42 ` Konstantin Ananyev
2025-11-01 18:04 ` [PATCH v3 2/5] bpf: use bulk free on filtered packets Stephen Hemminger
2025-11-01 18:04 ` [PATCH v3 3/5] bpf: add a test for BPF ELF load Stephen Hemminger
2025-11-01 18:04 ` [PATCH v3 4/5] bpf: add test for Rx and Tx filtering Stephen Hemminger
2025-11-01 18:04 ` [PATCH v3 5/5] bpf: remove use of VLA Stephen Hemminger
2025-11-03 9:21 ` Konstantin Ananyev
2025-11-04 16:07 ` [PATCH v4 0/5] BPF enhancements Stephen Hemminger
2025-11-04 16:07 ` [PATCH v4 1/5] bpf: add allocation annotations to functions Stephen Hemminger
2025-11-04 16:07 ` [PATCH v4 2/5] bpf: use bulk free on filtered packets Stephen Hemminger
2025-11-04 16:07 ` [PATCH v4 3/5] bpf: add a test for BPF ELF load Stephen Hemminger
2025-11-04 16:07 ` [PATCH v4 4/5] bpf: add test for Rx and Tx filtering Stephen Hemminger
2025-11-04 16:07 ` Stephen Hemminger [this message]
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