bpf: replace use of VLA

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 <[email protected]>
Acked-by: Konstantin Ananyev <[email protected]>
Reviewed-by: Marat Khalili <[email protected]>

Author: shemminger

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++) {