[dpdk-dev] [PATCH v5 6/6] examples/ipsec-secgw: add SAD cache

[Vladimir Medvedkin <vladimir.medvedkin@intel.com>]

Introduce SAD cache.
Stores the most recent SA in a per lcore cache.
Cache represents flat array containing SA's indexed by SPI.

Signed-off-by: Vladimir Medvedkin <vladimir.medvedkin@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
---
 examples/ipsec-secgw/ipsec-secgw.c |  30 +++++++++-
 examples/ipsec-secgw/ipsec.h       |   1 +
 examples/ipsec-secgw/sa.c          |  32 +----------
 examples/ipsec-secgw/sad.c         |  40 ++++++++++++++
 examples/ipsec-secgw/sad.h         | 109 ++++++++++++++++++++++++++++++++++---
 5 files changed, 171 insertions(+), 41 deletions(-)

diff --git a/examples/ipsec-secgw/ipsec-secgw.c b/examples/ipsec-secgw/ipsec-secgw.c
index 3e5f82e..32ecd26 100644
--- a/examples/ipsec-secgw/ipsec-secgw.c
+++ b/examples/ipsec-secgw/ipsec-secgw.c
@@ -46,6 +46,7 @@
 
 #include "ipsec.h"
 #include "parser.h"
+#include "sad.h"
 
 #define RTE_LOGTYPE_IPSEC RTE_LOGTYPE_USER1
 
@@ -192,7 +193,10 @@ static uint32_t mtu_size = RTE_ETHER_MTU;
 static uint64_t frag_ttl_ns = MAX_FRAG_TTL_NS;
 
 /* application wide librte_ipsec/SA parameters */
-struct app_sa_prm app_sa_prm = {.enable = 0};
+struct app_sa_prm app_sa_prm = {
+			.enable = 0,
+			.cache_sz = SA_CACHE_SZ
+		};
 static const char *cfgfile;
 
 struct lcore_rx_queue {
@@ -1102,7 +1106,7 @@ main_loop(__attribute__((unused)) void *dummy)
 	uint16_t portid;
 	uint8_t queueid;
 	struct lcore_conf *qconf;
-	int32_t socket_id;
+	int32_t rc, socket_id;
 	const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1)
 			/ US_PER_S * BURST_TX_DRAIN_US;
 	struct lcore_rx_queue *rxql;
@@ -1132,6 +1136,14 @@ main_loop(__attribute__((unused)) void *dummy)
 	qconf->frag.pool_dir = socket_ctx[socket_id].mbuf_pool;
 	qconf->frag.pool_indir = socket_ctx[socket_id].mbuf_pool_indir;
 
+	rc = ipsec_sad_lcore_cache_init(app_sa_prm.cache_sz);
+	if (rc != 0) {
+		RTE_LOG(ERR, IPSEC,
+			"SAD cache init on lcore %u, failed with code: %d\n",
+			lcore_id, rc);
+		return rc;
+	}
+
 	if (qconf->nb_rx_queue == 0) {
 		RTE_LOG(DEBUG, IPSEC, "lcore %u has nothing to do\n",
 			lcore_id);
@@ -1271,6 +1283,7 @@ print_usage(const char *prgname)
 		" [-w REPLAY_WINDOW_SIZE]"
 		" [-e]"
 		" [-a]"
+		" [-c]"
 		" -f CONFIG_FILE"
 		" --config (port,queue,lcore)[,(port,queue,lcore)]"
 		" [--single-sa SAIDX]"
@@ -1290,6 +1303,8 @@ print_usage(const char *prgname)
 		"     size for each SA\n"
 		"  -e enables ESN\n"
 		"  -a enables SA SQN atomic behaviour\n"
+		"  -c specifies inbound SAD cache size,\n"
+		"     zero value disables the cache (default value: 128)\n"
 		"  -f CONFIG_FILE: Configuration file\n"
 		"  --config (port,queue,lcore): Rx queue configuration\n"
 		"  --single-sa SAIDX: Use single SA index for outbound traffic,\n"
@@ -1442,7 +1457,7 @@ parse_args(int32_t argc, char **argv)
 
 	argvopt = argv;
 
-	while ((opt = getopt_long(argc, argvopt, "aelp:Pu:f:j:w:",
+	while ((opt = getopt_long(argc, argvopt, "aelp:Pu:f:j:w:c:",
 				lgopts, &option_index)) != EOF) {
 
 		switch (opt) {
@@ -1501,6 +1516,15 @@ parse_args(int32_t argc, char **argv)
 			app_sa_prm.enable = 1;
 			app_sa_prm.flags |= RTE_IPSEC_SAFLAG_SQN_ATOM;
 			break;
+		case 'c':
+			ret = parse_decimal(optarg);
+			if (ret < 0) {
+				printf("Invalid SA cache size: %s\n", optarg);
+				print_usage(prgname);
+				return -1;
+			}
+			app_sa_prm.cache_sz = ret;
+			break;
 		case CMD_LINE_OPT_CONFIG_NUM:
 			ret = parse_config(optarg);
 			if (ret) {
diff --git a/examples/ipsec-secgw/ipsec.h b/examples/ipsec-secgw/ipsec.h
index 3c77232..4f2fd61 100644
--- a/examples/ipsec-secgw/ipsec.h
+++ b/examples/ipsec-secgw/ipsec.h
@@ -81,6 +81,7 @@ struct app_sa_prm {
 	uint32_t enable; /* use librte_ipsec API for ipsec pkt processing */
 	uint32_t window_size; /* replay window size */
 	uint32_t enable_esn;  /* enable/disable ESN support */
+	uint32_t cache_sz;	/* per lcore SA cache size */
 	uint64_t flags;       /* rte_ipsec_sa_prm.flags */
 };
 
diff --git a/examples/ipsec-secgw/sa.c b/examples/ipsec-secgw/sa.c
index b3b83e3..099a11b 100644
--- a/examples/ipsec-secgw/sa.c
+++ b/examples/ipsec-secgw/sa.c
@@ -839,7 +839,7 @@ sa_create(const char *name, int32_t socket_id, uint32_t nb_sa)
 		return NULL;
 	}
 
-	sa_ctx = rte_malloc(NULL, sizeof(struct sa_ctx) +
+	sa_ctx = rte_zmalloc(NULL, sizeof(struct sa_ctx) +
 		sizeof(struct ipsec_sa) * nb_sa, RTE_CACHE_LINE_SIZE);
 
 	if (sa_ctx == NULL) {
@@ -1451,9 +1451,6 @@ inbound_sa_lookup(struct sa_ctx *sa_ctx, struct rte_mbuf *pkts[],
 		void *sa_arr[], uint16_t nb_pkts)
 {
 	uint32_t i;
-	struct ip *ip;
-	uint32_t *src4_addr;
-	uint8_t *src6_addr;
 	void *result_sa;
 	struct ipsec_sa *sa;
 
@@ -1479,32 +1476,7 @@ inbound_sa_lookup(struct sa_ctx *sa_ctx, struct rte_mbuf *pkts[],
 			intsa |= IPSEC_SA_OFFLOAD_FALLBACK_FLAG;
 			result_sa = (void *)intsa;
 		}
-
-		ip = rte_pktmbuf_mtod(pkts[i], struct ip *);
-		switch (WITHOUT_TRANSPORT_VERSION(sa->flags)) {
-		case IP4_TUNNEL:
-			src4_addr = RTE_PTR_ADD(ip,
-				offsetof(struct ip, ip_src));
-			if ((ip->ip_v == IPVERSION) &&
-					(sa->src.ip.ip4 == *src4_addr) &&
-					(sa->dst.ip.ip4 == *(src4_addr + 1)))
-				sa_arr[i] = result_sa;
-			else
-				sa_arr[i] = NULL;
-			break;
-		case IP6_TUNNEL:
-			src6_addr = RTE_PTR_ADD(ip,
-				offsetof(struct ip6_hdr, ip6_src));
-			if ((ip->ip_v == IP6_VERSION) &&
-				!memcmp(&sa->src.ip.ip6.ip6, src6_addr, 16) &&
-				!memcmp(&sa->dst.ip.ip6.ip6, src6_addr + 16, 16))
-				sa_arr[i] = result_sa;
-			else
-				sa_arr[i] = NULL;
-			break;
-		case TRANSPORT:
-			sa_arr[i] = result_sa;
-		}
+		sa_arr[i] = result_sa;
 	}
 }
 
diff --git a/examples/ipsec-secgw/sad.c b/examples/ipsec-secgw/sad.c
index fd31101..5b2c0e6 100644
--- a/examples/ipsec-secgw/sad.c
+++ b/examples/ipsec-secgw/sad.c
@@ -3,10 +3,17 @@
  */
 
 #include <rte_errno.h>
+#include <rte_malloc.h>
 
 #include "ipsec.h"
 #include "sad.h"
 
+RTE_DEFINE_PER_LCORE(struct ipsec_sad_cache, sad_cache) = {
+	.v4 = NULL,
+	.v6 = NULL,
+	.mask = 0,
+};
+
 int
 ipsec_sad_add(struct ipsec_sad *sad, struct ipsec_sa *sa)
 {
@@ -65,6 +72,39 @@ ipsec_sad_add(struct ipsec_sad *sad, struct ipsec_sa *sa)
 	return 0;
 }
 
+/*
+ * Init per lcore SAD cache.
+ * Must be called by every processing lcore.
+ */
+int
+ipsec_sad_lcore_cache_init(uint32_t nb_cache_ent)
+{
+	uint32_t cache_elem;
+	size_t cache_mem_sz;
+	struct ipsec_sad_cache *cache;
+
+	cache = &RTE_PER_LCORE(sad_cache);
+
+	cache_elem = rte_align32pow2(nb_cache_ent);
+	cache_mem_sz = sizeof(struct ipsec_sa *) * cache_elem;
+
+	if (cache_mem_sz != 0) {
+		cache->v4 = rte_zmalloc_socket(NULL, cache_mem_sz,
+			RTE_CACHE_LINE_SIZE, rte_socket_id());
+		if (cache->v4 == NULL)
+			return -rte_errno;
+
+		cache->v6 = rte_zmalloc_socket(NULL, cache_mem_sz,
+			RTE_CACHE_LINE_SIZE, rte_socket_id());
+		if (cache->v6 == NULL)
+			return -rte_errno;
+
+		cache->mask = cache_elem - 1;
+	}
+
+	return 0;
+}
+
 int
 ipsec_sad_create(const char *name, struct ipsec_sad *sad,
 	int socket_id, struct ipsec_sa_cnt *sa_cnt)
diff --git a/examples/ipsec-secgw/sad.h b/examples/ipsec-secgw/sad.h
index 29ed0f8..81a6ff2 100644
--- a/examples/ipsec-secgw/sad.h
+++ b/examples/ipsec-secgw/sad.h
@@ -7,6 +7,17 @@
 
 #include <rte_ipsec_sad.h>
 
+#define SA_CACHE_SZ	128
+#define SPI2IDX(spi, mask)	((spi) & (mask))
+
+struct ipsec_sad_cache {
+	struct ipsec_sa **v4;
+	struct ipsec_sa **v6;
+	uint32_t mask;
+};
+
+RTE_DECLARE_PER_LCORE(struct ipsec_sad_cache, sad_cache);
+
 struct ipsec_sad {
 	struct rte_ipsec_sad *sad_v4;
 	struct rte_ipsec_sad *sad_v6;
@@ -17,8 +28,42 @@ int ipsec_sad_create(const char *name, struct ipsec_sad *sad,
 
 int ipsec_sad_add(struct ipsec_sad *sad, struct ipsec_sa *sa);
 
+int ipsec_sad_lcore_cache_init(uint32_t nb_cache_ent);
+
+static inline int
+cmp_sa_key(struct ipsec_sa *sa, int is_v4, struct rte_ipv4_hdr *ipv4,
+	struct rte_ipv6_hdr *ipv6)
+{
+	int sa_type = WITHOUT_TRANSPORT_VERSION(sa->flags);
+	if ((sa_type == TRANSPORT) ||
+			/* IPv4 check */
+			(is_v4 && (sa_type == IP4_TUNNEL) &&
+			(sa->src.ip.ip4 == ipv4->src_addr) &&
+			(sa->dst.ip.ip4 == ipv4->dst_addr)) ||
+			/* IPv6 check */
+			(!is_v4 && (sa_type == IP6_TUNNEL) &&
+			(!memcmp(sa->src.ip.ip6.ip6, ipv6->src_addr, 16)) &&
+			(!memcmp(sa->dst.ip.ip6.ip6, ipv6->dst_addr, 16))))
+		return 1;
+
+	return 0;
+}
+
 static inline void
-sad_lookup(const struct ipsec_sad *sad, struct rte_mbuf *pkts[],
+sa_cache_update(struct ipsec_sa **sa_cache, struct ipsec_sa *sa, uint32_t mask)
+{
+	uint32_t cache_idx;
+
+	/* SAD cache is disabled */
+	if (mask == 0)
+		return;
+
+	cache_idx = SPI2IDX(sa->spi, mask);
+	sa_cache[cache_idx] = sa;
+}
+
+static inline void
+sad_lookup(struct ipsec_sad *sad, struct rte_mbuf *pkts[],
 	void *sa[], uint16_t nb_pkts)
 {
 	uint32_t i;
@@ -34,13 +79,39 @@ sad_lookup(const struct ipsec_sad *sad, struct rte_mbuf *pkts[],
 	const union rte_ipsec_sad_key	*keys_v6[nb_pkts];
 	void *v4_res[nb_pkts];
 	void *v6_res[nb_pkts];
+	uint32_t spi, cache_idx;
+	struct ipsec_sad_cache *cache;
+	struct ipsec_sa *cached_sa;
+	int is_ipv4;
+
+	cache  = &RTE_PER_LCORE(sad_cache);
 
 	/* split received packets by address family into two arrays */
 	for (i = 0; i < nb_pkts; i++) {
 		ipv4 = rte_pktmbuf_mtod(pkts[i], struct rte_ipv4_hdr *);
+		ipv6 = rte_pktmbuf_mtod(pkts[i], struct rte_ipv6_hdr *);
 		esp = rte_pktmbuf_mtod_offset(pkts[i], struct rte_esp_hdr *,
 				pkts[i]->l3_len);
-		if ((ipv4->version_ihl >> 4) == IPVERSION) {
+
+		is_ipv4 = ((ipv4->version_ihl >> 4) == IPVERSION);
+		spi = rte_be_to_cpu_32(esp->spi);
+		cache_idx = SPI2IDX(spi, cache->mask);
+
+		if (is_ipv4) {
+			cached_sa = (cache->mask != 0) ?
+				cache->v4[cache_idx] : NULL;
+			/* check SAD cache entry */
+			if ((cached_sa != NULL) && (cached_sa->spi == spi)) {
+				if (cmp_sa_key(cached_sa, 1, ipv4, ipv6)) {
+					/* cache hit */
+					sa[i] = cached_sa;
+					continue;
+				}
+			}
+			/*
+			 * cache miss
+			 * preparing sad key to proceed with sad lookup
+			 */
 			v4[nb_v4].spi = esp->spi;
 			v4[nb_v4].dip = ipv4->dst_addr;
 			v4[nb_v4].sip = ipv4->src_addr;
@@ -48,7 +119,14 @@ sad_lookup(const struct ipsec_sad *sad, struct rte_mbuf *pkts[],
 						&v4[nb_v4];
 			v4_idxes[nb_v4++] = i;
 		} else {
-			ipv6 = rte_pktmbuf_mtod(pkts[i], struct rte_ipv6_hdr *);
+			cached_sa = (cache->mask != 0) ?
+				cache->v6[cache_idx] : NULL;
+			if ((cached_sa != NULL) && (cached_sa->spi == spi)) {
+				if (cmp_sa_key(cached_sa, 0, ipv4, ipv6)) {
+					sa[i] = cached_sa;
+					continue;
+				}
+			}
 			v6[nb_v6].spi = esp->spi;
 			memcpy(v6[nb_v6].dip, ipv6->dst_addr,
 					sizeof(ipv6->dst_addr));
@@ -65,11 +143,26 @@ sad_lookup(const struct ipsec_sad *sad, struct rte_mbuf *pkts[],
 	if (nb_v6 != 0)
 		rte_ipsec_sad_lookup(sad->sad_v6, keys_v6, v6_res, nb_v6);
 
-	for (i = 0; i < nb_v4; i++)
-		sa[v4_idxes[i]] = v4_res[i];
-
-	for (i = 0; i < nb_v6; i++)
-		sa[v6_idxes[i]] = v6_res[i];
+	for (i = 0; i < nb_v4; i++) {
+		ipv4 = rte_pktmbuf_mtod(pkts[v4_idxes[i]],
+			struct rte_ipv4_hdr *);
+		if (cmp_sa_key(v4_res[i], 1, ipv4, NULL)) {
+			sa[v4_idxes[i]] = v4_res[i];
+			sa_cache_update(cache->v4, (struct ipsec_sa *)v4_res[i],
+				cache->mask);
+		} else
+			sa[v4_idxes[i]] = NULL;
+	}
+	for (i = 0; i < nb_v6; i++) {
+		ipv6 = rte_pktmbuf_mtod(pkts[v6_idxes[i]],
+			struct rte_ipv6_hdr *);
+		if (cmp_sa_key(v6_res[i], 0, NULL, ipv6)) {
+			sa[v6_idxes[i]] = v6_res[i];
+			sa_cache_update(cache->v6, (struct ipsec_sa *)v6_res[i],
+				cache->mask);
+		} else
+			sa[v6_idxes[i]] = NULL;
+	}
 }
 
 #endif /* __SAD_H__ */
-- 
2.7.4