From 99fc16c036f7e6b978a41cce7dc995660d140d96 Mon Sep 17 00:00:00 2001 From: Bhanuprakash Bodireddy Date: Tue, 25 Jul 2017 05:14:44 +0100 Subject: packets: Reorganize the pkt_metadata structure. pkt_metadata_init() is called for every packet in userspace datapath and initializes few members in pkt_metadata. Before this the members that needs to be initialized are prefetched using pkt_metadata_prefetch_init(). The above functions are critical to the userspace datapath performance and should be in sync. Any changes to the pkt_metadata should also include changes to metadata_init() and prefetch_init() if necessary. This commit slightly refactors the pkt_metadata structure and introduces cache line markers to catch any violations to the structure. Also only prefetch the cachelines having the members that needs to be zeroed out. Signed-off-by: Bhanuprakash Bodireddy Signed-off-by: Ben Pfaff --- lib/packets.h | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/packets.h b/lib/packets.h index fabab0840..297a8a94a 100644 --- a/lib/packets.h +++ b/lib/packets.h @@ -92,6 +92,7 @@ flow_tnl_equal(const struct flow_tnl *a, const struct flow_tnl *b) /* Datapath packet metadata */ struct pkt_metadata { +PADDED_MEMBERS_CACHELINE_MARKER(CACHE_LINE_SIZE, cacheline0, uint32_t recirc_id; /* Recirculation id carried with the recirculating packets. 0 for packets received from the wire. */ @@ -104,16 +105,29 @@ struct pkt_metadata { uint16_t ct_zone; /* Connection zone. */ uint32_t ct_mark; /* Connection mark. */ ovs_u128 ct_label; /* Connection label. */ + union flow_in_port in_port; /* Input port. */ +); + +PADDED_MEMBERS_CACHELINE_MARKER(CACHE_LINE_SIZE, cacheline1, union { /* Populated only for non-zero 'ct_state'. */ struct ovs_key_ct_tuple_ipv4 ipv4; struct ovs_key_ct_tuple_ipv6 ipv6; /* Used only if */ } ct_orig_tuple; /* 'ct_orig_tuple_ipv6' is set */ - union flow_in_port in_port; /* Input port. */ +); + +PADDED_MEMBERS_CACHELINE_MARKER(CACHE_LINE_SIZE, cacheline2, struct flow_tnl tunnel; /* Encapsulating tunnel parameters. Note that * if 'ip_dst' == 0, the rest of the fields may * be uninitialized. */ +); }; +BUILD_ASSERT_DECL(offsetof(struct pkt_metadata, cacheline0) == 0); +BUILD_ASSERT_DECL(offsetof(struct pkt_metadata, cacheline1) == + CACHE_LINE_SIZE); +BUILD_ASSERT_DECL(offsetof(struct pkt_metadata, cacheline2) == + 2 * CACHE_LINE_SIZE); + static inline void pkt_metadata_init_tnl(struct pkt_metadata *md) { @@ -148,7 +162,12 @@ pkt_metadata_init(struct pkt_metadata *md, odp_port_t port) static inline void pkt_metadata_prefetch_init(struct pkt_metadata *md) { - ovs_prefetch_range(md, offsetof(struct pkt_metadata, tunnel.ip_src)); + /* Prefetch cacheline0 as members till ct_state and odp_port will + * be initialized later in pkt_metadata_init(). */ + OVS_PREFETCH(md->cacheline0); + + /* Prefetch cachline2 as ip_dst & ipv6_dst fields will be initialized. */ + OVS_PREFETCH(md->cacheline2); } bool dpid_from_string(const char *s, uint64_t *dpidp); -- cgit v1.2.1