@@ -166,14 +166,14 @@ pkt_metadata_prefetch_init(struct pkt_metadata *md)
{
/* Prefetch cacheline0 as members till ct_state and odp_port will
* be initialized later in pkt_metadata_init(). */
- OVS_PREFETCH(md->cacheline0);
+ OVS_PREFETCH_CACHE(md->cacheline0, OPCH_NTR);
/* Prefetch cacheline1 as members of this cacheline will be zeroed out
* in pkt_metadata_init_tnl(). */
- OVS_PREFETCH(md->cacheline1);
+ OVS_PREFETCH_CACHE(md->cacheline1, OPCH_NTR);
/* Prefetch cachline2 as ip_dst & ipv6_dst fields will be initialized. */
- OVS_PREFETCH(md->cacheline2);
+ OVS_PREFETCH_CACHE(md->cacheline2, OPCH_NTR);
}
bool dpid_from_string(const char *s, uint64_t *dpidp);
OVS_PREFETCH by default uses OPCH_HTR(High Temporal Read), meaning the prefetch is in preparation for a future read and the prefetched data is made available in all levels of caches. However the pkt_metadata_prefetch_init() prefetches the metadata so that the data is readily available when pkt_metadata_init() zeroes out the same. So a 'write' operation is actually performed instead of anticipated 'read' on the prefetched data. Doing a 'write' isn't a problem as the metadata isn't shared between the threads and doesn't need invalidation across other cores and so read prefetch is enough with *non-temporal* reference so not to pollute the cache. This change seems to positively affect performance. Signed-off-by: Bhanuprakash Bodireddy <bhanuprakash.bodireddy@intel.com> --- lib/packets.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)