The table entries were updated field by field. There were two issues: 1. bitwise operations are read-modify-write sequences and not atomic, nor efficient. 2. the above non-atomic operations causes entries out of synchronization and inconsistency. This patch combines the fields into a one-go 32bit entry update to avoid inconsistency and as a bonus save CPU cycles.
Suggested-by: Gavin Hu <gavin...@arm.com> Signed-off-by: Ruifeng Wang <ruifeng.w...@arm.com> Reviewed-by: Gavin Hu <gavin...@arm.com> --- lib/librte_lpm/rte_lpm.c | 35 +++++++++++++++++++++++++---------- 1 file changed, 25 insertions(+), 10 deletions(-) diff --git a/lib/librte_lpm/rte_lpm.c b/lib/librte_lpm/rte_lpm.c index d86248713..95e2f75aa 100644 --- a/lib/librte_lpm/rte_lpm.c +++ b/lib/librte_lpm/rte_lpm.c @@ -906,9 +906,14 @@ add_depth_big_v20(struct rte_lpm_v20 *lpm, uint32_t ip_masked, uint8_t depth, /* Set tbl8 entry. */ for (i = tbl8_index; i < (tbl8_index + tbl8_range); i++) { - lpm->tbl8[i].depth = depth; - lpm->tbl8[i].next_hop = next_hop; - lpm->tbl8[i].valid = VALID; + struct rte_lpm_tbl_entry_v20 new_tbl8_entry = { + .valid = VALID, + .depth = depth, + .valid_group = lpm->tbl8[i].valid_group, + }; + new_tbl8_entry.next_hop = next_hop; + __atomic_store(&lpm->tbl8[i], &new_tbl8_entry, + __ATOMIC_RELAXED); } /* @@ -943,19 +948,29 @@ add_depth_big_v20(struct rte_lpm_v20 *lpm, uint32_t ip_masked, uint8_t depth, /* Populate new tbl8 with tbl24 value. */ for (i = tbl8_group_start; i < tbl8_group_end; i++) { - lpm->tbl8[i].valid = VALID; - lpm->tbl8[i].depth = lpm->tbl24[tbl24_index].depth; - lpm->tbl8[i].next_hop = - lpm->tbl24[tbl24_index].next_hop; + struct rte_lpm_tbl_entry_v20 new_tbl8_entry = { + .valid = VALID, + .depth = lpm->tbl24[tbl24_index].depth, + .valid_group = lpm->tbl8[i].valid_group, + }; + new_tbl8_entry.next_hop = + lpm->tbl24[tbl24_index].next_hop; + __atomic_store(&lpm->tbl8[i], &new_tbl8_entry, + __ATOMIC_RELAXED); } tbl8_index = tbl8_group_start + (ip_masked & 0xFF); /* Insert new rule into the tbl8 entry. */ for (i = tbl8_index; i < tbl8_index + tbl8_range; i++) { - lpm->tbl8[i].valid = VALID; - lpm->tbl8[i].depth = depth; - lpm->tbl8[i].next_hop = next_hop; + struct rte_lpm_tbl_entry_v20 new_tbl8_entry = { + .valid = VALID, + .depth = depth, + .valid_group = lpm->tbl8[i].valid_group, + }; + new_tbl8_entry.next_hop = next_hop; + __atomic_store(&lpm->tbl8[i], &new_tbl8_entry, + __ATOMIC_RELAXED); } /* -- 2.17.1