[dpdk-dev] [RFC PATCH v2 4/5] lib/bpf: use wait event scheme for Rx/Tx iteration
From: Feifei Wang <hidden>
Date: 2021-09-23 09:59:35
Subsystem:
library code, the rest · Maintainers:
Andrew Morton, Linus Torvalds
First, fix the bug that keyword const of func arg should be after "*".
This is because const before "*" means the value of "cbi" should not be
changed. But we should monitor that cbi->use changed and then we can
jump out of loop.
Second, instead of polling for cbi->use to be updated, use
wait event scheme.
Fixes: a93ff62a8938 ("bpf: introduce basic Rx/Tx filters")
Cc: konstantin.ananyev@intel.com
Cc: stable@dpdk.org
Signed-off-by: Feifei Wang <redacted>
Reviewed-by: Ruifeng Wang <redacted>
---
lib/bpf/bpf_pkt.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/lib/bpf/bpf_pkt.c b/lib/bpf/bpf_pkt.c
index 6e8248f0d6..08ed8ff68c 100644
--- a/lib/bpf/bpf_pkt.c
+++ b/lib/bpf/bpf_pkt.c@@ -111,9 +111,9 @@ bpf_eth_cbi_unuse(struct bpf_eth_cbi *cbi) * Waits till datapath finished using given callback. */ static void -bpf_eth_cbi_wait(const struct bpf_eth_cbi *cbi) +bpf_eth_cbi_wait(struct bpf_eth_cbi *const cbi) { - uint32_t nuse, puse; + uint32_t puse; /* make sure all previous loads and stores are completed */ rte_smp_mb();
@@ -122,11 +122,8 @@ bpf_eth_cbi_wait(const struct bpf_eth_cbi *cbi) /* in use, busy wait till current RX/TX iteration is finished */ if ((puse & BPF_ETH_CBI_INUSE) != 0) { - do { - rte_pause(); - rte_compiler_barrier(); - nuse = cbi->use; - } while (nuse == puse); + rte_compiler_barrier(); + rte_wait_event_32(&cbi->use, UINT_MAX, puse, ==, __ATOMIC_RELAXED); } }
--
2.25.1