diff options
author | Sirshak Das <sirshak.das@arm.com> | 2019-02-05 01:33:33 -0600 |
---|---|---|
committer | Florin Coras <florin.coras@gmail.com> | 2019-04-16 19:33:21 +0000 |
commit | 28aa539f7da7b172d0f35ea9a63f3986939477f7 (patch) | |
tree | be856eb44878b604b2fc93beffb7268db77b457b /src/tests/vnet/session/udp_echo.c | |
parent | 39d04099467414175803273433c95a96c0276252 (diff) |
svm_fifo rework to avoid contention on cursize
Problems Addressed:
- Contention of cursize by producer and consumer.
- Reduce the no of modulo operations.
Changes:
- Synchronization between producer and consumer changed from cursize
to head and tail indexes
Implications: reduces the usable size of fifo by 1.
- Using weaker memory ordering C++11 atomics to access head and tail
based on producer and consumer role.
- Head and tail indexes are unsigned 32 bit integers. Additions and
subtraction on them are implicit 32 bit Modulo operation.
- Adding weaker memory ordering variants of max_enq, max_deq, is_empty
and is_full Using them appropriately in all places.
Perfomance improvement (iperf3 via Hoststack):
iperf3 Server: Marvell ThunderX2(AArch64) - iperf3 Client: Skylake(x86)
~6%(256 rxd/txd) - ~11%(2048 rxd/txd)
Change-Id: I1d484e000e437430fdd5a819657d1c6b62443018
Signed-off-by: Sirshak Das <sirshak.das@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Diffstat (limited to 'src/tests/vnet/session/udp_echo.c')
-rw-r--r-- | src/tests/vnet/session/udp_echo.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/src/tests/vnet/session/udp_echo.c b/src/tests/vnet/session/udp_echo.c index 4fd6c8635a8..91d5dccedcc 100644 --- a/src/tests/vnet/session/udp_echo.c +++ b/src/tests/vnet/session/udp_echo.c @@ -454,7 +454,7 @@ cut_through_thread_fn (void *arg) else { /* We don't do anything with the data, drop it */ - actual_transfer = svm_fifo_max_dequeue (rx_fifo); + actual_transfer = svm_fifo_max_dequeue_cons (rx_fifo); svm_fifo_dequeue_drop (rx_fifo, actual_transfer); } } @@ -724,7 +724,7 @@ send_test_chunk (udp_echo_main_t * utm, app_session_t * s, u32 bytes) test_buf_offset = utm->bytes_sent % test_buf_len; bytes_this_chunk = clib_min (test_buf_len - test_buf_offset, utm->bytes_to_send); - enq_space = svm_fifo_max_enqueue (s->tx_fifo); + enq_space = svm_fifo_max_enqueue_prod (s->tx_fifo); bytes_this_chunk = clib_min (bytes_this_chunk, enq_space); written = app_send (s, test_data + test_buf_offset, bytes_this_chunk, @@ -975,7 +975,8 @@ server_handle_fifo_event_rx (udp_echo_main_t * utm, u32 session_index) rx_fifo = session->rx_fifo; tx_fifo = session->tx_fifo; - max_dequeue = svm_fifo_max_dequeue (rx_fifo); + + max_dequeue = svm_fifo_max_dequeue_cons (rx_fifo); /* Allow enqueuing of a new event */ svm_fifo_unset_event (rx_fifo); |