From 28aa539f7da7b172d0f35ea9a63f3986939477f7 Mon Sep 17 00:00:00 2001 From: Sirshak Das Date: Tue, 5 Feb 2019 01:33:33 -0600 Subject: 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 Reviewed-by: Honnappa Nagarahalli --- src/plugins/unittest/tcp_test.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'src/plugins/unittest/tcp_test.c') diff --git a/src/plugins/unittest/tcp_test.c b/src/plugins/unittest/tcp_test.c index fb01adb6c1f..c8d9d5fe247 100644 --- a/src/plugins/unittest/tcp_test.c +++ b/src/plugins/unittest/tcp_test.c @@ -1221,8 +1221,7 @@ tcp_test_fifo3 (vlib_main_t * vm, unformat_input_t * input) /* manually set head and tail pointers to validate modular arithmetic */ fifo_initial_offset = fifo_initial_offset % fifo_size; - f->head = fifo_initial_offset; - f->tail = fifo_initial_offset; + svm_fifo_init_pointers (f, fifo_initial_offset); for (i = !randomize; i < vec_len (generate); i++) { -- cgit 1.2.3-korg