From e266f52cfb77e9fb162d3d02230170a373076d85 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Fri, 21 Aug 2020 21:53:46 +0200 Subject: [PATCH] block/nvme: Avoid further processing if trace event not enabled MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Avoid further processing if TRACE_NVME_SUBMIT_COMMAND_RAW is not enabled. This is an untested intend of performance optimization. Reviewed-by: Stefan Hajnoczi Signed-off-by: Philippe Mathieu-Daudé Message-Id: <20200821195359.1285345-3-philmd@redhat.com> Signed-off-by: Kevin Wolf --- block/nvme.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/nvme.c b/block/nvme.c index a2b006be56..4d4f728159 100644 --- a/block/nvme.c +++ b/block/nvme.c @@ -441,6 +441,9 @@ static void nvme_trace_command(const NvmeCmd *cmd) { int i; + if (!trace_event_get_state_backends(TRACE_NVME_SUBMIT_COMMAND_RAW)) { + return; + } for (i = 0; i < 8; ++i) { uint8_t *cmdp = (uint8_t *)cmd + i * 8; trace_nvme_submit_command_raw(cmdp[0], cmdp[1], cmdp[2], cmdp[3],