From 3e98c2443f5c7f127b5b7492a3089e92a1c85112 Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Fri, 28 Feb 2020 18:52:28 -0800 Subject: [PATCH] nvme: Check for readiness more quickly, to speed up boot time After initialization, nvme_wait_ready checks for readiness every 100ms, even though the drive may be ready far sooner than that. This delays system boot by hundreds of milliseconds. Reduce the delay, checking for readiness every millisecond instead. Boot-time tests on an AWS c5.12xlarge: Before: [ 0.546936] initcall nvme_init+0x0/0x5b returned 0 after 37 usecs ... [ 0.764178] nvme nvme0: 2/0/0 default/read/poll queues [ 0.768424] nvme0n1: p1 [ 0.774132] EXT4-fs (nvme0n1p1): mounted filesystem with ordered data mode. Opts: (null) [ 0.774146] VFS: Mounted root (ext4 filesystem) on device 259:1. ... [ 0.788141] Run /sbin/init as init process After: [ 0.537088] initcall nvme_init+0x0/0x5b returned 0 after 37 usecs ... [ 0.543457] nvme nvme0: 2/0/0 default/read/poll queues [ 0.548473] nvme0n1: p1 [ 0.554339] EXT4-fs (nvme0n1p1): mounted filesystem with ordered data mode. Opts: (null) [ 0.554344] VFS: Mounted root (ext4 filesystem) on device 259:1. ... [ 0.567931] Run /sbin/init as init process Signed-off-by: Josh Triplett Reviewed-by: Sagi Grimberg Reviewed-by: Chaitanya Kulkarni Signed-off-by: Keith Busch --- drivers/nvme/host/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index c998894..0e38e07 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2078,7 +2078,7 @@ static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled) if ((csts & NVME_CSTS_RDY) == bit) break; - msleep(100); + usleep_range(1000, 2000); if (fatal_signal_pending(current)) return -EINTR; if (time_after(jiffies, timeout)) { -- 2.7.4