From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45021) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YsN4u-0008Om-P2 for qemu-devel@nongnu.org; Tue, 12 May 2015 23:11:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YsN4t-0001HK-Ph for qemu-devel@nongnu.org; Tue, 12 May 2015 23:11:24 -0400 From: Fam Zheng Date: Wed, 13 May 2015 11:11:13 +0800 Message-Id: <1431486673-19280-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH] block/mirror: Sleep periodically during bitmap scanning List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , pbonzini@redhat.com, Jeff Cody , qemu-block@nongnu.org Before, we only yield after initializing dirty bitmap, where the QMP command would return. That may take very long, and guest IO will be blocked. Add sleep points like the later mirror iterations. Signed-off-by: Fam Zheng --- block/mirror.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/block/mirror.c b/block/mirror.c index 1a1d997..baed225 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -467,11 +467,23 @@ static void coroutine_fn mirror_run(void *opaque) sectors_per_chunk = s->granularity >> BDRV_SECTOR_BITS; mirror_free_init(s); + last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); if (!s->is_none_mode) { /* First part, loop on the sectors and initialize the dirty bitmap. */ BlockDriverState *base = s->base; for (sector_num = 0; sector_num < end; ) { int64_t next = (sector_num | (sectors_per_chunk - 1)) + 1; + int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + + if (now - last_pause_ns > SLICE_TIME) { + last_pause_ns = now; + block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0); + } + + if (block_job_is_cancelled(&s->common)) { + goto immediate_exit; + } + ret = bdrv_is_allocated_above(bs, base, sector_num, next - sector_num, &n); @@ -490,7 +502,6 @@ static void coroutine_fn mirror_run(void *opaque) } bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi); - last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); for (;;) { uint64_t delay_ns = 0; int64_t cnt; -- 2.4.0