From 49efb1f5b0ea45bdb75d578460a7866a58167d1f Mon Sep 17 00:00:00 2001 From: "Denis V. Lunev" Date: Thu, 14 Jul 2016 16:33:24 +0300 Subject: [PATCH] mirror: create mirror_throttle helper The patch also places last_pause_ns from stack in mirror_run into MirrorBlockJob structure. This helper will be useful in next patches. Signed-off-by: Denis V. Lunev Reviewed-by: Eric Blake Message-id: 1468503209-19498-4-git-send-email-den@openvz.org CC: Vladimir Sementsov-Ogievskiy CC: Eric Blake CC: Stefan Hajnoczi CC: Fam Zheng CC: Kevin Wolf CC: Max Reitz CC: Jeff Cody Signed-off-by: Jeff Cody --- block/mirror.c | 31 +++++++++++++++++++------------ 1 file changed, 19 insertions(+), 12 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index fbacee234b..5fde13b1f5 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -58,6 +58,7 @@ typedef struct MirrorBlockJob { QSIMPLEQ_HEAD(, MirrorBuffer) buf_free; int buf_free_count; + uint64_t last_pause_ns; unsigned long *in_flight_bitmap; int in_flight; int64_t sectors_in_flight; @@ -514,6 +515,18 @@ static void mirror_exit(BlockJob *job, void *opaque) bdrv_unref(src); } +static void mirror_throttle(MirrorBlockJob *s) +{ + int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + + if (now - s->last_pause_ns > SLICE_TIME) { + s->last_pause_ns = now; + block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0); + } else { + block_job_pause_point(&s->common); + } +} + static void coroutine_fn mirror_run(void *opaque) { MirrorBlockJob *s = opaque; @@ -521,7 +534,6 @@ static void coroutine_fn mirror_run(void *opaque) BlockDriverState *bs = blk_bs(s->common.blk); BlockDriverState *target_bs = blk_bs(s->target); int64_t sector_num, end, length; - uint64_t last_pause_ns; BlockDriverInfo bdi; char backing_filename[2]; /* we only need 2 characters because we are only checking for a NULL string */ @@ -577,7 +589,7 @@ static void coroutine_fn mirror_run(void *opaque) mirror_free_init(s); - last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + 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; @@ -587,14 +599,8 @@ static void coroutine_fn mirror_run(void *opaque) /* Just to make sure we are not exceeding int limit. */ int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS, end - sector_num); - 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); - } else { - block_job_pause_point(&s->common); - } + mirror_throttle(s); if (block_job_is_cancelled(&s->common)) { goto immediate_exit; @@ -617,7 +623,7 @@ static void coroutine_fn mirror_run(void *opaque) bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi); for (;;) { uint64_t delay_ns = 0; - int64_t cnt; + int64_t cnt, delta; bool should_complete; if (s->ret < 0) { @@ -640,7 +646,8 @@ static void coroutine_fn mirror_run(void *opaque) * We do so every SLICE_TIME nanoseconds, or when there is an error, * or when the source is clean, whichever comes first. */ - if (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - last_pause_ns < SLICE_TIME && + delta = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - s->last_pause_ns; + if (delta < SLICE_TIME && s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) { if (s->in_flight == MAX_IN_FLIGHT || s->buf_free_count == 0 || (cnt == 0 && s->in_flight > 0)) { @@ -710,7 +717,7 @@ static void coroutine_fn mirror_run(void *opaque) s->common.cancelled = false; break; } - last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + s->last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); } immediate_exit: