From 9b3702c45245f7bbb51350c25e8cf304c490b96a Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 7 Nov 2013 07:19:42 +0100 Subject: [PATCH 05/81] block: make bdrv_co_is_allocated static RH-Author: Paolo Bonzini Message-id: <1382084091-16636-6-git-send-email-pbonzini@redhat.com> Patchwork-id: 54988 O-Subject: [RHEL 7.0 qemu-kvm PATCH 05/26] block: make bdrv_co_is_allocated static Bugzilla: 989646 RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Max Reitz RH-Acked-by: Kevin Wolf bdrv_is_allocated can detect coroutine context and go through a fast path, similar to other block layer functions. Reviewed-by: Eric Blake Signed-off-by: Paolo Bonzini (cherry picked from commit bdad13b9deec47d5d9eaf7f43867d19a79471244) Signed-off-by: Miroslav Rezanina --- block.c | 24 +++++++++++++++--------- block/raw.c | 2 +- block/stream.c | 4 ++-- include/block/block.h | 2 -- 4 files changed, 18 insertions(+), 14 deletions(-) diff --git a/block.c b/block.c index d5aeff7..0607cc6 100644 --- a/block.c +++ b/block.c @@ -2555,7 +2555,7 @@ static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs, if (flags & BDRV_REQ_COPY_ON_READ) { int pnum; - ret = bdrv_co_is_allocated(bs, sector_num, nb_sectors, &pnum); + ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum); if (ret < 0) { goto out; } @@ -3027,8 +3027,9 @@ typedef struct BdrvCoIsAllocatedData { * 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes * beyond the end of the disk image it will be clamped. */ -int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, int *pnum) +static int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, + int64_t sector_num, + int nb_sectors, int *pnum) { int64_t n; @@ -3078,10 +3079,15 @@ int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, .done = false, }; - co = qemu_coroutine_create(bdrv_is_allocated_co_entry); - qemu_coroutine_enter(co, &data); - while (!data.done) { - qemu_aio_wait(); + if (qemu_in_coroutine()) { + /* Fast-path if already in coroutine context */ + bdrv_is_allocated_co_entry(&data); + } else { + co = qemu_coroutine_create(bdrv_is_allocated_co_entry); + qemu_coroutine_enter(co, &data); + while (!data.done) { + qemu_aio_wait(); + } } return data.ret; } @@ -3109,8 +3115,8 @@ int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top, intermediate = top; while (intermediate && intermediate != base) { int pnum_inter; - ret = bdrv_co_is_allocated(intermediate, sector_num, nb_sectors, - &pnum_inter); + ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors, + &pnum_inter); if (ret < 0) { return ret; } else if (ret) { diff --git a/block/raw.c b/block/raw.c index 8c81de9..f78ff39 100644 --- a/block/raw.c +++ b/block/raw.c @@ -39,7 +39,7 @@ static int coroutine_fn raw_co_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum) { - return bdrv_co_is_allocated(bs->file, sector_num, nb_sectors, pnum); + return bdrv_is_allocated(bs->file, sector_num, nb_sectors, pnum); } static int coroutine_fn raw_co_write_zeroes(BlockDriverState *bs, diff --git a/block/stream.c b/block/stream.c index d6df06f..f8efa8a 100644 --- a/block/stream.c +++ b/block/stream.c @@ -115,8 +115,8 @@ wait: break; } - ret = bdrv_co_is_allocated(bs, sector_num, - STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n); + ret = bdrv_is_allocated(bs, sector_num, + STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n); if (ret == 1) { /* Allocated in the top, no need to copy. */ copy = false; diff --git a/include/block/block.h b/include/block/block.h index 1a3ed22..1932e67 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -192,8 +192,6 @@ int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num, */ int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num, int nb_sectors); -int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, int *pnum); int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top, BlockDriverState *base, int64_t sector_num, -- 1.7.1