mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
c9ce8c4da6
qemu/block
History
Eric Blake c9ce8c4da6 block: Add flag to avoid wasted work in bdrv_is_allocated() 
Not all callers care about which BDS owns the mapping for a given
range of the file, or where the zeroes lie within that mapping.  In
particular, bdrv_is_allocated() cares more about finding the
largest run of allocated data from the guest perspective, whether
or not that data is consecutive from the host perspective, and
whether or not the data reads as zero.  Therefore, doing subsequent
refinements such as checking how much of the format-layer
allocation also satisfies BDRV_BLOCK_ZERO at the protocol layer is
wasted work - in the best case, it just costs extra CPU cycles
during a single bdrv_is_allocated(), but in the worst case, it
results in a smaller *pnum, and forces callers to iterate through
more status probes when visiting the entire file for even more
extra CPU cycles.

This patch only optimizes the block layer (no behavior change when
want_zero is true, but skip unnecessary effort when it is false).
Then when subsequent patches tweak the driver callback to be
byte-based, we can also pass this hint through to the driver.

Tweak BdrvCoGetBlockStatusData to declare arguments in parameter
order, rather than mixing things up (minimizing padding is not
necessary here).

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-26 14:45:57 +02:00
..
accounting.c block: make accounting thread-safe 2017-06-16 07:55:00 +08:00
backup.c dirty-bitmap: Change bdrv_dirty_iter_next() to report byte offset 2017-10-06 16:28:58 +02:00
blkdebug.c config: qemu_config_parse() return number of config groups 2017-10-09 23:21:52 -03:00
blkreplay.c block: change variable names in BlockDriverState 2017-06-26 14:54:46 +02:00
blkverify.c blkverify: Catch bs->exact_filename overflow 2017-06-26 14:54:46 +02:00
block-backend.c block: tidy ThrottleGroupMember initializations 2017-09-05 16:47:52 +02:00
bochs.c block: do not set BDS read_only if copy_on_read enabled 2017-04-24 15:09:33 -04:00
cloop.c block: do not set BDS read_only if copy_on_read enabled 2017-04-24 15:09:33 -04:00
commit.c commit: Remove overlay_bs 2017-10-06 16:28:58 +02:00
crypto.c block: support passthrough of BDRV_REQ_FUA in crypto driver 2017-10-06 16:30:47 +02:00
crypto.h qcow: convert QCow to use QCryptoBlock for encryption 2017-07-11 17:44:56 +02:00
curl.c curl: do not do aio_poll when waiting for a free CURLState 2017-05-16 10:34:50 -04:00
dirty-bitmap.c dirty-bitmap: Convert internal hbitmap size/granularity 2017-10-06 16:28:58 +02:00
dmg-bz2.c dmg: Move libbz2 code to dmg-bz2.so 2016-10-07 14:14:06 +02:00
dmg.c dmg: use DIV_ROUND_UP 2017-08-31 12:29:07 +02:00
dmg.h dmg: Move libbz2 code to dmg-bz2.so 2016-10-07 14:14:06 +02:00
file-posix.c file-posix: Clear out first sector in hdev_create 2017-09-26 14:46:23 +02:00
file-win32.c qapi: Change data type of the FOO_lookup generated for enum FOO 2017-09-04 13:09:13 +02:00
gluster.c qapi: Change data type of the FOO_lookup generated for enum FOO 2017-09-04 13:09:13 +02:00
io.c block: Add flag to avoid wasted work in bdrv_is_allocated() 2017-10-26 14:45:57 +02:00
iscsi-opts.c block/iscsi: statically link qemu_iscsi_opts 2017-01-27 18:07:58 +01:00
iscsi.c scsi: move block/scsi.h to include/scsi/constants.h 2017-09-19 14:09:31 +02:00
linux-aio.c block: explicitly acquire aiocontext in aio callbacks that need it 2017-02-21 11:39:39 +00:00
Makefile.objs block: add throttle block filter driver 2017-09-06 10:12:02 +02:00
mirror.c block: Allow NULL file for bdrv_get_block_status() 2017-10-26 14:45:57 +02:00
nbd-client.c block/nbd-client: refactor nbd_co_receive_reply 2017-10-12 16:20:27 -05:00
nbd-client.h nbd-client: avoid spurious qio_channel_yield() re-entry 2017-08-23 11:22:15 -05:00
nbd.c nbd: Implement NBD_INFO_BLOCK_SIZE on client 2017-07-14 12:04:42 +02:00
nfs.c qapi: Mechanically convert FOO_lookup[...] to FOO_str(...) 2017-09-04 13:09:13 +02:00
null.c block/null: Remove 'filename' option 2017-08-08 15:19:16 +02:00
parallels.c qapi: drop the sentinel in enum array 2017-09-04 13:09:13 +02:00
qapi.c block: move ThrottleGroup membership to ThrottleGroupMember 2017-09-05 16:47:51 +02:00
qcow2-bitmap.c qcow2: Switch store_bitmap_data() to byte-based iteration 2017-10-06 16:28:58 +02:00
qcow2-cache.c qcow2: add qcow2_cache_discard 2017-09-26 15:00:32 +02:00
qcow2-cluster.c block: convert qcrypto_block_encrypt|decrypt to take bytes offset 2017-10-06 16:30:47 +02:00
qcow2-refcount.c qcow2: truncate the tail of the image file after shrinking the image 2017-10-06 16:30:48 +02:00
qcow2-snapshot.c qcow2: Discard/zero clusters by byte count 2017-05-11 14:28:07 +02:00
qcow2.c block: Allow NULL file for bdrv_get_block_status() 2017-10-26 14:45:57 +02:00
qcow2.h qcow2: truncate the tail of the image file after shrinking the image 2017-10-06 16:30:48 +02:00
qcow.c block: convert qcrypto_block_encrypt|decrypt to take bytes offset 2017-10-06 16:30:47 +02:00
qed-check.c qed: Use DIV_ROUND_UP 2016-06-07 18:19:24 +03:00
qed-cluster.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed-l2-cache.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed-table.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed.c block: rename bdrv_co_drain to bdrv_co_drain_begin 2017-10-13 12:38:41 +01:00
qed.h qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
quorum.c qapi: Change data type of the FOO_lookup generated for enum FOO 2017-09-04 13:09:13 +02:00
raw-format.c block: remove unused bdrv_media_changed 2017-09-04 18:31:13 +02:00
rbd.c qapi: Mechanically convert FOO_lookup[...] to FOO_str(...) 2017-09-04 13:09:13 +02:00
replication.c block: Add reopen_queue to bdrv_child_perm() 2017-09-26 14:46:23 +02:00
sheepdog.c Merge QEMU I/O 2017/09/05 v2 2017-09-05 14:14:33 +01:00
snapshot.c qobject: Use simpler QDict/QList scalar insertion macros 2017-05-09 09:13:51 +02:00
ssh.c util: remove the obsolete non-blocking connect 2017-09-05 13:21:58 +01:00
stream.c block: Make bdrv_is_allocated_above() byte-based 2017-07-10 13:18:07 +02:00
throttle-groups.c block/throttle-groups.c: allocate RestartData on the heap 2017-09-26 14:46:23 +02:00
throttle.c block/throttle.c: add bdrv_co_drain_begin/end callbacks 2017-10-13 12:38:41 +01:00
trace-events block: move trace probes into bdrv_co_preadv|pwritev 2017-08-07 09:39:35 +01:00
vdi.c vdi: make it thread-safe 2017-07-17 11:28:15 +08:00
vhdx-endian.c vhdx: Use QEMU UUID API 2016-09-23 11:42:52 +08:00
vhdx-log.c vhdx: use QEMU_ALIGN_DOWN 2017-08-31 12:29:07 +02:00
vhdx.c block/vhdx: check for offset overflow to bdrv_truncate() 2017-08-08 14:37:00 +02:00
vhdx.h block: vhdx - update PAYLOAD_BLOCK_UNMAPPED value to match 1.00 spec 2014-12-12 15:42:22 +00:00
vmdk.c vmdk: Fix error handling/reporting of vmdk_check 2017-08-08 15:19:16 +02:00
vpc.c vpc: use DIV_ROUND_UP 2017-08-31 12:29:07 +02:00
vvfat.c block: Add reopen_queue to bdrv_child_perm() 2017-09-26 14:46:23 +02:00
vxhs.c qobject: Use simpler QDict/QList scalar insertion macros 2017-05-09 09:13:51 +02:00
win32-aio.c block: explicitly acquire aiocontext in aio callbacks that need it 2017-02-21 11:39:39 +00:00
write-threshold.c block: use bdrv_add_before_write_notifier 2016-10-07 13:34:07 +02:00