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2018-06-01hw: Do not include "sysemu/block-backend.h" if it is not necessaryPhilippe Mathieu-Daudé
Remove those unneeded includes to speed up the compilation process a little bit. (Continue 7eceff5b5a1fa cleanup) Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-Id: <20180528232719.4721-13-f4bug@amsat.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-08virtio-blk: fix race between .ioeventfd_stop() and vq handlerStefan Hajnoczi
If the main loop thread invokes .ioeventfd_stop() just as the vq handler function begins in the IOThread then the handler may lose the race for the AioContext lock. By the time the vq handler is able to acquire the AioContext lock the ioeventfd has already been removed and the handler isn't supposed to run anymore! Use the new aio_wait_bh_oneshot() function to perform ioeventfd removal from within the IOThread. This way no races with the vq handler are possible. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20180307144205.20619-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-03-08virtio-blk: dataplane: Don't batch notifications if EVENT_IDX is presentSergio Lopez
Commit 5b2ffbe4d99843fd8305c573a100047a8c962327 ("virtio-blk: dataplane: notify guest as a batch") deferred guest notification to a BH in order batch notifications, with purpose of avoiding flooding the guest with interruptions. This optimization came with a cost. The average latency perceived in the guest is increased by a few microseconds, but also when multiple IO operations finish at the same time, the guest won't be notified until all completions from each operation has been run. On the contrary, virtio-scsi issues the notification at the end of each completion. On the other hand, nowadays we have the EVENT_IDX feature that allows a better coordination between QEMU and the Guest OS to avoid sending unnecessary interruptions. With this change, virtio-blk/dataplane only batches notifications if the EVENT_IDX feature is not present. Some numbers obtained with fio (ioengine=sync, iodepth=1, direct=1): - Test specs: * fio-3.4 (ioengine=sync, iodepth=1, direct=1) * qemu master * virtio-blk with a dedicated iothread (default poll-max-ns) * backend: null_blk nr_devices=1 irqmode=2 completion_nsec=280000 * 8 vCPUs pinned to isolated physical cores * Emulator and iothread also pinned to separate isolated cores * variance between runs < 1% - Not patched * numjobs=1: lat_avg=327.32 irqs=29998 * numjobs=4: lat_avg=337.89 irqs=29073 * numjobs=8: lat_avg=342.98 irqs=28643 - Patched: * numjobs=1: lat_avg=323.92 irqs=30262 * numjobs=4: lat_avg=332.65 irqs=29520 * numjobs=8: lat_avg=335.54 irqs=29323 Signed-off-by: Sergio Lopez <slp@redhat.com> Message-id: 20180307114459.26636-1-slp@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-02-08virtio: remove event notifier cleanup call on de-assignGal Hammer
The virtio_bus_set_host_notifier function no longer calls event_notifier_cleanup when a event notifier is removed. The commit updates the code to match the new behavior and calls virtio_bus_cleanup_host_notifier after the notifier was de-assign and no longer in use. This change is a preparation to allow executing the virtio_bus_set_host_notifier function in a memory region transaction. Signed-off-by: Gal Hammer <ghammer@redhat.com> Reviewed-by: Greg Kurz <groug@kaod.org> Tested-by: Greg Kurz <groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-12-19hw/block: Fix the return typeMao Zhongyi
When the function no success value to transmit, it usually make the function return void. It has turned out not to be a success, because it means that the extra local_err variable and error_propagate() will be needed. It leads to cumbersome code, therefore, transmit success/ failure in the return value is worth. So fix the return type of blkconf_apply_backend_options(), blkconf_geometry() and virtio_blk_data_plane_create() to avoid it. Cc: John Snow <jsnow@redhat.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Max Reitz <mreitz@redhat.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: ac0edc1fc70c4457e5cec94405eb7d1f89f9c2c1.1511317952.git.maozy.fnst@cn.fujitsu.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-07-31docs: fix broken paths to docs/devel/tracing.txtPhilippe Mathieu-Daudé
With the move of some docs/ to docs/devel/ on ac06724a71, no references were updated. Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-02-17virtio: Report real progress in VQ aio poll handlerFam Zheng
In virtio_queue_host_notifier_aio_poll, not all "!virtio_queue_empty()" cases are making true progress. Currently the offending one is virtio-scsi event queue, whose handler does nothing if no event is pending. As a result aio_poll() will spin on the "non-empty" VQ and take 100% host CPU. Fix this by reporting actual progress from virtio queue aio handlers. Reported-by: Ed Swierk <eswierk@skyportsystems.com> Signed-off-by: Fam Zheng <famz@redhat.com> Tested-by: Ed Swierk <eswierk@skyportsystems.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-31trace: clean up trace-events filesStefan Hajnoczi
There are a number of unused trace events that scripts/cleanup-trace-events.pl finds. The "hw/vfio/pci-quirks.c" filename was typoed and "qapi/qapi-visit-core.c" was missing the qapi/ directory prefix. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20170126171613.1399-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-31trace: move hw/block/dataplane events to correct subdirDaniel P. Berrange
The trace-events for a given source file should generally always live in the same directory as the source file. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170125161417.31949-3-berrange@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-11-18virtio: set ISR on dataplane notificationsPaolo Bonzini
Dataplane has been omitting forever the step of setting ISR when an interrupt is raised. This caused little breakage, because the specification actually says that ISR may not be updated in MSI mode. Some versions of the Windows drivers however didn't clear MSI mode correctly, and proceeded using polling mode (using ISR, not the used ring index!) for crashdump and hibernation. If it were just crashdump and hibernation it would not be a big deal, but recent releases of Windows do not really shut down, but rather log out and hibernate to make the next startup faster. Hence, this manifested as a more serious hang during shutdown with e.g. Windows 8.1 and virtio-win 1.8.0 RPMs. Newer versions fixed this, while older versions do not use MSI at all. The failure has always been there for virtio dataplane, but it became visible after commits 9ffe337 ("virtio-blk: always use dataplane path if ioeventfd is active", 2016-10-30) and ad07cd6 ("virtio-scsi: always use dataplane path if ioeventfd is active", 2016-10-30) made virtio-blk and virtio-scsi always use the dataplane code under KVM. The good news therefore is that it was not a bug in the patches---they were doing exactly what they were meant for, i.e. shake out remaining dataplane bugs. The fix is not hard, so it's worth arranging for the broken drivers. The virtio_should_notify+event_notifier_set pair that is common to virtio-blk and virtio-scsi dataplane is replaced with a new public function virtio_notify_irqfd that also sets ISR. The irqfd emulation code now need not set ISR anymore, so virtio_irq is removed. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com> Tested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30virtio-blk: always use dataplane path if ioeventfd is activePaolo Bonzini
Override start_ioeventfd and stop_ioeventfd to start/stop the whole dataplane logic. This has some positive side effects: - no need anymore for virtio_add_queue_aio (i.e. a revert of commit 0ff841f6d138904d514efa1d885bcaf54583852d) - no need anymore to switch from generic ioeventfd handlers to dataplane It detects some errors better: $ qemu-system-x86_64 -object iothread,id=io \ -drive id=null,file=null-aio://,if=none,format=raw \ -device virtio-blk-pci,ioeventfd=off,iothread=io,drive=null qemu-system-x86_64: -device virtio-blk-pci,ioeventfd=off,iothread=io,drive=null: ioeventfd is required for iothread while previously it would have started just fine. Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30virtio: move ioeventfd_started flag to VirtioBusStatePaolo Bonzini
This simplifies the code and removes the ioeventfd_started and ioeventfd_set_started callback. The only difference is in how virtio-ccw handles an error---it doesn't disable ioeventfd forever anymore. It was the only backend to do so, and if desired this behavior should be implemented in virtio-bus.c. Instead of ioeventfd_started, the ioeventfd_assign callback now determines whether the virtio bus supports host notifiers. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-18virtio-blk: dataplane cleanupCao jin
No need duplicate the judgment, there is one in function entry. Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Max Reitz <mreitz@redhat.com> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1468814749-14510-1-git-send-email-caoj.fnst@cn.fujitsu.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28virtio-blk: dataplane multiqueue supportStefan Hajnoczi
Monitor ioeventfds for all virtqueues in the device's AioContext. This is not true multiqueue because requests from all virtqueues are processed in a single IOThread. In the future it will be possible to use multiple IOThreads when the QEMU block layer supports multiqueue. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1466511196-12612-7-git-send-email-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28virtio-blk: tell dataplane which vq to notifyStefan Hajnoczi
Let the virtio_blk_data_plane_notify() caller decide which virtqueue to notify. This will allow the function to be used with multiqueue. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1466511196-12612-4-git-send-email-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28virtio-blk: multiqueue batch notifyStefan Hajnoczi
The batch notification BH needs to know which virtqueues to notify when multiqueue is enabled. Use a bitmap to track the virtqueues with pending notifications. At this point there is only one virtqueue so hard-code virtqueue index 0. A later patch will switch to real virtqueue indices. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1466511196-12612-3-git-send-email-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-24virtio-bus: remove old set_host_notifier callbackCornelia Huck
All users have been converted to the new ioevent callbacks. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-06-24virtio-bus: have callers tolerate new host notifier apiCornelia Huck
Have vhost and dataplane use the new api for transports that have been converted. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-06-07virtio-blk: Remove op blocker for dataplaneFam Zheng
Block layer is prepared to unspecialize dataplane, an evidence is this almost complete list of unblocked operations. It has all types except two (actually three if DATAPLANE itself counts but blockdev.c makes sure attaching twice is not possible): MIRROR_TARGET and BACKUP_TARGET. blockdev-mirror refuses to start if target is attached, so the first is not a problem. By removing BACKUP_TARGET, blockdev-backup will become permissive to write to a virtio-blk dataplane disk, but that is not worse than non-dataplane given the latter is already possible. In either case, blockdev.c always checks the target and source are on the same AioContext, or bring them together if possible. Signed-off-by: Fam Zheng <famz@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Message-id: 1463969978-24970-4-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-04-07virtio: merge virtio_queue_aio_set_host_notifier_handler with ↵Paolo Bonzini
virtio_queue_set_aio Eliminating the reentrancy is actually a nice thing that we can do with the API that Michael proposed, so let's make it first class. This also hides the complex assign/set_handler conventions from callers of virtio_queue_aio_set_host_notifier_handler, which in fact was always called with assign=true. Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07virtio-blk: use aio handler for data planeMichael S. Tsirkin
In addition to handling IO in vcpu thread and in io thread, dataplane introduces yet another mode: handling it by AioContext. This reuses the same handler as previous modes, which triggers races as these were not designed to be reentrant. Use a separate handler just for aio, and disable regular handlers when dataplane is active. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07virtio-blk: fix disabled modePaolo Bonzini
We must not call virtio_blk_data_plane_notify if dataplane is disabled: we would hit a segmentation fault in notify_guest_bh as s->guest_notifier has not been setup and is NULL. Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-22include/qemu/osdep.h: Don't include qapi/error.hMarkus Armbruster
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the Error typedef. Since then, we've moved to include qemu/osdep.h everywhere. Its file comment explains: "To avoid getting into possible circular include dependencies, this file should not include any other QEMU headers, with the exceptions of config-host.h, compiler.h, os-posix.h and os-win32.h, all of which are doing a similar job to this file and are under similar constraints." qapi/error.h doesn't do a similar job, and it doesn't adhere to similar constraints: it includes qapi-types.h. That's in excess of 100KiB of crap most .c files don't actually need. Add the typedef to qemu/typedefs.h, and include that instead of qapi/error.h. Include qapi/error.h in .c files that need it and don't get it now. Include qapi-types.h in qom/object.h for uint16List. Update scripts/clean-includes accordingly. Update it further to match reality: replace config.h by config-target.h, add sysemu/os-posix.h, sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h comment quoted above similarly. This reduces the number of objects depending on qapi/error.h from "all of them" to less than a third. Unfortunately, the number depending on qapi-types.h shrinks only a little. More work is needed for that one. Signed-off-by: Markus Armbruster <armbru@redhat.com> [Fix compilation without the spice devel packages. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-25virtio-blk: do not use vring in dataplanePaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-25virtio-blk: fix "disabled data plane" modePaolo Bonzini
In disabled mode, virtio-blk dataplane seems to be enabled, but flow actually goes through the normal virtio path. This patch simplifies a bit the handling of disabled mode. In disabled mode, virtio_blk_handle_output might be called even if s->dataplane is not NULL. This is a bit tricky, because the current check for s->dataplane will always trigger, causing a continuous stream of calls to virtio_blk_data_plane_start. Unfortunately, these calls will not do anything. To fix this, set the "started" flag even in disabled mode, and skip virtio_blk_data_plane_start if the started flag is true. The resulting changes also prepare the code for the next patch, were virtio-blk dataplane will reuse the same virtio_blk_handle_output function as "regular" virtio-blk. Because struct VirtIOBlockDataPlane is opaque in virtio-blk.c, we have to move s->dataplane->started inside struct VirtIOBlock. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-25vring: make vring_enable_notification return voidPaolo Bonzini
Make the API more similar to the regular virtqueue API. This will help when modifying the code to not use vring.c anymore. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-06virtio: move allocation to virtqueue_pop/vring_popPaolo Bonzini
The return code of virtqueue_pop/vring_pop is unused except to check for errors or 0. We can thus easily move allocation inside the functions and just return a pointer to the VirtQueueElement. The advantage is that we will be able to allocate only the space that is needed for the actual size of the s/g list instead of the full VIRTQUEUE_MAX_SIZE items. Currently VirtQueueElement takes about 48K of memory, and this kind of allocation puts a lot of stress on malloc. By cutting the size by two or three orders of magnitude, malloc can use much more efficient algorithms. The patch is pretty large, but changes to each device are testable more or less independently. Splitting it would mostly add churn. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-02-02virtio-blk: Functions for op blocker managementMax Reitz
Put the code for setting up and removing op blockers into an own function, respectively. Then, we can invoke those functions whenever a BDS is removed from an virtio-blk BB or inserted into it. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-20block: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-13error: Use error_prepend() where it makes obvious senseMarkus Armbruster
Done with this Coccinelle semantic patch @@ expression FMT, E1, E2; expression list ARGS; @@ - error_setg(E1, FMT, ARGS, error_get_pretty(E2)); + error_propagate(E1, E2);/*###*/ + error_prepend(E1, FMT/*@@@*/, ARGS); followed by manual cleanup, first because I can't figure out how to make Coccinelle transform strings, and second to get rid of now superfluous error_propagate(). We now use or propagate the original error whole instead of just its message obtained with error_get_pretty(). This avoids suppressing its hint (see commit 50b7b00), but I can't see how the errors touched in this commit could come with hints. It also improves the message printed with &error_abort when we screw up (see commit 1e9b65b). Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-07block: Rename BLOCK_OP_TYPE_MIRROR to BLOCK_OP_TYPE_MIRROR_SOURCEFam Zheng
It's necessary to distinguish source and target before we can add blockdev-mirror, because we would want a concrete type of operation to check on target bs before starting. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1450932306-13717-2-git-send-email-famz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-12-07virtio-blk: Drop x-data-plane optionFam Zheng
The official way of enabling dataplane is through the "iothread" property that references an iothread object created by "-object iothread". Since the old "x-data-plane=on" way now even crashes, it's probably easier to just drop it: $ qemu-system-x86_64 -drive file=null-co://,id=d0,if=none \ -device virtio-blk-pci,drive=d0,x-data-plane=on ERROR:/home/fam/work/qemu/qom/object.c:1515: object_get_canonical_path_component: assertion failed: (obj->parent != NULL) Aborted Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1449485967-19240-1-git-send-email-famz@redhat.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-10-23dataplane: Mark host notifiers' client type as "external"Fam Zheng
They will be excluded by type in the nested event loops in block layer, so that unwanted events won't be processed there. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-10-23aio: Add "is_external" flag for event handlersFam Zheng
All callers pass in false, and the real external ones will switch to true in coming patches. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-07-29virtio-blk-dataplane: delete bottom half before the AioContext is freedPaolo Bonzini
Other uses of aio_bh_new are safe as long as all scheduled bottom halves are run before an iothread is destroyed, which bdrv_drain will ensure: - archipelago_finish_aiocb: BH deletes itself - inject_error: BH deletes itself - blkverify_aio_bh: BH deletes itself - abort_aio_request: BH deletes itself - curl_aio_readv: BH deletes itself - gluster_finish_aiocb: BH deletes itself - bdrv_aio_rw_vector: BH deletes itself - bdrv_co_maybe_schedule_bh: BH deletes itself - iscsi_schedule_bh, iscsi_co_generic_cb: BH deletes itself - laio_attach_aio_context: deleted in laio_detach_aio_context, called through bdrv_detach_aio_context before deleting the iothread - nfs_co_generic_cb: BH deletes itself - null_aio_common: BH deletes itself - qed_aio_complete: BH deletes itself - rbd_finish_aiocb: BH deletes itself - dma_blk_cb: BH deletes itself - virtio_blk_dma_restart_cb: BH deletes itself - qemu_bh_new: main loop AioContext is never destroyed - test-aio.c: bh_delete_cb deletes itself, otherwise deleted in the same function that calls aio_bh_new Reported-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1438101249-25166-2-git-send-email-pbonzini@redhat.com Message-Id: <1438086628-13000-1-git-send-email-pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-04-08virtio-blk: correctly dirty guest memoryPaolo Bonzini
After qemu_iovec_destroy, the QEMUIOVector's size is zeroed and the zero size ultimately is used to compute virtqueue_push's len argument. Therefore, reads from virtio-blk devices did not migrate their results correctly. (Writes were okay). Save the size in virtio_blk_handle_request, and use it when the request is completed. Based on a patch by Wen Congyang. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Tested-by: Li Zhijian <lizhijian@cn.fujitsu.com> Message-id: 1427997044-392-1-git-send-email-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-16dataplane: endianness-aware accessesCornelia Huck
The vring.c code currently assumes that guest and host endianness match, which is not true for a number of cases: - emulating targets with a different endianness than the host - bi-endian targets, where the correct endianness depends on the virtio device - upcoming support for the virtio-1 standard mandates little-endian accesses even for big-endian targets and hosts Make sure to use accessors that depend on the virtio device. Note that dataplane now needs to be built per-target. Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Fam Zheng <famz@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Tested-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1422289602-17874-2-git-send-email-cornelia.huck@de.ibm.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-06virtio-blk: introduce multireadPeter Lieven
this patch finally introduces multiread support to virtio-blk. While multiwrite support was there for a long time, read support was missing. The complete merge logic is moved into virtio-blk.c which has been the only user of request merging ever since. This is required to be able to merge chunks of requests and immediately invoke callbacks for those requests. Secondly, this is required to switch to direct invocation of coroutines which is planned at a later stage. The following benchmarks show the performance of running fio with 4 worker threads on a local ram disk. The numbers show the average of 10 test runs after 1 run as warmup phase. | 4k | 64k | 4k MB/s | rd seq | rd rand | rd seq | rd rand | wr seq | wr rand --------------+--------+---------+--------+---------+--------+-------- master | 1221 | 1187 | 4178 | 4114 | 1745 | 1213 multiread | 1829 | 1189 | 4639 | 4110 | 1894 | 1216 Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-13block: Split BLOCK_OP_TYPE_COMMIT to BLOCK_OP_TYPE_COMMIT_{SOURCE, TARGET}Fam Zheng
Like BLOCK_OP_TYPE_BACKUP_SOURCE and BLOCK_OP_TYPE_BACKUP_TARGET, block-commit involves two asymmetric devices. This change is not user-visible (yet), because commit only works with device names. But once we enable backing reference in blockdev-add, or specifying node-name in block-commit command, we don't want the user to start two commit jobs on the same backing chain, which will corrupt things because of the final bdrv_swap. Before we have per category blockers, splitting this type is still better. [Resolved virtio-blk dataplane conflict by replacing BLOCK_OP_TYPE_COMMIT with both BLOCK_OP_TYPE_COMMIT_{SOURCE, TARGET}. They are safe since the block job runs in the same AioContext as the dataplane IOThread. --Stefan] Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-10blockdev: acquire AioContext in QMP 'transaction' actionsStefan Hajnoczi
The transaction QMP command performs operations atomically on a group of drives. This command needs to acquire AioContext in order to work safely when virtio-blk dataplane IOThreads are accessing drives. The transactional nature of the command means that actions are split into prepare, commit, abort, and clean functions. Acquire the AioContext in prepare and don't release it until one of the other functions is called. This prevents the IOThread from running the AioContext before the transaction has completed. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1416566940-4430-4-git-send-email-stefanha@redhat.com Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10blockdev: acquire AioContext in change-backing-fileStefan Hajnoczi
Add dataplane support to the change-backing-file QMP commands. By acquiring the AioContext we avoid race conditions with the dataplane thread which may also be accessing the BlockDriverState. Note that this command operates on both bs and a node in its chain (image_bs). The bdrv_chain_contains(bs, image_bs) check guarantees that bs and image_bs are in the same AioContext. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10blockdev: acquire AioContext in eject, change, and block_passwdStefan Hajnoczi
By acquiring the AioContext we avoid race conditions with the dataplane thread which may also be accessing the BlockDriverState. Fix up eject, change, and block_passwd in a single patch because qmp_eject() and qmp_change_blockdev() both call eject_device(). Also fix block_passwd while we're tackling a command that takes a block encryption password. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10blockdev: acquire AioContext in blockdev-snapshot-delete-internal-syncStefan Hajnoczi
Add dataplane support to the blockdev-snapshot-delete-internal-sync QMP command. By acquiring the AioContext we avoid race conditions with the dataplane thread which may also be accessing the BlockDriverState. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-11-03block: declare blockjobs and dataplane friends!Stefan Hajnoczi
Now that blockjobs use AioContext they are safe for use with dataplane. Unblock them! Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1413889440-32577-12-git-send-email-stefanha@redhat.com
2014-10-20hw: Convert from BlockDriverState to BlockBackend, mostlyMarkus Armbruster
Device models should access their block backends only through the block-backend.h API. Convert them, and drop direct includes of inappropriate headers. Just four uses of BlockDriverState are left: * The Xen paravirtual block device backend (xen_disk.c) opens images itself when set up via xenbus, bypassing blockdev.c. I figure it should go through qmp_blockdev_add() instead. * Device model "usb-storage" prompts for keys. No other device model does, and this one probably shouldn't do it, either. * ide_issue_trim_cb() uses bdrv_aio_discard() instead of blk_aio_discard() because it fishes its backend out of a BlockAIOCB, which has only the BlockDriverState. * PC87312State has an unused BlockDriverState[] member. The next two commits take care of the latter two. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20virtio-blk: Rename VirtIOBlkConf variables to confMarkus Armbruster
This is consistent with how VirtIOFOOConf variables are named elsewhere, and makes blk available for BlockBackend variables. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-11dataplane: fix virtio_blk_data_plane_create() op blocker error pathStefan Hajnoczi
Commit 3718d8ab65f68de2acccbe6a315907805f54e3cc ("block: Replace in_use with operation blocker") broke the error path because it consumed local_err instead of propagating it. The caller has no way to know that the function failed. This caused virtio-blk to start "successfully" even though there was a fatal dataplane error. Steps to reproduce: $ qemu-system-x86_64 -enable-kvm -object iothread,id=iothread0 \ -drive if=none,id=drive0,file=a.img \ (qemu) drive_mirror drive0 /tmp/foo.img (qemu) device_add virtio-blk-pci,iothread=iothread0,drive=drive0 Expected result: Since the mirror block job is using drive0 it is not possible to start virtio-blk data-plane. device_add fails and the PCI adapter is not added. Actual result: device_add completes and the PCI adapter is added. Cc: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-29virtio-blk: allow drive_del with dataplaneStefan Hajnoczi
Now that drive_del acquires the AioContext we can safely allow deleting the drive. As with non-dataplane mode, all I/Os submitted by the guest after drive_del will return EIO. This patch makes hot unplug work with virtio-blk dataplane. Previously drive_del reported an error because the device was busy. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-20virtio-blk: allow block_resize with dataplaneStefan Hajnoczi
Now that block_resize acquires the AioContext we can safely allow resizing the disk. Reported-by: Andrey Korolyov <andrey@xdel.ru> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-15dataplane: stop trying on notifier errorCornelia Huck
If we fail to set up guest or host notifiers, there's no use trying again every time the guest kicks, so disable dataplane in that case. Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>