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2019-02-28dataplane/xen-block: remove dead codePaul Durrant1-4/+1
The if() statement is clearly bogus (dead code which should have been cleaned up when grant mapping was removed). Spotted by Coverity: CID 1398635 While in the neighbourhood, add a missing 'fall through' annotation. Reported-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony PERARD <anthony.perard@citrix.com> Message-Id: <20190215162533.19475-2-paul.durrant@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-02-04xen-block: handle resize callbackPaul Durrant1-3/+1
Some frontend drivers will handle dynamic resizing of PV disks, so set up the BlockDevOps resize_cb() method during xen_block_realize() to allow this to be done. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Reviewed-by: Anthony PERARD <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen-block: avoid repeated memory allocationTim Smith1-5/+9
The xen-block dataplane currently allocates memory to hold the data for each request as that request is used, and frees it afterwards. Because it requires page-aligned blocks, this interacts poorly with non-page- aligned allocations and balloons the heap. Instead, allocate the maximum possible buffer size required for the protocol, which is BLKIF_MAX_SEGMENTS_PER_REQUEST (currently 11) pages when the request structure is created, and keep that buffer until it is destroyed. Since the requests are re-used via a free list, this should actually improve memory usage. Signed-off-by: Tim Smith <tim.smith@citrix.com> Re-based and commit comment adjusted. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony PERARD <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen-block: improve response latencyTim Smith1-38/+18
If the I/O ring is full, the guest cannot send any more requests until some responses are sent. Only sending all available responses just before checking for new work does not leave much time for the guest to supply new work, so this will cause stalls if the ring gets full. Also, not completing reads as soon as possible adds latency to the guest. To alleviate that, complete IO requests as soon as they come back. xen_block_send_response() already returns a value indicating whether a notify should be sent, which is all the batching we need. Signed-off-by: Tim Smith <tim.smith@citrix.com> Re-based and commit comment adjusted. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony PERARD <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen-block: improve batching behaviourTim Smith1-0/+35
When I/O consists of many small requests, performance is improved by batching them together in a single io_submit() call. When there are relatively few requests, the extra overhead is not worth it. This introduces a check to start batching I/O requests via blk_io_plug()/ blk_io_unplug() in an amount proportional to the number which were already in flight at the time we started reading the ring. Signed-off-by: Tim Smith <tim.smith@citrix.com> Re-based and commit comment adjusted. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony PERARD <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen: purge 'blk' and 'ioreq' from function names in dataplane/xen-block.cPaul Durrant1-44/+46
This is a purely cosmetic patch that purges remaining use of 'blk' and 'ioreq' in local function names, and then makes sure all functions are prefixed with 'xen_block_'. No functional change. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen: remove 'ioreq' struct/varable/field names from dataplane/xen-block.cPaul Durrant1-154/+156
This is a purely cosmetic patch that purges the name 'ioreq' from struct, variable and field names. (This name has been problematic for a long time as 'ioreq' is the name used for generic I/O requests coming from Xen). The patch replaces 'struct ioreq' with a new 'XenBlockRequest' type and 'ioreq' field/variable names with 'request', and then does necessary fix-up to adhere to coding style. Function names are not modified by this patch. They will be dealt with in a subsequent patch. No functional change. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen: remove 'XenBlkDev' and 'blkdev' names from dataplane/xen-blockPaul Durrant2-171/+183
This is a purely cosmetic patch that substitutes the old 'struct XenBlkDev' name with 'XenBlockDataPlane' and 'blkdev' field/variable names with 'dataplane', and then does necessary fix-up to adhere to coding style. No functional change. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen: add header and build dataplane/xen-block.cPaul Durrant3-100/+286
This patch adds the transformations necessary to get dataplane/xen-block.c to build against the new XenBus/XenDevice framework. MAINTAINERS is also updated due to the introduction of dataplane/xen-block.h. NOTE: Existing data structure names are retained for the moment. These will be modified by subsequent patches. A typedef for XenBlockDataPlane has been added to the header (based on the old struct XenBlkDev name for the moment) so that the old names don't need to leak out of the dataplane code. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Reviewed-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen: remove unnecessary code from dataplane/xen-block.cPaul Durrant1-406/+23
Not all of the code duplicated from xen_disk.c is required as the basis for the new dataplane implementation so this patch removes extraneous code, along with the legacy #includes and calls to the legacy xen_pv_printf() function. Error messages are changed to be reported using error_report(). NOTE: The code is still not yet built. Further transformations will be required to make it correctly interface to the new XenBus/XenDevice framework. They will be delivered in a subsequent patch. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14xen: duplicate xen_disk.c as basis of dataplane/xen-block.cPaul Durrant1-0/+1019
The new xen-block XenDevice implementation requires the same core dataplane as the legacy xen_disk implementation it will eventually replace. This patch therefore copies the legacy xen_disk.c source module into a new dataplane/xen-block.c source module as the basis for the new dataplane and adjusts the MAINTAINERS file accordingly. NOTE: The duplicated code is not yet built. It is simply put into place by this patch (just fixing style violations) such that the modifications that will need to be made to the code are not conflated with code movement, thus making review harder. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2018-06-28Replace '-enable-kvm' with '-accel kvm' in docs and help textsThomas Huth1-2/+2
The preferred way to select the KVM accelerator is to use "-accel kvm" these days, so let's be consistent in our documentation and help texts. Signed-off-by: Thomas Huth <thuth@redhat.com> Message-Id: <1528866321-23886-3-git-send-email-thuth@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01hw: Do not include "sysemu/block-backend.h" if it is not necessaryPhilippe Mathieu-Daudé1-1/+0
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 Hajnoczi1-7/+17
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 Lopez1-2/+13
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 Hammer1-0/+2
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 Zhongyi2-6/+8
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-Daudé1-1/+1
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 Zheng1-2/+2
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 Hajnoczi1-1/+0
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. Berrange1-0/+6
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 Bonzini1-3/+1
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 Bonzini2-31/+48
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 Bonzini1-1/+1
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 jin1-4/+2
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 Hajnoczi1-16/+34
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 Hajnoczi2-3/+3
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 Hajnoczi1-6/+23
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 Huck1-10/+2
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 Huck1-3/+11
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 Zheng1-63/+0
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 Bonzini1-4/+3
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. Tsirkin1-0/+13
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 Bonzini1-4/+3
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 Armbruster1-0/+1
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 Bonzini2-100/+13
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 Bonzini1-12/+9
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 Bonzini1-1/+2
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 Bonzini1-6/+5
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 Reitz1-18/+59
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 Maydell1-0/+1
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 Armbruster1-6/+2
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 Zheng1-1/+1
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 Zheng1-13/+2
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 Zheng1-3/+2
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 Zheng1-2/+4
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 Bonzini1-1/+1
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 Bonzini1-2/+1
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 Huck1-1/+3
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 Lieven1-4/+4
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>
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