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2023-05-30aio: remove aio_disable_external() APIStefan Hajnoczi1-6/+5
All callers now pass is_external=false to aio_set_fd_handler() and aio_set_event_notifier(). The aio_disable_external() API that temporarily disables fd handlers that were registered is_external=true is therefore dead code. Remove aio_disable_external(), aio_enable_external(), and the is_external arguments to aio_set_fd_handler() and aio_set_event_notifier(). The entire test-fdmon-epoll test is removed because its sole purpose was testing aio_disable_external(). Parts of this patch were generated using the following coccinelle (https://coccinelle.lip6.fr/) semantic patch: @@ expression ctx, fd, is_external, io_read, io_write, io_poll, io_poll_ready, opaque; @@ - aio_set_fd_handler(ctx, fd, is_external, io_read, io_write, io_poll, io_poll_ready, opaque) + aio_set_fd_handler(ctx, fd, io_read, io_write, io_poll, io_poll_ready, opaque) @@ expression ctx, notifier, is_external, io_read, io_poll, io_poll_ready; @@ - aio_set_event_notifier(ctx, notifier, is_external, io_read, io_poll, io_poll_ready) + aio_set_event_notifier(ctx, notifier, io_read, io_poll, io_poll_ready) Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20230516190238.8401-21-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30block/export: stop using is_external in vhost-user-blk serverStefan Hajnoczi1-5/+5
vhost-user activity must be suspended during bdrv_drained_begin/end(). This prevents new requests from interfering with whatever is happening in the drained section. Previously this was done using aio_set_fd_handler()'s is_external argument. In a multi-queue block layer world the aio_disable_external() API cannot be used since multiple AioContext may be processing I/O, not just one. Switch to BlockDevOps->drained_begin/end() callbacks. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230516190238.8401-8-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30block/export: wait for vhost-user-blk requests when drainingStefan Hajnoczi1-6/+12
Each vhost-user-blk request runs in a coroutine. When the BlockBackend enters a drained section we need to enter a quiescent state. Currently any in-flight requests race with bdrv_drained_begin() because it is unaware of vhost-user-blk requests. When blk_co_preadv/pwritev()/etc returns it wakes the bdrv_drained_begin() thread but vhost-user-blk request processing has not yet finished. The request coroutine continues executing while the main loop thread thinks it is in a drained section. One example where this is unsafe is for blk_set_aio_context() where bdrv_drained_begin() is called before .aio_context_detached() and .aio_context_attach(). If request coroutines are still running after bdrv_drained_begin(), then the AioContext could change underneath them and they race with new requests processed in the new AioContext. This could lead to virtqueue corruption, for example. (This example is theoretical, I came across this while reading the code and have not tried to reproduce it.) It's easy to make bdrv_drained_begin() wait for in-flight requests: add a .drained_poll() callback that checks the VuServer's in-flight counter. VuServer just needs an API that returns true when there are requests in flight. The in-flight counter needs to be atomic. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230516190238.8401-7-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30util/vhost-user-server: rename refcount to in_flight counterStefan Hajnoczi1-7/+7
The VuServer object has a refcount field and ref/unref APIs. The name is confusing because it's actually an in-flight request counter instead of a refcount. Normally a refcount destroys the object upon reaching zero. The VuServer counter is used to wake up the vhost-user coroutine when there are no more requests. Avoid confusing by renaming refcount and ref/unref to in_flight and inc/dec. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230516190238.8401-6-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-03-27block/export: only acquire AioContext once for vhost_user_server_stop()Stefan Hajnoczi1-4/+1
vhost_user_server_stop() uses AIO_WAIT_WHILE(). AIO_WAIT_WHILE() requires that AioContext is only acquired once. Since blk_exp_request_shutdown() already acquires the AioContext it shouldn't be acquired again in vhost_user_server_stop(). Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20230323145853.1345527-1-stefanha@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-14Do not include "qemu/error-report.h" in headers that do not need itThomas Huth1-0/+1
Include it in the .c files instead that use the error reporting functions. Message-Id: <20230210111931.1115489-1-thuth@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Thomas Huth <thuth@redhat.com>
2023-02-06io: Add support for MSG_PEEK for socket channelmanish.mishra1-1/+1
MSG_PEEK peeks at the channel, The data is treated as unread and the next read shall still return this data. This support is currently added only for socket class. Extra parameter 'flags' is added to io_readv calls to pass extra read flags like MSG_PEEK. Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Suggested-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: manish.mishra <manish.mishra@nutanix.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-05-03util: rename qemu_*block() socket functionsMarc-André Lureau1-2/+2
The qemu_*block() functions are meant to be be used with sockets (the win32 implementation expects SOCKET) Over time, those functions where used with Win32 SOCKET or file-descriptors interchangeably. But for portability, they must only be used with socket-like file-descriptors. FDs can use g_unix_set_fd_nonblocking() instead. Rename the functions with "socket" in the name to prevent bad usages. This is effectively reverting commit f9e8cacc5557e43 ("oslib-posix: rename socket_set_nonblock() to qemu_set_nonblock()"). Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-02-01block/export: Fix vhost-user-blk shutdown with requests in flightKevin Wolf1-0/+22
The vhost-user-blk export runs requests asynchronously in their own coroutine. When the vhost connection goes away and we want to stop the vhost-user server, we need to wait for these coroutines to stop before we can unmap the shared memory. Otherwise, they would still access the unmapped memory and crash. This introduces a refcount to VuServer which is increased when spawning a new request coroutine and decreased before the coroutine exits. The memory is only unmapped when the refcount reaches zero. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20220125151435.48792-1-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-01-12aio-posix: split poll check from ready handlerStefan Hajnoczi1-5/+6
Adaptive polling measures the execution time of the polling check plus handlers called when a polled event becomes ready. Handlers can take a significant amount of time, making it look like polling was running for a long time when in fact the event handler was running for a long time. For example, on Linux the io_submit(2) syscall invoked when a virtio-blk device's virtqueue becomes ready can take 10s of microseconds. This can exceed the default polling interval (32 microseconds) and cause adaptive polling to stop polling. By excluding the handler's execution time from the polling check we make the adaptive polling calculation more accurate. As a result, the event loop now stays in polling mode where previously it would have fallen back to file descriptor monitoring. The following data was collected with virtio-blk num-queues=2 event_idx=off using an IOThread. Before: 168k IOPS, IOThread syscalls: 9837.115 ( 0.020 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 16, iocbpp: 0x7fcb9f937db0) = 16 9837.158 ( 0.002 ms): IO iothread1/620155 write(fd: 103, buf: 0x556a2ef71b88, count: 8) = 8 9837.161 ( 0.001 ms): IO iothread1/620155 write(fd: 104, buf: 0x556a2ef71b88, count: 8) = 8 9837.163 ( 0.001 ms): IO iothread1/620155 ppoll(ufds: 0x7fcb90002800, nfds: 4, tsp: 0x7fcb9f1342d0, sigsetsize: 8) = 3 9837.164 ( 0.001 ms): IO iothread1/620155 read(fd: 107, buf: 0x7fcb9f939cc0, count: 512) = 8 9837.174 ( 0.001 ms): IO iothread1/620155 read(fd: 105, buf: 0x7fcb9f939cc0, count: 512) = 8 9837.176 ( 0.001 ms): IO iothread1/620155 read(fd: 106, buf: 0x7fcb9f939cc0, count: 512) = 8 9837.209 ( 0.035 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 32, iocbpp: 0x7fca7d0cebe0) = 32 174k IOPS (+3.6%), IOThread syscalls: 9809.566 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0cdd62be0) = 32 9809.625 ( 0.001 ms): IO iothread1/623061 write(fd: 103, buf: 0x5647cfba5f58, count: 8) = 8 9809.627 ( 0.002 ms): IO iothread1/623061 write(fd: 104, buf: 0x5647cfba5f58, count: 8) = 8 9809.663 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0d0388b50) = 32 Notice that ppoll(2) and eventfd read(2) syscalls are eliminated because the IOThread stays in polling mode instead of falling back to file descriptor monitoring. As usual, polling is not implemented on Windows so this patch ignores the new io_poll_read() callback in aio-win32.c. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Message-id: 20211207132336.36627-2-stefanha@redhat.com [Fixed up aio_set_event_notifier() calls in tests/unit/test-fdmon-epoll.c added after this series was queued. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: move header to include/Stefan Hajnoczi1-1/+1
Headers used by other subsystems are located in include/. Also add the vhost-user-server and vhost-user-blk-server headers to MAINTAINERS. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-13-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23block/export: convert vhost-user-blk server to block export APIStefan Hajnoczi1-1/+9
Use the new QAPI block exports API instead of defining our own QOM objects. This is a large change because the lifecycle of VuBlockDev needs to follow BlockExportDriver. QOM properties are replaced by QAPI options objects. VuBlockDev is renamed VuBlkExport and contains a BlockExport field. Several fields can be dropped since BlockExport already has equivalents. The file names and meson build integration will be adjusted in a future patch. libvhost-user should probably be built as a static library that is linked into QEMU instead of as a .c file that results in duplicate compilation. The new command-line syntax is: $ qemu-storage-daemon \ --blockdev file,node-name=drive0,filename=test.img \ --export vhost-user-blk,node-name=drive0,id=export0,unix-socket=/tmp/vhost-user-blk.sock Note that unix-socket is optional because we may wish to accept chardevs too in the future. Markus noted that supported address families are not explicit in the QAPI schema. It is unlikely that support for more address families will be added since file descriptor passing is required and few address families support it. If a new address family needs to be added, then the QAPI 'features' syntax can be used to advertize them. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Markus Armbruster <armbru@redhat.com> Message-id: 20200924151549.913737-12-stefanha@redhat.com [Skip test on big-endian host architectures because this device doesn't support them yet (as already mentioned in a code comment). --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: rework vu_client_trip() coroutine lifecycleStefan Hajnoczi1-107/+136
The vu_client_trip() coroutine is leaked during AioContext switching. It is also unsafe to destroy the vu_dev in panic_cb() since its callers still access it in some cases. Rework the lifecycle to solve these safety issues. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-10-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: check EOF when reading payloadStefan Hajnoczi1-2/+4
Unexpected EOF is an error that must be reported. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-9-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: fix memory leak in vu_message_read()Stefan Hajnoczi1-27/+23
fds[] is leaked when qio_channel_readv_full() fails. Use vmsg->fds[] instead of keeping a local fds[] array. Then we can reuse goto fail to clean up fds. vmsg->fd_num must be zeroed before the loop to make this safe. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-8-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: drop unused DevicePanicNotifierStefan Hajnoczi1-6/+0
The device panic notifier callback is not used. Drop it. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-7-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: drop unnecessary watch deletionStefan Hajnoczi1-15/+4
Explicitly deleting watches is not necessary since libvhost-user calls remove_watch() during vu_deinit(). Add an assertion to check this though. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-5-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: drop unnecessary QOM castStefan Hajnoczi1-1/+1
We already have access to the value with the correct type (ioc and sioc are the same QIOChannel). Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-4-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: s/fileds/fields/ typo fixStefan Hajnoczi1-1/+1
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-23util/vhost-user-server: generic vhost user serverCoiby Xu1-0/+428
Sharing QEMU devices via vhost-user protocol. Only one vhost-user client can connect to the server one time. Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Coiby Xu <coiby.xu@gmail.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-id: 20200918080912.321299-4-coiby.xu@gmail.com [Fixed size_t %lu -> %zu format string compiler error. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
generated by cgit v1.1 at 2025-01-20 16:13:18 +0000