From 73fd282e7b6dd4e4ea1c3bbb3d302c8db51e4ccf Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Thu, 5 Mar 2020 17:08:04 +0000 Subject: aio-posix: add io_uring fd monitoring implementation The recent Linux io_uring API has several advantages over ppoll(2) and epoll(2). Details are given in the source code. Add an io_uring implementation and make it the default on Linux. Performance is the same as with epoll(7) but later patches add optimizations that take advantage of io_uring. It is necessary to change how aio_set_fd_handler() deals with deleting AioHandlers since removing monitored file descriptors is asynchronous in io_uring. fdmon_io_uring_remove() marks the AioHandler deleted and aio_set_fd_handler() will let it handle deletion in that case. Signed-off-by: Stefan Hajnoczi Link: https://lore.kernel.org/r/20200305170806.1313245-6-stefanha@redhat.com Message-Id: <20200305170806.1313245-6-stefanha@redhat.com> --- include/block/aio.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/block/aio.h') diff --git a/include/block/aio.h b/include/block/aio.h index bd76b08f1a..83fc9b844d 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -14,6 +14,9 @@ #ifndef QEMU_AIO_H #define QEMU_AIO_H +#ifdef CONFIG_LINUX_IO_URING +#include +#endif #include "qemu/queue.h" #include "qemu/event_notifier.h" #include "qemu/thread.h" @@ -96,6 +99,8 @@ struct BHListSlice { QSIMPLEQ_ENTRY(BHListSlice) next; }; +typedef QSLIST_HEAD(, AioHandler) AioHandlerSList; + struct AioContext { GSource source; @@ -181,6 +186,10 @@ struct AioContext { * locking. */ struct LuringState *linux_io_uring; + + /* State for file descriptor monitoring using Linux io_uring */ + struct io_uring fdmon_io_uring; + AioHandlerSList submit_list; #endif /* TimerLists for calling timers - one per clock type. Has its own -- cgit v1.2.3