7c9b2bf677
QemuEvents are used heavily by call_rcu. We do not want them to be slow, but the current implementation does a kernel call on every invocation of qemu_event_* and won't cut it. So, wrap a Win32 manual-reset event with a fast userspace path. The states and transitions are the same as for the futex and mutex/condvar implementations, but the slow path is different of course. The idea is to reset the Win32 event lazily, as part of a test-reset-test-wait sequence. Such a sequence is, indeed, how QemuEvents are used by RCU and other subsystems! The patch includes a formal model of the algorithm. Tested-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Weil <sw@weilnetz.de> |
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| .. | ||
| qmp | ||
| specs | ||
| aio_notify.promela | ||
| aio_notify_accept.promela | ||
| aio_notify_bug.promela | ||
| atomics.txt | ||
| bitmaps.md | ||
| blkdebug.txt | ||
| blkverify.txt | ||
| bootindex.txt | ||
| ccid.txt | ||
| ich9-ehci-uhci.cfg | ||
| image-fuzzer.txt | ||
| live-block-ops.txt | ||
| memory-hotplug.txt | ||
| memory.txt | ||
| migration.txt | ||
| multi-thread-compression.txt | ||
| multiple-iothreads.txt | ||
| multiseat.txt | ||
| pci_expander_bridge.txt | ||
| q35-chipset.cfg | ||
| qapi-code-gen.txt | ||
| qcow2-cache.txt | ||
| qdev-device-use.txt | ||
| qemupciserial.inf | ||
| rcu.txt | ||
| rdma.txt | ||
| spice-port-fqdn.txt | ||
| tracing.txt | ||
| usb-storage.txt | ||
| usb2.txt | ||
| virtio-balloon-stats.txt | ||
| vnc-ledstate-Pseudo-encoding.txt | ||
| win32-qemu-event.promela | ||
| writing-qmp-commands.txt | ||
| xbzrle.txt | ||
| xen-save-devices-state.txt | ||