05e514b1d4
It is pretty rare for aio_notify to actually set the EventNotifier. It can happen with worker threads such as thread-pool.c's, but otherwise it should never be set thanks to the ctx->notify_me optimization. The previous patch, unfortunately, added an unconditional call to event_notifier_test_and_clear; now add a userspace fast path that avoids the call. Note that it is not possible to do the same with event_notifier_set; it would break, as proved (again) by the included formal model. This patch survived over 3000 reboots on aarch64 KVM. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Tested-by: Richard W.M. Jones <rjones@redhat.com> Message-id: 1437487673-23740-7-git-send-email-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> |
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| .. | ||
| qmp | ||
| specs | ||
| aio_notify_accept.promela | ||
| aio_notify_bug.promela | ||
| aio_notify.promela | ||
| atomics.txt | ||
| bitmaps.md | ||
| blkdebug.txt | ||
| blkverify.txt | ||
| bootindex.txt | ||
| ccid.txt | ||
| ich9-ehci-uhci.cfg | ||
| image-fuzzer.txt | ||
| libcacard.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 | ||
| qdev-device-use.txt | ||
| qemupciserial.inf | ||
| rcu.txt | ||
| rdma.txt | ||
| spice-port-fqdn.txt | ||
| tracing.txt | ||
| usb2.txt | ||
| usb-storage.txt | ||
| virtio-balloon-stats.txt | ||
| vnc-ledstate-Pseudo-encoding.txt | ||
| writing-qmp-commands.txt | ||
| xbzrle.txt | ||
| xen-save-devices-state.txt | ||