Laine Stump 595e26c086 qemu: drop driver lock while trying to terminate qemu process ... This patch is based on an earlier patch by Eric Blake which was never committed: https://www.redhat.com/archives/libvir-list/2011-November/msg00243.html Aside from rebasing, this patch only drops the driver lock once (prior to the first time the function sleeps), then leaves it dropped until it returns (Eric's patch would drop and re-acquire the lock around each call to sleep). At the time Eric sent his patch, the response (from Dan Berrange) was that, while it wasn't a good thing to be holding the driver lock while sleeping, we really need to rethink locking wrt the driver object, switching to a finer-grained approach that locks individual items within the driver object separately to allow for greater concurrency. This is a good plan, and at the time it made sense to not apply the patch because there was no known bug related to the driver lock being held in this function. However, we now know that the length of the wait in qemuProcessKill is sometimes too short to allow the qemu process to fully flush its disk cache before SIGKILL is sent, so we need to lengthen the timeout (in order to improve the situation with management applications until they can be updated to use the new VIR_DOMAIN_DESTROY_GRACEFUL flag added in commit 72f8a7f197). But, if we lengthen the timeout, we also lengthen the amount of time that all other threads in libvirtd are essentially blocked from doing anything (since just about everything needs to acquire the driver lock, if only for long enough to get a pointer to a domain). The solution is to modify qemuProcessKill to drop the driver lock while sleeping, as proposed in Eric's patch. Then we can increase the timeout with a clear conscience, and thus at least lower the chances that someone running with existing management software will suffer the consequence's of qemu's disk cache not being flushed. In the meantime, we still should work on Dan's proposal to make locking within the driver object more fine grained. (NB: although I couldn't find any instance where qemuProcessKill() was called with no jobs active for the domain (or some other guarantee that the current thread had at least one refcount on the domain object), this patch still follows Eric's method of temporarily adding a ref prior to unlocking the domain object, because I couldn't convince myself 100% that this was the case.)		2012-02-15 13:57:10 -05:00
..
libvirtd_qemu.aug	Add two new security label types	2012-02-02 17:44:37 -07:00
MIGRATION.txt	qemu: Implement migration job phases	2011-07-27 08:45:09 -06:00
qemu_agent.c	qemu: Implement DomainPMSuspendForDuration	2012-02-15 11:45:45 +01:00
qemu_agent.h	qemu: Implement DomainPMSuspendForDuration	2012-02-15 11:45:45 +01:00
qemu_bridge_filter.c	Remove conn parameter from virReportSystemError	2010-02-09 01:04:54 +01:00
qemu_bridge_filter.h	build: consistently indent preprocessor directives	2010-03-09 19:22:28 +01:00
qemu_capabilities.c	qemu: Set capabilities based on supported monitor commands	2012-02-15 11:37:39 +01:00
qemu_capabilities.h	qemu: Set capabilities based on supported monitor commands	2012-02-15 11:37:39 +01:00
qemu_cgroup.c	qemu: eliminate "Ignoring open failure" when using root-squash NFS	2012-02-03 16:47:43 -05:00
qemu_cgroup.h	qemu: Implement period and quota tunable XML configuration and parsing	2011-07-21 17:11:12 +08:00
qemu_command.c	Revert "qemu: add ibmvscsi controller model"	2012-02-13 21:37:03 +08:00
qemu_command.h	tests: Teach qemuxml2argvtest about spapr-vio addresses	2012-01-13 16:08:22 -07:00
qemu_conf.c	Add two new security label types	2012-02-02 17:44:37 -07:00
qemu_conf.h	Add two new security label types	2012-02-02 17:44:37 -07:00
qemu_domain.c	qemu: fix my typo at commit 74e034964c	2012-01-31 20:21:06 -07:00
qemu_domain.h	QEMU guest agent support	2012-01-24 12:19:51 +01:00
qemu_driver.c	qemu: drop driver lock while trying to terminate qemu process	2012-02-15 13:57:10 -05:00
qemu_driver.h	Split all QEMU process mangement code into separate file	2011-02-17 12:48:55 +00:00
qemu_hostdev.c	qemu: Introduce inactive PCI device list	2012-01-17 17:05:32 -07:00
qemu_hostdev.h	qemu: Keep list of USB devices attached to domains	2011-12-24 18:12:04 +01:00
qemu_hotplug.c	qemu: Refactor qemuMonitorGetBlockInfo	2012-01-27 13:07:56 +01:00
qemu_hotplug.h	qemu: Don't drop hostdev config until security label restore	2011-12-16 11:53:03 +01:00
qemu_migration.c	qemu: Fix seamless spice migration	2012-02-06 09:41:52 +01:00
qemu_migration.h	Clarify semantics of virDomainMigrate2	2011-10-14 22:04:31 +02:00
qemu_monitor_json.c	qemu: Set capabilities based on supported monitor commands	2012-02-15 11:37:39 +01:00
qemu_monitor_json.h	qemu: Set capabilities based on supported monitor commands	2012-02-15 11:37:39 +01:00
qemu_monitor_text.c	qemu: Implement virDomainGetDiskErrors	2012-02-01 10:54:15 +01:00
qemu_monitor_text.h	qemu: Refactor qemuMonitorGetBlockInfo	2012-01-27 13:07:56 +01:00
qemu_monitor.c	qemu: Set capabilities based on supported monitor commands	2012-02-15 11:37:39 +01:00
qemu_monitor.h	qemu: Set capabilities based on supported monitor commands	2012-02-15 11:37:39 +01:00
qemu_process.c	qemu: drop driver lock while trying to terminate qemu process	2012-02-15 13:57:10 -05:00
qemu_process.h	qemu: drop driver lock while trying to terminate qemu process	2012-02-15 13:57:10 -05:00
qemu.conf	Add two new security label types	2012-02-02 17:44:37 -07:00
test_libvirtd_qemu.aug	qemu: Support for overriding NOFILE limit	2011-12-22 17:49:04 +01:00
THREADS.txt	qemu: fix crash when mixing sync and async monitor jobs	2011-08-01 09:41:57 -06:00