aboutsummaryrefslogtreecommitdiff
path: root/balloon.c
AgeCommit message (Collapse)Author
2015-11-10Inhibit ballooning during postcopyDr. David Alan Gilbert
Postcopy detects accesses to pages that haven't been transferred yet using userfaultfd, and it causes exceptions on pages that are 'not present'. Ballooning also causes pages to be marked as 'not present' when the guest inflates the balloon. Potentially a balloon could be inflated to discard pages that are currently inflight during postcopy and that may be arriving at about the same time. To avoid this confusion, disable ballooning during postcopy. When disabled we drop balloon requests from the guest. Since ballooning is generally initiated by the host, the management system should avoid initiating any balloon instructions to the guest during migration, although it's not possible to know how long it would take a guest to process a request made prior to the start of migration. Guest initiated ballooning will not know if it's really freed a page of host memory or not. Queueing the requests until after migration would be nice, but is non-trivial, since the set of inflate/deflate requests have to be compared with the state of the page to know what the final outcome is allowed to be. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-22Include monitor/monitor.h exactly where neededMarkus Armbruster
In particular, don't include it into headers. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22Include qapi/qmp/qerror.h exactly where neededMarkus Armbruster
In particular, don't include it into headers. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22qerror: Clean up QERR_ macros to expand into a single stringMarkus Armbruster
These macros expand into error class enumeration constant, comma, string. Unclean. Has been that way since commit 13f59ae. The error class is always ERROR_CLASS_GENERIC_ERROR since the previous commit. Clean up as follows: * Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and delete it from the QERR_ macro. No change after preprocessing. * Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into error_setg(...). Again, no change after preprocessing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-04-24balloon: improve error msg when adding second deviceLuiz Capitulino
A VM supports only one balloon device, but due to several changes in infrastructure the error message got messed up when trying to add a second device. Fix it. Before this fix Command-line: qemu-qmp: -device virtio-balloon-pci,id=balloon0: Another balloon device already registered qemu-qmp: -device virtio-balloon-pci,id=balloon0: Adding balloon handler failed qemu-qmp: -device virtio-balloon-pci,id=balloon0: Device 'virtio-balloon-pci' could not be initialized HMP: Another balloon device already registered Adding balloon handler failed Device 'virtio-balloon-pci' could not be initialized QMP: { "execute": "device_add", "arguments": { "driver": "virtio-balloon-pci", "id": "balloon0" } } { "error": { "class": "GenericError", "desc": "Adding balloon handler failed" } } After this fix Command-line: qemu-qmp: -device virtio-balloon-pci,id=balloon0: Only one balloon device is supported qemu-qmp: -device virtio-balloon-pci,id=balloon0: Device 'virtio-balloon-pci' could not be initialized HMP: (qemu) device_add virtio-balloon-pci,id=balloon0 Only one balloon device is supported Device 'virtio-balloon-pci' could not be initialized (qemu) QMP: { "execute": "device_add", "arguments": { "driver": "virtio-balloon-pci", "id": "balloon0" } } { "error": { "class": "GenericError", "desc": "Only one balloon device is supported" } } Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2015-02-23balloon: Fix typoEric Blake
Commit 422e0501 introduced a typo (unless removing an 'o' from balloon is how you deflate it?) Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-01-29balloon: Eliminate silly QERR_ macrosMarkus Armbruster
The QERR_ macros are leftovers from the days of "rich" error objects. They're used with error_set() and qerror_report(), and expand into the first *two* arguments. This trickiness has become pointless. Clean up the balloon ones. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-01-29balloon: Factor out common "is balloon active" testMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2015-01-29balloon: Inline qemu_balloon(), qemu_balloon_status()Markus Armbruster
... and simplify a bit. Permits factoring out common error checks in the next commit. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-06-23qapi event: convert BALLOON_CHANGEWenchao Xia
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-12-19softmmu: move include files to include/sysemu/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19monitor: move include files to include/monitor/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19exec: move include files to include/exec/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19qapi: move include files to include/qobject/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-06-15Add event notification for guest balloon changesDaniel P. Berrange
After setting a balloon target value, applications have to continually poll 'query-balloon' to determine whether the guest has reacted to this request. The virtio-balloon backend knows exactly when the guest has reacted though, and thus it is possible to emit a JSON event to tell the mgmt application whenever the guest balloon changes. This introduces a new 'qemu_balloon_changed()' API which is to be called by balloon driver backends, whenever they have a change in balloon value. This takes the 'actual' balloon value, as would be found in the BalloonInfo struct. The qemu_balloon_change API emits a JSON monitor event which looks like: {"timestamp": {"seconds": 1337162462, "microseconds": 814521}, "event": "BALLOON_CHANGE", "data": {"actual": 944766976}} * balloon.c, balloon.h: Introduce qemu_balloon_changed() for emitting balloon change events on the monitor * hw/virtio-balloon.c: Invoke qemu_balloon_changed() whenever the guest changes the balloon actual value * monitor.c, monitor.h: Define QEVENT_BALLOON_CHANGE Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-04-27qapi: fix qmp_balloon() conversionLuiz Capitulino
Commit d72f326431 forgot to convert a call from qerror_report() to error_set(). Fix it. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
2011-12-06qapi: Convert balloonLuiz Capitulino
Note that the command being dropped uses the deprecated MONITOR_CMD_ASYNC API, but the new command is a regular synchronous command. There shouldn't be visible differences though, as MONITOR_CMD_ASYNC is internal only. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2011-10-27qapi: Convert query-balloonLuiz Capitulino
Please, note that some of the code supporting memory statistics is still around (eg. virtio_balloon_receive_stats() and reset_stats()). Also, the qmp_query_balloon() function is synchronous and thus doesn't make any use of the (not fully working) monitor's asynchronous command support (the old non-qapi implementation did). Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2011-09-09balloon: Disassociate handlers from balloon device on unplugAmit Shah
When a balloon device gets unplugged, allow the balloon handlers to be freed. Reported-by: Shaolong Hu <shu@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-04balloon: Reject negative balloon valuesAmit Shah
Negative balloon values don't make sense, reject them and throw a qerror with QERR_INVALID_PARAMETER_VALUE. Reported-by: Mike Cao <bcao@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com>
2011-08-04balloon: Don't allow multiple balloon handler registrationsAmit Shah
Multiple balloon devices don't make sense; disallow more than one registration attempt to register handlers. Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com>
2011-08-04balloon: Fix header comment; add CopyrightAmit Shah
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2011-08-04balloon: Separate out stat and balloon handlingAmit Shah
Passing on '0' as ballooning target to indicate retrieval of stats is bad API. It also makes 'balloon 0' in the monitor cause a segfault. Have two different functions handle the different functionality instead. Detailed explanation from Markus's review: 1. do_info_balloon() is an info_async() method. It receives a callback with argument, to be called exactly once (callback frees the argument). It passes the callback via qemu_balloon_status() and indirectly through qemu_balloon_event to virtio_balloon_to_target(). virtio_balloon_to_target() executes its balloon stats half. It stores the callback in the device state. If it can't send a stats request, it resets stats and calls the callback right away. Else, it sends a stats request. The device model runs the callback when it receives the answer. Works. 2. do_balloon() is a cmd_async() method. It receives a callback with argument, to be called when the command completes. do_balloon() calls it right before it succeeds. Odd, but should work. Nevertheless, it passes the callback on via qemu_ballon() and indirectly through qemu_balloon_event to virtio_balloon_to_target(). a. If the argument is non-zero, virtio_balloon_to_target() executes its balloon half, which doesn't use the callback in any way. Odd, but works. b. If the argument is zero, virtio_balloon_to_target() executes its balloon stats half, just like in 1. It either calls the callback right away, or arranges for it to be called later. Thus, the callback runs twice: use after free and double free. Test case: start with -S -device virtio-balloon, execute "balloon 0" in human monitor. Runs the callback first from virtio_balloon_to_target(), then again from do_balloon(). Reported-by: Mike Cao <bcao@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com>
2011-08-04balloon: Simplify code flowAmit Shah
Replace: if (foo) { ... } else { return 0; } by if (!foo) { return 0; } ... Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com>
2011-08-04balloon: Add braces around if statementsAmit Shah
Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com>
2011-08-04balloon: Make functions, local vars staticAmit Shah
balloon.h had function declarations for a couple of functions that are local to balloon.c. Make them static. Drop the 'qemu_' prefix for balloon.c-local variables, and make them static. Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com>
2011-04-15Remove unused sysemu.h include directivesBlue Swirl
Remove unused sysemu.h include directives to speed up build with the following patches. Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-09-09trace: Trace entry point of balloon request handlerPrerna Saxena
Signed-off-by: Prerna Saxena <prerna@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2010-04-09move balloon handling to balloon.cPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>