File libvirt-qemu-Avoid-holding-the-driver-lock-in-trivial-snapshot-API-s.patch of Package libvirt
From e829b5678423a6a0be8d5d4c70db6eb8f60cdcf1 Mon Sep 17 00:00:00 2001
Message-Id: <e829b5678423a6a0be8d5d4c70db6eb8f60cdcf1.1350990678.git.jdenemar@redhat.com>
From: Peter Krempa <pkrempa@redhat.com>
Date: Fri, 19 Oct 2012 21:54:26 -0600
Subject: [PATCH] qemu: Avoid holding the driver lock in trivial snapshot
API's
https://bugzilla.redhat.com/show_bug.cgi?id=772088
In most of the snapshot API's there's no need to hold the driver lock
the whole time.
This patch adds helper functions that get the domain object in functions
that don't require the driver lock and simplifies call paths from
snapshot-related API's.
(cherry picked from commit 35fe4e7e2ed77b67b3b0d7470787f51e05ec7d9f)
---
src/qemu/qemu_driver.c | 267 +++++++++++++++----------------------------------
1 file changed, 81 insertions(+), 186 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 5f1a559..8a58d76 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -187,6 +187,63 @@ struct qemuAutostartData {
virConnectPtr conn;
};
+
+/* Looks up the domain object and unlocks the driver. The returned domain
+ * object is locked and the caller is responsible for unlocking it. */
+static virDomainObjPtr
+qemuDomObjFromDomain(virDomainPtr domain)
+{
+ struct qemud_driver *driver = domain->conn->privateData;
+ virDomainObjPtr vm;
+ char uuidstr[VIR_UUID_STRING_BUFLEN];
+
+ qemuDriverLock(driver);
+ vm = virDomainFindByUUID(&driver->domains, domain->uuid);
+ qemuDriverUnlock(driver);
+ if (!vm) {
+ virUUIDFormat(domain->uuid, uuidstr);
+ virReportError(VIR_ERR_NO_DOMAIN,
+ _("no domain with matching uuid '%s'"), uuidstr);
+ }
+
+ return vm;
+}
+
+
+/* Looks up the domain object from snapshot and unlocks the driver. The
+ * returned domain object is locked and the caller is responsible for
+ * unlocking it */
+static virDomainObjPtr
+qemuDomObjFromSnapshot(virDomainSnapshotPtr snapshot)
+{
+ return qemuDomObjFromDomain(snapshot->domain);
+}
+
+
+/* Looks up snapshot object from VM and name */
+static virDomainSnapshotObjPtr
+qemuSnapObjFromName(virDomainObjPtr vm,
+ const char *name)
+{
+ virDomainSnapshotObjPtr snap = NULL;
+ snap = virDomainSnapshotFindByName(vm->snapshots, name);
+ if (!snap)
+ virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
+ _("no domain snapshot with matching name '%s'"),
+ name);
+
+ return snap;
+}
+
+
+/* Looks up snapshot object from VM and snapshotPtr */
+static virDomainSnapshotObjPtr
+qemuSnapObjFromSnapshot(virDomainObjPtr vm,
+ virDomainSnapshotPtr snapshot)
+{
+ return qemuSnapObjFromName(vm, snapshot->name);
+}
+
static void
qemuAutostartDomain(void *payload, const void *name ATTRIBUTE_UNUSED,
void *opaque)
@@ -11352,22 +11409,14 @@ static int qemuDomainSnapshotListNames(virDomainPtr domain, char **names,
int nameslen,
unsigned int flags)
{
- struct qemud_driver *driver = domain->conn->privateData;
virDomainObjPtr vm = NULL;
int n = -1;
virCheckFlags(VIR_DOMAIN_SNAPSHOT_LIST_ROOTS |
VIR_DOMAIN_SNAPSHOT_FILTERS_ALL, -1);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromDomain(domain)))
goto cleanup;
- }
n = virDomainSnapshotObjListGetNames(vm->snapshots, NULL, names, nameslen,
flags);
@@ -11375,36 +11424,26 @@ static int qemuDomainSnapshotListNames(virDomainPtr domain, char **names,
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return n;
}
static int qemuDomainSnapshotNum(virDomainPtr domain,
unsigned int flags)
{
- struct qemud_driver *driver = domain->conn->privateData;
virDomainObjPtr vm = NULL;
int n = -1;
virCheckFlags(VIR_DOMAIN_SNAPSHOT_LIST_ROOTS |
VIR_DOMAIN_SNAPSHOT_FILTERS_ALL, -1);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromDomain(domain)))
goto cleanup;
- }
n = virDomainSnapshotObjListNum(vm->snapshots, NULL, flags);
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return n;
}
@@ -11412,29 +11451,20 @@ static int
qemuDomainListAllSnapshots(virDomainPtr domain, virDomainSnapshotPtr **snaps,
unsigned int flags)
{
- struct qemud_driver *driver = domain->conn->privateData;
virDomainObjPtr vm = NULL;
int n = -1;
virCheckFlags(VIR_DOMAIN_SNAPSHOT_LIST_ROOTS |
VIR_DOMAIN_SNAPSHOT_FILTERS_ALL, -1);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromDomain(domain)))
goto cleanup;
- }
n = virDomainListSnapshots(vm->snapshots, NULL, domain, snaps, flags);
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return n;
}
@@ -11444,7 +11474,6 @@ qemuDomainSnapshotListChildrenNames(virDomainSnapshotPtr snapshot,
int nameslen,
unsigned int flags)
{
- struct qemud_driver *driver = snapshot->domain->conn->privateData;
virDomainObjPtr vm = NULL;
virDomainSnapshotObjPtr snap = NULL;
int n = -1;
@@ -11452,23 +11481,11 @@ qemuDomainSnapshotListChildrenNames(virDomainSnapshotPtr snapshot,
virCheckFlags(VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS |
VIR_DOMAIN_SNAPSHOT_FILTERS_ALL, -1);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, snapshot->domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(snapshot->domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromSnapshot(snapshot)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, snapshot->name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no domain snapshot with matching name '%s'"),
- snapshot->name);
+ if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto cleanup;
- }
n = virDomainSnapshotObjListGetNames(vm->snapshots, snap, names, nameslen,
flags);
@@ -11476,7 +11493,6 @@ qemuDomainSnapshotListChildrenNames(virDomainSnapshotPtr snapshot,
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return n;
}
@@ -11484,7 +11500,6 @@ static int
qemuDomainSnapshotNumChildren(virDomainSnapshotPtr snapshot,
unsigned int flags)
{
- struct qemud_driver *driver = snapshot->domain->conn->privateData;
virDomainObjPtr vm = NULL;
virDomainSnapshotObjPtr snap = NULL;
int n = -1;
@@ -11492,30 +11507,17 @@ qemuDomainSnapshotNumChildren(virDomainSnapshotPtr snapshot,
virCheckFlags(VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS |
VIR_DOMAIN_SNAPSHOT_FILTERS_ALL, -1);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, snapshot->domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(snapshot->domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromSnapshot(snapshot)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, snapshot->name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no domain snapshot with matching name '%s'"),
- snapshot->name);
+ if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto cleanup;
- }
n = virDomainSnapshotObjListNum(vm->snapshots, snap, flags);
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return n;
}
@@ -11524,7 +11526,6 @@ qemuDomainSnapshotListAllChildren(virDomainSnapshotPtr snapshot,
virDomainSnapshotPtr **snaps,
unsigned int flags)
{
- struct qemud_driver *driver = snapshot->domain->conn->privateData;
virDomainObjPtr vm = NULL;
virDomainSnapshotObjPtr snap = NULL;
int n = -1;
@@ -11532,23 +11533,11 @@ qemuDomainSnapshotListAllChildren(virDomainSnapshotPtr snapshot,
virCheckFlags(VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS |
VIR_DOMAIN_SNAPSHOT_FILTERS_ALL, -1);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, snapshot->domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(snapshot->domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromSnapshot(snapshot)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, snapshot->name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no domain snapshot with matching name '%s'"),
- snapshot->name);
+ if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto cleanup;
- }
n = virDomainListSnapshots(vm->snapshots, snap, snapshot->domain, snaps,
flags);
@@ -11556,7 +11545,6 @@ qemuDomainSnapshotListAllChildren(virDomainSnapshotPtr snapshot,
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return n;
}
@@ -11564,64 +11552,42 @@ static virDomainSnapshotPtr qemuDomainSnapshotLookupByName(virDomainPtr domain,
const char *name,
unsigned int flags)
{
- struct qemud_driver *driver = domain->conn->privateData;
virDomainObjPtr vm;
virDomainSnapshotObjPtr snap = NULL;
virDomainSnapshotPtr snapshot = NULL;
virCheckFlags(0, NULL);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromDomain(domain)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no snapshot with matching name '%s'"), name);
+ if (!(snap = qemuSnapObjFromName(vm, name)))
goto cleanup;
- }
snapshot = virGetDomainSnapshot(domain, snap->def->name);
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return snapshot;
}
static int qemuDomainHasCurrentSnapshot(virDomainPtr domain,
unsigned int flags)
{
- struct qemud_driver *driver = domain->conn->privateData;
virDomainObjPtr vm;
int ret = -1;
virCheckFlags(0, -1);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromDomain(domain)))
goto cleanup;
- }
ret = (vm->current_snapshot != NULL);
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return ret;
}
@@ -11629,30 +11595,17 @@ static virDomainSnapshotPtr
qemuDomainSnapshotGetParent(virDomainSnapshotPtr snapshot,
unsigned int flags)
{
- struct qemud_driver *driver = snapshot->domain->conn->privateData;
virDomainObjPtr vm;
virDomainSnapshotObjPtr snap = NULL;
virDomainSnapshotPtr parent = NULL;
virCheckFlags(0, NULL);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, snapshot->domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(snapshot->domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromSnapshot(snapshot)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, snapshot->name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no domain snapshot with matching name '%s'"),
- snapshot->name);
+ if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto cleanup;
- }
if (!snap->def->parent) {
virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
@@ -11666,28 +11619,19 @@ qemuDomainSnapshotGetParent(virDomainSnapshotPtr snapshot,
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return parent;
}
static virDomainSnapshotPtr qemuDomainSnapshotCurrent(virDomainPtr domain,
unsigned int flags)
{
- struct qemud_driver *driver = domain->conn->privateData;
virDomainObjPtr vm;
virDomainSnapshotPtr snapshot = NULL;
virCheckFlags(0, NULL);
- qemuDriverLock(driver);
- vm = virDomainFindByUUID(&driver->domains, domain->uuid);
- if (!vm) {
- char uuidstr[VIR_UUID_STRING_BUFLEN];
- virUUIDFormat(domain->uuid, uuidstr);
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromDomain(domain)))
goto cleanup;
- }
if (!vm->current_snapshot) {
virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT, "%s",
@@ -11700,14 +11644,12 @@ static virDomainSnapshotPtr qemuDomainSnapshotCurrent(virDomainPtr domain,
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return snapshot;
}
static char *qemuDomainSnapshotGetXMLDesc(virDomainSnapshotPtr snapshot,
unsigned int flags)
{
- struct qemud_driver *driver = snapshot->domain->conn->privateData;
virDomainObjPtr vm = NULL;
char *xml = NULL;
virDomainSnapshotObjPtr snap = NULL;
@@ -11715,29 +11657,19 @@ static char *qemuDomainSnapshotGetXMLDesc(virDomainSnapshotPtr snapshot,
virCheckFlags(VIR_DOMAIN_XML_SECURE, NULL);
- qemuDriverLock(driver);
- virUUIDFormat(snapshot->domain->uuid, uuidstr);
- vm = virDomainFindByUUID(&driver->domains, snapshot->domain->uuid);
- if (!vm) {
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromSnapshot(snapshot)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, snapshot->name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no domain snapshot with matching name '%s'"),
- snapshot->name);
+ if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto cleanup;
- }
+
+ virUUIDFormat(snapshot->domain->uuid, uuidstr);
xml = virDomainSnapshotDefFormat(uuidstr, snap->def, flags, 0);
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return xml;
}
@@ -11745,30 +11677,17 @@ static int
qemuDomainSnapshotIsCurrent(virDomainSnapshotPtr snapshot,
unsigned int flags)
{
- struct qemud_driver *driver = snapshot->domain->conn->privateData;
virDomainObjPtr vm = NULL;
int ret = -1;
virDomainSnapshotObjPtr snap = NULL;
- char uuidstr[VIR_UUID_STRING_BUFLEN];
virCheckFlags(0, -1);
- qemuDriverLock(driver);
- virUUIDFormat(snapshot->domain->uuid, uuidstr);
- vm = virDomainFindByUUID(&driver->domains, snapshot->domain->uuid);
- if (!vm) {
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromSnapshot(snapshot)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, snapshot->name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no domain snapshot with matching name '%s'"),
- snapshot->name);
+ if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto cleanup;
- }
ret = (vm->current_snapshot &&
STREQ(snapshot->name, vm->current_snapshot->def->name));
@@ -11776,7 +11695,6 @@ qemuDomainSnapshotIsCurrent(virDomainSnapshotPtr snapshot,
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return ret;
}
@@ -11785,30 +11703,17 @@ static int
qemuDomainSnapshotHasMetadata(virDomainSnapshotPtr snapshot,
unsigned int flags)
{
- struct qemud_driver *driver = snapshot->domain->conn->privateData;
virDomainObjPtr vm = NULL;
int ret = -1;
virDomainSnapshotObjPtr snap = NULL;
- char uuidstr[VIR_UUID_STRING_BUFLEN];
virCheckFlags(0, -1);
- qemuDriverLock(driver);
- virUUIDFormat(snapshot->domain->uuid, uuidstr);
- vm = virDomainFindByUUID(&driver->domains, snapshot->domain->uuid);
- if (!vm) {
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromSnapshot(snapshot)))
goto cleanup;
- }
- snap = virDomainSnapshotFindByName(vm->snapshots, snapshot->name);
- if (!snap) {
- virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
- _("no domain snapshot with matching name '%s'"),
- snapshot->name);
+ if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto cleanup;
- }
/* XXX Someday, we should recognize internal snapshots in qcow2
* images that are not tied to a libvirt snapshot; if we ever do
@@ -11818,7 +11723,6 @@ qemuDomainSnapshotHasMetadata(virDomainSnapshotPtr snapshot,
cleanup:
if (vm)
virDomainObjUnlock(vm);
- qemuDriverUnlock(driver);
return ret;
}
@@ -12491,9 +12395,7 @@ qemuDomainOpenConsole(virDomainPtr dom,
virStreamPtr st,
unsigned int flags)
{
- struct qemud_driver *driver = dom->conn->privateData;
virDomainObjPtr vm = NULL;
- char uuidstr[VIR_UUID_STRING_BUFLEN];
int ret = -1;
int i;
virDomainChrDefPtr chr = NULL;
@@ -12502,15 +12404,8 @@ qemuDomainOpenConsole(virDomainPtr dom,
virCheckFlags(VIR_DOMAIN_CONSOLE_SAFE |
VIR_DOMAIN_CONSOLE_FORCE, -1);
- qemuDriverLock(driver);
- virUUIDFormat(dom->uuid, uuidstr);
- vm = virDomainFindByUUID(&driver->domains, dom->uuid);
- qemuDriverUnlock(driver);
- if (!vm) {
- virReportError(VIR_ERR_NO_DOMAIN,
- _("no domain with matching uuid '%s'"), uuidstr);
+ if (!(vm = qemuDomObjFromDomain(dom)))
goto cleanup;
- }
if (!virDomainObjIsActive(vm)) {
virReportError(VIR_ERR_OPERATION_INVALID,
--
1.7.12.4
