[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [libvirt] [PATCH 1/2] qemu: Relax locking in DomainHasManagedSaveImage and DomainMonitorCommand



On 12/13/12 12:40, Michal Privoznik wrote:
There is no need to hold qemu lock during the whole execution
of these two APIs.
---
  src/qemu/qemu_driver.c |   12 ++++++------
  1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 2fda44e..74e442b 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -3288,6 +3288,7 @@ qemuDomainHasManagedSaveImage(virDomainPtr dom, unsigned int flags)

      qemuDriverLock(driver);
      vm = virDomainFindByUUID(&driver->domains, dom->uuid);
+    qemuDriverUnlock(driver);
      if (!vm) {
          char uuidstr[VIR_UUID_STRING_BUFLEN];
          virUUIDFormat(dom->uuid, uuidstr);
@@ -3301,7 +3302,6 @@ qemuDomainHasManagedSaveImage(virDomainPtr dom, unsigned int flags)
  cleanup:
      if (vm)
          virDomainObjUnlock(vm);
-    qemuDriverUnlock(driver);
      return ret;
  }

This is already taken care of upstream with:
commit 2745177b346a0ebbd3629e298178c60a54af242a
Author: Peter Krempa <pkrempa redhat com>
Date:   Tue Dec 11 19:28:17 2012 +0100

    qemu: Refactor managed save functions to use domain lookup helpers



@@ -12676,6 +12676,7 @@ static int qemuDomainMonitorCommand(virDomainPtr domain, const char *cmd,

      qemuDriverLock(driver);
      vm = virDomainFindByUUID(&driver->domains, domain->uuid);
+    qemuDriverUnlock(driver);
      if (!vm) {
          char uuidstr[VIR_UUID_STRING_BUFLEN];
          virUUIDFormat(domain->uuid, uuidstr);
@@ -12688,9 +12689,9 @@ static int qemuDomainMonitorCommand(virDomainPtr domain, const char *cmd,
          virReportError(VIR_ERR_OPERATION_INVALID,
                         "%s", _("domain is not running"));
          goto cleanup;
-   }
+    }

-    if (qemuDomainObjBeginJobWithDriver(driver, vm, QEMU_JOB_MODIFY) < 0)
+    if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
          goto cleanup;

      if (!virDomainObjIsActive(vm)) {
@@ -12705,9 +12706,9 @@ static int qemuDomainMonitorCommand(virDomainPtr domain, const char *cmd,

      hmp = !!(flags & VIR_DOMAIN_QEMU_MONITOR_COMMAND_HMP);

-    qemuDomainObjEnterMonitorWithDriver(driver, vm);
+    qemuDomainObjEnterMonitor(driver, vm);
      ret = qemuMonitorArbitraryCommand(priv->mon, cmd, result, hmp);
-    qemuDomainObjExitMonitorWithDriver(driver, vm);
+    qemuDomainObjExitMonitor(driver, vm);

  endjob:
      if (qemuDomainObjEndJob(driver, vm) == 0) {
@@ -12717,7 +12718,6 @@ endjob:
  cleanup:
      if (vm)
          virDomainObjUnlock(vm);
-    qemuDriverUnlock(driver);
      return ret;
  }

This cleanup makes sense, but it'd be great to take advantage of the lookup helpers I introduced lately to decrease the complexity even more.




Peter


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]