1. 23 2月, 2017 1 次提交
  2. 31 1月, 2017 7 次提交
  3. 23 12月, 2016 1 次提交
  4. 09 12月, 2016 1 次提交
  5. 22 11月, 2016 1 次提交
  6. 15 11月, 2016 1 次提交
  7. 12 10月, 2016 1 次提交
  8. 26 9月, 2016 3 次提交
  9. 26 8月, 2016 3 次提交
  10. 24 8月, 2016 8 次提交
  11. 19 8月, 2016 4 次提交
  12. 07 8月, 2016 2 次提交
  13. 21 7月, 2016 3 次提交
    • N
      vz: handle gracefully races on undefining domain · b999ce97
      Nikolay Shirokovskiy 提交于
      Undefine procedure drops domain lock while waiting for detaching
      disks vz sdk call. Meanwhile vz sdk event domain-config-changed
      arrives, its handler finds domain and is blocked waiting for job
      condition. After undefine API call finishes event processing procedes
      and tries to refreshes domain config thru existing vz sdk domain handle.
      Domain does not exists anymore and event processing fails. Everything
      is fine we just don't want to see error message in log for this
      particular case.
      
      Fortunately domain has flag that domain is removed from list. This
      also imply that vz sdk domain is also undefined. Thus if we check
      for this flag right after domain is locked again on accuiring
      job condition we gracefully handle this situation.
      
      Actually the race can happen in other situations too. Any
      time we wait for job condition in mutualy exclusive job in
      time when we acquire it vz sdk domain can cease to exist.
      So instead of general internal error we can return domain
      not found which is easier to handle. We don't need to patch
      other places in mutually exclusive jobs where domain lock
      is dropped as if job is started domain can't be undefine
      by mutually exclusive undefine job.
      
      The code of this patch is quite similar to qemu driver checks
      for is domain is active after acquiring a job. The difference
      only while qemu domain is operational while process is active
      vz domain is operational while domain exists.
      b999ce97
    • N
      vz: make vz driver more responsive · 84299235
      Nikolay Shirokovskiy 提交于
      Current vz driver implementation is not usable when it comes to
      long runnig operations. Migration or saving a domain blocks all
      other operations even query ones which are expecteted to be available.
      This patch addresses this problem.
      
      All vz driver API calls fall into next 3 groups:
      1. only query domain cache (virDomainObj, vz cache statistic)
         examples are vzDomainGetState, vzDomainGetXMLDesc etc.
      2. use thread shared sdkdom object
         examples are vzDomainSetMemoryFlags, vzDomainAttachDevice etc.
      3. use no thread shared sdkdom object nor domain cache
         examples are vzDomainSnapshotListNames, vzDomainSnapshotGetXMLDesc etc
      
      API calls from group 1 don't need to be changed as they hold domain lock only
      for short period of time. These calls [1] are easily distinguished. They query
      domain object thru libvirt common code or query vz sdk statistics handle thru
      vz sdk sync operations.
      
      vzDomainInterfaceStats is the only exception. It uses sdkdom object to
      convert interface name to its vz sdk stack index which could not be saved in
      domain cache. Interface statistics is available thru this stack index as a key
      rather than name. As a result we can have accidental 'not known interface'
      errors on quering intrerface stats. The reason is that in the process of
      updating domain configuration we drop all devices and then recreate them again
      in sdkdom object and domain lock can be dropped meanwhile (to remove networks
      for existing bridged interfaces and(or) (re)create new ones). We can fix this
      by changing the way we support bridged interfaces or by reordering operations
      and changing bridged networks beforehand. Anyway this is better than moving
      this API call into 2 group and making it an exclusive job.
      
      As to API calls from group 2, first thread shared sdkdom object needs to be
      explained. vz sdk has only one handle for a given domain, thus threads need
      exclusive access to operate on it. These calls are fixed to drop and reacquire
      domain lock on any lengthy operations - namely waiting the result of async vz
      sdk operation. As lock is dropped we need to take extra reference to domain
      object if it is not taken already as domain object can be deleted from list
      while lock is dropped. As this operations use thread shared sdkdom object, the
      simplest way to make calls from group 2 be consistent to each other is to make
      them mutually exclusive. This is done by taking/releasing job condition thru
      calling correspondent job routine. This approach makes group 1 and group
      2 calls consistent to each other too. Not all calls of group 2 change the
      domain cache but those that do update it thru prlsdkUpdateDomain which holds
      the lock thoughout the update.
      
      API calls from group [2] are easily distinguished too. They use
      beginEdit/commit to change domain configuration (vzDomainSetMemoryFlags) or/and
      update domain cache from sdkdom at the end of operation (vzDomainSuspend).
      
      There is a known issue however. Frankly speaking it was introduced by ealier
      patch '[PATCH 6/9] vz: cleanup loading domain code' from a different series.
      The patch significantly reduced amount of time when the driver lock is held when
      creating domain from API call or as a result of domain added event from vz sdk.
      The problem is these two paths race on using thread shared sdkdom as we don't
      have libvirt domain object and can not lock on it. However this don't
      invalidates the patch as we can't use the former approach of preadding domain
      into the list as we need name at least and name is not given by event. Anyway
      i'm against adding half baked object into the list. Eventually this race can be
      fixed by extra measures. As to current situation races with different
      configurations are unlikely and race when adding domain thru vz driver and
      simultaneous event from vz sdk is not dangerous as configuration is the same.
      
      The last group [3] is API calls that need only sdkdom object to make vz sdk
      call and don't change thread shared sdkdom object or domain cache in any way.
      For now these are mostly domain snapshot API calls. The changes are similar to
      those of group 2 - they add extra reference and drop/reacquire the lock on waiting
      vz async call result. One can simply take the immutable sdkdom object from the
      cache and drop the lock for the rest of operations but the chosen approach
      makes implementation of these API calls somewhat similar to those of from group
      2 and thus a bit futureproof. As calls of group 3 don't need vz driver
      domain/vz sdk cache in any way, they are consistent with respect to API calls from
      groups 1 and 3.
      
      There is another exception. Calls to make-snapshot/revert-to-snapshot/migrate
      are moved to group 2. That is they are made mutually exclusive. The reason
      is that libvirt API supports control/query only for one job per domain and
      these are jobs that are likely to be queried/aborted.
      
      Appendix.
      
      [1] API calls that only query domain cache.
      (marked [*] are included for a different reason)
      
      .domainLookupByID = vzDomainLookupByID,    /* 0.10.0 */
      .domainLookupByUUID = vzDomainLookupByUUID,        /* 0.10.0 */
      .domainLookupByName = vzDomainLookupByName,        /* 0.10.0 */
      .domainGetOSType = vzDomainGetOSType,    /* 0.10.0 */
      .domainGetInfo = vzDomainGetInfo,  /* 0.10.0 */
      .domainGetState = vzDomainGetState,        /* 0.10.0 */
      .domainGetXMLDesc = vzDomainGetXMLDesc,    /* 0.10.0 */
      .domainIsPersistent = vzDomainIsPersistent,        /* 0.10.0 */
      .domainGetAutostart = vzDomainGetAutostart,        /* 0.10.0 */
      .domainGetVcpus = vzDomainGetVcpus, /* 1.2.6 */
      .domainIsActive = vzDomainIsActive, /* 1.2.10 */
      .domainIsUpdated = vzDomainIsUpdated,     /* 1.2.21 */
      .domainGetVcpusFlags = vzDomainGetVcpusFlags, /* 1.2.21 */
      .domainGetMaxVcpus = vzDomainGetMaxVcpus, /* 1.2.21 */
      .domainHasManagedSaveImage = vzDomainHasManagedSaveImage, /* 1.2.13 */
      .domainGetMaxMemory = vzDomainGetMaxMemory, /* 1.2.15 */
      .domainBlockStats = vzDomainBlockStats, /* 1.2.17 */
      .domainBlockStatsFlags = vzDomainBlockStatsFlags, /* 1.2.17 */
      .domainInterfaceStats = vzDomainInterfaceStats, /* 1.2.17 */                   [*]
      .domainMemoryStats = vzDomainMemoryStats, /* 1.2.17 */
      .domainMigrateBegin3Params = vzDomainMigrateBegin3Params, /* 1.3.5 */
      .domainMigrateConfirm3Params = vzDomainMigrateConfirm3Params, /* 1.3.5 */
      
      [2] API calls that use thread shared sdkdom object
      (marked [*] are included for a different reason)
      
      .domainSuspend = vzDomainSuspend,    /* 0.10.0 */
      .domainResume = vzDomainResume,    /* 0.10.0 */
      .domainDestroy = vzDomainDestroy,  /* 0.10.0 */
      .domainShutdown = vzDomainShutdown, /* 0.10.0 */
      .domainCreate = vzDomainCreate,    /* 0.10.0 */
      .domainCreateWithFlags = vzDomainCreateWithFlags, /* 1.2.10 */
      .domainReboot = vzDomainReboot, /* 1.3.0 */
      .domainDefineXML = vzDomainDefineXML,      /* 0.10.0 */
      .domainDefineXMLFlags = vzDomainDefineXMLFlags, /* 1.2.12 */ (update part)
      .domainUndefine = vzDomainUndefine, /* 1.2.10 */
      .domainAttachDevice = vzDomainAttachDevice, /* 1.2.15 */
      .domainAttachDeviceFlags = vzDomainAttachDeviceFlags, /* 1.2.15 */
      .domainDetachDevice = vzDomainDetachDevice, /* 1.2.15 */
      .domainDetachDeviceFlags = vzDomainDetachDeviceFlags, /* 1.2.15 */
      .domainSetUserPassword = vzDomainSetUserPassword, /* 1.3.6 */
      .domainManagedSave = vzDomainManagedSave, /* 1.2.14 */
      .domainSetMemoryFlags = vzDomainSetMemoryFlags, /* 1.3.4 */
      .domainSetMemory = vzDomainSetMemory, /* 1.3.4 */
      .domainRevertToSnapshot = vzDomainRevertToSnapshot, /* 1.3.5 */                  [*]
      .domainSnapshotCreateXML = vzDomainSnapshotCreateXML, /* 1.3.5 */                [*]
      .domainMigratePerform3Params = vzDomainMigratePerform3Params, /* 1.3.5 */        [*]
      .domainUpdateDeviceFlags = vzDomainUpdateDeviceFlags, /* 2.0.0 */
      prlsdkHandleVmConfigEvent
      
      [3] API calls that do not use thread shared sdkdom object
      
      .domainManagedSaveRemove = vzDomainManagedSaveRemove, /* 1.2.14 */
      .domainSnapshotNum = vzDomainSnapshotNum, /* 1.3.5 */
      .domainSnapshotListNames = vzDomainSnapshotListNames, /* 1.3.5 */
      .domainListAllSnapshots = vzDomainListAllSnapshots, /* 1.3.5 */
      .domainSnapshotGetXMLDesc = vzDomainSnapshotGetXMLDesc, /* 1.3.5 */
      .domainSnapshotNumChildren = vzDomainSnapshotNumChildren, /* 1.3.5 */
      .domainSnapshotListChildrenNames = vzDomainSnapshotListChildrenNames, /* 1.3.5 */
      .domainSnapshotListAllChildren = vzDomainSnapshotListAllChildren, /* 1.3.5 */
      .domainSnapshotLookupByName = vzDomainSnapshotLookupByName, /* 1.3.5 */
      .domainHasCurrentSnapshot = vzDomainHasCurrentSnapshot, /* 1.3.5 */
      .domainSnapshotGetParent = vzDomainSnapshotGetParent, /* 1.3.5 */
      .domainSnapshotCurrent = vzDomainSnapshotCurrent, /* 1.3.5 */
      .domainSnapshotIsCurrent = vzDomainSnapshotIsCurrent, /* 1.3.5 */
      .domainSnapshotHasMetadata = vzDomainSnapshotHasMetadata, /* 1.3.5 */
      .domainSnapshotDelete = vzDomainSnapshotDelete, /* 1.3.5 */
      
      [4] Known issues.
      
      1. accidental errors on getting network statistics
      2. race with simultaneous use of thread shared domain object on paths
       of adding domain thru API and adding domain on vz sdk domain added event.
      84299235
    • N
      5013ad4e
  14. 19 7月, 2016 4 次提交