[libvirt] [PATCH v2] nwfilter: extend nwfilter reload support

[Daniel P. Berrange]

On Thu, Aug 12, 2010 at 02:18:26PM -0400, Stefan Berger wrote:
> Index: libvirt-acl/src/nwfilter/nwfilter_driver.c
> ===================================================================
> --- libvirt-acl.orig/src/nwfilter/nwfilter_driver.c
> +++ libvirt-acl/src/nwfilter/nwfilter_driver.c
> @@ -143,15 +143,25 @@ conf_init_err:
>   */
>  static int
>  nwfilterDriverReload(void) {
> +    virConnectPtr conn;
>      if (!driverState) {
>          return -1;
>      }
> 
> -    nwfilterDriverLock(driverState);
> -    virNWFilterPoolLoadAllConfigs(NULL,
> - &driverState->pools,
> -                                  driverState->configDir);
> -    nwfilterDriverUnlock(driverState);
> +    conn = virConnectOpen("qemu:///system");
> +
> +    if (conn) {
> +        /* shut down all threads -- qemud for example will restart them */
> +        virNWFilterLearnThreadsTerminate();
> +
> +        nwfilterDriverLock(driverState);
> +        virNWFilterPoolLoadAllConfigs(conn,
> + &driverState->pools,
> +                                      driverState->configDir);
> +        nwfilterDriverUnlock(driverState);
> +
> +        virConnectClose(conn);
> +    }
> 
>      return 0;

There's a small indentation issue here


>  }
> Index: libvirt-acl/src/nwfilter/nwfilter_learnipaddr.c
> ===================================================================
> --- libvirt-acl.orig/src/nwfilter/nwfilter_learnipaddr.c
> +++ libvirt-acl/src/nwfilter/nwfilter_learnipaddr.c
> @@ -855,6 +855,16 @@ virNWFilterLearnInit(void) {
>  }
> 
> 
> +void
> +virNWFilterLearnThreadsTerminate() {
> +    threadsTerminate = true;
> +
> +    while (virHashSize(pendingLearnReq) != 0)
> +        usleep((PKT_TIMEOUT_MS * 1000) / 3);
> +
> +    threadsTerminate = false;
> +}

Is there any risk of thread's failing to terminate, requiring
us to kill them, or ignore them instead of blocking forever ?

Daniel
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