[libvirt] [PATCH] qemu: Take all PHBs into account while calculating memlock limits

Shivaprasad G Bhat posted 1 patch 116 weeks ago
Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/libvirt tags/patchew/20170630082549.35442.44585.stgit@lep8c.aus.stglabs.ibm.com
src/qemu/qemu_domain.c  |   12 ++++++++----
tests/qemumemlocktest.c |    2 +-
2 files changed, 9 insertions(+), 5 deletions(-)

[libvirt] [PATCH] qemu: Take all PHBs into account while calculating memlock limits

Posted by Shivaprasad G Bhat 116 weeks ago
Now that the multi-phb support series is in, work on the TODO at
qemuDomainGetMemLockLimitBytes() to arrive at the correct memlock limit
value.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
---
This patch should be applied on top of Andrea's multi-phb support
patchset.

 src/qemu/qemu_domain.c  |   12 ++++++++----
 tests/qemumemlocktest.c |    2 +-
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index a3ce10a..a8293b4 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -6674,12 +6674,16 @@ qemuDomainGetMemLockLimitBytes(virDomainDefPtr def)
         unsigned long long memory;
         unsigned long long baseLimit;
         unsigned long long passthroughLimit;
-        size_t nPCIHostBridges;
+        size_t nPCIHostBridges = 0;
         bool usesVFIO = false;
 
-        /* TODO: Detect at runtime once we start using more than just
-         *       the default PCI Host Bridge */
-        nPCIHostBridges = 1;
+        for (i = 0; i < def->ncontrollers; i++) {
+            if (def->controllers[i]->type != VIR_DOMAIN_CONTROLLER_TYPE_PCI ||
+                def->controllers[i]->model != VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT) {
+                continue;
+            }
+            nPCIHostBridges++;
+        }
 
         for (i = 0; i < def->nhostdevs; i++) {
             virDomainHostdevDefPtr dev = def->hostdevs[i];
diff --git a/tests/qemumemlocktest.c b/tests/qemumemlocktest.c
index c0f1dc3..268563d 100644
--- a/tests/qemumemlocktest.c
+++ b/tests/qemumemlocktest.c
@@ -131,7 +131,7 @@ mymain(void)
 
     DO_TEST("pseries-hardlimit", 2147483648);
     DO_TEST("pseries-locked", VIR_DOMAIN_MEMORY_PARAM_UNLIMITED);
-    DO_TEST("pseries-hostdev", 2168455168);
+    DO_TEST("pseries-hostdev", 4320133120);
 
     DO_TEST("pseries-hardlimit+locked", 2147483648);
     DO_TEST("pseries-hardlimit+hostdev", 2147483648);

--
libvir-list mailing list
libvir-list@redhat.com
https://www.redhat.com/mailman/listinfo/libvir-list

Re: [libvirt] [PATCH] qemu: Take all PHBs into account while calculating memlock limits

Posted by Andrea Bolognani 115 weeks ago
On Fri, 2017-06-30 at 13:56 +0530, Shivaprasad G Bhat wrote:
> -        /* TODO: Detect at runtime once we start using more than just
> -         *       the default PCI Host Bridge */
> -        nPCIHostBridges = 1;
> +        for (i = 0; i < def->ncontrollers; i++) {
> +            if (def->controllers[i]->type != VIR_DOMAIN_CONTROLLER_TYPE_PCI ||
> +                def->controllers[i]->model != VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT) {
> +                continue;
> +            }
> +            nPCIHostBridges++;
> +        }

Just to be on the safe side, we should probably make sure the
pci-root controller is actually a PHB by looking at modelName
as well, like:

  for (i = 0; i < def->ncontrollers; i++) {
      virDomainControllerDefPtr cont = def->controllers[i];

      if (cont->type != VIR_DOMAIN_CONTROLLER_TYPE_PCI ||
          cont->model != VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT ||
          cont->opts.pciopts->modelName != VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_SPAPR_PCI_HOST_BRIDGE) {
          continue;
      }

      nPCIHostBridges++;
  }

Boy, that model name sure is a mouthful[1].

I think we might have enough occurrences of this pattern to
warrant the creation of a virDomainControllerIsPCIHostBridge()
helper function, which you could then use in your patch.

That said, it might be smarter to do so in a follow-up cleanup
commit in order not to invalidate existing Reviewed-by tags.
Laine, what would be your preference?


[1] Except for fingers. Fingerful?
-- 
Andrea Bolognani / Red Hat / Virtualization

--
libvir-list mailing list
libvir-list@redhat.com
https://www.redhat.com/mailman/listinfo/libvir-list

Re: [libvirt] [PATCH] qemu: Take all PHBs into account while calculating memlock limits

Posted by Laine Stump 115 weeks ago
On 07/03/2017 09:51 AM, Andrea Bolognani wrote:
> On Fri, 2017-06-30 at 13:56 +0530, Shivaprasad G Bhat wrote:
>> -        /* TODO: Detect at runtime once we start using more than just
>> -         *       the default PCI Host Bridge */
>> -        nPCIHostBridges = 1;
>> +        for (i = 0; i < def->ncontrollers; i++) {
>> +            if (def->controllers[i]->type != VIR_DOMAIN_CONTROLLER_TYPE_PCI ||
>> +                def->controllers[i]->model != VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT) {
>> +                continue;
>> +            }
>> +            nPCIHostBridges++;
>> +        }
> 
> Just to be on the safe side, we should probably make sure the
> pci-root controller is actually a PHB by looking at modelName
> as well, like:
> 
>   for (i = 0; i < def->ncontrollers; i++) {
>       virDomainControllerDefPtr cont = def->controllers[i];
> 
>       if (cont->type != VIR_DOMAIN_CONTROLLER_TYPE_PCI ||
>           cont->model != VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT ||
>           cont->opts.pciopts->modelName != VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_SPAPR_PCI_HOST_BRIDGE) {
>           continue;
>       }
> 
>       nPCIHostBridges++;
>   }
> 
> Boy, that model name sure is a mouthful[1].
> 
> I think we might have enough occurrences of this pattern to
> warrant the creation of a virDomainControllerIsPCIHostBridge()
> helper function, which you could then use in your patch.
> 
> That said, it might be smarter to do so in a follow-up cleanup
> commit in order not to invalidate existing Reviewed-by tags.
> Laine, what would be your preference?

Either is fine with me.

--
libvir-list mailing list
libvir-list@redhat.com
https://www.redhat.com/mailman/listinfo/libvir-list