[libvirt] [PATCH 2/7] qemu: Abstract code for memory controller setting into a helper

[Osier Yang]

On 20/05/13 19:08, Daniel P. Berrange wrote:
> On Fri, May 17, 2013 at 07:59:32PM +0800, Osier Yang wrote:
>> ---
>>   src/qemu/qemu_cgroup.c | 120 ++++++++++++++++++++++++++++---------------------
>>   1 file changed, 68 insertions(+), 52 deletions(-)
>>
>> diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c
>> index 0c4792e..2751be0 100644
>> --- a/src/qemu/qemu_cgroup.c
>> +++ b/src/qemu/qemu_cgroup.c
>> @@ -455,6 +455,72 @@ qemuSetupBlkioCgroup(virDomainObjPtr vm)
>>       return 0;
>>   }
>>   
> My email client is showing trailing whitespace here. Not sure
> if that is genuine or not. Also 2 blank lines between functions

I found no trailing spaces.

>
>> +static int
>> +qemuSetupMemoryCgroup(virDomainObjPtr vm) {
> Put the '{' on a new line as you did with previous patches

Okay.

>
>> +    qemuDomainObjPrivatePtr priv = vm->privateData;
>> +    unsigned long long hard_limit;
>> +    int rc;
>> +    int i;
>> +
>> +    if (!virCgroupHasController(priv->cgroup,VIR_CGROUP_CONTROLLER_MEMORY)) {
>> +        if (vm->def->mem.hard_limit != 0 ||
>> +            vm->def->mem.soft_limit != 0 ||
>> +            vm->def->mem.swap_hard_limit != 0) {
>> +            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
>> +                           _("Memory cgroup is not available on this host"));
>> +            return -1;
>> +        } else {
>> +            VIR_WARN("Could not autoset a RSS limit for domain %s", vm->def->name);
>> +            return 0;
>> +        }
> Not sure why we need this VIR_WARN at all. If no limits are set in the XML,
> then we should not warn about a missing feature that we don't actually
> need.

Agreed. Having a warning for no XML config is confused. I removed it.
>
>
>> @@ -668,58 +734,8 @@ int qemuSetupCgroup(virQEMUDriverPtr driver,
>>       if (qemuSetupBlkioCgroup(vm) < 0)
>>           goto cleanup;
>>   
>> -    if (virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_MEMORY)) {
>> -        unsigned long long hard_limit = vm->def->mem.hard_limit;
>> -
>> -        if (!hard_limit) {
>> -            /* If there is no hard_limit set, set a reasonable one to avoid
>> -             * system thrashing caused by exploited qemu.  A 'reasonable
>> -             * limit' has been chosen:
>> -             *     (1 + k) * (domain memory + total video memory) + (32MB for
>> -             *     cache per each disk) + F
>> -             * where k = 0.5 and F = 200MB.  The cache for disks is important as
>> -             * kernel cache on the host side counts into the RSS limit. */
>> -            hard_limit = vm->def->mem.max_balloon;
>> -            for (i = 0; i < vm->def->nvideos; i++)
>> -                hard_limit += vm->def->videos[i]->vram;
>> -            hard_limit = hard_limit * 1.5 + 204800;
>> -            hard_limit += vm->def->ndisks * 32768;
>> -        }
>> -
>> -        rc = virCgroupSetMemoryHardLimit(priv->cgroup, hard_limit);
>> -        if (rc != 0) {
>> -            virReportSystemError(-rc,
>> -                                 _("Unable to set memory hard limit for domain %s"),
>> -                                 vm->def->name);
>> -            goto cleanup;
>> -        }
>> -        if (vm->def->mem.soft_limit != 0) {
>> -            rc = virCgroupSetMemorySoftLimit(priv->cgroup, vm->def->mem.soft_limit);
>> -            if (rc != 0) {
>> -                virReportSystemError(-rc,
>> -                                     _("Unable to set memory soft limit for domain %s"),
>> -                                     vm->def->name);
>> -                goto cleanup;
>> -            }
>> -        }
>> -
>> -        if (vm->def->mem.swap_hard_limit != 0) {
>> -            rc = virCgroupSetMemSwapHardLimit(priv->cgroup, vm->def->mem.swap_hard_limit);
>> -            if (rc != 0) {
>> -                virReportSystemError(-rc,
>> -                                     _("Unable to set swap hard limit for domain %s"),
>> -                                     vm->def->name);
>> -                goto cleanup;
>> -            }
>> -        }
>> -    } else if (vm->def->mem.hard_limit != 0 ||
>> -               vm->def->mem.soft_limit != 0 ||
>> -               vm->def->mem.swap_hard_limit != 0) {
>> -        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
>> -                       _("Memory cgroup is not available on this host"));
>> -    } else {
>> -        VIR_WARN("Could not autoset a RSS limit for domain %s", vm->def->name);
>> -    }
>> +    if (qemuSetupMemoryCgroup(vm) < 0)
>> +        goto cleanup;
> ACK with warning removed
>
>
Pushed. Thanks.

Osier