On Fri, 2018-10-05 at 12:14 +0200, Michal Privoznik wrote:
On 10/02/2018 10:44 AM, Pavel Hrdina wrote:
This enables to use both cgroup v1 and v2 at the same time together with libvirt. It is supported by kernel and there is valid use- case, not all controllers are implemented in cgroup v2 so there might be configurations where administrator would enable these missing controllers in cgroup v1.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com> --- src/util/vircgroup.c | 351 ++++++++++++++++++++++++++---- ------ src/util/vircgroupbackend.c | 20 ++ src/util/vircgroupbackend.h | 16 +- src/util/vircgrouppriv.h | 2 +- 4 files changed, 291 insertions(+), 98 deletions(-)
diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c index dc249bfe33..4aec5f1bcf 100644 --- a/src/util/vircgroup.c +++ b/src/util/vircgroup.c @@ -228,6 +228,7 @@ virCgroupDetectMounts(virCgroupPtr group) struct mntent entry; char buf[CGROUP_MAX_VAL]; int ret = -1; + size_t i;
mounts = fopen("/proc/mounts", "r"); if (mounts == NULL) { @@ -236,11 +237,14 @@ virCgroupDetectMounts(virCgroupPtr group) }
while (getmntent_r(mounts, &entry, buf, sizeof(buf)) != NULL) { - if (group->backend->detectMounts(group, - entry.mnt_type, - entry.mnt_opts, - entry.mnt_dir) < 0) { - goto cleanup; + for (i = 0; i < VIR_CGROUP_BACKEND_TYPE_LAST; i++) { + if (group->backends[i] && + group->backends[i]->detectMounts(group, + entry.mnt_type, + entry.mnt_opts, + entry.mnt_dir) < 0) { + goto cleanup; + } } }
@@ -303,6 +307,7 @@ virCgroupDetectPlacement(virCgroupPtr group, }
while (fgets(line, sizeof(line), mapping) != NULL) { + size_t i; char *controllers = strchr(line, ':'); char *selfpath = controllers ? strchr(controllers + 1, ':') : NULL; char *nl = selfpath ? strchr(selfpath, '\n') : NULL; @@ -317,9 +322,12 @@ virCgroupDetectPlacement(virCgroupPtr group, controllers++; selfpath++;
- if (group->backend->detectPlacement(group, path, controllers, - selfpath) < 0) { - goto cleanup; + for (i = 0; i < VIR_CGROUP_BACKEND_TYPE_LAST; i++) { + if (group->backends[i] && + group->backends[i]->detectPlacement(group, path, controllers, + selfpath) < 0) { + goto cleanup; + }
So a loop like this appears all over the patch:
for (i = 0; i < VIR_CGROUP_BACKEND_TYPE_LAST; i++) { if (group->backends[i] && group->backends[i]->cb(); }
I wonder if we should have wrappers around these chunks of code. But that could be saved as a follow up patch.
We already have a macro for something similar that could be expanded and reused in all of those. And, yes, I totally agree that it could be done as a follow-up patch.
} }
@@ -338,8 +346,9 @@ virCgroupDetect(virCgroupPtr group, const char *path, virCgroupPtr parent) { - int rc; size_t i; + bool backendAvailable = false; + int controllersAvailable = 0; virCgroupBackendPtr *backends = virCgroupBackendGetAll();
VIR_DEBUG("group=%p controllers=%d path=%s parent=%p", @@ -350,31 +359,40 @@ virCgroupDetect(virCgroupPtr group,
for (i = 0; i < VIR_CGROUP_BACKEND_TYPE_LAST; i++) { if (backends[i] && backends[i]->available()) { - group->backend = backends[i]; - break; + group->backends[i] = backends[i]; + backendAvailable = true;
No need to remove the 'break'.
} }
ACK
Michal
-- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list