August 2019 - Devel - libvirt List Archives

[libvirt] [PATCH] vircgroup: fix partition creation for cgroups v2 without systemd
by Pavel Hrdina 02 Aug '19

02 Aug '19

On hosts without systemd libvirt is responsible for creating cgroups topology. With cgroups v2 the logic changed a bit. If we need to create new directory the detection of controllers fails because the directory doesn't exists so there is no cgroup.controllers file. To fix that issue we need to have a parent cgroup where we can look into cgroup.subtree_control to get a list of enabled controllers. To fix the issue reorder the operations to get a parent group fist so we can use it to create a new partition. <https://www.redhat.com/archives/libvir-list/2019-July/msg01309.html> Reported-by: Raghav Gururajan <rvgn(a)disroot.org> Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com> --- src/util/vircgroup.c | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c index 825f62a97b..0789630b47 100644 --- a/src/util/vircgroup.c +++ b/src/util/vircgroup.c @@ -842,6 +842,7 @@ virCgroupNewPartition(const char *path, virCgroupPtr *group) { int ret = -1; + char *tmp; VIR_AUTOFREE(char *) parentPath = NULL; VIR_AUTOFREE(char *) newPath = NULL; virCgroupPtr parent = NULL; @@ -858,25 +859,27 @@ virCgroupNewPartition(const char *path, if (virCgroupSetPartitionSuffix(path, &newPath) < 0) goto cleanup; - if (virCgroupNew(-1, newPath, NULL, controllers, group) < 0) + if (STREQ(newPath, "/")) { + ret = 0; goto cleanup; - - if (STRNEQ(newPath, "/")) { - char *tmp; - if (VIR_STRDUP(parentPath, newPath) < 0) - goto cleanup; - - tmp = strrchr(parentPath, '/'); - tmp++; - *tmp = '\0'; - - if (virCgroupNew(-1, parentPath, NULL, controllers, &parent) < 0) - goto cleanup; - - if (virCgroupMakeGroup(parent, *group, create, VIR_CGROUP_NONE) < 0) - goto cleanup; } + if (VIR_STRDUP(parentPath, newPath) < 0) + goto cleanup; + + tmp = strrchr(parentPath, '/'); + tmp++; + *tmp = '\0'; + + if (virCgroupNew(-1, parentPath, NULL, controllers, &parent) < 0) + goto cleanup; + + if (virCgroupNew(-1, newPath, parent, controllers, group) < 0) + goto cleanup; + + if (virCgroupMakeGroup(parent, *group, create, VIR_CGROUP_NONE) < 0) + goto cleanup; + ret = 0; cleanup: if (ret != 0) -- 2.21.0

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[libvirt] virtio pmem support in libvirt
by Pankaj Gupta 01 Aug '19

01 Aug '19

Hi all, Virtio-pmem support has been added to kernel[1] and qemu[2] upstream. User document[3] has more details on how to use this new device. We now need support in libvirt. Required support would be a subset of features already implemented for emulated nvdimm. We will use new virtio-pmem-pci device and don't require advance ACPI configurations. Can libvirt upstream community implement libvirt support for virtio pmem to complete the entire stack. Thank you in advance. Best regards, Pankaj [1] http://lkml.iu.edu/hypermail/linux/kernel/1907.2/02509.html [2] https://lists.sr.ht/~philmd/qemu/%3C20190702150606.24851-1-mst%40redhat.com… [3] https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg06535.html

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[libvirt] [PATCH] news: add entry for new max_threads_per_process option in qemu.conf
by Jim Fehlig 01 Aug '19

01 Aug '19

Signed-off-by: Jim Fehlig <jfehlig(a)suse.com> --- docs/news.xml | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/docs/news.xml b/docs/news.xml index 82a4ec9c84..3a20f95a0d 100644 --- a/docs/news.xml +++ b/docs/news.xml @@ -74,6 +74,17 @@ which portions of a disk have changed since a point in time. </description> </change> + <change> + <summary> + qemu: Add support for overriding max threads per process limit + </summary> + <description> + systemd-based systems impose a limit on the number of threads a + process can spawn, which in some cases can be exceeded by qemu + processes running VMs. Add a <code>max_threads_per_process</code> + option to qemu.conf to override the system default. + </description> + </change> </section> <section title="Removed features"> <change> -- 2.22.0

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