From 606a93eac7434332c39c54015d1e774293e9605d Mon Sep 17 00:00:00 2001
Message-Id: <606a93eac7434332c39c54015d1e774293e9605d@dist-git>
From: Martin Kletzander <mkletzan@redhat.com>
Date: Mon, 5 Feb 2018 13:39:20 +0100
Subject: [PATCH] qemu: Refresh capabilities when creating resctrl allocation

Since one of the things in capabilities (info from resctrl updated with data
about caches) can be change on the system by remounting the /sys/fs/resctrl with
different options, the capabilities need to be refreshed.  There is a better fix
in the works, but it's going to be way bigger than this (hence the XXX note
there), so for the time being let's workaround this.  And in order not to slow
down the domain starting, only get the capabilities if there are any cachetunes.

Relates-to: https://bugzilla.redhat.com/show_bug.cgi?id=1540780

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
(cherry picked from commit 3cac2a6c93c424d55b865a05635d96e0b1aa9d36)
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
---
 src/qemu/qemu_process.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 3853112924..c86f7d3c5b 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -2511,9 +2511,15 @@ qemuProcessResctrlCreate(virQEMUDriverPtr driver,
 {
     int ret = -1;
     size_t i = 0;
-    virCapsPtr caps = virQEMUDriverGetCapabilities(driver, false);
+    virCapsPtr caps = NULL;
     qemuDomainObjPrivatePtr priv = vm->privateData;
 
+    if (!vm->def->ncachetunes)
+        return 0;
+
+    /* Force capability refresh since resctrl info can change
+     * XXX: move cache info into virresctrl so caps are not needed */
+    caps = virQEMUDriverGetCapabilities(driver, true);
     if (!caps)
         return -1;
 
-- 
2.16.1