Re: [libvirt] [PATCH] Drop dependency on pm-is-supported
On 03/28/2014 10:32 AM, Cédric Bosdonnat wrote:
From: Cédric Bosdonnat <cedric.bosdonnat(a)free.fr>
pm-is-supported is the only thing needed in pm-utils, better get rid of
it since systemd is heavily used for libvirt.
---
src/util/virnodesuspend.c | 34 ++++++++++++++++++++--------------
1 file changed, 20 insertions(+), 14 deletions(-)
You also need to modify libvirt.spec.in to drop the dependency.
+ if (virFileReadAll("/sys/power/state", 1024, &buf) < 0)
+ goto cleanup;
+
+ states = virStringSplit(buf, " ", 0);
+
+ canSuspend = (virStringArrayHasString(states, "mem") ||
+ virStringArrayHasString(states, "standby"));
+ canHibernate = virStringArrayHasString(states, "disk");
pm-is-supported checks a bit more than what your replacement checks.
For suspend, it declares yes if any of these succeed:
grep -q mem /sys/power/state
[ -c /dev/pmu ] && pm-pmu --check
grep -q standby /sys/power/state
For hibernate, it requires that BOTH of these succeed:
[ -f /sys/power/disk ]
grep -q disk /sys/power/state
For hybrid, it requires that all three succeed:
[ -f /sys/power/disk ] && \
grep -q disk /sys/power/state && \
grep -q suspend /sys/power/disk
as well as having fallback code to fake a hybrid sleep by joining the
other two states.
+
switch (target) {
case VIR_NODE_SUSPEND_TARGET_MEM:
- cmd = virCommandNewArgList("pm-is-supported", "--suspend",
NULL);
+ *supported = canSuspend;
break;
case VIR_NODE_SUSPEND_TARGET_DISK:
- cmd = virCommandNewArgList("pm-is-supported", "--hibernate",
NULL);
+ *supported = canHibernate;
break;
case VIR_NODE_SUSPEND_TARGET_HYBRID:
- cmd = virCommandNewArgList("pm-is-supported",
"--suspend-hybrid", NULL);
+ *supported = canSuspend && canHibernate;
I'm not sure if your simpler checks will cause us to declare an action
unsupported on systems where it was previously declared supported by
pm-is-supported. I think the idea makes sense, but I'd like a second
opinion that we aren't hurting ourselves by doing fewer checks than what
we are replacing.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
Attachments:
- signature.asc (application/pgp-signature — 604 bytes)