Re: [libvirt] [RFC v4] Export KVM Host Power Management capabilities
On 08/09/2011 09:29 AM, Srivatsa S. Bhat wrote:
+ if(caps->host.powerMgmt_valid) {
+ /* The PM query was successful. */
+ if(caps->host.powerMgmt) {
+ /* The host supports some PM features. */
+ unsigned int pm = caps->host.powerMgmt;
+ virBufferAddLit(&xml, "<power_management>\n");
+ while(pm) {
Our style is to use space after keywords and before opening '(' (that
is, you should be using 'if (', 'while ('); we only omit space on
function calls (your use of 'virBufferAddLit(' is correct).
+++ b/src/qemu/qemu_capabilities.c
@@ -794,6 +794,8 @@ virCapsPtr qemuCapsInit(virCapsPtr old_caps)
struct utsname utsname;
virCapsPtr caps;
int i;
+ int status = -1;
+ unsigned int pmbitmask = 0;
You don't need this temporary. Instead,...
char *xenner = NULL;
/* Really, this never fails - look at the man-page. */
@@ -824,6 +826,22 @@ virCapsPtr qemuCapsInit(virCapsPtr old_caps)
old_caps->host.cpu = NULL;
}
+ /* Add the power management features of the host */
+
+ status = virGetPMCapabilities(&pmbitmask);
+ if(status< 0) {
+ caps->host.powerMgmt_valid = false;
VIR_ALLOC guaranteed that false was already the default.
+ VIR_WARN("Failed to get host power management
capabilities");
+ } else {
+ /* The PM query succeeded. */
...you can just do the assignment in place:
if (virGetPMCapabilities(&caps->host.powerMgmt) < 0)
VIR_WARN("Failed to get host power management capabilities");
else
caps->host.powerMgmt_valid = true;
+int
+virGetPMCapabilities(unsigned int * bitmask)
Our style does not use space after '*' for pointers:
unsigned int *bitmask
+ if((path = virFindFileInPath("pm-is-supported")) ==
NULL) {
+ virUtilError(VIR_ERR_INTERNAL_ERROR,
+ "%s", _("Failed to get the path of
pm-is-supported"));
+ return -1;
+ }
Overkill - virCommand already does this check on your behalf.
+
+ /* Check support for Suspend-to-RAM (S3) */
+ cmd = virCommandNew(path);
+ virCommandAddArg(cmd, "--suspend");
+ if(virCommandRun(cmd,&status)< 0) {
+ virUtilError(VIR_ERR_INTERNAL_ERROR,
+ "%s", _("Failed to run command"
+ "'pm-is-supported --suspend'"));
Overkill - virCommand already issues a (much better) error message on
your behalf.
I'd use:
int ret = -1;
int status;
cmd = virCommandNewArgList("pm-is-supported", "--suspend", NULL);
if (virCommandRun(cmd, &status) < 0)
goto cleanup;
if (status == 0)
*bitmask |= 1U << VIR_HOST_PM_S3;
virCommandFree(cmd);
cmd = virCommandNewArgList("pm-is-supported", "--hibernate", NULL);
if (virCommandRun(cmd, &status) < 0)
goto cleanup;
if (status == 0)
*bitmask |= 1U << VIR_HOST_PM_S4;
ret = 0;
cleanup:
virCommandFree(cmd);
return ret;
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library http://libvirt.org