3:21 a.m.
On 2018年11月06日 01:19, John Ferlan wrote:
On 10/22/18 4:01 AM, Wang Huaqiang wrote:
> Add interface for resctrl monitor to determine the path.
>
> Signed-off-by: Wang Huaqiang <huaqiang.wang(a)intel.com>
> ---
> src/libvirt_private.syms | 1 +
> src/util/virresctrl.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++
> src/util/virresctrl.h | 5 ++++-
> 3 files changed, 60 insertions(+), 1 deletion(-)
>
> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
> index d2573c5..5235046 100644
> --- a/src/libvirt_private.syms
> +++ b/src/libvirt_private.syms
> @@ -2680,6 +2680,7 @@ virResctrlInfoGetCache;
> virResctrlInfoGetMonitorPrefix;
> virResctrlInfoMonFree;
> virResctrlInfoNew;
> +virResctrlMonitorDeterminePath;
> virResctrlMonitorNew;
>
>
> diff --git a/src/util/virresctrl.c b/src/util/virresctrl.c
> index 956aca8..1d0eb01 100644
> --- a/src/util/virresctrl.c
> +++ b/src/util/virresctrl.c
> @@ -2462,3 +2462,58 @@ virResctrlMonitorNew(void)
>
> return virObjectNew(virResctrlMonitorClass);
> }
> +
> +
> +/*
> + * virResctrlMonitorDeterminePath
> + *
> + * @monitor: Pointer to a resctrl monitor
> + * @machinename: Name string of the VM
> + *
> + * Determines the directory path that the underlying resctrl group will be
> + * created with.
> + *
> + * A monitor represents a directory under resource control file system,
> + * its directory path could be the same path as @monitor->alloc, could be a
> + * path of directory under 'mon_groups' of @monitor->alloc, or a path of
> + * directory under '/sys/fs/resctrl/mon_groups' if @monitor->alloc is
NULL.
> + *
> + * Returns 0 on success, -1 on error.
> + */
> +int
> +virResctrlMonitorDeterminePath(virResctrlMonitorPtr monitor,
> + const char *machinename)
> +{
> + VIR_AUTOFREE(char *) parentpath = NULL;
> +
> + if (!monitor) {
> + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> + _("Invalid resctrl monitor"));
> + return -1;
> + }
> +
> + if (monitor->path) {
> + virReportError(VIR_ERR_INTERNAL_ERROR,
> + _("Resctrl monitor path is already set to
'%s'"),
> + monitor->path);
> + return -1;
> + }
> +
> + if (monitor->id && monitor->alloc &&
monitor->alloc->id) {
> + if (STREQ(monitor->id, monitor->alloc->id)) {
> + if (VIR_STRDUP(monitor->path, monitor->alloc->path) < 0)
> + return -1;
> + return 0;
> + }
> + }
> +
> + if (virAsprintf(&parentpath, "%s/mon_groups",
monitor->alloc->path) < 0)
Just ran the changes through Coverity - because of the above
"monitor->alloc" check, Coverity notes right here that monitor->alloc
could be NULL, so I think a check prior to here would be in order,
Yes. Here exists a risk that this line you mentioned could be executed at
the condition that @monitor->alloc is empty pointer, this will cause a
crash.
such
as either before or after the monitor->path check:
if (!monitor->alloc) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Missing resctrl monitor allocation"));
return -1;
}
Putting these lines before and after the monitor->path check should be
OK for me.
(I don't find the influence made by the order. )
Then the monitor->alloc check wouldn't be necessary. Thus the above
STRDUP becomes:
if (STREQ_NULLABLE(monitor->id, monitor->alloc->id)) {
if (VIR_STRDUP(monitor->path, monitor->alloc->path) < 0)
return -1;
return 0;
}
Agree.
Thanks.
Let me know where you want it.
John
Thanks for review.
Huaqiang
> + return -1;
> +
> + monitor->path = virResctrlDeterminePath(parentpath, machinename,
> + monitor->id);
> + if (!monitor->path)
> + return -1;
> +
> + return 0;
> +}
> diff --git a/src/util/virresctrl.h b/src/util/virresctrl.h
> index eaa077d..baae554 100644
> --- a/src/util/virresctrl.h
> +++ b/src/util/virresctrl.h
> @@ -191,7 +191,10 @@ virResctrlInfoGetMonitorPrefix(virResctrlInfoPtr resctrl,
> typedef struct _virResctrlMonitor virResctrlMonitor;
> typedef virResctrlMonitor *virResctrlMonitorPtr;
>
> -
> virResctrlMonitorPtr
> virResctrlMonitorNew(void);
> +
> +int
> +virResctrlMonitorDeterminePath(virResctrlMonitorPtr monitor,
> + const char *machinename);
> #endif /* __VIR_RESCTRL_H__ */
>