[v8,for,Xen,4.7,2/4] libxc: enable per-VCPU parameter for RTDS

Commit Message

Chong Li March 18, 2016, 9:26 p.m. UTC

Add xc_sched_rtds_vcpu_get/set functions to interact with
Xen to get/set a domain's per-VCPU parameters.

Signed-off-by: Chong Li <[e-mail]>
Signed-off-by: Meng Xu <[e-mail]>
Signed-off-by: Sisu Xi <[e-mail]>

---
Changes on PATCH v6:
1) Resolve some coding sytle issues

Changes on PATCH v5:
1) In xc_sched_rtds_vcpu_get/set, re-issueing the hypercall
if it is preempted.

Changes on PATCH v4:
1) Minor modifications on the function parameters.

Changes on PATCH v2:
1) Minor modifications due to the change of struct xen_domctl_scheduler_op.

CC: <[e-mail]>
CC: <[e-mail]>
CC: <[e-mail]>
CC: <[e-mail]>
CC: <[e-mail]>
CC: <[e-mail]>

---
 tools/libxc/include/xenctrl.h |  8 +++++
 tools/libxc/xc_rt.c           | 68 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 76 insertions(+)

Comments

Dario Faggioli March 29, 2016, 5:08 p.m. UTC | #1

On Fri, 2016-03-18 at 16:26 -0500, Chong Li wrote:
> Add xc_sched_rtds_vcpu_get/set functions to interact with
> Xen to get/set a domain's per-VCPU parameters.
> 
> Signed-off-by: Chong Li <[e-mail]>
> Signed-off-by: Meng Xu <[e-mail]>
> Signed-off-by: Sisu Xi <[e-mail]>
> 
> ---
> Changes on PATCH v6:
> 1) Resolve some coding sytle issues
> 
You did not mention any chage since v7, but it looks like you did the
changes I suggested.

That should have been mentioned, if only, to help people figuring out
that it's the only thing that actually changed.

Also, Wei said:

Acked-by: Wei Liu <[e-mail]>

And I said that, if you fixed the pointless initialization of rc, you
could add:

Reviewed-by: Dario Faggioli <[e-mail]>

I think both still applies. Maybe it was ok to neglect Wei's Ack, since
you changed the subject line, which is important. But you should say
so, and catch his attention on this, so he can re-Ack the patch (if he
wants).

My tag, for sure, still applies, as I explicitly said so, and so you
should have put it in this version, to speedup review/commit.

In any case, I'm re-issueing it:

Reviewed-by: Dario Faggioli <[e-mail]>

Please, stick it below the S-o-b tags in next version.

Thanks and Regards,
Dario

Wei Liu March 31, 2016, 4:59 p.m. UTC | #2

On Fri, Mar 18, 2016 at 04:26:23PM -0500, Chong Li wrote:
> Add xc_sched_rtds_vcpu_get/set functions to interact with
> Xen to get/set a domain's per-VCPU parameters.
> 
> Signed-off-by: Chong Li <[e-mail]>
> Signed-off-by: Meng Xu <[e-mail]>
> Signed-off-by: Sisu Xi <[e-mail]>
> 

Acked-by: Wei Liu <[e-mail]>

Patch

diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index 01a6dda..4567585 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -893,6 +893,14 @@  int xc_sched_rtds_domain_set(xc_interface *xch,
 int xc_sched_rtds_domain_get(xc_interface *xch,
                             uint32_t domid,
                             struct xen_domctl_sched_rtds *sdom);
+int xc_sched_rtds_vcpu_set(xc_interface *xch,
+                           uint32_t domid,
+                           struct xen_domctl_schedparam_vcpu *vcpus,
+                           uint32_t num_vcpus);
+int xc_sched_rtds_vcpu_get(xc_interface *xch,
+                           uint32_t domid,
+                           struct xen_domctl_schedparam_vcpu *vcpus,
+                           uint32_t num_vcpus);
 
 int
 xc_sched_arinc653_schedule_set(
diff --git a/tools/libxc/xc_rt.c b/tools/libxc/xc_rt.c
index d59e5ce..221d17f 100644
--- a/tools/libxc/xc_rt.c
+++ b/tools/libxc/xc_rt.c
@@ -62,3 +62,71 @@  int xc_sched_rtds_domain_get(xc_interface *xch,
 
     return rc;
 }
+
+int xc_sched_rtds_vcpu_set(xc_interface *xch,
+                           uint32_t domid,
+                           struct xen_domctl_schedparam_vcpu *vcpus,
+                           uint32_t num_vcpus)
+{
+    int rc;
+    unsigned processed = 0;
+    DECLARE_DOMCTL;
+    DECLARE_HYPERCALL_BOUNCE(vcpus, sizeof(*vcpus) * num_vcpus,
+                             XC_HYPERCALL_BUFFER_BOUNCE_IN);
+
+    if ( xc_hypercall_bounce_pre(xch, vcpus) )
+        return -1;
+
+    domctl.cmd = XEN_DOMCTL_scheduler_op;
+    domctl.domain = (domid_t) domid;
+    domctl.u.scheduler_op.sched_id = XEN_SCHEDULER_RTDS;
+    domctl.u.scheduler_op.cmd = XEN_DOMCTL_SCHEDOP_putvcpuinfo;
+
+    while ( processed < num_vcpus )
+    {
+        domctl.u.scheduler_op.u.v.nr_vcpus = num_vcpus - processed;
+        set_xen_guest_handle_offset(domctl.u.scheduler_op.u.v.vcpus, vcpus,
+                                    processed);
+        if ( (rc = do_domctl(xch, &domctl)) != 0 )
+            break;
+        processed += domctl.u.scheduler_op.u.v.nr_vcpus;
+    }
+
+    xc_hypercall_bounce_post(xch, vcpus);
+
+    return rc;
+}
+
+int xc_sched_rtds_vcpu_get(xc_interface *xch,
+                           uint32_t domid,
+                           struct xen_domctl_schedparam_vcpu *vcpus,
+                           uint32_t num_vcpus)
+{
+    int rc;
+    unsigned processed = 0;
+    DECLARE_DOMCTL;
+    DECLARE_HYPERCALL_BOUNCE(vcpus, sizeof(*vcpus) * num_vcpus,
+                             XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
+
+    if ( xc_hypercall_bounce_pre(xch, vcpus) )
+        return -1;
+
+    domctl.cmd = XEN_DOMCTL_scheduler_op;
+    domctl.domain = (domid_t) domid;
+    domctl.u.scheduler_op.sched_id = XEN_SCHEDULER_RTDS;
+    domctl.u.scheduler_op.cmd = XEN_DOMCTL_SCHEDOP_getvcpuinfo;
+
+    while ( processed < num_vcpus )
+    {
+        domctl.u.scheduler_op.u.v.nr_vcpus = num_vcpus - processed;
+        set_xen_guest_handle_offset(domctl.u.scheduler_op.u.v.vcpus, vcpus,
+                                    processed);
+        if ( (rc = do_domctl(xch, &domctl)) != 0 )
+            break;
+        processed += domctl.u.scheduler_op.u.v.nr_vcpus;
+    }
+
+    xc_hypercall_bounce_post(xch, vcpus);
+
+    return rc;
+}