[v2,19/48] xen: add sched_unit_pause_nosync() and sched_unit_unpause()

Commit Message

Jürgen Groß Aug. 9, 2019, 2:58 p.m. UTC

The credit scheduler calls vcpu_pause_nosync() and vcpu_unpause()
today. Add sched_unit_pause_nosync() and sched_unit_unpause() to
perform the same operations on scheduler units instead.

Signed-off-by: Juergen Gross <[e-mail]>
---
 xen/common/sched_credit.c  |  6 +++---
 xen/include/xen/sched-if.h | 10 ++++++++++
 2 files changed, 13 insertions(+), 3 deletions(-)

Comments

Jan Beulich Sept. 9, 2019, 1:34 p.m. UTC | #1

On 09.08.2019 16:58, Juergen Gross wrote:
> The credit scheduler calls vcpu_pause_nosync() and vcpu_unpause()
> today. Add sched_unit_pause_nosync() and sched_unit_unpause() to
> perform the same operations on scheduler units instead.

And by placing them in sched-if.h you mean to indicate that they're
not meant to be used by other than scheduler code? I ask because
the vcpu and domain counterparts are validly usable elsewhere.

Jan

Jürgen Groß Sept. 11, 2019, 2:15 p.m. UTC | #2

On 09.09.19 15:34, Jan Beulich wrote:
> On 09.08.2019 16:58, Juergen Gross wrote:
>> The credit scheduler calls vcpu_pause_nosync() and vcpu_unpause()
>> today. Add sched_unit_pause_nosync() and sched_unit_unpause() to
>> perform the same operations on scheduler units instead.
> 
> And by placing them in sched-if.h you mean to indicate that they're
> not meant to be used by other than scheduler code? I ask because
> the vcpu and domain counterparts are validly usable elsewhere.

Correct. Acting on sched_units is supposed to be done in scheduling
code only.


Juergen

Patch

diff --git a/xen/common/sched_credit.c b/xen/common/sched_credit.c
index 60eb4d3244..4ce0f7668a 100644
--- a/xen/common/sched_credit.c
+++ b/xen/common/sched_credit.c
@@ -1065,7 +1065,7 @@  csched_unit_remove(const struct scheduler *ops, struct sched_unit *unit)
     if ( test_and_clear_bit(CSCHED_FLAG_UNIT_PARKED, &svc->flags) )
     {
         SCHED_STAT_CRANK(unit_unpark);
-        vcpu_unpause(svc->unit->vcpu_list);
+        sched_unit_unpause(svc->unit);
     }
 
     spin_lock_irq(&prv->lock);
@@ -1515,7 +1515,7 @@  csched_acct(void* dummy)
                      !test_and_set_bit(CSCHED_FLAG_UNIT_PARKED, &svc->flags) )
                 {
                     SCHED_STAT_CRANK(unit_park);
-                    vcpu_pause_nosync(svc->unit->vcpu_list);
+                    sched_unit_pause_nosync(svc->unit);
                 }
 
                 /* Lower bound on credits */
@@ -1539,7 +1539,7 @@  csched_acct(void* dummy)
                      * if it is woken up here.
                      */
                     SCHED_STAT_CRANK(unit_unpark);
-                    vcpu_unpause(svc->unit->vcpu_list);
+                    sched_unit_unpause(svc->unit);
                     clear_bit(CSCHED_FLAG_UNIT_PARKED, &svc->flags);
                 }
 
diff --git a/xen/include/xen/sched-if.h b/xen/include/xen/sched-if.h
index 65fa853e90..a945fc748d 100644
--- a/xen/include/xen/sched-if.h
+++ b/xen/include/xen/sched-if.h
@@ -431,6 +431,16 @@  static inline int sched_adjust_cpupool(const struct scheduler *s,
     return s->adjust_global ? s->adjust_global(s, op) : 0;
 }
 
+static inline void sched_unit_pause_nosync(struct sched_unit *unit)
+{
+    vcpu_pause_nosync(unit->vcpu_list);
+}
+
+static inline void sched_unit_unpause(struct sched_unit *unit)
+{
+    vcpu_unpause(unit->vcpu_list);
+}
+
 #define REGISTER_SCHEDULER(x) static const struct scheduler *x##_entry \
   __used_section(".data.schedulers") = &x;