Re: 2.6.21-rc2-mm1: what about CONFIG_NO_HZ and !CONFIG_SMP ?
Le 02.03.2007 21:57, Siddha, Suresh B a écrit :
On Fri, Mar 02, 2007 at 10:12:25PM +0100, Laurent Riffard wrote:
Le 02.03.2007 12:00, Andrew Morton a écrit :
Temporarily at
http://userweb.kernel.org/~akpm/2.6.21-rc2-mm1/
Will appear later at
ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc2/2.6.21-rc2-mm1/
Got this when CONFIG_NO_HZ=y and CONFIG_SMP=n:
CC kernel/sched.o
kernel/sched.c: In function 'trigger_load_balance':
kernel/sched.c:3384: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3384: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3385: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3387: error: 'nohz' undeclared (first use in this function)
kernel/sched.c:3387: error: (Each undeclared identifier is reported only once
kernel/sched.c:3387: error: for each function it appears in.)
kernel/sched.c:3404: warning: implicit declaration of function 'resched_cpu'
kernel/sched.c:3412: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3422: error: 'struct rq' has no member named 'idle_at_tick'
make[1]: *** [kernel/sched.o] Error 1
make: *** [kernel] Error 2
Looking at kernel/sched.c, it seems CONFIG_NO_HZ should depend on CONFIG_SMP...
No. There is no such dependency. Can you please check if the below patch fixes
the compilation issue. Thanks.
Yes, it does fix the compilation issue.
thanks
~~
laurent
Move trigger_load_balance() under ifdef CONFIG_SMP.
Signed-off-by: Suresh Siddha <[EMAIL PROTECTED]>
---
diff -pNru linux-2.6.21-rc2/kernel/sched.c linux-mm/kernel/sched.c
--- linux-2.6.21-rc2/kernel/sched.c 2007-03-02 13:23:46.0 -0800
+++ linux-mm/kernel/sched.c 2007-03-02 13:26:38.0 -0800
@@ -3156,6 +3156,68 @@ static void run_rebalance_domains(struct
}
#endif
}
+
+/*
+ * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
+ *
+ * In case of CONFIG_NO_HZ, this is the place where we nominate a new
+ * idle load balancing owner or decide to stop the periodic load balancing,
+ * if the whole system is idle.
+ */
+static inline void trigger_load_balance(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+#ifdef CONFIG_NO_HZ
+ /*
+* If we were in the nohz mode recently and busy at the current
+* scheduler tick, then check if we need to nominate new idle
+* load balancer.
+*/
+ if (rq->in_nohz_recently && !rq->idle_at_tick) {
+ rq->in_nohz_recently = 0;
+
+ if (atomic_read(_balancer) == cpu) {
+ cpu_clear(cpu, nohz.cpu_mask);
+ atomic_set(_balancer, -1);
+ }
+
+ if (atomic_read(_balancer) == -1) {
+ /*
+* simple selection for now: Nominate the
+* first cpu in the nohz list to be the next
+* ilb owner.
+*
+* TBD: Traverse the sched domains and nominate
+* the nearest cpu in the nohz.cpu_mask.
+*/
+ int ilb = first_cpu(nohz.cpu_mask);
+
+ if (ilb != NR_CPUS)
+ resched_cpu(ilb);
+ }
+ }
+
+ /*
+* If this cpu is idle and doing idle load balancing for all the
+* cpus with ticks stopped, is it time for that to stop?
+*/
+ if (rq->idle_at_tick && atomic_read(_balancer) == cpu &&
+ cpus_weight(nohz.cpu_mask) == num_online_cpus()) {
+ resched_cpu(cpu);
+ return;
+ }
+
+ /*
+* If this cpu is idle and the idle load balancing is done by
+* someone else, then no need raise the SCHED_SOFTIRQ
+*/
+ if (rq->idle_at_tick && atomic_read(_balancer) != cpu &&
+ cpu_isset(cpu, nohz.cpu_mask))
+ return;
+#endif
+ if (time_after_eq(jiffies, rq->next_balance))
+ raise_softirq(SCHED_SOFTIRQ);
+}
#else
/*
* on UP we do not need to balance between CPUs:
@@ -3366,68 +3428,6 @@ out_unlock:
}
/*
- * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
- *
- * In case of CONFIG_NO_HZ, this is the place where we nominate a new
- * idle load balancing owner or decide to stop the periodic load balancing,
- * if the whole system is idle.
- */
-static inline void trigger_load_balance(int cpu)
-{
- struct rq *rq = cpu_rq(cpu);
-#ifdef CONFIG_NO_HZ
- /*
-* If we were in the nohz mode recently and busy at the current
-* scheduler tick, then check if we need to nominate new idle
-* load balancer.
-*/
- if (rq->in_nohz_recently && !rq->idle_at_tick) {
- rq->in_nohz_recently = 0;
-
- if (atomic_read(_balancer) == cpu) {
- cpu_clear(cpu, nohz.cpu_mask);
-
Re: 2.6.21-rc2-mm1: what about CONFIG_NO_HZ and !CONFIG_SMP ?
On Fri, Mar 02, 2007 at 10:12:25PM +0100, Laurent Riffard wrote:
> Le 02.03.2007 12:00, Andrew Morton a écrit :
> > Temporarily at
> >
> > http://userweb.kernel.org/~akpm/2.6.21-rc2-mm1/
> >
> > Will appear later at
> >
> >
> > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc2/2.6.21-rc2-mm1/
>
> Got this when CONFIG_NO_HZ=y and CONFIG_SMP=n:
>
> CC kernel/sched.o
> kernel/sched.c: In function 'trigger_load_balance':
> kernel/sched.c:3384: error: 'struct rq' has no member named 'in_nohz_recently'
> kernel/sched.c:3384: error: 'struct rq' has no member named 'idle_at_tick'
> kernel/sched.c:3385: error: 'struct rq' has no member named 'in_nohz_recently'
> kernel/sched.c:3387: error: 'nohz' undeclared (first use in this function)
> kernel/sched.c:3387: error: (Each undeclared identifier is reported only once
> kernel/sched.c:3387: error: for each function it appears in.)
> kernel/sched.c:3404: warning: implicit declaration of function 'resched_cpu'
> kernel/sched.c:3412: error: 'struct rq' has no member named 'idle_at_tick'
> kernel/sched.c:3422: error: 'struct rq' has no member named 'idle_at_tick'
> make[1]: *** [kernel/sched.o] Error 1
> make: *** [kernel] Error 2
>
> Looking at kernel/sched.c, it seems CONFIG_NO_HZ should depend on
> CONFIG_SMP...
No. There is no such dependency. Can you please check if the below patch fixes
the compilation issue. Thanks.
---
Move trigger_load_balance() under ifdef CONFIG_SMP.
Signed-off-by: Suresh Siddha <[EMAIL PROTECTED]>
---
diff -pNru linux-2.6.21-rc2/kernel/sched.c linux-mm/kernel/sched.c
--- linux-2.6.21-rc2/kernel/sched.c 2007-03-02 13:23:46.0 -0800
+++ linux-mm/kernel/sched.c 2007-03-02 13:26:38.0 -0800
@@ -3156,6 +3156,68 @@ static void run_rebalance_domains(struct
}
#endif
}
+
+/*
+ * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
+ *
+ * In case of CONFIG_NO_HZ, this is the place where we nominate a new
+ * idle load balancing owner or decide to stop the periodic load balancing,
+ * if the whole system is idle.
+ */
+static inline void trigger_load_balance(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+#ifdef CONFIG_NO_HZ
+ /*
+* If we were in the nohz mode recently and busy at the current
+* scheduler tick, then check if we need to nominate new idle
+* load balancer.
+*/
+ if (rq->in_nohz_recently && !rq->idle_at_tick) {
+ rq->in_nohz_recently = 0;
+
+ if (atomic_read(_balancer) == cpu) {
+ cpu_clear(cpu, nohz.cpu_mask);
+ atomic_set(_balancer, -1);
+ }
+
+ if (atomic_read(_balancer) == -1) {
+ /*
+* simple selection for now: Nominate the
+* first cpu in the nohz list to be the next
+* ilb owner.
+*
+* TBD: Traverse the sched domains and nominate
+* the nearest cpu in the nohz.cpu_mask.
+*/
+ int ilb = first_cpu(nohz.cpu_mask);
+
+ if (ilb != NR_CPUS)
+ resched_cpu(ilb);
+ }
+ }
+
+ /*
+* If this cpu is idle and doing idle load balancing for all the
+* cpus with ticks stopped, is it time for that to stop?
+*/
+ if (rq->idle_at_tick && atomic_read(_balancer) == cpu &&
+ cpus_weight(nohz.cpu_mask) == num_online_cpus()) {
+ resched_cpu(cpu);
+ return;
+ }
+
+ /*
+* If this cpu is idle and the idle load balancing is done by
+* someone else, then no need raise the SCHED_SOFTIRQ
+*/
+ if (rq->idle_at_tick && atomic_read(_balancer) != cpu &&
+ cpu_isset(cpu, nohz.cpu_mask))
+ return;
+#endif
+ if (time_after_eq(jiffies, rq->next_balance))
+ raise_softirq(SCHED_SOFTIRQ);
+}
#else
/*
* on UP we do not need to balance between CPUs:
@@ -3366,68 +3428,6 @@ out_unlock:
}
/*
- * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
- *
- * In case of CONFIG_NO_HZ, this is the place where we nominate a new
- * idle load balancing owner or decide to stop the periodic load balancing,
- * if the whole system is idle.
- */
-static inline void trigger_load_balance(int cpu)
-{
- struct rq *rq = cpu_rq(cpu);
-#ifdef CONFIG_NO_HZ
- /*
-* If we were in the nohz mode recently and busy at the current
-* scheduler tick, then check if we need to nominate new idle
-* load balancer.
-*/
- if (rq->in_nohz_recently && !rq->idle_at_tick) {
- rq->in_nohz_recently = 0;
-
- if (atomic_read(_balancer) == cpu) {
- cpu_clear(cpu, nohz.cpu_mask);
- atomic_set(_balancer,
Re: 2.6.21-rc2-mm1: what about CONFIG_NO_HZ and !CONFIG_SMP ?
Le 02.03.2007 12:00, Andrew Morton a écrit :
Temporarily at
http://userweb.kernel.org/~akpm/2.6.21-rc2-mm1/
Will appear later at
ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc2/2.6.21-rc2-mm1/
Got this when CONFIG_NO_HZ=y and CONFIG_SMP=n:
CC kernel/sched.o
kernel/sched.c: In function 'trigger_load_balance':
kernel/sched.c:3384: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3384: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3385: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3387: error: 'nohz' undeclared (first use in this function)
kernel/sched.c:3387: error: (Each undeclared identifier is reported only once
kernel/sched.c:3387: error: for each function it appears in.)
kernel/sched.c:3404: warning: implicit declaration of function 'resched_cpu'
kernel/sched.c:3412: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3422: error: 'struct rq' has no member named 'idle_at_tick'
make[1]: *** [kernel/sched.o] Error 1
make: *** [kernel] Error 2
Looking at kernel/sched.c, it seems CONFIG_NO_HZ should depend on CONFIG_SMP...
238 struct rq {
239 spinlock_t lock;
240
241 /*
242 * nr_running and cpu_load should be in the same cacheline because
243 * remote CPUs use both these fields when doing load calculation.
244 */
245 unsigned long nr_running;
246 unsigned long raw_weighted_load;
247 #ifdef CONFIG_SMP
248 unsigned long cpu_load[3];
249 unsigned char idle_at_tick;
250 #ifdef CONFIG_NO_HZ
251 unsigned char in_nohz_recently;
252 #endif
253 #endif
254 unsigned long long nr_switches;
~~
laurent
-
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Re: 2.6.21-rc2-mm1: what about CONFIG_NO_HZ and !CONFIG_SMP ?
Le 02.03.2007 12:00, Andrew Morton a écrit :
Temporarily at
http://userweb.kernel.org/~akpm/2.6.21-rc2-mm1/
Will appear later at
ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc2/2.6.21-rc2-mm1/
Got this when CONFIG_NO_HZ=y and CONFIG_SMP=n:
CC kernel/sched.o
kernel/sched.c: In function 'trigger_load_balance':
kernel/sched.c:3384: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3384: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3385: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3387: error: 'nohz' undeclared (first use in this function)
kernel/sched.c:3387: error: (Each undeclared identifier is reported only once
kernel/sched.c:3387: error: for each function it appears in.)
kernel/sched.c:3404: warning: implicit declaration of function 'resched_cpu'
kernel/sched.c:3412: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3422: error: 'struct rq' has no member named 'idle_at_tick'
make[1]: *** [kernel/sched.o] Error 1
make: *** [kernel] Error 2
Looking at kernel/sched.c, it seems CONFIG_NO_HZ should depend on CONFIG_SMP...
238 struct rq {
239 spinlock_t lock;
240
241 /*
242 * nr_running and cpu_load should be in the same cacheline because
243 * remote CPUs use both these fields when doing load calculation.
244 */
245 unsigned long nr_running;
246 unsigned long raw_weighted_load;
247 #ifdef CONFIG_SMP
248 unsigned long cpu_load[3];
249 unsigned char idle_at_tick;
250 #ifdef CONFIG_NO_HZ
251 unsigned char in_nohz_recently;
252 #endif
253 #endif
254 unsigned long long nr_switches;
~~
laurent
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: 2.6.21-rc2-mm1: what about CONFIG_NO_HZ and !CONFIG_SMP ?
On Fri, Mar 02, 2007 at 10:12:25PM +0100, Laurent Riffard wrote:
Le 02.03.2007 12:00, Andrew Morton a écrit :
Temporarily at
http://userweb.kernel.org/~akpm/2.6.21-rc2-mm1/
Will appear later at
ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc2/2.6.21-rc2-mm1/
Got this when CONFIG_NO_HZ=y and CONFIG_SMP=n:
CC kernel/sched.o
kernel/sched.c: In function 'trigger_load_balance':
kernel/sched.c:3384: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3384: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3385: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3387: error: 'nohz' undeclared (first use in this function)
kernel/sched.c:3387: error: (Each undeclared identifier is reported only once
kernel/sched.c:3387: error: for each function it appears in.)
kernel/sched.c:3404: warning: implicit declaration of function 'resched_cpu'
kernel/sched.c:3412: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3422: error: 'struct rq' has no member named 'idle_at_tick'
make[1]: *** [kernel/sched.o] Error 1
make: *** [kernel] Error 2
Looking at kernel/sched.c, it seems CONFIG_NO_HZ should depend on
CONFIG_SMP...
No. There is no such dependency. Can you please check if the below patch fixes
the compilation issue. Thanks.
---
Move trigger_load_balance() under ifdef CONFIG_SMP.
Signed-off-by: Suresh Siddha [EMAIL PROTECTED]
---
diff -pNru linux-2.6.21-rc2/kernel/sched.c linux-mm/kernel/sched.c
--- linux-2.6.21-rc2/kernel/sched.c 2007-03-02 13:23:46.0 -0800
+++ linux-mm/kernel/sched.c 2007-03-02 13:26:38.0 -0800
@@ -3156,6 +3156,68 @@ static void run_rebalance_domains(struct
}
#endif
}
+
+/*
+ * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
+ *
+ * In case of CONFIG_NO_HZ, this is the place where we nominate a new
+ * idle load balancing owner or decide to stop the periodic load balancing,
+ * if the whole system is idle.
+ */
+static inline void trigger_load_balance(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+#ifdef CONFIG_NO_HZ
+ /*
+* If we were in the nohz mode recently and busy at the current
+* scheduler tick, then check if we need to nominate new idle
+* load balancer.
+*/
+ if (rq-in_nohz_recently !rq-idle_at_tick) {
+ rq-in_nohz_recently = 0;
+
+ if (atomic_read(nohz.load_balancer) == cpu) {
+ cpu_clear(cpu, nohz.cpu_mask);
+ atomic_set(nohz.load_balancer, -1);
+ }
+
+ if (atomic_read(nohz.load_balancer) == -1) {
+ /*
+* simple selection for now: Nominate the
+* first cpu in the nohz list to be the next
+* ilb owner.
+*
+* TBD: Traverse the sched domains and nominate
+* the nearest cpu in the nohz.cpu_mask.
+*/
+ int ilb = first_cpu(nohz.cpu_mask);
+
+ if (ilb != NR_CPUS)
+ resched_cpu(ilb);
+ }
+ }
+
+ /*
+* If this cpu is idle and doing idle load balancing for all the
+* cpus with ticks stopped, is it time for that to stop?
+*/
+ if (rq-idle_at_tick atomic_read(nohz.load_balancer) == cpu
+ cpus_weight(nohz.cpu_mask) == num_online_cpus()) {
+ resched_cpu(cpu);
+ return;
+ }
+
+ /*
+* If this cpu is idle and the idle load balancing is done by
+* someone else, then no need raise the SCHED_SOFTIRQ
+*/
+ if (rq-idle_at_tick atomic_read(nohz.load_balancer) != cpu
+ cpu_isset(cpu, nohz.cpu_mask))
+ return;
+#endif
+ if (time_after_eq(jiffies, rq-next_balance))
+ raise_softirq(SCHED_SOFTIRQ);
+}
#else
/*
* on UP we do not need to balance between CPUs:
@@ -3366,68 +3428,6 @@ out_unlock:
}
/*
- * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
- *
- * In case of CONFIG_NO_HZ, this is the place where we nominate a new
- * idle load balancing owner or decide to stop the periodic load balancing,
- * if the whole system is idle.
- */
-static inline void trigger_load_balance(int cpu)
-{
- struct rq *rq = cpu_rq(cpu);
-#ifdef CONFIG_NO_HZ
- /*
-* If we were in the nohz mode recently and busy at the current
-* scheduler tick, then check if we need to nominate new idle
-* load balancer.
-*/
- if (rq-in_nohz_recently !rq-idle_at_tick) {
- rq-in_nohz_recently = 0;
-
- if (atomic_read(nohz.load_balancer) == cpu) {
- cpu_clear(cpu, nohz.cpu_mask);
-
Re: 2.6.21-rc2-mm1: what about CONFIG_NO_HZ and !CONFIG_SMP ?
Le 02.03.2007 21:57, Siddha, Suresh B a écrit :
On Fri, Mar 02, 2007 at 10:12:25PM +0100, Laurent Riffard wrote:
Le 02.03.2007 12:00, Andrew Morton a écrit :
Temporarily at
http://userweb.kernel.org/~akpm/2.6.21-rc2-mm1/
Will appear later at
ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc2/2.6.21-rc2-mm1/
Got this when CONFIG_NO_HZ=y and CONFIG_SMP=n:
CC kernel/sched.o
kernel/sched.c: In function 'trigger_load_balance':
kernel/sched.c:3384: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3384: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3385: error: 'struct rq' has no member named 'in_nohz_recently'
kernel/sched.c:3387: error: 'nohz' undeclared (first use in this function)
kernel/sched.c:3387: error: (Each undeclared identifier is reported only once
kernel/sched.c:3387: error: for each function it appears in.)
kernel/sched.c:3404: warning: implicit declaration of function 'resched_cpu'
kernel/sched.c:3412: error: 'struct rq' has no member named 'idle_at_tick'
kernel/sched.c:3422: error: 'struct rq' has no member named 'idle_at_tick'
make[1]: *** [kernel/sched.o] Error 1
make: *** [kernel] Error 2
Looking at kernel/sched.c, it seems CONFIG_NO_HZ should depend on CONFIG_SMP...
No. There is no such dependency. Can you please check if the below patch fixes
the compilation issue. Thanks.
Yes, it does fix the compilation issue.
thanks
~~
laurent
Move trigger_load_balance() under ifdef CONFIG_SMP.
Signed-off-by: Suresh Siddha [EMAIL PROTECTED]
---
diff -pNru linux-2.6.21-rc2/kernel/sched.c linux-mm/kernel/sched.c
--- linux-2.6.21-rc2/kernel/sched.c 2007-03-02 13:23:46.0 -0800
+++ linux-mm/kernel/sched.c 2007-03-02 13:26:38.0 -0800
@@ -3156,6 +3156,68 @@ static void run_rebalance_domains(struct
}
#endif
}
+
+/*
+ * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
+ *
+ * In case of CONFIG_NO_HZ, this is the place where we nominate a new
+ * idle load balancing owner or decide to stop the periodic load balancing,
+ * if the whole system is idle.
+ */
+static inline void trigger_load_balance(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+#ifdef CONFIG_NO_HZ
+ /*
+* If we were in the nohz mode recently and busy at the current
+* scheduler tick, then check if we need to nominate new idle
+* load balancer.
+*/
+ if (rq-in_nohz_recently !rq-idle_at_tick) {
+ rq-in_nohz_recently = 0;
+
+ if (atomic_read(nohz.load_balancer) == cpu) {
+ cpu_clear(cpu, nohz.cpu_mask);
+ atomic_set(nohz.load_balancer, -1);
+ }
+
+ if (atomic_read(nohz.load_balancer) == -1) {
+ /*
+* simple selection for now: Nominate the
+* first cpu in the nohz list to be the next
+* ilb owner.
+*
+* TBD: Traverse the sched domains and nominate
+* the nearest cpu in the nohz.cpu_mask.
+*/
+ int ilb = first_cpu(nohz.cpu_mask);
+
+ if (ilb != NR_CPUS)
+ resched_cpu(ilb);
+ }
+ }
+
+ /*
+* If this cpu is idle and doing idle load balancing for all the
+* cpus with ticks stopped, is it time for that to stop?
+*/
+ if (rq-idle_at_tick atomic_read(nohz.load_balancer) == cpu
+ cpus_weight(nohz.cpu_mask) == num_online_cpus()) {
+ resched_cpu(cpu);
+ return;
+ }
+
+ /*
+* If this cpu is idle and the idle load balancing is done by
+* someone else, then no need raise the SCHED_SOFTIRQ
+*/
+ if (rq-idle_at_tick atomic_read(nohz.load_balancer) != cpu
+ cpu_isset(cpu, nohz.cpu_mask))
+ return;
+#endif
+ if (time_after_eq(jiffies, rq-next_balance))
+ raise_softirq(SCHED_SOFTIRQ);
+}
#else
/*
* on UP we do not need to balance between CPUs:
@@ -3366,68 +3428,6 @@ out_unlock:
}
/*
- * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
- *
- * In case of CONFIG_NO_HZ, this is the place where we nominate a new
- * idle load balancing owner or decide to stop the periodic load balancing,
- * if the whole system is idle.
- */
-static inline void trigger_load_balance(int cpu)
-{
- struct rq *rq = cpu_rq(cpu);
-#ifdef CONFIG_NO_HZ
- /*
-* If we were in the nohz mode recently and busy at the current
-* scheduler tick, then check if we need to nominate new idle
-* load balancer.
-*/
- if (rq-in_nohz_recently !rq-idle_at_tick) {
- rq-in_nohz_recently = 0;
-
- if (atomic_read(nohz.load_balancer) == cpu) {
-
