Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched

* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
  [PATCH] sched: implement cpu_clock(cpu) high-speed time source
  [PATCH] sched: fix the all pinned logic in load_balance_newidle()
  [PATCH] sched: fix newly idle load balance in case of SMT
  [PATCH] sched: sched_cacheflush is now unused

18 files changed, 33 insertions, 154 deletions

diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c
index 4d9864cc92c..cf06fe79904 100644
--- a/arch/ia64/kernel/setup.c
+++ b/arch/ia64/kernel/setup.c
@@ -980,15 +980,6 @@ cpu_init (void)
 	pm_idle = default_idle;
 }
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- */
-void sched_cacheflush(void)
-{
-	ia64_sal_cache_flush(3);
-}
-
 void __init
 check_bugs (void)
 {
diff --git a/include/asm-alpha/system.h b/include/asm-alpha/system.h
index cf1021a97b2..620c4d86cbf 100644
--- a/include/asm-alpha/system.h
+++ b/include/asm-alpha/system.h
@@ -139,16 +139,6 @@ extern void halt(void) __attribute__((noreturn));
 struct task_struct;
 extern struct task_struct *alpha_switch_to(unsigned long, struct task_struct*);
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 #define imb() \
 __asm__ __volatile__ ("call_pal %0 #imb" : : "i" (PAL_imb) : "memory")
 
diff --git a/include/asm-arm/system.h b/include/asm-arm/system.h
index 6f8e6a69dc5..94ea8c6dc1a 100644
--- a/include/asm-arm/system.h
+++ b/include/asm-arm/system.h
@@ -254,16 +254,6 @@ do {									\
 	last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));	\
 } while (0)
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 #if defined(CONFIG_CPU_SA1100) || defined(CONFIG_CPU_SA110)
 /*
  * On the StrongARM, "swp" is terminally broken since it bypasses the
diff --git a/include/asm-arm26/system.h b/include/asm-arm26/system.h
index 4703593b3bb..e09da5ff1f5 100644
--- a/include/asm-arm26/system.h
+++ b/include/asm-arm26/system.h
@@ -110,16 +110,6 @@ do {									\
 } while (0)
 
 /*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
-/*
  * Save the current interrupt enable state & disable IRQs
  */
 #define local_irq_save(x)                               \
diff --git a/include/asm-i386/system.h b/include/asm-i386/system.h
index 94ed3686a5f..609756c6167 100644
--- a/include/asm-i386/system.h
+++ b/include/asm-i386/system.h
@@ -310,15 +310,6 @@ void enable_hlt(void);
 extern int es7000_plat;
 void cpu_idle_wait(void);
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible:
- */
-static inline void sched_cacheflush(void)
-{
-	wbinvd();
-}
-
 extern unsigned long arch_align_stack(unsigned long sp);
 extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
 
diff --git a/include/asm-ia64/system.h b/include/asm-ia64/system.h
index 384fbf7f2a0..91bb8e00066 100644
--- a/include/asm-ia64/system.h
+++ b/include/asm-ia64/system.h
@@ -259,7 +259,6 @@ extern void ia64_load_extra (struct task_struct *task);
 #define ia64_platform_is(x) (strcmp(x, platform_name) == 0)
 
 void cpu_idle_wait(void);
-void sched_cacheflush(void);
 
 #define arch_align_stack(x) (x)
 
diff --git a/include/asm-m32r/system.h b/include/asm-m32r/system.h
index 8ee73d3f316..2365de5c295 100644
--- a/include/asm-m32r/system.h
+++ b/include/asm-m32r/system.h
@@ -54,16 +54,6 @@
 	); \
 } while(0)
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 /* Interrupt Control */
 #if !defined(CONFIG_CHIP_M32102) && !defined(CONFIG_CHIP_M32104)
 #define local_irq_enable() \
diff --git a/include/asm-mips/system.h b/include/asm-mips/system.h
index 46bdb3f566f..76339165bc2 100644
--- a/include/asm-mips/system.h
+++ b/include/asm-mips/system.h
@@ -71,16 +71,6 @@ do {									\
 		write_c0_userlocal(task_thread_info(current)->tp_value);\
 } while(0)
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 static inline unsigned long __xchg_u32(volatile int * m, unsigned int val)
 {
 	__u32 retval;
diff --git a/include/asm-parisc/system.h b/include/asm-parisc/system.h
index 21fbfc5afd0..ee80c920b46 100644
--- a/include/asm-parisc/system.h
+++ b/include/asm-parisc/system.h
@@ -48,17 +48,6 @@ extern struct task_struct *_switch_to(struct task_struct *, struct task_struct *
 	(last) = _switch_to(prev, next);			\
 } while(0)
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
-
 /* interrupt control */
 #define local_save_flags(x)	__asm__ __volatile__("ssm 0, %0" : "=r" (x) : : "memory")
 #define local_irq_disable()	__asm__ __volatile__("rsm %0,%%r0\n" : : "i" (PSW_I) : "memory" )
diff --git a/include/asm-powerpc/system.h b/include/asm-powerpc/system.h
index 32aa42b748b..41520b7a7b7 100644
--- a/include/asm-powerpc/system.h
+++ b/include/asm-powerpc/system.h
@@ -184,16 +184,6 @@ struct thread_struct;
 extern struct task_struct *_switch(struct thread_struct *prev,
 				   struct thread_struct *next);
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 extern unsigned int rtas_data;
 extern int mem_init_done;	/* set on boot once kmalloc can be called */
 extern unsigned long memory_limit;
diff --git a/include/asm-ppc/system.h b/include/asm-ppc/system.h
index d84a3cf4d03..f1311a8f310 100644
--- a/include/asm-ppc/system.h
+++ b/include/asm-ppc/system.h
@@ -129,16 +129,6 @@ extern struct task_struct *__switch_to(struct task_struct *,
 	struct task_struct *);
 #define switch_to(prev, next, last)	((last) = __switch_to((prev), (next)))
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 struct thread_struct;
 extern struct task_struct *_switch(struct thread_struct *prev,
 				   struct thread_struct *next);
diff --git a/include/asm-s390/system.h b/include/asm-s390/system.h
index bbe137c3ed6..64a3cd05cae 100644
--- a/include/asm-s390/system.h
+++ b/include/asm-s390/system.h
@@ -97,16 +97,6 @@ static inline void restore_access_regs(unsigned int *acrs)
 	prev = __switch_to(prev,next);					     \
 } while (0)
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
 extern void account_vtime(struct task_struct *);
 extern void account_tick_vtime(struct task_struct *);
diff --git a/include/asm-sh/system.h b/include/asm-sh/system.h
index 7c75045ae22..24504253720 100644
--- a/include/asm-sh/system.h
+++ b/include/asm-sh/system.h
@@ -64,16 +64,6 @@ struct task_struct *__switch_to(struct task_struct *prev,
 	last = __last;							\
 } while (0)
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 #ifdef CONFIG_CPU_SH4A
 #define __icbi()			\
 {					\
diff --git a/include/asm-sparc/system.h b/include/asm-sparc/system.h
index 8b4e23b3bb3..d1a2572e3f5 100644
--- a/include/asm-sparc/system.h
+++ b/include/asm-sparc/system.h
@@ -165,16 +165,6 @@ extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
 	} while(0)
 
 /*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
-/*
  * Changing the IRQ level on the Sparc.
  */
 extern void local_irq_restore(unsigned long);
diff --git a/include/asm-sparc64/system.h b/include/asm-sparc64/system.h
index 8ba380ec6da..409067408ee 100644
--- a/include/asm-sparc64/system.h
+++ b/include/asm-sparc64/system.h
@@ -204,16 +204,6 @@ do {	if (test_thread_flag(TIF_PERFCTR)) {				\
 	}								\
 } while(0)
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- *
- * TODO: fill this in!
- */
-static inline void sched_cacheflush(void)
-{
-}
-
 static inline unsigned long xchg32(__volatile__ unsigned int *m, unsigned int val)
 {
 	unsigned long tmp1, tmp2;
diff --git a/include/asm-x86_64/system.h b/include/asm-x86_64/system.h
index ead9f9a5623..e4f246d62c4 100644
--- a/include/asm-x86_64/system.h
+++ b/include/asm-x86_64/system.h
@@ -111,15 +111,6 @@ static inline void write_cr4(unsigned long val)
 #define wbinvd() \
 	__asm__ __volatile__ ("wbinvd": : :"memory");
 
-/*
- * On SMP systems, when the scheduler does migration-cost autodetection,
- * it needs a way to flush as much of the CPU's caches as possible.
- */
-static inline void sched_cacheflush(void)
-{
-	wbinvd();
-}
-
 #endif	/* __KERNEL__ */
 
 #define nop() __asm__ __volatile__ ("nop")
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 94f624aef01..33b9b4841ee 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1348,6 +1348,13 @@ static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
 #endif
 
 extern unsigned long long sched_clock(void);
+
+/*
+ * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
+ * clock constructed from sched_clock():
+ */
+extern unsigned long long cpu_clock(int cpu);
+
 extern unsigned long long
 task_sched_runtime(struct task_struct *task);
 
diff --git a/kernel/sched.c b/kernel/sched.c
index 645256b228c..93cf241cfbe 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -379,6 +379,23 @@ static inline unsigned long long rq_clock(struct rq *rq)
 #define task_rq(p)		cpu_rq(task_cpu(p))
 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
 
+/*
+ * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
+ * clock constructed from sched_clock():
+ */
+unsigned long long cpu_clock(int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long long now;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rq->lock, flags);
+	now = rq_clock(rq);
+	spin_unlock_irqrestore(&rq->lock, flags);
+
+	return now;
+}
+
 #ifdef CONFIG_FAIR_GROUP_SCHED
 /* Change a task's ->cfs_rq if it moves across CPUs */
 static inline void set_task_cfs_rq(struct task_struct *p)
@@ -2235,7 +2252,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
 
 			rq = cpu_rq(i);
 
-			if (*sd_idle && !idle_cpu(i))
+			if (*sd_idle && rq->nr_running)
 				*sd_idle = 0;
 
 			/* Bias balancing toward cpus of our domain */
@@ -2257,9 +2274,11 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
 		/*
 		 * First idle cpu or the first cpu(busiest) in this sched group
 		 * is eligible for doing load balancing at this and above
-		 * domains.
+		 * domains. In the newly idle case, we will allow all the cpu's
+		 * to do the newly idle load balance.
 		 */
-		if (local_group && balance_cpu != this_cpu && balance) {
+		if (idle != CPU_NEWLY_IDLE && local_group &&
+		    balance_cpu != this_cpu && balance) {
 			*balance = 0;
 			goto ret;
 		}
@@ -2677,6 +2696,7 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd)
 	unsigned long imbalance;
 	int nr_moved = 0;
 	int sd_idle = 0;
+	int all_pinned = 0;
 	cpumask_t cpus = CPU_MASK_ALL;
 
 	/*
@@ -2715,10 +2735,11 @@ redo:
 		double_lock_balance(this_rq, busiest);
 		nr_moved = move_tasks(this_rq, this_cpu, busiest,
 					minus_1_or_zero(busiest->nr_running),
-					imbalance, sd, CPU_NEWLY_IDLE, NULL);
+					imbalance, sd, CPU_NEWLY_IDLE,
+					&all_pinned);
 		spin_unlock(&busiest->lock);
 
-		if (!nr_moved) {
+		if (unlikely(all_pinned)) {
 			cpu_clear(cpu_of(busiest), cpus);
 			if (!cpus_empty(cpus))
 				goto redo;