diff options
47 files changed, 928 insertions, 1170 deletions
diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt index 6d27ab8..c83bd6b 100644 --- a/Documentation/trace/kprobetrace.txt +++ b/Documentation/trace/kprobetrace.txt @@ -120,7 +120,6 @@ format: field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1;signed:0; field:int common_pid; offset:4; size:4; signed:1; - field:int common_lock_depth; offset:8; size:4; signed:1; field:unsigned long __probe_ip; offset:12; size:4; signed:0; field:int __probe_nargs; offset:16; size:4; signed:1; diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c index 42aa078..5a621c6 100644 --- a/arch/alpha/kernel/smp.c +++ b/arch/alpha/kernel/smp.c @@ -585,8 +585,7 @@ handle_ipi(struct pt_regs *regs) switch (which) { case IPI_RESCHEDULE: - /* Reschedule callback. Everything to be done - is done by the interrupt return path. */ + scheduler_ipi(); break; case IPI_CALL_FUNC: diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index f29b8a2..007a0a9 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -560,10 +560,7 @@ asmlinkage void __exception_irq_entry do_IPI(int ipinr, struct pt_regs *regs) break; case IPI_RESCHEDULE: - /* - * nothing more to do - eveything is - * done on the interrupt return path - */ + scheduler_ipi(); break; case IPI_CALL_FUNC: diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c index 8bce5ed..1fbd94c 100644 --- a/arch/blackfin/mach-common/smp.c +++ b/arch/blackfin/mach-common/smp.c @@ -177,6 +177,9 @@ static irqreturn_t ipi_handler_int1(int irq, void *dev_instance) while (msg_queue->count) { msg = &msg_queue->ipi_message[msg_queue->head]; switch (msg->type) { + case BFIN_IPI_RESCHEDULE: + scheduler_ipi(); + break; case BFIN_IPI_CALL_FUNC: spin_unlock_irqrestore(&msg_queue->lock, flags); ipi_call_function(cpu, msg); diff --git a/arch/cris/arch-v32/kernel/smp.c b/arch/cris/arch-v32/kernel/smp.c index 4c9e3e1..66cc756 100644 --- a/arch/cris/arch-v32/kernel/smp.c +++ b/arch/cris/arch-v32/kernel/smp.c @@ -342,15 +342,18 @@ irqreturn_t crisv32_ipi_interrupt(int irq, void *dev_id) ipi = REG_RD(intr_vect, irq_regs[smp_processor_id()], rw_ipi); + if (ipi.vector & IPI_SCHEDULE) { + scheduler_ipi(); + } if (ipi.vector & IPI_CALL) { - func(info); + func(info); } if (ipi.vector & IPI_FLUSH_TLB) { - if (flush_mm == FLUSH_ALL) - __flush_tlb_all(); - else if (flush_vma == FLUSH_ALL) + if (flush_mm == FLUSH_ALL) + __flush_tlb_all(); + else if (flush_vma == FLUSH_ALL) __flush_tlb_mm(flush_mm); - else + else __flush_tlb_page(flush_vma, flush_addr); } diff --git a/arch/ia64/kernel/irq_ia64.c b/arch/ia64/kernel/irq_ia64.c index 5b70474..782c3a35 100644 --- a/arch/ia64/kernel/irq_ia64.c +++ b/arch/ia64/kernel/irq_ia64.c @@ -31,6 +31,7 @@ #include <linux/irq.h> #include <linux/ratelimit.h> #include <linux/acpi.h> +#include <linux/sched.h> #include <asm/delay.h> #include <asm/intrinsics.h> @@ -496,6 +497,7 @@ ia64_handle_irq (ia64_vector vector, struct pt_regs *regs) smp_local_flush_tlb(); kstat_incr_irqs_this_cpu(irq, desc); } else if (unlikely(IS_RESCHEDULE(vector))) { + scheduler_ipi(); kstat_incr_irqs_this_cpu(irq, desc); } else { ia64_setreg(_IA64_REG_CR_TPR, vector); diff --git a/arch/ia64/xen/irq_xen.c b/arch/ia64/xen/irq_xen.c index 108bb85..b279e14 100644 --- a/arch/ia64/xen/irq_xen.c +++ b/arch/ia64/xen/irq_xen.c @@ -92,6 +92,8 @@ static unsigned short saved_irq_cnt; static int xen_slab_ready; #ifdef CONFIG_SMP +#include <linux/sched.h> + /* Dummy stub. Though we may check XEN_RESCHEDULE_VECTOR before __do_IRQ, * it ends up to issue several memory accesses upon percpu data and * thus adds unnecessary traffic to other paths. @@ -99,7 +101,13 @@ static int xen_slab_ready; static irqreturn_t xen_dummy_handler(int irq, void *dev_id) { + return IRQ_HANDLED; +} +static irqreturn_t +xen_resched_handler(int irq, void *dev_id) +{ + scheduler_ipi(); return IRQ_HANDLED; } @@ -110,7 +118,7 @@ static struct irqaction xen_ipi_irqaction = { }; static struct irqaction xen_resched_irqaction = { - .handler = xen_dummy_handler, + .handler = xen_resched_handler, .flags = IRQF_DISABLED, .name = "resched" }; diff --git a/arch/m32r/kernel/smp.c b/arch/m32r/kernel/smp.c index 31cef20..fc10b39 100644 --- a/arch/m32r/kernel/smp.c +++ b/arch/m32r/kernel/smp.c @@ -122,8 +122,6 @@ void smp_send_reschedule(int cpu_id) * * Description: This routine executes on CPU which received * 'RESCHEDULE_IPI'. - * Rescheduling is processed at the exit of interrupt - * operation. * * Born on Date: 2002.02.05 * @@ -138,7 +136,7 @@ void smp_send_reschedule(int cpu_id) *==========================================================================*/ void smp_reschedule_interrupt(void) { - /* nothing to do */ + scheduler_ipi(); } /*==========================================================================* diff --git a/arch/mips/cavium-octeon/smp.c b/arch/mips/cavium-octeon/smp.c index 716fae6..8b60642 100644 --- a/arch/mips/cavium-octeon/smp.c +++ b/arch/mips/cavium-octeon/smp.c @@ -44,6 +44,8 @@ static irqreturn_t mailbox_interrupt(int irq, void *dev_id) if (action & SMP_CALL_FUNCTION) smp_call_function_interrupt(); + if (action & SMP_RESCHEDULE_YOURSELF) + scheduler_ipi(); /* Check if we've been told to flush the icache */ if (action & SMP_ICACHE_FLUSH) diff --git a/arch/mips/kernel/smtc.c b/arch/mips/kernel/smtc.c index 5a88cc4..cedac46 100644 --- a/arch/mips/kernel/smtc.c +++ b/arch/mips/kernel/smtc.c @@ -929,7 +929,7 @@ static void post_direct_ipi(int cpu, struct smtc_ipi *pipi) static void ipi_resched_interrupt(void) { - /* Return from interrupt should be enough to cause scheduler check */ + scheduler_ipi(); } static void ipi_call_interrupt(void) diff --git a/arch/mips/mti-malta/malta-int.c b/arch/mips/mti-malta/malta-int.c index e85c977..1d36c511 100644 --- a/arch/mips/mti-malta/malta-int.c +++ b/arch/mips/mti-malta/malta-int.c @@ -308,6 +308,8 @@ static void ipi_call_dispatch(void) static irqreturn_t ipi_resched_interrupt(int irq, void *dev_id) { + scheduler_ipi(); + return IRQ_HANDLED; } diff --git a/arch/mips/pmc-sierra/yosemite/smp.c b/arch/mips/pmc-sierra/yosemite/smp.c index efc9e88..2608752 100644 --- a/arch/mips/pmc-sierra/yosemite/smp.c +++ b/arch/mips/pmc-sierra/yosemite/smp.c @@ -55,6 +55,8 @@ void titan_mailbox_irq(void) if (status & 0x2) smp_call_function_interrupt(); + if (status & 0x4) + scheduler_ipi(); break; case 1: @@ -63,6 +65,8 @@ void titan_mailbox_irq(void) if (status & 0x2) smp_call_function_interrupt(); + if (status & 0x4) + scheduler_ipi(); break; } } diff --git a/arch/mips/sgi-ip27/ip27-irq.c b/arch/mips/sgi-ip27/ip27-irq.c index 0a04603..b18b04e 100644 --- a/arch/mips/sgi-ip27/ip27-irq.c +++ b/arch/mips/sgi-ip27/ip27-irq.c @@ -147,8 +147,10 @@ static void ip27_do_irq_mask0(void) #ifdef CONFIG_SMP if (pend0 & (1UL << CPU_RESCHED_A_IRQ)) { LOCAL_HUB_CLR_INTR(CPU_RESCHED_A_IRQ); + scheduler_ipi(); } else if (pend0 & (1UL << CPU_RESCHED_B_IRQ)) { LOCAL_HUB_CLR_INTR(CPU_RESCHED_B_IRQ); + scheduler_ipi(); } else if (pend0 & (1UL << CPU_CALL_A_IRQ)) { LOCAL_HUB_CLR_INTR(CPU_CALL_A_IRQ); smp_call_function_interrupt(); diff --git a/arch/mips/sibyte/bcm1480/smp.c b/arch/mips/sibyte/bcm1480/smp.c index 47b347c..d667875 100644 --- a/arch/mips/sibyte/bcm1480/smp.c +++ b/arch/mips/sibyte/bcm1480/smp.c @@ -20,6 +20,7 @@ #include <linux/delay.h> #include <linux/smp.h> #include <linux/kernel_stat.h> +#include <linux/sched.h> #include <asm/mmu_context.h> #include <asm/io.h> @@ -189,10 +190,8 @@ void bcm1480_mailbox_interrupt(void) /* Clear the mailbox to clear the interrupt */ __raw_writeq(((u64)action)<<48, mailbox_0_clear_regs[cpu]); - /* - * Nothing to do for SMP_RESCHEDULE_YOURSELF; returning from the - * interrupt will do the reschedule for us - */ + if (action & SMP_RESCHEDULE_YOURSELF) + scheduler_ipi(); if (action & SMP_CALL_FUNCTION) smp_call_function_interrupt(); diff --git a/arch/mips/sibyte/sb1250/smp.c b/arch/mips/sibyte/sb1250/smp.c index c00a5cb..38e7f6b 100644 --- a/arch/mips/sibyte/sb1250/smp.c +++ b/arch/mips/sibyte/sb1250/smp.c @@ -21,6 +21,7 @@ #include <linux/interrupt.h> #include <linux/smp.h> #include <linux/kernel_stat.h> +#include <linux/sched.h> #include <asm/mmu_context.h> #include <asm/io.h> @@ -177,10 +178,8 @@ void sb1250_mailbox_interrupt(void) /* Clear the mailbox to clear the interrupt */ ____raw_writeq(((u64)action) << 48, mailbox_clear_regs[cpu]); - /* - * Nothing to do for SMP_RESCHEDULE_YOURSELF; returning from the - * interrupt will do the reschedule for us - */ + if (action & SMP_RESCHEDULE_YOURSELF) + scheduler_ipi(); if (action & SMP_CALL_FUNCTION) smp_call_function_interrupt(); diff --git a/arch/mn10300/kernel/smp.c b/arch/mn10300/kernel/smp.c index 226c826..83fb279 100644 --- a/arch/mn10300/kernel/smp.c +++ b/arch/mn10300/kernel/smp.c @@ -494,14 +494,11 @@ void smp_send_stop(void) * @irq: The interrupt number. * @dev_id: The device ID. * - * We need do nothing here, since the scheduling will be effected on our way - * back through entry.S. - * * Returns IRQ_HANDLED to indicate we handled the interrupt successfully. */ static irqreturn_t smp_reschedule_interrupt(int irq, void *dev_id) { - /* do nothing */ + scheduler_ipi(); return IRQ_HANDLED; } diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c index 69d63d3..828305f 100644 --- a/arch/parisc/kernel/smp.c +++ b/arch/parisc/kernel/smp.c @@ -155,10 +155,7 @@ ipi_interrupt(int irq, void *dev_id) case IPI_RESCHEDULE: smp_debug(100, KERN_DEBUG "CPU%d IPI_RESCHEDULE\n", this_cpu); - /* - * Reschedule callback. Everything to be - * done is done by the interrupt return path. - */ + scheduler_ipi(); break; case IPI_CALL_FUNC: diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index cbdbb14..9f9c204 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -116,7 +116,7 @@ void smp_message_recv(int msg) generic_smp_call_function_interrupt(); break; case PPC_MSG_RESCHEDULE: - /* we notice need_resched on exit */ + scheduler_ipi(); break; case PPC_MSG_CALL_FUNC_SINGLE: generic_smp_call_function_single_interrupt(); @@ -146,7 +146,7 @@ static irqreturn_t call_function_action(int irq, void *data) static irqreturn_t reschedule_action(int irq, void *data) { - /* we just need the return path side effect of checking need_resched */ + scheduler_ipi(); return IRQ_HANDLED; } diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 63a97db..63c7d9f 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -165,12 +165,12 @@ static void do_ext_call_interrupt(unsigned int ext_int_code, kstat_cpu(smp_processor_id()).irqs[EXTINT_IPI]++; /* * handle bit signal external calls - * - * For the ec_schedule signal we have to do nothing. All the work - * is done automatically when we return from the interrupt. */ bits = xchg(&S390_lowcore.ext_call_fast, 0); + if (test_bit(ec_schedule, &bits)) + scheduler_ipi(); + if (test_bit(ec_call_function, &bits)) generic_smp_call_function_interrupt(); diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index 509b36b..6207561 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -20,6 +20,7 @@ #include <linux/module.h> #include <linux/cpu.h> #include <linux/interrupt.h> +#include <linux/sched.h> #include <asm/atomic.h> #include <asm/processor.h> #include <asm/system.h> @@ -323,6 +324,7 @@ void smp_message_recv(unsigned int msg) generic_smp_call_function_interrupt(); break; case SMP_MSG_RESCHEDULE: + scheduler_ipi(); break; case SMP_MSG_FUNCTION_SINGLE: generic_smp_call_function_single_interrupt(); diff --git a/arch/sparc/include/asm/topology_64.h b/arch/sparc/include/asm/topology_64.h index 1c79f32..8b9c556 100644 --- a/arch/sparc/include/asm/topology_64.h +++ b/arch/sparc/include/asm/topology_64.h @@ -65,6 +65,10 @@ static inline int pcibus_to_node(struct pci_bus *pbus) #define smt_capable() (sparc64_multi_core) #endif /* CONFIG_SMP */ -#define cpu_coregroup_mask(cpu) (&cpu_core_map[cpu]) +extern cpumask_t cpu_core_map[NR_CPUS]; +static inline const struct cpumask *cpu_coregroup_mask(int cpu) +{ + return &cpu_core_map[cpu]; +} #endif /* _ASM_SPARC64_TOPOLOGY_H */ diff --git a/arch/sparc/kernel/smp_32.c b/arch/sparc/kernel/smp_32.c index 850a136..442286d 100644 --- a/arch/sparc/kernel/smp_32.c +++ b/arch/sparc/kernel/smp_32.c @@ -129,7 +129,9 @@ struct linux_prom_registers smp_penguin_ctable __cpuinitdata = { 0 }; void smp_send_reschedule(int cpu) { - /* See sparc64 */ + /* + * XXX missing reschedule IPI, see scheduler_ipi() + */ } void smp_send_stop(void) diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c index 3e94a8c..9478da7 100644 --- a/arch/sparc/kernel/smp_64.c +++ b/arch/sparc/kernel/smp_64.c @@ -1368,6 +1368,7 @@ void smp_send_reschedule(int cpu) void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs) { clear_softint(1 << irq); + scheduler_ipi(); } /* This is a nop because we capture all other cpus diff --git a/arch/tile/kernel/smp.c b/arch/tile/kernel/smp.c index a429310..c52224d 100644 --- a/arch/tile/kernel/smp.c +++ b/arch/tile/kernel/smp.c @@ -189,12 +189,8 @@ void flush_icache_range(unsigned long start, unsigned long end) /* Called when smp_send_reschedule() triggers IRQ_RESCHEDULE. */ static irqreturn_t handle_reschedule_ipi(int irq, void *token) { - /* - * Nothing to do here; when we return from interrupt, the - * rescheduling will occur there. But do bump the interrupt - * profiler count in the meantime. - */ __get_cpu_var(irq_stat).irq_resched_count++; + scheduler_ipi(); return IRQ_HANDLED; } diff --git a/arch/um/kernel/smp.c b/arch/um/kernel/smp.c index 106bf27..eefb107 100644 --- a/arch/um/kernel/smp.c +++ b/arch/um/kernel/smp.c @@ -173,7 +173,7 @@ void IPI_handler(int cpu) break; case 'R': - set_tsk_need_resched(current); + scheduler_ipi(); break; case 'S': diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c index 513deac..013e7eb 100644 --- a/arch/x86/kernel/smp.c +++ b/arch/x86/kernel/smp.c @@ -194,14 +194,13 @@ static void native_stop_other_cpus(int wait) } /* - * Reschedule call back. Nothing to do, - * all the work is done automatically when - * we return from the interrupt. + * Reschedule call back. */ void smp_reschedule_interrupt(struct pt_regs *regs) { ack_APIC_irq(); inc_irq_stat(irq_resched_count); + scheduler_ipi(); /* * KVM uses this interrupt to force a cpu out of guest mode */ diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 194a3ed..41038c0 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -46,13 +46,12 @@ static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id); static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id); /* - * Reschedule call back. Nothing to do, - * all the work is done automatically when - * we return from the interrupt. + * Reschedule call back. */ static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id) { inc_irq_stat(irq_resched_count); + scheduler_ipi(); return IRQ_HANDLED; } diff --git a/include/linux/init_task.h b/include/linux/init_task.h index caa151f..689496b 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -134,7 +134,6 @@ extern struct cred init_cred; .stack = &init_thread_info, \ .usage = ATOMIC_INIT(2), \ .flags = PF_KTHREAD, \ - .lock_depth = -1, \ .prio = MAX_PRIO-20, \ .static_prio = MAX_PRIO-20, \ .normal_prio = MAX_PRIO-20, \ diff --git a/include/linux/mutex.h b/include/linux/mutex.h index 94b48bd..c75471d 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -51,7 +51,7 @@ struct mutex { spinlock_t wait_lock; struct list_head wait_list; #if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_SMP) - struct thread_info *owner; + struct task_struct *owner; #endif #ifdef CONFIG_DEBUG_MUTEXES const char *name; diff --git a/include/linux/sched.h b/include/linux/sched.h index 781abd1..12211e1 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -360,7 +360,7 @@ extern signed long schedule_timeout_interruptible(signed long timeout); extern signed long schedule_timeout_killable(signed long timeout); extern signed long schedule_timeout_uninterruptible(signed long timeout); asmlinkage void schedule(void); -extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner); +extern int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner); struct nsproxy; struct user_namespace; @@ -731,10 +731,6 @@ struct sched_info { /* timestamps */ unsigned long long last_arrival,/* when we last ran on a cpu */ last_queued; /* when we were last queued to run */ -#ifdef CONFIG_SCHEDSTATS - /* BKL stats */ - unsigned int bkl_count; -#endif }; #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ @@ -868,6 +864,7 @@ static inline int sd_power_saving_flags(void) struct sched_group { struct sched_group *next; /* Must be a circular list */ + atomic_t ref; /* * CPU power of this group, SCHED_LOAD_SCALE being max power for a @@ -882,9 +879,6 @@ struct sched_group { * NOTE: this field is variable length. (Allocated dynamically * by attaching extra space to the end of the structure, * depending on how many CPUs the kernel has booted up with) - * - * It is also be embedded into static data structures at build - * time. (See 'struct static_sched_group' in kernel/sched.c) */ unsigned long cpumask[0]; }; @@ -894,17 +888,6 @@ static inline struct cpumask *sched_group_cpus(struct sched_group *sg) return to_cpumask(sg->cpumask); } -enum sched_domain_level { - SD_LV_NONE = 0, - SD_LV_SIBLING, - SD_LV_MC, - SD_LV_BOOK, - SD_LV_CPU, - SD_LV_NODE, - SD_LV_ALLNODES, - SD_LV_MAX -}; - struct sched_domain_attr { int relax_domain_level; }; @@ -913,6 +896,8 @@ struct sched_domain_attr { .relax_domain_level = -1, \ } +extern int sched_domain_level_max; + struct sched_domain { /* These fields must be setup */ struct sched_domain *parent; /* top domain must be null terminated */ @@ -930,7 +915,7 @@ struct sched_domain { unsigned int forkexec_idx; unsigned int smt_gain; int flags; /* See SD_* */ - enum sched_domain_level level; + int level; /* Runtime fields. */ unsigned long last_balance; /* init to jiffies. units in jiffies */ @@ -973,6 +958,10 @@ struct sched_domain { #ifdef CONFIG_SCHED_DEBUG char *name; #endif + union { + void *private; /* used during construction */ + struct rcu_head rcu; /* used during destruction */ + }; unsigned int span_weight; /* @@ -981,9 +970,6 @@ struct sched_domain { * NOTE: this field is variable length. (Allocated dynamically * by attaching extra space to the end of the structure, * depending on how many CPUs the kernel has booted up with) - * - * It is also be embedded into static data structures at build - * time. (See 'struct static_sched_domain' in kernel/sched.c) */ unsigned long span[0]; }; @@ -1048,8 +1034,12 @@ struct sched_domain; #define WF_FORK 0x02 /* child wakeup after fork */ #define ENQUEUE_WAKEUP 1 -#define ENQUEUE_WAKING 2 -#define ENQUEUE_HEAD 4 +#define ENQUEUE_HEAD 2 +#ifdef CONFIG_SMP +#define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */ +#else +#define ENQUEUE_WAKING 0 +#endif #define DEQUEUE_SLEEP 1 @@ -1067,12 +1057,11 @@ struct sched_class { void (*put_prev_task) (struct rq *rq, struct task_struct *p); #ifdef CONFIG_SMP - int (*select_task_rq)(struct rq *rq, struct task_struct *p, - int sd_flag, int flags); + int (*select_task_rq)(struct task_struct *p, int sd_flag, int flags); void (*pre_schedule) (struct rq *this_rq, struct task_struct *task); void (*post_schedule) (struct rq *this_rq); - void (*task_waking) (struct rq *this_rq, struct task_struct *task); + void (*task_waking) (struct task_struct *task); void (*task_woken) (struct rq *this_rq, struct task_struct *task); void (*set_cpus_allowed)(struct task_struct *p, @@ -1197,13 +1186,11 @@ struct task_struct { unsigned int flags; /* per process flags, defined below */ unsigned int ptrace; - int lock_depth; /* BKL lock depth */ - #ifdef CONFIG_SMP -#ifdef __ARCH_WANT_UNLOCKED_CTXSW - int oncpu; -#endif + struct task_struct *wake_entry; + int on_cpu; #endif + int on_rq; int prio, static_prio, normal_prio; unsigned int rt_priority; @@ -1274,6 +1261,7 @@ struct task_struct { /* Revert to default priority/policy when forking */ unsigned sched_reset_on_fork:1; + unsigned sched_contributes_to_load:1; pid_t pid; pid_t tgid; @@ -2063,14 +2051,13 @@ extern void xtime_update(unsigned long ticks); extern int wake_up_state(struct task_struct *tsk, unsigned int state); extern int wake_up_process(struct task_struct *tsk); -extern void wake_up_new_task(struct task_struct *tsk, - unsigned long clone_flags); +extern void wake_up_new_task(struct task_struct *tsk); #ifdef CONFIG_SMP extern void kick_process(struct task_struct *tsk); #else static inline void kick_process(struct task_struct *tsk) { } #endif -extern void sched_fork(struct task_struct *p, int clone_flags); +extern void sched_fork(struct task_struct *p); extern void sched_dead(struct task_struct *p); extern void proc_caches_init(void); @@ -2195,8 +2182,10 @@ extern void set_task_comm(struct task_struct *tsk, char *from); extern char *get_task_comm(char *to, struct task_struct *tsk); #ifdef CONFIG_SMP +void scheduler_ipi(void); extern unsigned long wait_task_inactive(struct task_struct *, long match_state); #else +static inline void scheduler_ipi(void) { } static inline unsigned long wait_task_inactive(struct task_struct *p, long match_state) { diff --git a/init/Kconfig b/init/Kconfig index 7a71e0a..af958ad 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -827,6 +827,11 @@ config SCHED_AUTOGROUP desktop applications. Task group autogeneration is currently based upon task session. +config SCHED_TTWU_QUEUE + bool + depends on !SPARC32 + default y + config MM_OWNER bool diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 33eee16..2bb8c2e 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1159,7 +1159,7 @@ int current_cpuset_is_being_rebound(void) static int update_relax_domain_level(struct cpuset *cs, s64 val) { #ifdef CONFIG_SMP - if (val < -1 || val >= SD_LV_MAX) + if (val < -1 || val >= sched_domain_level_max) return -EINVAL; #endif diff --git a/kernel/fork.c b/kernel/fork.c index e7548de..2b44d82 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1103,7 +1103,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, posix_cpu_timers_init(p); - p->lock_depth = -1; /* -1 = no lock */ do_posix_clock_monotonic_gettime(&p->start_time); p->real_start_time = p->start_time; monotonic_to_bootbased(&p->real_start_time); @@ -1153,7 +1152,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, #endif /* Perform scheduler related setup. Assign this task to a CPU. */ - sched_fork(p, clone_flags); + sched_fork(p); retval = perf_event_init_task(p); if (retval) @@ -1464,7 +1463,7 @@ long do_fork(unsigned long clone_flags, */ p->flags &= ~PF_STARTING; - wake_up_new_task(p, clone_flags); + wake_up_new_task(p); tracehook_report_clone_complete(trace, regs, clone_flags, nr, p); diff --git a/kernel/mutex-debug.c b/kernel/mutex-debug.c index ec815a9..73da83a 100644 --- a/kernel/mutex-debug.c +++ b/kernel/mutex-debug.c @@ -75,7 +75,7 @@ void debug_mutex_unlock(struct mutex *lock) return; DEBUG_LOCKS_WARN_ON(lock->magic != lock); - DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info()); + DEBUG_LOCKS_WARN_ON(lock->owner != current); DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next); mutex_clear_owner(lock); } diff --git a/kernel/mutex-debug.h b/kernel/mutex-debug.h index 57d527a..0799fd3 100644 --- a/kernel/mutex-debug.h +++ b/kernel/mutex-debug.h @@ -29,7 +29,7 @@ extern void debug_mutex_init(struct mutex *lock, const char *name, static inline void mutex_set_owner(struct mutex *lock) { - lock->owner = current_thread_info(); + lock->owner = current; } static inline void mutex_clear_owner(struct mutex *lock) diff --git a/kernel/mutex.c b/kernel/mutex.c index c4195fa..2c938e2 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -160,14 +160,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, */ for (;;) { - struct thread_info *owner; - - /* - * If we own the BKL, then don't spin. The owner of - * the mutex might be waiting on us to release the BKL. - */ - if (unlikely(current->lock_depth >= 0)) - break; + struct task_struct *owner; /* * If there's an owner, wait for it to either diff --git a/kernel/mutex.h b/kernel/mutex.h index 67578ca..4115fbf 100644 --- a/kernel/mutex.h +++ b/kernel/mutex.h @@ -19,7 +19,7 @@ #ifdef CONFIG_SMP static inline void mutex_set_owner(struct mutex *lock) { - lock->owner = current_thread_info(); + lock->owner = current; } static inline void mutex_clear_owner(struct mutex *lock) diff --git a/kernel/sched.c b/kernel/sched.c index 312f8b9..c62acf4 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -231,7 +231,7 @@ static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b) #endif /* - * sched_domains_mutex serializes calls to arch_init_sched_domains, + * sched_domains_mutex serializes calls to init_sched_domains, * detach_destroy_domains and partition_sched_domains. */ static DEFINE_MUTEX(sched_domains_mutex); @@ -312,6 +312,9 @@ struct cfs_rq { u64 exec_clock; u64 min_vruntime; +#ifndef CONFIG_64BIT + u64 min_vruntime_copy; +#endif struct rb_root tasks_timeline; struct rb_node *rb_leftmost; @@ -325,7 +328,9 @@ struct cfs_rq { */ struct sched_entity *curr, *next, *last, *skip; +#ifdef CONFIG_SCHED_DEBUG unsigned int nr_spread_over; +#endif #ifdef CONFIG_FAIR_GROUP_SCHED struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */ @@ -417,6 +422,7 @@ struct rt_rq { */ struct root_domain { atomic_t refcount; + struct rcu_head rcu; cpumask_var_t span; cpumask_var_t online; @@ -460,7 +466,7 @@ struct rq { u64 nohz_stamp; unsigned char nohz_balance_kick; #endif - unsigned int skip_clock_update; + int skip_clock_update; /* capture load from *all* tasks on this cpu: */ struct load_weight load; @@ -553,6 +559,10 @@ struct rq { unsigned int ttwu_count; unsigned int ttwu_local; #endif + +#ifdef CONFIG_SMP + struct task_struct *wake_list; +#endif }; static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); @@ -571,7 +581,7 @@ static inline int cpu_of(struct rq *rq) #define rcu_dereference_check_sched_domain(p) \ rcu_dereference_check((p), \ - rcu_read_lock_sched_held() || \ + rcu_read_lock_held() || \ lockdep_is_held(&sched_domains_mutex)) /* @@ -596,7 +606,7 @@ static inline int cpu_of(struct rq *rq) * Return the group to which this tasks belongs. * * We use task_subsys_state_check() and extend the RCU verification - * with lockdep_is_held(&task_rq(p)->lock) because cpu_cgroup_attach() + * with lockdep_is_held(&p->pi_lock) because cpu_cgroup_attach() * holds that lock for each task it moves into the cgroup. Therefore * by holding that lock, we pin the task to the current cgroup. */ @@ -606,7 +616,7 @@ static inline struct task_group *task_group(struct task_struct *p) struct cgroup_subsys_state *css; css = task_subsys_state_check(p, cpu_cgroup_subsys_id, - lockdep_is_held(&task_rq(p)->lock)); + lockdep_is_held(&p->pi_lock)); tg = container_of(css, struct task_group, css); return autogroup_task_group(p, tg); @@ -642,7 +652,7 @@ static void update_rq_clock(struct rq *rq) { s64 delta; - if (rq->skip_clock_update) + if (rq->skip_clock_update > 0) return; delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; @@ -838,18 +848,39 @@ static inline int task_current(struct rq *rq, struct task_struct *p) return rq->curr == p; } -#ifndef __ARCH_WANT_UNLOCKED_CTXSW static inline int task_running(struct rq *rq, struct task_struct *p) { +#ifdef CONFIG_SMP + return p->on_cpu; +#else return task_current(rq, p); +#endif } +#ifndef __ARCH_WANT_UNLOCKED_CTXSW static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) { +#ifdef CONFIG_SMP + /* + * We can optimise this out completely for !SMP, because the + * SMP rebalancing from interrupt is the only thing that cares + * here. + */ + next->on_cpu = 1; +#endif } static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) { +#ifdef CONFIG_SMP + /* + * After ->on_cpu is cleared, the task can be moved to a different CPU. + * We must ensure this doesn't happen until the switch is completely + * finished. + */ + smp_wmb(); + prev->on_cpu = 0; +#endif #ifdef CONFIG_DEBUG_SPINLOCK /* this is a valid case when another task releases the spinlock */ rq->lock.owner = current; @@ -865,15 +896,6 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) } #else /* __ARCH_WANT_UNLOCKED_CTXSW */ -static inline int task_running(struct rq *rq, struct task_struct *p) -{ -#ifdef CONFIG_SMP - return p->oncpu; -#else - return task_current(rq, p); -#endif -} - static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) { #ifdef CONFIG_SMP @@ -882,7 +904,7 @@ static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) * SMP rebalancing from interrupt is the only thing that cares * here. */ - next->oncpu = 1; + next->on_cpu = 1; #endif #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW raw_spin_unlock_irq(&rq->lock); @@ -895,12 +917,12 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) { #ifdef CONFIG_SMP /* - * After ->oncpu is cleared, the task can be moved to a different CPU. + * After ->on_cpu is cleared, the task can be moved to a different CPU. * We must ensure this doesn't happen until the switch is completely * finished. */ smp_wmb(); - prev->oncpu = 0; + prev->on_cpu = 0; #endif #ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW local_irq_enable(); @@ -909,23 +931,15 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) #endif /* __ARCH_WANT_UNLOCKED_CTXSW */ /* - * Check whether the task is waking, we use this to synchronize ->cpus_allowed - * against ttwu(). - */ -static inline int task_is_waking(struct task_struct *p) -{ - return unlikely(p->state == TASK_WAKING); -} - -/* - * __task_rq_lock - lock the runqueue a given task resides on. - * Must be called interrupts disabled. + * __task_rq_lock - lock the rq @p resides on. */ static inline struct rq *__task_rq_lock(struct task_struct *p) __acquires(rq->lock) { struct rq *rq; + lockdep_assert_held(&p->pi_lock); + for (;;) { rq = task_rq(p); raw_spin_lock(&rq->lock); @@ -936,22 +950,22 @@ static inline struct rq *__task_rq_lock(struct task_struct *p) } /* - * task_rq_lock - lock the runqueue a given task resides on and disable - * interrupts. Note the ordering: we can safely lookup the task_rq without - * explicitly disabling preemption. + * task_rq_lock - lock p->pi_lock and lock the rq @p resides on. */ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags) + __acquires(p->pi_lock) __acquires(rq->lock) { struct rq *rq; for (;;) { - local_irq_save(*flags); + raw_spin_lock_irqsave(&p->pi_lock, *flags); rq = task_rq(p); raw_spin_lock(&rq->lock); if (likely(rq == task_rq(p))) return rq; - raw_spin_unlock_irqrestore(&rq->lock, *flags); + raw_spin_unlock(&rq->lock); + raw_spin_unlock_irqrestore(&p->pi_lock, *flags); } } @@ -961,10 +975,13 @@ static void __task_rq_unlock(struct rq *rq) raw_spin_unlock(&rq->lock); } -static inline void task_rq_unlock(struct rq *rq, unsigned long *flags) +static inline void +task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags) __releases(rq->lock) + __releases(p->pi_lock) { - raw_spin_unlock_irqrestore(&rq->lock, *flags); + raw_spin_unlock(&rq->lock); + raw_spin_unlock_irqrestore(&p->pi_lock, *flags); } /* @@ -1193,11 +1210,17 @@ int get_nohz_timer_target(void) int i; struct sched_domain *sd; + rcu_read_lock(); for_each_domain(cpu, sd) { - for_each_cpu(i, sched_domain_span(sd)) - if (!idle_cpu(i)) - return i; + for_each_cpu(i, sched_domain_span(sd)) { + if (!idle_cpu(i)) { + cpu = i; + goto unlock; + } + } } +unlock: + rcu_read_unlock(); return cpu; } /* @@ -1307,15 +1330,15 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight, { u64 tmp; + tmp = (u64)delta_exec * weight; + if (!lw->inv_weight) { if (BITS_PER_LONG > 32 && unlikely(lw->weight >= WMULT_CONST)) lw->inv_weight = 1; else - lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2) - / (lw->weight+1); + lw->inv_weight = WMULT_CONST / lw->weight; } - tmp = (u64)delta_exec * weight; /* * Check whether we'd overflow the 64-bit multiplication: */ @@ -1773,7 +1796,6 @@ static void enqueue_task(struct rq *rq, struct task_struct *p, int flags) update_rq_clock(rq); sched_info_queued(p); p->sched_class->enqueue_task(rq, p, flags); - p->se.on_rq = 1; } static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) @@ -1781,7 +1803,6 @@ static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) update_rq_clock(rq); sched_info_dequeued(p); p->sched_class->dequeue_task(rq, p, flags); - p->se.on_rq = 0; } /* @@ -2116,7 +2137,7 @@ static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) * A queue event has occurred, and we're going to schedule. In * this case, we can save a useless back to back clock update. */ - if (rq->curr->se.on_rq && test_tsk_need_resched(rq->curr)) + if (rq->curr->on_rq && test_tsk_need_resched(rq->curr)) rq->skip_clock_update = 1; } @@ -2162,6 +2183,11 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) */ WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING && !(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE)); + +#ifdef CONFIG_LOCKDEP + WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) || + lockdep_is_held(&task_rq(p)->lock))); +#endif #endif trace_sched_migrate_task(p, new_cpu); @@ -2182,19 +2208,6 @@ struct migration_arg { static int migration_cpu_stop(void *data); /* - * The task's runqueue lock must be held. - * Returns true if you have to wait for migration thread. - */ -static bool migrate_task(struct task_struct *p, struct rq *rq) -{ - /* - * If the task is not on a runqueue (and not running), then - * the next wake-up will properly place the task. - */ - return p->se.on_rq || task_running(rq, p); -} - -/* * wait_task_inactive - wait for a thread to unschedule. * * If @match_state is nonzero, it's the @p->state value just checked and @@ -2251,11 +2264,11 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) rq = task_rq_lock(p, &flags); trace_sched_wait_task(p); running = task_running(rq, p); - on_rq = p->se.on_rq; + on_rq = p->on_rq; ncsw = 0; if (!match_state || p->state == match_state) ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); /* * If it changed from the expected state, bail out now. @@ -2330,7 +2343,7 @@ EXPORT_SYMBOL_GPL(kick_process); #ifdef CONFIG_SMP /* - * ->cpus_allowed is protected by either TASK_WAKING or rq->lock held. + * ->cpus_allowed is protected by both rq->lock and p->pi_lock */ static int select_fallback_rq(int cpu, struct task_struct *p) { @@ -2363,12 +2376,12 @@ static int select_fallback_rq(int cpu, struct task_struct *p) } /* - * The caller (fork, wakeup) owns TASK_WAKING, ->cpus_allowed is stable. + * The caller (fork, wakeup) owns p->pi_lock, ->cpus_allowed is stable. */ static inline -int select_task_rq(struct rq *rq, struct task_struct *p, int sd_flags, int wake_flags) +int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags) { - int cpu = p->sched_class->select_task_rq(rq, p, sd_flags, wake_flags); + int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags); /* * In order not to call set_task_cpu() on a blocking task we need @@ -2394,27 +2407,62 @@ static void update_avg(u64 *avg, u64 sample) } #endif -static inline void ttwu_activate(struct task_struct *p, struct rq *rq, - bool is_sync, bool is_migrate, bool is_local, - unsigned long en_flags) +static void +ttwu_stat(struct task_struct *p, int cpu, int wake_flags) { +#ifdef CONFIG_SCHEDSTATS + struct rq *rq = this_rq(); + +#ifdef CONFIG_SMP + int this_cpu = smp_processor_id(); + + if (cpu == this_cpu) { + schedstat_inc(rq, ttwu_local); + schedstat_inc(p, se.statistics.nr_wakeups_local); + } else { + struct sched_domain *sd; + + schedstat_inc(p, se.statistics.nr_wakeups_remote); + rcu_read_lock(); + for_each_domain(this_cpu, sd) { + if (cpumask_test_cpu(cpu, sched_domain_span(sd))) { + schedstat_inc(sd, ttwu_wake_remote); + break; + } + } + rcu_read_unlock(); + } +#endif /* CONFIG_SMP */ + + schedstat_inc(rq, ttwu_count); schedstat_inc(p, se.statistics.nr_wakeups); - if (is_sync) + + if (wake_flags & WF_SYNC) schedstat_inc(p, se.statistics.nr_wakeups_sync); - if (is_migrate) + + if (cpu != task_cpu(p)) schedstat_inc(p, se.statistics.nr_wakeups_migrate); - if (is_local) - schedstat_inc(p, se.statistics.nr_wakeups_local); - else - schedstat_inc(p, se.statistics.nr_wakeups_remote); +#endif /* CONFIG_SCHEDSTATS */ +} + +static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags) +{ activate_task(rq, p, en_flags); + p->on_rq = 1; + + /* if a worker is waking up, notify workqueue */ + if (p->flags & PF_WQ_WORKER) + wq_worker_waking_up(p, cpu_of(rq)); } -static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, - int wake_flags, bool success) +/* + * Mark the task runnable and perform wakeup-preemption. + */ +static void +ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) { - trace_sched_wakeup(p, success); + trace_sched_wakeup(p, true); check_preempt_curr(rq, p, wake_flags); p->state = TASK_RUNNING; @@ -2433,9 +2481,99 @@ static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, rq->idle_stamp = 0; } #endif - /* if a worker is waking up, notify workqueue */ - if ((p->flags & PF_WQ_WORKER) && success) - wq_worker_waking_up(p, cpu_of(rq)); +} + +static void +ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags) +{ +#ifdef CONFIG_SMP + if (p->sched_contributes_to_load) + rq->nr_uninterruptible--; +#endif + + ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING); + ttwu_do_wakeup(rq, p, wake_flags); +} + +/* + * Called in case the task @p isn't fully descheduled from its runqueue, + * in this case we must do a remote wakeup. Its a 'light' wakeup though, + * since all we need to do is flip p->state to TASK_RUNNING, since + * the task is still ->on_rq. + */ +static int ttwu_remote(struct task_struct *p, int wake_flags) +{ + struct rq *rq; + int ret = 0; + + rq = __task_rq_lock(p); + if (p->on_rq) { + ttwu_do_wakeup(rq, p, wake_flags); + ret = 1; + } + __task_rq_unlock(rq); + + return ret; +} + +#ifdef CONFIG_SMP +static void sched_ttwu_pending(void) +{ + struct rq *rq = this_rq(); + struct task_struct *list = xchg(&rq->wake_list, NULL); + + if (!list) + return; + + raw_spin_lock(&rq->lock); + + while (list) { + struct task_struct *p = list; + list = list->wake_entry; + ttwu_do_activate(rq, p, 0); + } + + raw_spin_unlock(&rq->lock); +} + +void scheduler_ipi(void) +{ + sched_ttwu_pending(); +} + +static void ttwu_queue_remote(struct task_struct *p, int cpu) +{ + struct rq *rq = cpu_rq(cpu); + struct task_struct *next = rq->wake_list; + + for (;;) { + struct task_struct *old = next; + + p->wake_entry = next; + next = cmpxchg(&rq->wake_list, old, p); + if (next == old) + break; + } + + if (!next) + smp_send_reschedule(cpu); +} +#endif + +static void ttwu_queue(struct task_struct *p, int cpu) +{ + struct rq *rq = cpu_rq(cpu); + +#if defined(CONFIG_SMP) && defined(CONFIG_SCHED_TTWU_QUEUE) + if (sched_feat(TTWU_QUEUE) && cpu != smp_processor_id()) { + ttwu_queue_remote(p, cpu); + return; + } +#endif + + raw_spin_lock(&rq->lock); + ttwu_do_activate(rq, p, 0); + raw_spin_unlock(&rq->lock); } /** @@ -2453,92 +2591,64 @@ static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, * Returns %true if @p was woken up, %false if it was already running * or @state didn't match @p's state. */ -static int try_to_wake_up(struct task_struct *p, unsigned int state, - int wake_flags) +static int +try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) { - int cpu, orig_cpu, this_cpu, success = 0; unsigned long flags; - unsigned long en_flags = ENQUEUE_WAKEUP; - struct rq *rq; - - this_cpu = get_cpu(); + int cpu, success = 0; smp_wmb(); - rq = task_rq_lock(p, &flags); + raw_spin_lock_irqsave(&p->pi_lock, flags); if (!(p->state & state)) goto out; - if (p->se.on_rq) - goto out_running; - + success = 1; /* we're going to change ->state */ cpu = task_cpu(p); - orig_cpu = cpu; -#ifdef CONFIG_SMP - if (unlikely(task_running(rq, p))) - goto out_activate; + if (p->on_rq && ttwu_remote(p, wake_flags)) + goto stat; +#ifdef CONFIG_SMP /* - * In order to handle concurrent wakeups and release the rq->lock - * we put the task in TASK_WAKING state. - * - * First fix up the nr_uninterruptible count: + * If the owning (remote) cpu is still in the middle of schedule() with + * this task as prev, wait until its done referencing the task. */ - if (task_contributes_to_load(p)) { - if (likely(cpu_online(orig_cpu))) - rq->nr_uninterruptible--; - else - this_rq()->nr_uninterruptible--; - } - p->state = TASK_WAKING; - - if (p->sched_class->task_waking) { - p->sched_class->task_waking(rq, p); - en_flags |= ENQUEUE_WAKING; + while (p->on_cpu) { +#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW + /* + * If called from interrupt context we could have landed in the + * middle of schedule(), in this case we should take care not + * to spin on ->on_cpu if p is current, since that would + * deadlock. + */ + if (p == current) { + ttwu_queue(p, cpu); + goto stat; + } +#endif + cpu_relax(); } - - cpu = select_task_rq(rq, p, SD_BALANCE_WAKE, wake_flags); - if (cpu != orig_cpu) - set_task_cpu(p, cpu); - __task_rq_unlock(rq); - - rq = cpu_rq(cpu); - raw_spin_lock(&rq->lock); - /* - * We migrated the task without holding either rq->lock, however - * since the task is not on the task list itself, nobody else - * will try and migrate the task, hence the rq should match the - * cpu we just moved it to. + * Pairs with the smp_wmb() in finish_lock_switch(). */ - WARN_ON(task_cpu(p) != cpu); - WARN_ON(p->state != TASK_WAKING); + smp_rmb(); -#ifdef CONFIG_SCHEDSTATS - schedstat_inc(rq, ttwu_count); - if (cpu == this_cpu) - schedstat_inc(rq, ttwu_local); - else { - struct sched_domain *sd; - for_each_domain(this_cpu, sd) { - if (cpumask_test_cpu(cpu, sched_domain_span(sd))) { - schedstat_inc(sd, ttwu_wake_remote); - break; - } - } - } -#endif /* CONFIG_SCHEDSTATS */ + p->sched_contributes_to_load = !!task_contributes_to_load(p); + p->state = TASK_WAKING; + + if (p->sched_class->task_waking) + p->sched_class->task_waking(p); -out_activate: + cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags); + if (task_cpu(p) != cpu) + set_task_cpu(p, cpu); #endif /* CONFIG_SMP */ - ttwu_activate(p, rq, wake_flags & WF_SYNC, orig_cpu != cpu, - cpu == this_cpu, en_flags); - success = 1; -out_running: - ttwu_post_activation(p, rq, wake_flags, success); + + ttwu_queue(p, cpu); +stat: + ttwu_stat(p, cpu, wake_flags); out: - task_rq_unlock(rq, &flags); - put_cpu(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); return success; } @@ -2547,31 +2657,34 @@ out: * try_to_wake_up_local - try to wake up a local task with rq lock held * @p: the thread to be awakened * - * Put @p on the run-queue if it's not already there. The caller must + * Put @p on the run-queue if it's not already there. The caller must * ensure that this_rq() is locked, @p is bound to this_rq() and not - * the current task. this_rq() stays locked over invocation. + * the current task. */ static void try_to_wake_up_local(struct task_struct *p) { struct rq *rq = task_rq(p); - bool success = false; BUG_ON(rq != this_rq()); BUG_ON(p == current); lockdep_assert_held(&rq->lock); + if (!raw_spin_trylock(&p->pi_lock)) { + raw_spin_unlock(&rq->lock); + raw_spin_lock(&p->pi_lock); + raw_spin_lock(&rq->lock); + } + if (!(p->state & TASK_NORMAL)) - return; + goto out; - if (!p->se.on_rq) { - if (likely(!task_running(rq, p))) { - schedstat_inc(rq, ttwu_count); - schedstat_inc(rq, ttwu_local); - } - ttwu_activate(p, rq, false, false, true, ENQUEUE_WAKEUP); - success = true; - } - ttwu_post_activation(p, rq, 0, success); + if (!p->on_rq) + ttwu_activate(rq, p, ENQUEUE_WAKEUP); + + ttwu_do_wakeup(rq, p, 0); + ttwu_stat(p, smp_processor_id(), 0); +out: + raw_spin_unlock(&p->pi_lock); } /** @@ -2604,19 +2717,21 @@ int wake_up_state(struct task_struct *p, unsigned int state) */ static void __sched_fork(struct task_struct *p) { + p->on_rq = 0; + + p->se.on_rq = 0; p->se.exec_start = 0; p->se.sum_exec_runtime = 0; p->se.prev_sum_exec_runtime = 0; p->se.nr_migrations = 0; p->se.vruntime = 0; + INIT_LIST_HEAD(&p->se.group_node); #ifdef CONFIG_SCHEDSTATS memset(&p->se.statistics, 0, sizeof(p->se.statistics)); #endif INIT_LIST_HEAD(&p->rt.run_list); - p->se.on_rq = 0; - INIT_LIST_HEAD(&p->se.group_node); #ifdef CONFIG_PREEMPT_NOTIFIERS INIT_HLIST_HEAD(&p->preempt_notifiers); @@ -2626,8 +2741,9 @@ static void __sched_fork(struct task_struct *p) /* * fork()/clone()-time setup: */ -void sched_fork(struct task_struct *p, int clone_flags) +void sched_fork(struct task_struct *p) { + unsigned long flags; int cpu = get_cpu(); __sched_fork(p); @@ -2678,16 +2794,16 @@ void sched_fork(struct task_struct *p, int clone_flags) * * Silence PROVE_RCU. */ - rcu_read_lock(); + raw_spin_lock_irqsave(&p->pi_lock, flags); set_task_cpu(p, cpu); - rcu_read_unlock(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) if (likely(sched_info_on())) memset(&p->sched_info, 0, sizeof(p->sched_info)); #endif -#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW) - p->oncpu = 0; +#if defined(CONFIG_SMP) + p->on_cpu = 0; #endif #ifdef CONFIG_PREEMPT /* Want to start with kernel preemption disabled. */ @@ -2707,41 +2823,31 @@ void sched_fork(struct task_struct *p, int clone_flags) * that must be done for every newly created context, then puts the task * on the runqueue and wakes it. */ -void wake_up_new_task(struct task_struct *p, unsigned long clone_flags) +void wake_up_new_task(struct task_struct *p) { unsigned long flags; struct rq *rq; - int cpu __maybe_unused = get_cpu(); + raw_spin_lock_irqsave(&p->pi_lock, flags); #ifdef CONFIG_SMP - rq = task_rq_lock(p, &flags); - p->state = TASK_WAKING; - /* * Fork balancing, do it here and not earlier because: * - cpus_allowed can change in the fork path * - any previously selected cpu might disappear through hotplug - * - * We set TASK_WAKING so that select_task_rq() can drop rq->lock - * without people poking at ->cpus_allowed. */ - cpu = select_task_rq(rq, p, SD_BALANCE_FORK, 0); - set_task_cpu(p, cpu); - - p->state = TASK_RUNNING; - task_rq_unlock(rq, &flags); + set_task_cpu(p, select_task_rq(p, SD_BALANCE_FORK, 0)); #endif - rq = task_rq_lock(p, &flags); + rq = __task_rq_lock(p); activate_task(rq, p, 0); - trace_sched_wakeup_new(p, 1); + p->on_rq = 1; + trace_sched_wakeup_new(p, true); check_preempt_curr(rq, p, WF_FORK); #ifdef CONFIG_SMP if (p->sched_class->task_woken) p->sched_class->task_woken(rq, p); #endif - task_rq_unlock(rq, &flags); - put_cpu(); + task_rq_unlock(rq, p, &flags); } #ifdef CONFIG_PREEMPT_NOTIFIERS @@ -3450,27 +3556,22 @@ void sched_exec(void) { struct task_struct *p = current; unsigned long flags; - struct rq *rq; int dest_cpu; - rq = task_rq_lock(p, &flags); - dest_cpu = p->sched_class->select_task_rq(rq, p, SD_BALANCE_EXEC, 0); + raw_spin_lock_irqsave(&p->pi_lock, flags); + dest_cpu = p->sched_class->select_task_rq(p, SD_BALANCE_EXEC, 0); if (dest_cpu == smp_processor_id()) goto unlock; - /* - * select_task_rq() can race against ->cpus_allowed - */ - if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed) && - likely(cpu_active(dest_cpu)) && migrate_task(p, rq)) { + if (likely(cpu_active(dest_cpu))) { struct migration_arg arg = { p, dest_cpu }; - task_rq_unlock(rq, &flags); - stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg); return; } unlock: - task_rq_unlock(rq, &flags); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); } #endif @@ -3507,7 +3608,7 @@ unsigned long long task_delta_exec(struct task_struct *p) rq = task_rq_lock(p, &flags); ns = do_task_delta_exec(p, rq); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ns; } @@ -3525,7 +3626,7 @@ unsigned long long task_sched_runtime(struct task_struct *p) rq = task_rq_lock(p, &flags); ns = p->se.sum_exec_runtime + do_task_delta_exec(p, rq); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ns; } @@ -3549,7 +3650,7 @@ unsigned long long thread_group_sched_runtime(struct task_struct *p) rq = task_rq_lock(p, &flags); thread_group_cputime(p, &totals); ns = totals.sum_exec_runtime + do_task_delta_exec(p, rq); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ns; } @@ -3903,9 +4004,6 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) /* * This function gets called by the timer code, with HZ frequency. * We call it with interrupts disabled. - * - * It also gets called by the fork code, when changing the parent's - * timeslices. */ void scheduler_tick(void) { @@ -4025,17 +4123,11 @@ static inline void schedule_debug(struct task_struct *prev) profile_hit(SCHED_PROFILING, __builtin_return_address(0)); schedstat_inc(this_rq(), sched_count); -#ifdef CONFIG_SCHEDSTATS - if (unlikely(prev->lock_depth >= 0)) { - schedstat_inc(this_rq(), rq_sched_info.bkl_count); - schedstat_inc(prev, sched_info.bkl_count); - } -#endif } static void put_prev_task(struct rq *rq, struct task_struct *prev) { - if (prev->se.on_rq) + if (prev->on_rq || rq->skip_clock_update < 0) update_rq_clock(rq); prev->sched_class->put_prev_task(rq, prev); } @@ -4097,11 +4189,13 @@ need_resched: if (unlikely(signal_pending_state(prev->state, prev))) { prev->state = TASK_RUNNING; } else { + deactivate_task(rq, prev, DEQUEUE_SLEEP); + prev->on_rq = 0; + /* - * If a worker is going to sleep, notify and - * ask workqueue whether it wants to wake up a - * task to maintain concurrency. If so, wake - * up the task. + * If a worker went to sleep, notify and ask workqueue + * whether it wants to wake up a task to maintain + * concurrency. */ if (prev->flags & PF_WQ_WORKER) { struct task_struct *to_wakeup; @@ -4110,11 +4204,10 @@ need_resched: if (to_wakeup) try_to_wake_up_local(to_wakeup); } - deactivate_task(rq, prev, DEQUEUE_SLEEP); /* - * If we are going to sleep and we have plugged IO queued, make - * sure to submit it to avoid deadlocks. + * If we are going to sleep and we have plugged IO + * queued, make sure to submit it to avoid deadlocks. */ if (blk_needs_flush_plug(prev)) { raw_spin_unlock(&rq->lock); @@ -4161,70 +4254,53 @@ need_resched: EXPORT_SYMBOL(schedule); #ifdef CONFIG_MUTEX_SPIN_ON_OWNER -/* - * Look out! "owner" is an entirely speculative pointer - * access and not reliable. - */ -int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner) -{ - unsigned int cpu; - struct rq *rq; - if (!sched_feat(OWNER_SPIN)) - return 0; +static inline bool owner_running(struct mutex *lock, struct task_struct *owner) +{ + bool ret = false; -#ifdef CONFIG_DEBUG_PAGEALLOC - /* - * Need to access the cpu field knowing that - * DEBUG_PAGEALLOC could have unmapped it if - * the mutex owner just released it and exited. - */ - if (probe_kernel_address(&owner->cpu, cpu)) - return 0; -#else - cpu = owner->cpu; -#endif + rcu_read_lock(); + if (lock->owner != owner) + goto fail; /* - * Even if the access succeeded (likely case), - * the cpu field may no longer be valid. + * Ensure we emit the owner->on_cpu, dereference _after_ checking + * lock->owner still matches owner, if that fails, owner might + * point to free()d memory, if it still matches, the rcu_read_lock() + * ensures the memory stays valid. */ - if (cpu >= nr_cpumask_bits) - return 0; + barrier(); - /* - * We need to validate that we can do a - * get_cpu() and that we have the percpu area. - */ - if (!cpu_online(cpu)) - return 0; + ret = owner->on_cpu; +fail: + rcu_read_unlock(); - rq = cpu_rq(cpu); + return ret; +} - for (;;) { - /* - * Owner changed, break to re-assess state. - */ - if (lock->owner != owner) { - /* - * If the lock has switched to a different owner, - * we likely have heavy contention. Return 0 to quit - * optimistic spinning and not contend further: - */ - if (lock->owner) - return 0; - break; - } +/* + * Look out! "owner" is an entirely speculative pointer + * access and not reliable. + */ +int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner) +{ + if (!sched_feat(OWNER_SPIN)) + return 0; - /* - * Is that owner really running on that cpu? - */ - if (task_thread_info(rq->curr) != owner || need_resched()) + while (owner_running(lock, owner)) { + if (need_resched()) return 0; arch_mutex_cpu_relax(); } + /* + * If the owner changed to another task there is likely + * heavy contention, stop spinning. + */ + if (lock->owner) + return 0; + return 1; } #endif @@ -4684,19 +4760,18 @@ EXPORT_SYMBOL(sleep_on_timeout); */ void rt_mutex_setprio(struct task_struct *p, int prio) { - unsigned long flags; int oldprio, on_rq, running; struct rq *rq; const struct sched_class *prev_class; BUG_ON(prio < 0 || prio > MAX_PRIO); - rq = task_rq_lock(p, &flags); + rq = __task_rq_lock(p); trace_sched_pi_setprio(p, prio); oldprio = p->prio; prev_class = p->sched_class; - on_rq = p->se.on_rq; + on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) dequeue_task(rq, p, 0); @@ -4716,7 +4791,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0); check_class_changed(rq, p, prev_class, oldprio); - task_rq_unlock(rq, &flags); + __task_rq_unlock(rq); } #endif @@ -4744,7 +4819,7 @@ void set_user_nice(struct task_struct *p, long nice) p->static_prio = NICE_TO_PRIO(nice); goto out_unlock; } - on_rq = p->se.on_rq; + on_rq = p->on_rq; if (on_rq) dequeue_task(rq, p, 0); @@ -4764,7 +4839,7 @@ void set_user_nice(struct task_struct *p, long nice) resched_task(rq->curr); } out_unlock: - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); } EXPORT_SYMBOL(set_user_nice); @@ -4878,8 +4953,6 @@ static struct task_struct *find_process_by_pid(pid_t pid) static void __setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) { - BUG_ON(p->se.on_rq); - p->policy = policy; p->rt_priority = prio; p->normal_prio = normal_prio(p); @@ -4994,20 +5067,17 @@ recheck: /* * make sure no PI-waiters arrive (or leave) while we are * changing the priority of the task: - */ - raw_spin_lock_irqsave(&p->pi_lock, flags); - /* + * * To be able to change p->policy safely, the appropriate * runqueue lock must be held. */ - rq = __task_rq_lock(p); + rq = task_rq_lock(p, &flags); /* * Changing the policy of the stop threads its a very bad idea */ if (p == rq->stop) { - __task_rq_unlock(rq); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + task_rq_unlock(rq, p, &flags); return -EINVAL; } @@ -5031,8 +5101,7 @@ recheck: if (rt_bandwidth_enabled() && rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0 && !task_group_is_autogroup(task_group(p))) { - __task_rq_unlock(rq); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + task_rq_unlock(rq, p, &flags); return -EPERM; } } @@ -5041,11 +5110,10 @@ recheck: /* recheck policy now with rq lock held */ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { policy = oldpolicy = -1; - __task_rq_unlock(rq); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + task_rq_unlock(rq, p, &flags); goto recheck; } - on_rq = p->se.on_rq; + on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) deactivate_task(rq, p, 0); @@ -5064,8 +5132,7 @@ recheck: activate_task(rq, p, 0); check_class_changed(rq, p, prev_class, oldprio); - __task_rq_unlock(rq); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + task_rq_unlock(rq, p, &flags); rt_mutex_adjust_pi(p); @@ -5316,7 +5383,6 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask) { struct task_struct *p; unsigned long flags; - struct rq *rq; int retval; get_online_cpus(); @@ -5331,9 +5397,9 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask) if (retval) goto out_unlock; - rq = task_rq_lock(p, &flags); + raw_spin_lock_irqsave(&p->pi_lock, flags); cpumask_and(mask, &p->cpus_allowed, cpu_online_mask); - task_rq_unlock(rq, &flags); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); out_unlock: rcu_read_unlock(); @@ -5658,7 +5724,7 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, rq = task_rq_lock(p, &flags); time_slice = p->sched_class->get_rr_interval(rq, p); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); rcu_read_unlock(); jiffies_to_timespec(time_slice, &t); @@ -5776,17 +5842,14 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) rcu_read_unlock(); rq->curr = rq->idle = idle; -#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW) - idle->oncpu = 1; +#if defined(CONFIG_SMP) + idle->on_cpu = 1; #endif raw_spin_unlock_irqrestore(&rq->lock, flags); /* Set the preempt count _outside_ the spinlocks! */ -#if defined(CONFIG_PREEMPT) - task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0); -#else task_thread_info(idle)->preempt_count = 0; -#endif + /* * The idle tasks have their own, simple scheduling class: */ @@ -5881,26 +5944,17 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) unsigned int dest_cpu; int ret = 0; - /* - * Serialize against TASK_WAKING so that ttwu() and wunt() can - * drop the rq->lock and still rely on ->cpus_allowed. - */ -again: - while (task_is_waking(p)) - cpu_relax(); rq = task_rq_lock(p, &flags); - if (task_is_waking(p)) { - task_rq_unlock(rq, &flags); - goto again; - } + + if (cpumask_equal(&p->cpus_allowed, new_mask)) + goto out; if (!cpumask_intersects(new_mask, cpu_active_mask)) { ret = -EINVAL; goto out; } - if (unlikely((p->flags & PF_THREAD_BOUND) && p != current && - !cpumask_equal(&p->cpus_allowed, new_mask))) { + if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) { ret = -EINVAL; goto out; } @@ -5917,16 +5971,16 @@ again: goto out; dest_cpu = cpumask_any_and(cpu_active_mask, new_mask); - if (migrate_task(p, rq)) { + if (p->on_rq) { struct migration_arg arg = { p, dest_cpu }; /* Need help from migration thread: drop lock and wait. */ - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); tlb_migrate_finish(p->mm); return 0; } out: - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ret; } @@ -5954,6 +6008,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) rq_src = cpu_rq(src_cpu); rq_dest = cpu_rq(dest_cpu); + raw_spin_lock(&p->pi_lock); double_rq_lock(rq_src, rq_dest); /* Already moved. */ if (task_cpu(p) != src_cpu) @@ -5966,7 +6021,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) * If we're not on a rq, the next wake-up will ensure we're * placed properly. */ - if (p->se.on_rq) { + if (p->on_rq) { deactivate_task(rq_src, p, 0); set_task_cpu(p, dest_cpu); activate_task(rq_dest, p, 0); @@ -5976,6 +6031,7 @@ done: ret = 1; fail: double_rq_unlock(rq_src, rq_dest); + raw_spin_unlock(&p->pi_lock); return ret; } @@ -6316,6 +6372,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) #ifdef CONFIG_HOTPLUG_CPU case CPU_DYING: + sched_ttwu_pending(); /* Update our root-domain */ raw_spin_lock_irqsave(&rq->lock, flags); if (rq->rd) { @@ -6394,6 +6451,8 @@ early_initcall(migration_init); #ifdef CONFIG_SMP +static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */ + #ifdef CONFIG_SCHED_DEBUG static __read_mostly int sched_domain_debug_enabled; @@ -6489,7 +6548,6 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, static void sched_domain_debug(struct sched_domain *sd, int cpu) { - cpumask_var_t groupmask; int level = 0; if (!sched_domain_debug_enabled) @@ -6502,20 +6560,14 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu) printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu); - if (!alloc_cpumask_var(&groupmask, GFP_KERNEL)) { - printk(KERN_DEBUG "Cannot load-balance (out of memory)\n"); - return; - } - for (;;) { - if (sched_domain_debug_one(sd, cpu, level, groupmask)) + if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask)) break; level++; sd = sd->parent; if (!sd) break; } - free_cpumask_var(groupmask); } #else /* !CONFIG_SCHED_DEBUG */ # define sched_domain_debug(sd, cpu) do { } while (0) @@ -6572,12 +6624,11 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) return 1; } -static void free_rootdomain(struct root_domain *rd) +static void free_rootdomain(struct rcu_head *rcu) { - synchronize_sched(); + struct root_domain *rd = container_of(rcu, struct root_domain, rcu); cpupri_cleanup(&rd->cpupri); - free_cpumask_var(rd->rto_mask); free_cpumask_var(rd->online); free_cpumask_var(rd->span); @@ -6618,7 +6669,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd) raw_spin_unlock_irqrestore(&rq->lock, flags); if (old_rd) - free_rootdomain(old_rd); + call_rcu_sched(&old_rd->rcu, free_rootdomain); } static int init_rootdomain(struct root_domain *rd) @@ -6669,6 +6720,25 @@ static struct root_domain *alloc_rootdomain(void) return rd; } +static void free_sched_domain(struct rcu_head *rcu) +{ + struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu); + if (atomic_dec_and_test(&sd->groups->ref)) + kfree(sd->groups); + kfree(sd); +} + +static void destroy_sched_domain(struct sched_domain *sd, int cpu) +{ + call_rcu(&sd->rcu, free_sched_domain); +} + +static void destroy_sched_domains(struct sched_domain *sd, int cpu) +{ + for (; sd; sd = sd->parent) + destroy_sched_domain(sd, cpu); +} + /* * Attach the domain 'sd' to 'cpu' as its base domain. Callers must * hold the hotplug lock. @@ -6679,9 +6749,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) struct rq *rq = cpu_rq(cpu); struct sched_domain *tmp; - for (tmp = sd; tmp; tmp = tmp->parent) - tmp->span_weight = cpumask_weight(sched_domain_span(tmp)); - /* Remove the sched domains which do not contribute to scheduling. */ for (tmp = sd; tmp; ) { struct sched_domain *parent = tmp->parent; @@ -6692,12 +6759,15 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) tmp->parent = parent->parent; if (parent->parent) parent->parent->child = tmp; + destroy_sched_domain(parent, cpu); } else tmp = tmp->parent; } if (sd && sd_degenerate(sd)) { + tmp = sd; sd = sd->parent; + destroy_sched_domain(tmp, cpu); if (sd) sd->child = NULL; } @@ -6705,7 +6775,9 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) sched_domain_debug(sd, cpu); rq_attach_root(rq, rd); + tmp = rq->sd; rcu_assign_pointer(rq->sd, sd); + destroy_sched_domains(tmp, cpu); } /* cpus with isolated domains */ @@ -6721,56 +6793,6 @@ static int __init isolated_cpu_setup(char *str) __setup("isolcpus=", isolated_cpu_setup); -/* - * init_sched_build_groups takes the cpumask we wish to span, and a pointer - * to a function which identifies what group(along with sched group) a CPU - * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids - * (due to the fact that we keep track of groups covered with a struct cpumask). - * - * init_sched_build_groups will build a circular linked list of the groups - * covered by the given span, and will set each group's ->cpumask correctly, - * and ->cpu_power to 0. - */ -static void -init_sched_build_groups(const struct cpumask *span, - const struct cpumask *cpu_map, - int (*group_fn)(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, - struct cpumask *tmpmask), - struct cpumask *covered, struct cpumask *tmpmask) -{ - struct sched_group *first = NULL, *last = NULL; - int i; - - cpumask_clear(covered); - - for_each_cpu(i, span) { - struct sched_group *sg; - int group = group_fn(i, cpu_map, &sg, tmpmask); - int j; - - if (cpumask_test_cpu(i, covered)) - continue; - - cpumask_clear(sched_group_cpus(sg)); - sg->cpu_power = 0; - - for_each_cpu(j, span) { - if (group_fn(j, cpu_map, NULL, tmpmask) != group) - continue; - - cpumask_set_cpu(j, covered); - cpumask_set_cpu(j, sched_group_cpus(sg)); - } - if (!first) - first = sg; - if (last) - last->next = sg; - last = sg; - } - last->next = first; -} - #define SD_NODES_PER_DOMAIN 16 #ifdef CONFIG_NUMA @@ -6787,7 +6809,7 @@ init_sched_build_groups(const struct cpumask *span, */ static int find_next_best_node(int node, nodemask_t *used_nodes) { - int i, n, val, min_val, best_node = 0; + int i, n, val, min_val, best_node = -1; min_val = INT_MAX; @@ -6811,7 +6833,8 @@ static int find_next_best_node(int node, nodemask_t *used_nodes) } } - node_set(best_node, *used_nodes); + if (best_node != -1) + node_set(best_node, *used_nodes); return best_node; } @@ -6837,315 +6860,130 @@ static void sched_domain_node_span(int node, struct cpumask *span) for (i = 1; i < SD_NODES_PER_DOMAIN; i++) { int next_node = find_next_best_node(node, &used_nodes); - + if (next_node < 0) + break; cpumask_or(span, span, cpumask_of_node(next_node)); } } + +static const struct cpumask *cpu_node_mask(int cpu) +{ + lockdep_assert_held(&sched_domains_mutex); + + sched_domain_node_span(cpu_to_node(cpu), sched_domains_tmpmask); + + return sched_domains_tmpmask; +} + +static const struct cpumask *cpu_allnodes_mask(int cpu) +{ + return cpu_possible_mask; +} #endif /* CONFIG_NUMA */ -int sched_smt_power_savings = 0, sched_mc_power_savings = 0; +static const struct cpumask *cpu_cpu_mask(int cpu) +{ + return cpumask_of_node(cpu_to_node(cpu)); +} -/* - * The cpus mask in sched_group and sched_domain hangs off the end. - * - * ( See the the comments in include/linux/sched.h:struct sched_group - * and struct sched_domain. ) - */ -struct static_sched_group { - struct sched_group sg; - DECLARE_BITMAP(cpus, CONFIG_NR_CPUS); -}; +int sched_smt_power_savings = 0, sched_mc_power_savings = 0; -struct static_sched_domain { - struct sched_domain sd; - DECLARE_BITMAP(span, CONFIG_NR_CPUS); +struct sd_data { + struct sched_domain **__percpu sd; + struct sched_group **__percpu sg; }; struct s_data { -#ifdef CONFIG_NUMA - int sd_allnodes; - cpumask_var_t domainspan; - cpumask_var_t covered; - cpumask_var_t notcovered; -#endif - cpumask_var_t nodemask; - cpumask_var_t this_sibling_map; - cpumask_var_t this_core_map; - cpumask_var_t this_book_map; - cpumask_var_t send_covered; - cpumask_var_t tmpmask; - struct sched_group **sched_group_nodes; + struct sched_domain ** __percpu sd; struct root_domain *rd; }; enum s_alloc { - sa_sched_groups = 0, sa_rootdomain, - sa_tmpmask, - sa_send_covered, - sa_this_book_map, - sa_this_core_map, - sa_this_sibling_map, - sa_nodemask, - sa_sched_group_nodes, -#ifdef CONFIG_NUMA - sa_notcovered, - sa_covered, - sa_domainspan, -#endif + sa_sd, + sa_sd_storage, sa_none, }; -/* - * SMT sched-domains: - */ -#ifdef CONFIG_SCHED_SMT -static DEFINE_PER_CPU(struct static_sched_domain, cpu_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_groups); +struct sched_domain_topology_level; -static int -cpu_to_cpu_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *unused) -{ - if (sg) - *sg = &per_cpu(sched_groups, cpu).sg; - return cpu; -} -#endif /* CONFIG_SCHED_SMT */ +typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu); +typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); -/* - * multi-core sched-domains: - */ -#ifdef CONFIG_SCHED_MC -static DEFINE_PER_CPU(struct static_sched_domain, core_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_core); - -static int -cpu_to_core_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *mask) -{ - int group; -#ifdef CONFIG_SCHED_SMT - cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map); - group = cpumask_first(mask); -#else - group = cpu; -#endif - if (sg) - *sg = &per_cpu(sched_group_core, group).sg; - return group; -} -#endif /* CONFIG_SCHED_MC */ +struct sched_domain_topology_level { + sched_domain_init_f init; + sched_domain_mask_f mask; + struct sd_data data; +}; /* - * book sched-domains: + * Assumes the sched_domain tree is fully constructed */ -#ifdef CONFIG_SCHED_BOOK -static DEFINE_PER_CPU(struct static_sched_domain, book_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_book); - -static int -cpu_to_book_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *mask) +static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg) { - int group = cpu; -#ifdef CONFIG_SCHED_MC - cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map); - group = cpumask_first(mask); -#elif defined(CONFIG_SCHED_SMT) - cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map); - group = cpumask_first(mask); -#endif - if (sg) - *sg = &per_cpu(sched_group_book, group).sg; - return group; -} -#endif /* CONFIG_SCHED_BOOK */ + struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu); + struct sched_domain *child = sd->child; -static DEFINE_PER_CPU(struct static_sched_domain, phys_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_phys); + if (child) + cpu = cpumask_first(sched_domain_span(child)); -static int -cpu_to_phys_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *mask) -{ - int group; -#ifdef CONFIG_SCHED_BOOK - cpumask_and(mask, cpu_book_mask(cpu), cpu_map); - group = cpumask_first(mask); -#elif defined(CONFIG_SCHED_MC) - cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map); - group = cpumask_first(mask); -#elif defined(CONFIG_SCHED_SMT) - cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map); - group = cpumask_first(mask); -#else - group = cpu; -#endif if (sg) - *sg = &per_cpu(sched_group_phys, group).sg; - return group; + *sg = *per_cpu_ptr(sdd->sg, cpu); + + return cpu; } -#ifdef CONFIG_NUMA /* - * The init_sched_build_groups can't handle what we want to do with node - * groups, so roll our own. Now each node has its own list of groups which - * gets dynamically allocated. + * build_sched_groups takes the cpumask we wish to span, and a pointer + * to a function which identifies what group(along with sched group) a CPU + * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids + * (due to the fact that we keep track of groups covered with a struct cpumask). + * + * build_sched_groups will build a circular linked list of the groups + * covered by the given span, and will set each group's ->cpumask correctly, + * and ->cpu_power to 0. */ -static DEFINE_PER_CPU(struct static_sched_domain, node_domains); -static struct sched_group ***sched_group_nodes_bycpu; - -static DEFINE_PER_CPU(struct static_sched_domain, allnodes_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_allnodes); - -static int cpu_to_allnodes_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, - struct cpumask *nodemask) -{ - int group; - - cpumask_and(nodemask, cpumask_of_node(cpu_to_node(cpu)), cpu_map); - group = cpumask_first(nodemask); - - if (sg) - *sg = &per_cpu(sched_group_allnodes, group).sg; - return group; -} - -static void init_numa_sched_groups_power(struct sched_group *group_head) -{ - struct sched_group *sg = group_head; - int j; - - if (!sg) - return; - do { - for_each_cpu(j, sched_group_cpus(sg)) { - struct sched_domain *sd; - - sd = &per_cpu(phys_domains, j).sd; - if (j != group_first_cpu(sd->groups)) { - /* - * Only add "power" once for each - * physical package. - */ - continue; - } - - sg->cpu_power += sd->groups->cpu_power; - } - sg = sg->next; - } while (sg != group_head); -} - -static int build_numa_sched_groups(struct s_data *d, - const struct cpumask *cpu_map, int num) +static void +build_sched_groups(struct sched_domain *sd) { - struct sched_domain *sd; - struct sched_group *sg, *prev; - int n, j; - - cpumask_clear(d->covered); - cpumask_and(d->nodemask, cpumask_of_node(num), cpu_map); - if (cpumask_empty(d->nodemask)) { - d->sched_group_nodes[num] = NULL; - goto out; - } - - sched_domain_node_span(num, d->domainspan); - cpumask_and(d->domainspan, d->domainspan, cpu_map); - - sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(), - GFP_KERNEL, num); - if (!sg) { - printk(KERN_WARNING "Can not alloc domain group for node %d\n", - num); - return -ENOMEM; - } - d->sched_group_nodes[num] = sg; - - for_each_cpu(j, d->nodemask) { - sd = &per_cpu(node_domains, j).sd; - sd->groups = sg; - } - - sg->cpu_power = 0; - cpumask_copy(sched_group_cpus(sg), d->nodemask); - sg->next = sg; - cpumask_or(d->covered, d->covered, d->nodemask); + struct sched_group *first = NULL, *last = NULL; + struct sd_data *sdd = sd->private; + const struct cpumask *span = sched_domain_span(sd); + struct cpumask *covered; + int i; - prev = sg; - for (j = 0; j < nr_node_ids; j++) { - n = (num + j) % nr_node_ids; - cpumask_complement(d->notcovered, d->covered); - cpumask_and(d->tmpmask, d->notcovered, cpu_map); - cpumask_and(d->tmpmask, d->tmpmask, d->domainspan); - if (cpumask_empty(d->tmpmask)) - break; - cpumask_and(d->tmpmask, d->tmpmask, cpumask_of_node(n)); - if (cpumask_empty(d->tmpmask)) - continue; - sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(), - GFP_KERNEL, num); - if (!sg) { - printk(KERN_WARNING - "Can not alloc domain group for node %d\n", j); - return -ENOMEM; - } - sg->cpu_power = 0; - cpumask_copy(sched_group_cpus(sg), d->tmpmask); - sg->next = prev->next; - cpumask_or(d->covered, d->covered, d->tmpmask); - prev->next = sg; - prev = sg; - } -out: - return 0; -} -#endif /* CONFIG_NUMA */ + lockdep_assert_held(&sched_domains_mutex); + covered = sched_domains_tmpmask; -#ifdef CONFIG_NUMA -/* Free memory allocated for various sched_group structures */ -static void free_sched_groups(const struct cpumask *cpu_map, - struct cpumask *nodemask) -{ - int cpu, i; + cpumask_clear(covered); - for_each_cpu(cpu, cpu_map) { - struct sched_group **sched_group_nodes - = sched_group_nodes_bycpu[cpu]; + for_each_cpu(i, span) { + struct sched_group *sg; + int group = get_group(i, sdd, &sg); + int j; - if (!sched_group_nodes) + if (cpumask_test_cpu(i, covered)) continue; - for (i = 0; i < nr_node_ids; i++) { - struct sched_group *oldsg, *sg = sched_group_nodes[i]; + cpumask_clear(sched_group_cpus(sg)); + sg->cpu_power = 0; - cpumask_and(nodemask, cpumask_of_node(i), cpu_map); - if (cpumask_empty(nodemask)) + for_each_cpu(j, span) { + if (get_group(j, sdd, NULL) != group) continue; - if (sg == NULL) - continue; - sg = sg->next; -next_sg: - oldsg = sg; - sg = sg->next; - kfree(oldsg); - if (oldsg != sched_group_nodes[i]) - goto next_sg; + cpumask_set_cpu(j, covered); + cpumask_set_cpu(j, sched_group_cpus(sg)); } - kfree(sched_group_nodes); - sched_group_nodes_bycpu[cpu] = NULL; + + if (!first) + first = sg; + if (last) + last->next = sg; + last = sg; } + last->next = first; } -#else /* !CONFIG_NUMA */ -static void free_sched_groups(const struct cpumask *cpu_map, - struct cpumask *nodemask) -{ -} -#endif /* CONFIG_NUMA */ /* * Initialize sched groups cpu_power. @@ -7159,11 +6997,6 @@ static void free_sched_groups(const struct cpumask *cpu_map, */ static void init_sched_groups_power(int cpu, struct sched_domain *sd) { - struct sched_domain *child; - struct sched_group *group; - long power; - int weight; - WARN_ON(!sd || !sd->groups); if (cpu != group_first_cpu(sd->groups)) @@ -7171,36 +7004,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) sd->groups->group_weight = cpumask_weight(sched_group_cpus(sd->groups)); - child = sd->child; - - sd->groups->cpu_power = 0; - - if (!child) { - power = SCHED_LOAD_SCALE; - weight = cpumask_weight(sched_domain_span(sd)); - /* - * SMT siblings share the power of a single core. - * Usually multiple threads get a better yield out of - * that one core than a single thread would have, - * reflect that in sd->smt_gain. - */ - if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) { - power *= sd->smt_gain; - power /= weight; - power >>= SCHED_LOAD_SHIFT; - } - sd->groups->cpu_power += power; - return; - } - - /* - * Add cpu_power of each child group to this groups cpu_power. - */ - group = child->groups; - do { - sd->groups->cpu_power += group->cpu_power; - group = group->next; - } while (group != child->groups); + update_group_power(sd, cpu); } /* @@ -7214,15 +7018,15 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) # define SD_INIT_NAME(sd, type) do { } while (0) #endif -#define SD_INIT(sd, type) sd_init_##type(sd) - -#define SD_INIT_FUNC(type) \ -static noinline void sd_init_##type(struct sched_domain *sd) \ -{ \ - memset(sd, 0, sizeof(*sd)); \ - *sd = SD_##type##_INIT; \ - sd->level = SD_LV_##type; \ - SD_INIT_NAME(sd, type); \ +#define SD_INIT_FUNC(type) \ +static noinline struct sched_domain * \ +sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \ +{ \ + struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \ + *sd = SD_##type##_INIT; \ + SD_INIT_NAME(sd, type); \ + sd->private = &tl->data; \ + return sd; \ } SD_INIT_FUNC(CPU) @@ -7241,13 +7045,14 @@ SD_INIT_FUNC(CPU) #endif static int default_relax_domain_level = -1; +int sched_domain_level_max; static int __init setup_relax_domain_level(char *str) { unsigned long val; val = simple_strtoul(str, NULL, 0); - if (val < SD_LV_MAX) + if (val < sched_domain_level_max) default_relax_domain_level = val; return 1; @@ -7275,37 +7080,20 @@ static void set_domain_attribute(struct sched_domain *sd, } } +static void __sdt_free(const struct cpumask *cpu_map); +static int __sdt_alloc(const struct cpumask *cpu_map); + static void __free_domain_allocs(struct s_data *d, enum s_alloc what, const struct cpumask *cpu_map) { switch (what) { - case sa_sched_groups: - free_sched_groups(cpu_map, d->tmpmask); /* fall through */ - d->sched_group_nodes = NULL; case sa_rootdomain: - free_rootdomain(d->rd); /* fall through */ - case sa_tmpmask: - free_cpumask_var(d->tmpmask); /* fall through */ - case sa_send_covered: - free_cpumask_var(d->send_covered); /* fall through */ - case sa_this_book_map: - free_cpumask_var(d->this_book_map); /* fall through */ - case sa_this_core_map: - free_cpumask_var(d->this_core_map); /* fall through */ - case sa_this_sibling_map: - free_cpumask_var(d->this_sibling_map); /* fall through */ - case sa_nodemask: - free_cpumask_var(d->nodemask); /* fall through */ - case sa_sched_group_nodes: -#ifdef CONFIG_NUMA - kfree(d->sched_group_nodes); /* fall through */ - case sa_notcovered: - free_cpumask_var(d->notcovered); /* fall through */ - case sa_covered: - free_cpumask_var(d->covered); /* fall through */ - case sa_domainspan: - free_cpumask_var(d->domainspan); /* fall through */ -#endif + if (!atomic_read(&d->rd->refcount)) + free_rootdomain(&d->rd->rcu); /* fall through */ + case sa_sd: + free_percpu(d->sd); /* fall through */ + case sa_sd_storage: + __sdt_free(cpu_map); /* fall through */ case sa_none: break; } @@ -7314,308 +7102,212 @@ static void __free_domain_allocs(struct s_data *d, enum s_alloc what, static enum s_alloc __visit_domain_allocation_hell(struct s_data *d, const struct cpumask *cpu_map) { -#ifdef CONFIG_NUMA - if (!alloc_cpumask_var(&d->domainspan, GFP_KERNEL)) - return sa_none; - if (!alloc_cpumask_var(&d->covered, GFP_KERNEL)) - return sa_domainspan; - if (!alloc_cpumask_var(&d->notcovered, GFP_KERNEL)) - return sa_covered; - /* Allocate the per-node list of sched groups */ - d->sched_group_nodes = kcalloc(nr_node_ids, - sizeof(struct sched_group *), GFP_KERNEL); - if (!d->sched_group_nodes) { - printk(KERN_WARNING "Can not alloc sched group node list\n"); - return sa_notcovered; - } - sched_group_nodes_bycpu[cpumask_first(cpu_map)] = d->sched_group_nodes; -#endif - if (!alloc_cpumask_var(&d->nodemask, GFP_KERNEL)) - return sa_sched_group_nodes; - if (!alloc_cpumask_var(&d->this_sibling_map, GFP_KERNEL)) - return sa_nodemask; - if (!alloc_cpumask_var(&d->this_core_map, GFP_KERNEL)) - return sa_this_sibling_map; - if (!alloc_cpumask_var(&d->this_book_map, GFP_KERNEL)) - return sa_this_core_map; - if (!alloc_cpumask_var(&d->send_covered, GFP_KERNEL)) - return sa_this_book_map; - if (!alloc_cpumask_var(&d->tmpmask, GFP_KERNEL)) - return sa_send_covered; + memset(d, 0, sizeof(*d)); + + if (__sdt_alloc(cpu_map)) + return sa_sd_storage; + d->sd = alloc_percpu(struct sched_domain *); + if (!d->sd) + return sa_sd_storage; d->rd = alloc_rootdomain(); - if (!d->rd) { - printk(KERN_WARNING "Cannot alloc root domain\n"); - return sa_tmpmask; - } + if (!d->rd) + return sa_sd; return sa_rootdomain; } -static struct sched_domain *__build_numa_sched_domains(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, int i) +/* + * NULL the sd_data elements we've used to build the sched_domain and + * sched_group structure so that the subsequent __free_domain_allocs() + * will not free the data we're using. + */ +static void claim_allocations(int cpu, struct sched_domain *sd) { - struct sched_domain *sd = NULL; -#ifdef CONFIG_NUMA - struct sched_domain *parent; - - d->sd_allnodes = 0; - if (cpumask_weight(cpu_map) > - SD_NODES_PER_DOMAIN * cpumask_weight(d->nodemask)) { - sd = &per_cpu(allnodes_domains, i).sd; - SD_INIT(sd, ALLNODES); - set_domain_attribute(sd, attr); - cpumask_copy(sched_domain_span(sd), cpu_map); - cpu_to_allnodes_group(i, cpu_map, &sd->groups, d->tmpmask); - d->sd_allnodes = 1; - } - parent = sd; - - sd = &per_cpu(node_domains, i).sd; - SD_INIT(sd, NODE); - set_domain_attribute(sd, attr); - sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd)); - sd->parent = parent; - if (parent) - parent->child = sd; - cpumask_and(sched_domain_span(sd), sched_domain_span(sd), cpu_map); -#endif - return sd; -} + struct sd_data *sdd = sd->private; + struct sched_group *sg = sd->groups; -static struct sched_domain *__build_cpu_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) -{ - struct sched_domain *sd; - sd = &per_cpu(phys_domains, i).sd; - SD_INIT(sd, CPU); - set_domain_attribute(sd, attr); - cpumask_copy(sched_domain_span(sd), d->nodemask); - sd->parent = parent; - if (parent) - parent->child = sd; - cpu_to_phys_group(i, cpu_map, &sd->groups, d->tmpmask); - return sd; -} + WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd); + *per_cpu_ptr(sdd->sd, cpu) = NULL; -static struct sched_domain *__build_book_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) -{ - struct sched_domain *sd = parent; -#ifdef CONFIG_SCHED_BOOK - sd = &per_cpu(book_domains, i).sd; - SD_INIT(sd, BOOK); - set_domain_attribute(sd, attr); - cpumask_and(sched_domain_span(sd), cpu_map, cpu_book_mask(i)); - sd->parent = parent; - parent->child = sd; - cpu_to_book_group(i, cpu_map, &sd->groups, d->tmpmask); -#endif - return sd; + if (cpu == cpumask_first(sched_group_cpus(sg))) { + WARN_ON_ONCE(*per_cpu_ptr(sdd->sg, cpu) != sg); + *per_cpu_ptr(sdd->sg, cpu) = NULL; + } } -static struct sched_domain *__build_mc_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) +#ifdef CONFIG_SCHED_SMT +static const struct cpumask *cpu_smt_mask(int cpu) { - struct sched_domain *sd = parent; -#ifdef CONFIG_SCHED_MC - sd = &per_cpu(core_domains, i).sd; - SD_INIT(sd, MC); - set_domain_attribute(sd, attr); - cpumask_and(sched_domain_span(sd), cpu_map, cpu_coregroup_mask(i)); - sd->parent = parent; - parent->child = sd; - cpu_to_core_group(i, cpu_map, &sd->groups, d->tmpmask); -#endif - return sd; + return topology_thread_cpumask(cpu); } - -static struct sched_domain *__build_smt_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) -{ - struct sched_domain *sd = parent; -#ifdef CONFIG_SCHED_SMT - sd = &per_cpu(cpu_domains, i).sd; - SD_INIT(sd, SIBLING); - set_domain_attribute(sd, attr); - cpumask_and(sched_domain_span(sd), cpu_map, topology_thread_cpumask(i)); - sd->parent = parent; - parent->child = sd; - cpu_to_cpu_group(i, cpu_map, &sd->groups, d->tmpmask); #endif - return sd; -} -static void build_sched_groups(struct s_data *d, enum sched_domain_level l, - const struct cpumask *cpu_map, int cpu) -{ - switch (l) { +/* + * Topology list, bottom-up. + */ +static struct sched_domain_topology_level default_topology[] = { #ifdef CONFIG_SCHED_SMT - case SD_LV_SIBLING: /* set up CPU (sibling) groups */ - cpumask_and(d->this_sibling_map, cpu_map, - topology_thread_cpumask(cpu)); - if (cpu == cpumask_first(d->this_sibling_map)) - init_sched_build_groups(d->this_sibling_map, cpu_map, - &cpu_to_cpu_group, - d->send_covered, d->tmpmask); - break; + { sd_init_SIBLING, cpu_smt_mask, }, #endif #ifdef CONFIG_SCHED_MC - case SD_LV_MC: /* set up multi-core groups */ - cpumask_and(d->this_core_map, cpu_map, cpu_coregroup_mask(cpu)); - if (cpu == cpumask_first(d->this_core_map)) - init_sched_build_groups(d->this_core_map, cpu_map, - &cpu_to_core_group, - d->send_covered, d->tmpmask); - break; + { sd_init_MC, cpu_coregroup_mask, }, #endif #ifdef CONFIG_SCHED_BOOK - case SD_LV_BOOK: /* set up book groups */ - cpumask_and(d->this_book_map, cpu_map, cpu_book_mask(cpu)); - if (cpu == cpumask_first(d->this_book_map)) - init_sched_build_groups(d->this_book_map, cpu_map, - &cpu_to_book_group, - d->send_covered, d->tmpmask); - break; + { sd_init_BOOK, cpu_book_mask, }, #endif - case SD_LV_CPU: /* set up physical groups */ - cpumask_and(d->nodemask, cpumask_of_node(cpu), cpu_map); - if (!cpumask_empty(d->nodemask)) - init_sched_build_groups(d->nodemask, cpu_map, - &cpu_to_phys_group, - d->send_covered, d->tmpmask); - break; + { sd_init_CPU, cpu_cpu_mask, }, #ifdef CONFIG_NUMA - case SD_LV_ALLNODES: - init_sched_build_groups(cpu_map, cpu_map, &cpu_to_allnodes_group, - d->send_covered, d->tmpmask); - break; + { sd_init_NODE, cpu_node_mask, }, + { sd_init_ALLNODES, cpu_allnodes_mask, }, #endif - default: - break; + { NULL, }, +}; + +static struct sched_domain_topology_level *sched_domain_topology = default_topology; + +static int __sdt_alloc(const struct cpumask *cpu_map) +{ + struct sched_domain_topology_level *tl; + int j; + + for (tl = sched_domain_topology; tl->init; tl++) { + struct sd_data *sdd = &tl->data; + + sdd->sd = alloc_percpu(struct sched_domain *); + if (!sdd->sd) + return -ENOMEM; + + sdd->sg = alloc_percpu(struct sched_group *); + if (!sdd->sg) + return -ENOMEM; + + for_each_cpu(j, cpu_map) { + struct sched_domain *sd; + struct sched_group *sg; + + sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(), + GFP_KERNEL, cpu_to_node(j)); + if (!sd) + return -ENOMEM; + + *per_cpu_ptr(sdd->sd, j) = sd; + + sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), + GFP_KERNEL, cpu_to_node(j)); + if (!sg) + return -ENOMEM; + + *per_cpu_ptr(sdd->sg, j) = sg; + } + } + + return 0; +} + +static void __sdt_free(const struct cpumask *cpu_map) +{ + struct sched_domain_topology_level *tl; + int j; + + for (tl = sched_domain_topology; tl->init; tl++) { + struct sd_data *sdd = &tl->data; + + for_each_cpu(j, cpu_map) { + kfree(*per_cpu_ptr(sdd->sd, j)); + kfree(*per_cpu_ptr(sdd->sg, j)); + } + free_percpu(sdd->sd); + free_percpu(sdd->sg); + } +} + +struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, + struct s_data *d, const struct cpumask *cpu_map, + struct sched_domain_attr *attr, struct sched_domain *child, + int cpu) +{ + struct sched_domain *sd = tl->init(tl, cpu); + if (!sd) + return child; + + set_domain_attribute(sd, attr); + cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); + if (child) { + sd->level = child->level + 1; + sched_domain_level_max = max(sched_domain_level_max, sd->level); + child->parent = sd; } + sd->child = child; + + return sd; } /* * Build sched domains for a given set of cpus and attach the sched domains * to the individual cpus */ -static int __build_sched_domains(const struct cpumask *cpu_map, - struct sched_domain_attr *attr) +static int build_sched_domains(const struct cpumask *cpu_map, + struct sched_domain_attr *attr) { enum s_alloc alloc_state = sa_none; - struct s_data d; struct sched_domain *sd; - int i; -#ifdef CONFIG_NUMA - d.sd_allnodes = 0; -#endif + struct s_data d; + int i, ret = -ENOMEM; alloc_state = __visit_domain_allocation_hell(&d, cpu_map); if (alloc_state != sa_rootdomain) goto error; - alloc_state = sa_sched_groups; - /* - * Set up domains for cpus specified by the cpu_map. - */ + /* Set up domains for cpus specified by the cpu_map. */ for_each_cpu(i, cpu_map) { - cpumask_and(d.nodemask, cpumask_of_node(cpu_to_node(i)), - cpu_map); + struct sched_domain_topology_level *tl; - sd = __build_numa_sched_domains(&d, cpu_map, attr, i); - sd = __build_cpu_sched_domain(&d, cpu_map, attr, sd, i); - sd = __build_book_sched_domain(&d, cpu_map, attr, sd, i); - sd = __build_mc_sched_domain(&d, cpu_map, attr, sd, i); - sd = __build_smt_sched_domain(&d, cpu_map, attr, sd, i); - } - - for_each_cpu(i, cpu_map) { - build_sched_groups(&d, SD_LV_SIBLING, cpu_map, i); - build_sched_groups(&d, SD_LV_BOOK, cpu_map, i); - build_sched_groups(&d, SD_LV_MC, cpu_map, i); - } - - /* Set up physical groups */ - for (i = 0; i < nr_node_ids; i++) - build_sched_groups(&d, SD_LV_CPU, cpu_map, i); + sd = NULL; + for (tl = sched_domain_topology; tl->init; tl++) + sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); -#ifdef CONFIG_NUMA - /* Set up node groups */ - if (d.sd_allnodes) - build_sched_groups(&d, SD_LV_ALLNODES, cpu_map, 0); - - for (i = 0; i < nr_node_ids; i++) - if (build_numa_sched_groups(&d, cpu_map, i)) - goto error; -#endif + while (sd->child) + sd = sd->child; - /* Calculate CPU power for physical packages and nodes */ -#ifdef CONFIG_SCHED_SMT - for_each_cpu(i, cpu_map) { - sd = &per_cpu(cpu_domains, i).sd; - init_sched_groups_power(i, sd); - } -#endif -#ifdef CONFIG_SCHED_MC - for_each_cpu(i, cpu_map) { - sd = &per_cpu(core_domains, i).sd; - init_sched_groups_power(i, sd); + *per_cpu_ptr(d.sd, i) = sd; } -#endif -#ifdef CONFIG_SCHED_BOOK - for_each_cpu(i, cpu_map) { - sd = &per_cpu(book_domains, i).sd; - init_sched_groups_power(i, sd); - } -#endif + /* Build the groups for the domains */ for_each_cpu(i, cpu_map) { - sd = &per_cpu(phys_domains, i).sd; - init_sched_groups_power(i, sd); - } + for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { + sd->span_weight = cpumask_weight(sched_domain_span(sd)); + get_group(i, sd->private, &sd->groups); + atomic_inc(&sd->groups->ref); -#ifdef CONFIG_NUMA - for (i = 0; i < nr_node_ids; i++) - init_numa_sched_groups_power(d.sched_group_nodes[i]); + if (i != cpumask_first(sched_domain_span(sd))) + continue; - if (d.sd_allnodes) { - struct sched_group *sg; + build_sched_groups(sd); + } + } - cpu_to_allnodes_group(cpumask_first(cpu_map), cpu_map, &sg, - d.tmpmask); - init_numa_sched_groups_power(sg); + /* Calculate CPU power for physical packages and nodes */ + for (i = nr_cpumask_bits-1; i >= 0; i--) { + if (!cpumask_test_cpu(i, cpu_map)) + continue; + + for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { + claim_allocations(i, sd); + init_sched_groups_power(i, sd); + } } -#endif /* Attach the domains */ + rcu_read_lock(); for_each_cpu(i, cpu_map) { -#ifdef CONFIG_SCHED_SMT - sd = &per_cpu(cpu_domains, i).sd; -#elif defined(CONFIG_SCHED_MC) - sd = &per_cpu(core_domains, i).sd; -#elif defined(CONFIG_SCHED_BOOK) - sd = &per_cpu(book_domains, i).sd; -#else - sd = &per_cpu(phys_domains, i).sd; -#endif + sd = *per_cpu_ptr(d.sd, i); cpu_attach_domain(sd, d.rd, i); } + rcu_read_unlock(); - d.sched_group_nodes = NULL; /* don't free this we still need it */ - __free_domain_allocs(&d, sa_tmpmask, cpu_map); - return 0; - + ret = 0; error: __free_domain_allocs(&d, alloc_state, cpu_map); - return -ENOMEM; -} - -static int build_sched_domains(const struct cpumask *cpu_map) -{ - return __build_sched_domains(cpu_map, NULL); + return ret; } static cpumask_var_t *doms_cur; /* current sched domains */ @@ -7670,7 +7362,7 @@ void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms) * For now this just excludes isolated cpus, but could be used to * exclude other special cases in the future. */ -static int arch_init_sched_domains(const struct cpumask *cpu_map) +static int init_sched_domains(const struct cpumask *cpu_map) { int err; @@ -7681,32 +7373,24 @@ static int arch_init_sched_domains(const struct cpumask *cpu_map) doms_cur = &fallback_doms; cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map); dattr_cur = NULL; - err = build_sched_domains(doms_cur[0]); + err = build_sched_domains(doms_cur[0], NULL); register_sched_domain_sysctl(); return err; } -static void arch_destroy_sched_domains(const struct cpumask *cpu_map, - struct cpumask *tmpmask) -{ - free_sched_groups(cpu_map, tmpmask); -} - /* * Detach sched domains from a group of cpus specified in cpu_map * These cpus will now be attached to the NULL domain */ static void detach_destroy_domains(const struct cpumask *cpu_map) { - /* Save because hotplug lock held. */ - static DECLARE_BITMAP(tmpmask, CONFIG_NR_CPUS); int i; + rcu_read_lock(); for_each_cpu(i, cpu_map) cpu_attach_domain(NULL, &def_root_domain, i); - synchronize_sched(); - arch_destroy_sched_domains(cpu_map, to_cpumask(tmpmask)); + rcu_read_unlock(); } /* handle null as "default" */ @@ -7795,8 +7479,7 @@ match1: goto match2; } /* no match - add a new doms_new */ - __build_sched_domains(doms_new[i], - dattr_new ? dattr_new + i : NULL); + build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL); match2: ; } @@ -7815,7 +7498,7 @@ match2: } #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) -static void arch_reinit_sched_domains(void) +static void reinit_sched_domains(void) { get_online_cpus(); @@ -7848,7 +7531,7 @@ static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt) else sched_mc_power_savings = level; - arch_reinit_sched_domains(); + reinit_sched_domains(); return count; } @@ -7967,14 +7650,9 @@ void __init sched_init_smp(void) alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL); alloc_cpumask_var(&fallback_doms, GFP_KERNEL); -#if defined(CONFIG_NUMA) - sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **), - GFP_KERNEL); - BUG_ON(sched_group_nodes_bycpu == NULL); -#endif get_online_cpus(); mutex_lock(&sched_domains_mutex); - arch_init_sched_domains(cpu_active_mask); + init_sched_domains(cpu_active_mask); cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map); if (cpumask_empty(non_isolated_cpus)) cpumask_set_cpu(smp_processor_id(), non_isolated_cpus); @@ -8281,6 +7959,7 @@ void __init sched_init(void) /* Allocate the nohz_cpu_mask if CONFIG_CPUMASK_OFFSTACK */ zalloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT); #ifdef CONFIG_SMP + zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); #ifdef CONFIG_NO_HZ zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); alloc_cpumask_var(&nohz.grp_idle_mask, GFP_NOWAIT); @@ -8340,7 +8019,7 @@ static void normalize_task(struct rq *rq, struct task_struct *p) int old_prio = p->prio; int on_rq; - on_rq = p->se.on_rq; + on_rq = p->on_rq; if (on_rq) deactivate_task(rq, p, 0); __setscheduler(rq, p, SCHED_NORMAL, 0); @@ -8553,7 +8232,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) { struct rt_rq *rt_rq; struct sched_rt_entity *rt_se; - struct rq *rq; int i; tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL); @@ -8567,8 +8245,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) ktime_to_ns(def_rt_bandwidth.rt_period), 0); for_each_possible_cpu(i) { - rq = cpu_rq(i); - rt_rq = kzalloc_node(sizeof(struct rt_rq), GFP_KERNEL, cpu_to_node(i)); if (!rt_rq) @@ -8683,7 +8359,7 @@ void sched_move_task(struct task_struct *tsk) rq = task_rq_lock(tsk, &flags); running = task_current(rq, tsk); - on_rq = tsk->se.on_rq; + on_rq = tsk->on_rq; if (on_rq) dequeue_task(rq, tsk, 0); @@ -8702,7 +8378,7 @@ void sched_move_task(struct task_struct *tsk) if (on_rq) enqueue_task(rq, tsk, 0); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, tsk, &flags); } #endif /* CONFIG_CGROUP_SCHED */ diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c index 7bacd83..a6710a1 100644 --- a/kernel/sched_debug.c +++ b/kernel/sched_debug.c @@ -152,7 +152,7 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu) read_lock_irqsave(&tasklist_lock, flags); do_each_thread(g, p) { - if (!p->se.on_rq || task_cpu(p) != rq_cpu) + if (!p->on_rq || task_cpu(p) != rq_cpu) continue; print_task(m, rq, p); @@ -296,9 +296,6 @@ static void print_cpu(struct seq_file *m, int cpu) P(ttwu_count); P(ttwu_local); - SEQ_printf(m, " .%-30s: %d\n", "bkl_count", - rq->rq_sched_info.bkl_count); - #undef P #undef P64 #endif @@ -441,7 +438,6 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m) P(se.statistics.wait_count); PN(se.statistics.iowait_sum); P(se.statistics.iowait_count); - P(sched_info.bkl_count); P(se.nr_migrations); P(se.statistics.nr_migrations_cold); P(se.statistics.nr_failed_migrations_affine); diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 6fa833a..37f2262 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -358,6 +358,10 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq) } cfs_rq->min_vruntime = max_vruntime(cfs_rq->min_vruntime, vruntime); +#ifndef CONFIG_64BIT + smp_wmb(); + cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime; +#endif } /* @@ -1340,6 +1344,8 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags) hrtick_update(rq); } +static void set_next_buddy(struct sched_entity *se); + /* * The dequeue_task method is called before nr_running is * decreased. We remove the task from the rbtree and @@ -1349,14 +1355,22 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) { struct cfs_rq *cfs_rq; struct sched_entity *se = &p->se; + int task_sleep = flags & DEQUEUE_SLEEP; for_each_sched_entity(se) { cfs_rq = cfs_rq_of(se); dequeue_entity(cfs_rq, se, flags); /* Don't dequeue parent if it has other entities besides us */ - if (cfs_rq->load.weight) + if (cfs_rq->load.weight) { + /* + * Bias pick_next to pick a task from this cfs_rq, as + * p is sleeping when it is within its sched_slice. + */ + if (task_sleep && parent_entity(se)) + set_next_buddy(parent_entity(se)); break; + } flags |= DEQUEUE_SLEEP; } @@ -1372,12 +1386,25 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) #ifdef CONFIG_SMP -static void task_waking_fair(struct rq *rq, struct task_struct *p) +static void task_waking_fair(struct task_struct *p) { struct sched_entity *se = &p->se; struct cfs_rq *cfs_rq = cfs_rq_of(se); + u64 min_vruntime; - se->vruntime -= cfs_rq->min_vruntime; +#ifndef CONFIG_64BIT + u64 min_vruntime_copy; + + do { + min_vruntime_copy = cfs_rq->min_vruntime_copy; + smp_rmb(); + min_vruntime = cfs_rq->min_vruntime; + } while (min_vruntime != min_vruntime_copy); +#else + min_vruntime = cfs_rq->min_vruntime; +#endif + + se->vruntime -= min_vruntime; } #ifdef CONFIG_FAIR_GROUP_SCHED @@ -1622,6 +1649,7 @@ static int select_idle_sibling(struct task_struct *p, int target) /* * Otherwise, iterate the domains and find an elegible idle cpu. */ + rcu_read_lock(); for_each_domain(target, sd) { if (!(sd->flags & SD_SHARE_PKG_RESOURCES)) break; @@ -1641,6 +1669,7 @@ static int select_idle_sibling(struct task_struct *p, int target) cpumask_test_cpu(prev_cpu, sched_domain_span(sd))) break; } + rcu_read_unlock(); return target; } @@ -1657,7 +1686,7 @@ static int select_idle_sibling(struct task_struct *p, int target) * preempt must be disabled. */ static int -select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_flags) +select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags) { struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL; int cpu = smp_processor_id(); @@ -1673,6 +1702,7 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_ new_cpu = prev_cpu; } + rcu_read_lock(); for_each_domain(cpu, tmp) { if (!(tmp->flags & SD_LOAD_BALANCE)) continue; @@ -1723,9 +1753,10 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_ if (affine_sd) { if (cpu == prev_cpu || wake_affine(affine_sd, p, sync)) - return select_idle_sibling(p, cpu); - else - return select_idle_sibling(p, prev_cpu); + prev_cpu = cpu; + + new_cpu = select_idle_sibling(p, prev_cpu); + goto unlock; } while (sd) { @@ -1766,6 +1797,8 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_ } /* while loop will break here if sd == NULL */ } +unlock: + rcu_read_unlock(); return new_cpu; } @@ -1789,10 +1822,7 @@ wakeup_gran(struct sched_entity *curr, struct sched_entity *se) * This is especially important for buddies when the leftmost * task is higher priority than the buddy. */ - if (unlikely(se->load.weight != NICE_0_LOAD)) - gran = calc_delta_fair(gran, se); - - return gran; + return calc_delta_fair(gran, se); } /* @@ -1826,26 +1856,26 @@ wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se) static void set_last_buddy(struct sched_entity *se) { - if (likely(task_of(se)->policy != SCHED_IDLE)) { - for_each_sched_entity(se) - cfs_rq_of(se)->last = se; - } + if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE)) + return; + + for_each_sched_entity(se) + cfs_rq_of(se)->last = se; } static void set_next_buddy(struct sched_entity *se) { - if (likely(task_of(se)->policy != SCHED_IDLE)) { - for_each_sched_entity(se) - cfs_rq_of(se)->next = se; - } + if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE)) + return; + + for_each_sched_entity(se) + cfs_rq_of(se)->next = se; } static void set_skip_buddy(struct sched_entity *se) { - if (likely(task_of(se)->policy != SCHED_IDLE)) { - for_each_sched_entity(se) - cfs_rq_of(se)->skip = se; - } + for_each_sched_entity(se) + cfs_rq_of(se)->skip = se; } /* @@ -1857,12 +1887,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ struct sched_entity *se = &curr->se, *pse = &p->se; struct cfs_rq *cfs_rq = task_cfs_rq(curr); int scale = cfs_rq->nr_running >= sched_nr_latency; + int next_buddy_marked = 0; if (unlikely(se == pse)) return; - if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK)) + if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK)) { set_next_buddy(pse); + next_buddy_marked = 1; + } /* * We can come here with TIF_NEED_RESCHED already set from new task @@ -1890,8 +1923,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ update_curr(cfs_rq); find_matching_se(&se, &pse); BUG_ON(!pse); - if (wakeup_preempt_entity(se, pse) == 1) + if (wakeup_preempt_entity(se, pse) == 1) { + /* + * Bias pick_next to pick the sched entity that is + * triggering this preemption. + */ + if (!next_buddy_marked) + set_next_buddy(pse); goto preempt; + } return; @@ -2102,7 +2142,7 @@ static unsigned long balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, int *all_pinned, - int *this_best_prio, struct cfs_rq *busiest_cfs_rq) + struct cfs_rq *busiest_cfs_rq) { int loops = 0, pulled = 0; long rem_load_move = max_load_move; @@ -2140,9 +2180,6 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, */ if (rem_load_move <= 0) break; - - if (p->prio < *this_best_prio) - *this_best_prio = p->prio; } out: /* @@ -2202,7 +2239,7 @@ static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, int *this_best_prio) + int *all_pinned) { long rem_load_move = max_load_move; int busiest_cpu = cpu_of(busiest); @@ -2227,7 +2264,7 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, rem_load = div_u64(rem_load, busiest_h_load + 1); moved_load = balance_tasks(this_rq, this_cpu, busiest, - rem_load, sd, idle, all_pinned, this_best_prio, + rem_load, sd, idle, all_pinned, busiest_cfs_rq); if (!moved_load) @@ -2253,11 +2290,11 @@ static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, int *this_best_prio) + int *all_pinned) { return balance_tasks(this_rq, this_cpu, busiest, max_load_move, sd, idle, all_pinned, - this_best_prio, &busiest->cfs); + &busiest->cfs); } #endif @@ -2274,12 +2311,11 @@ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, int *all_pinned) { unsigned long total_load_moved = 0, load_moved; - int this_best_prio = this_rq->curr->prio; do { load_moved = load_balance_fair(this_rq, this_cpu, busiest, max_load_move - total_load_moved, - sd, idle, all_pinned, &this_best_prio); + sd, idle, all_pinned); total_load_moved += load_moved; @@ -2648,7 +2684,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group) /* * Only siblings can have significantly less than SCHED_LOAD_SCALE */ - if (sd->level != SD_LV_SIBLING) + if (!(sd->flags & SD_SHARE_CPUPOWER)) return 0; /* @@ -3465,6 +3501,7 @@ static void idle_balance(int this_cpu, struct rq *this_rq) raw_spin_unlock(&this_rq->lock); update_shares(this_cpu); + rcu_read_lock(); for_each_domain(this_cpu, sd) { unsigned long interval; int balance = 1; @@ -3486,6 +3523,7 @@ static void idle_balance(int this_cpu, struct rq *this_rq) break; } } + rcu_read_unlock(); raw_spin_lock(&this_rq->lock); @@ -3534,6 +3572,7 @@ static int active_load_balance_cpu_stop(void *data) double_lock_balance(busiest_rq, target_rq); /* Search for an sd spanning us and the target CPU. */ + rcu_read_lock(); for_each_domain(target_cpu, sd) { if ((sd->flags & SD_LOAD_BALANCE) && cpumask_test_cpu(busiest_cpu, sched_domain_span(sd))) @@ -3549,6 +3588,7 @@ static int active_load_balance_cpu_stop(void *data) else schedstat_inc(sd, alb_failed); } + rcu_read_unlock(); double_unlock_balance(busiest_rq, target_rq); out_unlock: busiest_rq->active_balance = 0; @@ -3675,6 +3715,7 @@ static int find_new_ilb(int cpu) { struct sched_domain *sd; struct sched_group *ilb_group; + int ilb = nr_cpu_ids; /* * Have idle load balancer selection from semi-idle packages only @@ -3690,20 +3731,25 @@ static int find_new_ilb(int cpu) if (cpumask_weight(nohz.idle_cpus_mask) < 2) goto out_done; + rcu_read_lock(); for_each_flag_domain(cpu, sd, SD_POWERSAVINGS_BALANCE) { ilb_group = sd->groups; do { - if (is_semi_idle_group(ilb_group)) - return cpumask_first(nohz.grp_idle_mask); + if (is_semi_idle_group(ilb_group)) { + ilb = cpumask_first(nohz.grp_idle_mask); + goto unlock; + } ilb_group = ilb_group->next; } while (ilb_group != sd->groups); } +unlock: + rcu_read_unlock(); out_done: - return nr_cpu_ids; + return ilb; } #else /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */ static inline int find_new_ilb(int call_cpu) @@ -3848,6 +3894,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle) update_shares(cpu); + rcu_read_lock(); for_each_domain(cpu, sd) { if (!(sd->flags & SD_LOAD_BALANCE)) continue; @@ -3893,6 +3940,7 @@ out: if (!balance) break; } + rcu_read_unlock(); /* * next_balance will be updated only when there is a need. diff --git a/kernel/sched_features.h b/kernel/sched_features.h index 68e69ac..be40f73 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -64,3 +64,9 @@ SCHED_FEAT(OWNER_SPIN, 1) * Decrement CPU power based on irq activity */ SCHED_FEAT(NONIRQ_POWER, 1) + +/* + * Queue remote wakeups on the target CPU and process them + * using the scheduler IPI. Reduces rq->lock contention/bounces. + */ +SCHED_FEAT(TTWU_QUEUE, 1) diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c index a776a63..0a51882 100644 --- a/kernel/sched_idletask.c +++ b/kernel/sched_idletask.c @@ -7,7 +7,7 @@ #ifdef CONFIG_SMP static int -select_task_rq_idle(struct rq *rq, struct task_struct *p, int sd_flag, int flags) +select_task_rq_idle(struct task_struct *p, int sd_flag, int flags) { return task_cpu(p); /* IDLE tasks as never migrated */ } diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index e7cebdc..64b2a37 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -183,6 +183,14 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq) return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period); } +typedef struct task_group *rt_rq_iter_t; + +#define for_each_rt_rq(rt_rq, iter, rq) \ + for (iter = list_entry_rcu(task_groups.next, typeof(*iter), list); \ + (&iter->list != &task_groups) && \ + (rt_rq = iter->rt_rq[cpu_of(rq)]); \ + iter = list_entry_rcu(iter->list.next, typeof(*iter), list)) + static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq) { list_add_rcu(&rt_rq->leaf_rt_rq_list, @@ -288,6 +296,11 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq) return ktime_to_ns(def_rt_bandwidth.rt_period); } +typedef struct rt_rq *rt_rq_iter_t; + +#define for_each_rt_rq(rt_rq, iter, rq) \ + for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL) + static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq) { } @@ -402,12 +415,13 @@ next: static void __disable_runtime(struct rq *rq) { struct root_domain *rd = rq->rd; + rt_rq_iter_t iter; struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) return; - for_each_leaf_rt_rq(rt_rq, rq) { + for_each_rt_rq(rt_rq, iter, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); s64 want; int i; @@ -487,6 +501,7 @@ static void disable_runtime(struct rq *rq) static void __enable_runtime(struct rq *rq) { + rt_rq_iter_t iter; struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) @@ -495,7 +510,7 @@ static void __enable_runtime(struct rq *rq) /* * Reset each runqueue's bandwidth settings */ - for_each_leaf_rt_rq(rt_rq, rq) { + for_each_rt_rq(rt_rq, iter, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); raw_spin_lock(&rt_b->rt_runtime_lock); @@ -562,6 +577,13 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun) if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) { rt_rq->rt_throttled = 0; enqueue = 1; + + /* + * Force a clock update if the CPU was idle, + * lest wakeup -> unthrottle time accumulate. + */ + if (rt_rq->rt_nr_running && rq->curr == rq->idle) + rq->skip_clock_update = -1; } if (rt_rq->rt_time || rt_rq->rt_nr_running) idle = 0; @@ -977,13 +999,23 @@ static void yield_task_rt(struct rq *rq) static int find_lowest_rq(struct task_struct *task); static int -select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags) +select_task_rq_rt(struct task_struct *p, int sd_flag, int flags) { + struct task_struct *curr; + struct rq *rq; + int cpu; + if (sd_flag != SD_BALANCE_WAKE) return smp_processor_id(); + cpu = task_cpu(p); + rq = cpu_rq(cpu); + + rcu_read_lock(); + curr = ACCESS_ONCE(rq->curr); /* unlocked access */ + /* - * If the current task is an RT task, then + * If the current task on @p's runqueue is an RT task, then * try to see if we can wake this RT task up on another * runqueue. Otherwise simply start this RT task * on its current runqueue. @@ -997,21 +1029,25 @@ select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags) * lock? * * For equal prio tasks, we just let the scheduler sort it out. + * + * Otherwise, just let it ride on the affined RQ and the + * post-schedule router will push the preempted task away + * + * This test is optimistic, if we get it wrong the load-balancer + * will have to sort it out. */ - if (unlikely(rt_task(rq->curr)) && - (rq->curr->rt.nr_cpus_allowed < 2 || - rq->curr->prio < p->prio) && + if (curr && unlikely(rt_task(curr)) && + (curr->rt.nr_cpus_allowed < 2 || + curr->prio < p->prio) && (p->rt.nr_cpus_allowed > 1)) { - int cpu = find_lowest_rq(p); + int target = find_lowest_rq(p); - return (cpu == -1) ? task_cpu(p) : cpu; + if (target != -1) + cpu = target; } + rcu_read_unlock(); - /* - * Otherwise, just let it ride on the affined RQ and the - * post-schedule router will push the preempted task away - */ - return task_cpu(p); + return cpu; } static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p) @@ -1136,7 +1172,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p) * The previous task needs to be made eligible for pushing * if it is still active */ - if (p->se.on_rq && p->rt.nr_cpus_allowed > 1) + if (on_rt_rq(&p->rt) && p->rt.nr_cpus_allowed > 1) enqueue_pushable_task(rq, p); } @@ -1287,7 +1323,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq) !cpumask_test_cpu(lowest_rq->cpu, &task->cpus_allowed) || task_running(rq, task) || - !task->se.on_rq)) { + !task->on_rq)) { raw_spin_unlock(&lowest_rq->lock); lowest_rq = NULL; @@ -1321,7 +1357,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq) BUG_ON(task_current(rq, p)); BUG_ON(p->rt.nr_cpus_allowed <= 1); - BUG_ON(!p->se.on_rq); + BUG_ON(!p->on_rq); BUG_ON(!rt_task(p)); return p; @@ -1467,7 +1503,7 @@ static int pull_rt_task(struct rq *this_rq) */ if (p && (p->prio < this_rq->rt.highest_prio.curr)) { WARN_ON(p == src_rq->curr); - WARN_ON(!p->se.on_rq); + WARN_ON(!p->on_rq); /* * There's a chance that p is higher in priority @@ -1538,7 +1574,7 @@ static void set_cpus_allowed_rt(struct task_struct *p, * Update the migration status of the RQ if we have an RT task * which is running AND changing its weight value. */ - if (p->se.on_rq && (weight != p->rt.nr_cpus_allowed)) { + if (p->on_rq && (weight != p->rt.nr_cpus_allowed)) { struct rq *rq = task_rq(p); if (!task_current(rq, p)) { @@ -1608,7 +1644,7 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p) * we may need to handle the pulling of RT tasks * now. */ - if (p->se.on_rq && !rq->rt.rt_nr_running) + if (p->on_rq && !rq->rt.rt_nr_running) pull_rt_task(rq); } @@ -1638,7 +1674,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p) * If that current running task is also an RT task * then see if we can move to another run queue. */ - if (p->se.on_rq && rq->curr != p) { + if (p->on_rq && rq->curr != p) { #ifdef CONFIG_SMP if (rq->rt.overloaded && push_rt_task(rq) && /* Don't resched if we changed runqueues */ @@ -1657,7 +1693,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p) static void prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio) { - if (!p->se.on_rq) + if (!p->on_rq) return; if (rq->curr == p) { @@ -1796,10 +1832,11 @@ extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); static void print_rt_stats(struct seq_file *m, int cpu) { + rt_rq_iter_t iter; struct rt_rq *rt_rq; rcu_read_lock(); - for_each_leaf_rt_rq(rt_rq, cpu_rq(cpu)) + for_each_rt_rq(rt_rq, iter, cpu_rq(cpu)) print_rt_rq(m, cpu, rt_rq); rcu_read_unlock(); } diff --git a/kernel/sched_stoptask.c b/kernel/sched_stoptask.c index 1ba2bd4..6f43763 100644 --- a/kernel/sched_stoptask.c +++ b/kernel/sched_stoptask.c @@ -9,8 +9,7 @@ #ifdef CONFIG_SMP static int -select_task_rq_stop(struct rq *rq, struct task_struct *p, - int sd_flag, int flags) +select_task_rq_stop(struct task_struct *p, int sd_flag, int flags) { return task_cpu(p); /* stop tasks as never migrate */ } @@ -26,7 +25,7 @@ static struct task_struct *pick_next_task_stop(struct rq *rq) { struct task_struct *stop = rq->stop; - if (stop && stop->se.on_rq) + if (stop && stop->on_rq) return stop; return NULL; diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 35d55a3..f925c45 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -53,7 +53,6 @@ const char *reserved_field_names[] = { "common_preempt_count", "common_pid", "common_tgid", - "common_lock_depth", FIELD_STRING_IP, FIELD_STRING_RETIP, FIELD_STRING_FUNC, diff --git a/tools/perf/Documentation/perf-script-perl.txt b/tools/perf/Documentation/perf-script-perl.txt index 5bb41e5..3152cca 100644 --- a/tools/perf/Documentation/perf-script-perl.txt +++ b/tools/perf/Documentation/perf-script-perl.txt @@ -63,7 +63,6 @@ The format file for the sched_wakep event defines the following fields field:unsigned char common_flags; field:unsigned char common_preempt_count; field:int common_pid; - field:int common_lock_depth; field:char comm[TASK_COMM_LEN]; field:pid_t pid; diff --git a/tools/perf/Documentation/perf-script-python.txt b/tools/perf/Documentation/perf-script-python.txt index 36b3827..4710220 100644 --- a/tools/perf/Documentation/perf-script-python.txt +++ b/tools/perf/Documentation/perf-script-python.txt @@ -463,7 +463,6 @@ The format file for the sched_wakep event defines the following fields field:unsigned char common_flags; field:unsigned char common_preempt_count; field:int common_pid; - field:int common_lock_depth; field:char comm[TASK_COMM_LEN]; field:pid_t pid; |
