Merge branch 'kvm-updates/3.0' of git://git.kernel.org/pub/scm/virt/kvm/kvm
authorLinus Torvalds <torvalds@linux-foundation.org>
Mon, 20 Jun 2011 15:58:07 +0000 (08:58 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 20 Jun 2011 15:58:07 +0000 (08:58 -0700)
* 'kvm-updates/3.0' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Fix register corruption in pvclock_scale_delta
  KVM: MMU: fix opposite condition in mapping_level_dirty_bitmap
  KVM: VMX: do not overwrite uptodate vcpu->arch.cr3 on KVM_SET_SREGS
  KVM: MMU: Fix build warnings in walk_addr_generic()

21 files changed:
Documentation/filesystems/proc.txt
MAINTAINERS
arch/x86/include/asm/memblock.h
arch/x86/mm/memblock.c
arch/x86/platform/efi/efi.c
fs/timerfd.c
include/linux/clocksource.h
include/linux/interrupt.h
include/linux/smp.h
include/trace/events/irq.h
init/main.c
kernel/rcutree.c
kernel/rcutree.h
kernel/rcutree_plugin.h
kernel/rcutree_trace.c
kernel/smp.c
kernel/softirq.c
kernel/time/clocksource.c
kernel/trace/trace_printk.c
tools/perf/Makefile
tools/perf/util/trace-event-parse.c

index f481780..db3b1ab 100644 (file)
@@ -843,6 +843,7 @@ Provides counts of softirq handlers serviced since boot time, for each cpu.
  TASKLET:          0          0          0        290
    SCHED:      27035      26983      26971      26746
  HRTIMER:          0          0          0          0
+     RCU:       1678       1769       2178       2250
 
 
 1.3 IDE devices in /proc/ide
index 502f2dd..b12b8c1 100644 (file)
@@ -7007,6 +7007,13 @@ T:       git git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86.
 S:     Maintained
 F:     drivers/platform/x86
 
+X86 MCE INFRASTRUCTURE
+M:     Tony Luck <tony.luck@intel.com>
+M:     Borislav Petkov <bp@amd64.org>
+L:     linux-edac@vger.kernel.org
+S:     Maintained
+F:     arch/x86/kernel/cpu/mcheck/*
+
 XEN HYPERVISOR INTERFACE
 M:     Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
 M:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
index 19ae14b..0cd3800 100644 (file)
@@ -4,7 +4,6 @@
 #define ARCH_DISCARD_MEMBLOCK
 
 u64 memblock_x86_find_in_range_size(u64 start, u64 *sizep, u64 align);
-void memblock_x86_to_bootmem(u64 start, u64 end);
 
 void memblock_x86_reserve_range(u64 start, u64 end, char *name);
 void memblock_x86_free_range(u64 start, u64 end);
@@ -19,5 +18,6 @@ u64 memblock_x86_hole_size(u64 start, u64 end);
 u64 memblock_x86_find_in_range_node(int nid, u64 start, u64 end, u64 size, u64 align);
 u64 memblock_x86_free_memory_in_range(u64 addr, u64 limit);
 u64 memblock_x86_memory_in_range(u64 addr, u64 limit);
+bool memblock_x86_check_reserved_size(u64 *addrp, u64 *sizep, u64 align);
 
 #endif
index aa11693..992da5e 100644 (file)
@@ -8,7 +8,7 @@
 #include <linux/range.h>
 
 /* Check for already reserved areas */
-static bool __init check_with_memblock_reserved_size(u64 *addrp, u64 *sizep, u64 align)
+bool __init memblock_x86_check_reserved_size(u64 *addrp, u64 *sizep, u64 align)
 {
        struct memblock_region *r;
        u64 addr = *addrp, last;
@@ -59,7 +59,7 @@ u64 __init memblock_x86_find_in_range_size(u64 start, u64 *sizep, u64 align)
                if (addr >= ei_last)
                        continue;
                *sizep = ei_last - addr;
-               while (check_with_memblock_reserved_size(&addr, sizep, align))
+               while (memblock_x86_check_reserved_size(&addr, sizep, align))
                        ;
 
                if (*sizep)
index 0d3a4fa..474356b 100644 (file)
@@ -310,14 +310,31 @@ void __init efi_reserve_boot_services(void)
 
        for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
                efi_memory_desc_t *md = p;
-               unsigned long long start = md->phys_addr;
-               unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+               u64 start = md->phys_addr;
+               u64 size = md->num_pages << EFI_PAGE_SHIFT;
 
                if (md->type != EFI_BOOT_SERVICES_CODE &&
                    md->type != EFI_BOOT_SERVICES_DATA)
                        continue;
-
-               memblock_x86_reserve_range(start, start + size, "EFI Boot");
+               /* Only reserve where possible:
+                * - Not within any already allocated areas
+                * - Not over any memory area (really needed, if above?)
+                * - Not within any part of the kernel
+                * - Not the bios reserved area
+               */
+               if ((start+size >= virt_to_phys(_text)
+                               && start <= virt_to_phys(_end)) ||
+                       !e820_all_mapped(start, start+size, E820_RAM) ||
+                       memblock_x86_check_reserved_size(&start, &size,
+                                                       1<<EFI_PAGE_SHIFT)) {
+                       /* Could not reserve, skip it */
+                       md->num_pages = 0;
+                       memblock_dbg(PFX "Could not reserve boot range "
+                                       "[0x%010llx-0x%010llx]\n",
+                                               start, start+size-1);
+               } else
+                       memblock_x86_reserve_range(start, start+size,
+                                                       "EFI Boot");
        }
 }
 
@@ -334,6 +351,10 @@ static void __init efi_free_boot_services(void)
                    md->type != EFI_BOOT_SERVICES_DATA)
                        continue;
 
+               /* Could not reserve boot area */
+               if (!size)
+                       continue;
+
                free_bootmem_late(start, size);
        }
 }
index f67acbd..dffeb37 100644 (file)
@@ -61,7 +61,9 @@ static enum hrtimer_restart timerfd_tmrproc(struct hrtimer *htmr)
 
 /*
  * Called when the clock was set to cancel the timers in the cancel
- * list.
+ * list. This will wake up processes waiting on these timers. The
+ * wake-up requires ctx->ticks to be non zero, therefore we increment
+ * it before calling wake_up_locked().
  */
 void timerfd_clock_was_set(void)
 {
@@ -76,6 +78,7 @@ void timerfd_clock_was_set(void)
                spin_lock_irqsave(&ctx->wqh.lock, flags);
                if (ctx->moffs.tv64 != moffs.tv64) {
                        ctx->moffs.tv64 = KTIME_MAX;
+                       ctx->ticks++;
                        wake_up_locked(&ctx->wqh);
                }
                spin_unlock_irqrestore(&ctx->wqh.lock, flags);
index d4646b4..18a1baf 100644 (file)
@@ -188,6 +188,7 @@ struct clocksource {
 #ifdef CONFIG_CLOCKSOURCE_WATCHDOG
        /* Watchdog related data, used by the framework */
        struct list_head wd_list;
+       cycle_t cs_last;
        cycle_t wd_last;
 #endif
 } ____cacheline_aligned;
index 6c12989..f6efed0 100644 (file)
@@ -414,6 +414,7 @@ enum
        TASKLET_SOFTIRQ,
        SCHED_SOFTIRQ,
        HRTIMER_SOFTIRQ,
+       RCU_SOFTIRQ,    /* Preferable RCU should always be the last softirq */
 
        NR_SOFTIRQS
 };
index 7ad824d..8cc38d3 100644 (file)
@@ -85,12 +85,15 @@ int smp_call_function_any(const struct cpumask *mask,
  * Generic and arch helpers
  */
 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
+void __init call_function_init(void);
 void generic_smp_call_function_single_interrupt(void);
 void generic_smp_call_function_interrupt(void);
 void ipi_call_lock(void);
 void ipi_call_unlock(void);
 void ipi_call_lock_irq(void);
 void ipi_call_unlock_irq(void);
+#else
+static inline void call_function_init(void) { }
 #endif
 
 /*
@@ -134,7 +137,7 @@ static inline void smp_send_reschedule(int cpu) { }
 #define smp_prepare_boot_cpu()                 do {} while (0)
 #define smp_call_function_many(mask, func, info, wait) \
                        (up_smp_call_function(func, info))
-static inline void init_call_single_data(void) { }
+static inline void call_function_init(void) { }
 
 static inline int
 smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
index ae045ca..1c09820 100644 (file)
@@ -20,7 +20,8 @@ struct softirq_action;
                         softirq_name(BLOCK_IOPOLL),    \
                         softirq_name(TASKLET),         \
                         softirq_name(SCHED),           \
-                        softirq_name(HRTIMER))
+                        softirq_name(HRTIMER),         \
+                        softirq_name(RCU))
 
 /**
  * irq_handler_entry - called immediately before the irq action handler
index cafba67..d7211fa 100644 (file)
@@ -542,6 +542,7 @@ asmlinkage void __init start_kernel(void)
        timekeeping_init();
        time_init();
        profile_init();
+       call_function_init();
        if (!irqs_disabled())
                printk(KERN_CRIT "start_kernel(): bug: interrupts were "
                                 "enabled early\n");
index 89419ff..7e59ffb 100644 (file)
@@ -87,6 +87,8 @@ static struct rcu_state *rcu_state;
 int rcu_scheduler_active __read_mostly;
 EXPORT_SYMBOL_GPL(rcu_scheduler_active);
 
+#ifdef CONFIG_RCU_BOOST
+
 /*
  * Control variables for per-CPU and per-rcu_node kthreads.  These
  * handle all flavors of RCU.
@@ -98,8 +100,11 @@ DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
 DEFINE_PER_CPU(char, rcu_cpu_has_work);
 static char rcu_kthreads_spawnable;
 
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
 static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu);
-static void invoke_rcu_cpu_kthread(void);
+static void invoke_rcu_core(void);
+static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp);
 
 #define RCU_KTHREAD_PRIO 1     /* RT priority for per-CPU kthreads. */
 
@@ -1088,14 +1093,8 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
        int need_report = 0;
        struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu);
        struct rcu_node *rnp;
-       struct task_struct *t;
 
-       /* Stop the CPU's kthread. */
-       t = per_cpu(rcu_cpu_kthread_task, cpu);
-       if (t != NULL) {
-               per_cpu(rcu_cpu_kthread_task, cpu) = NULL;
-               kthread_stop(t);
-       }
+       rcu_stop_cpu_kthread(cpu);
 
        /* Exclude any attempts to start a new grace period. */
        raw_spin_lock_irqsave(&rsp->onofflock, flags);
@@ -1231,7 +1230,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
 
        /* Re-raise the RCU softirq if there are callbacks remaining. */
        if (cpu_has_callbacks_ready_to_invoke(rdp))
-               invoke_rcu_cpu_kthread();
+               invoke_rcu_core();
 }
 
 /*
@@ -1277,7 +1276,7 @@ void rcu_check_callbacks(int cpu, int user)
        }
        rcu_preempt_check_callbacks(cpu);
        if (rcu_pending(cpu))
-               invoke_rcu_cpu_kthread();
+               invoke_rcu_core();
 }
 
 #ifdef CONFIG_SMP
@@ -1442,13 +1441,14 @@ __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
        }
 
        /* If there are callbacks ready, invoke them. */
-       rcu_do_batch(rsp, rdp);
+       if (cpu_has_callbacks_ready_to_invoke(rdp))
+               invoke_rcu_callbacks(rsp, rdp);
 }
 
 /*
  * Do softirq processing for the current CPU.
  */
-static void rcu_process_callbacks(void)
+static void rcu_process_callbacks(struct softirq_action *unused)
 {
        __rcu_process_callbacks(&rcu_sched_state,
                                &__get_cpu_var(rcu_sched_data));
@@ -1465,342 +1465,20 @@ static void rcu_process_callbacks(void)
  * the current CPU with interrupts disabled, the rcu_cpu_kthread_task
  * cannot disappear out from under us.
  */
-static void invoke_rcu_cpu_kthread(void)
-{
-       unsigned long flags;
-
-       local_irq_save(flags);
-       __this_cpu_write(rcu_cpu_has_work, 1);
-       if (__this_cpu_read(rcu_cpu_kthread_task) == NULL) {
-               local_irq_restore(flags);
-               return;
-       }
-       wake_up_process(__this_cpu_read(rcu_cpu_kthread_task));
-       local_irq_restore(flags);
-}
-
-/*
- * Wake up the specified per-rcu_node-structure kthread.
- * Because the per-rcu_node kthreads are immortal, we don't need
- * to do anything to keep them alive.
- */
-static void invoke_rcu_node_kthread(struct rcu_node *rnp)
-{
-       struct task_struct *t;
-
-       t = rnp->node_kthread_task;
-       if (t != NULL)
-               wake_up_process(t);
-}
-
-/*
- * Set the specified CPU's kthread to run RT or not, as specified by
- * the to_rt argument.  The CPU-hotplug locks are held, so the task
- * is not going away.
- */
-static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
-{
-       int policy;
-       struct sched_param sp;
-       struct task_struct *t;
-
-       t = per_cpu(rcu_cpu_kthread_task, cpu);
-       if (t == NULL)
-               return;
-       if (to_rt) {
-               policy = SCHED_FIFO;
-               sp.sched_priority = RCU_KTHREAD_PRIO;
-       } else {
-               policy = SCHED_NORMAL;
-               sp.sched_priority = 0;
-       }
-       sched_setscheduler_nocheck(t, policy, &sp);
-}
-
-/*
- * Timer handler to initiate the waking up of per-CPU kthreads that
- * have yielded the CPU due to excess numbers of RCU callbacks.
- * We wake up the per-rcu_node kthread, which in turn will wake up
- * the booster kthread.
- */
-static void rcu_cpu_kthread_timer(unsigned long arg)
-{
-       struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, arg);
-       struct rcu_node *rnp = rdp->mynode;
-
-       atomic_or(rdp->grpmask, &rnp->wakemask);
-       invoke_rcu_node_kthread(rnp);
-}
-
-/*
- * Drop to non-real-time priority and yield, but only after posting a
- * timer that will cause us to regain our real-time priority if we
- * remain preempted.  Either way, we restore our real-time priority
- * before returning.
- */
-static void rcu_yield(void (*f)(unsigned long), unsigned long arg)
-{
-       struct sched_param sp;
-       struct timer_list yield_timer;
-
-       setup_timer_on_stack(&yield_timer, f, arg);
-       mod_timer(&yield_timer, jiffies + 2);
-       sp.sched_priority = 0;
-       sched_setscheduler_nocheck(current, SCHED_NORMAL, &sp);
-       set_user_nice(current, 19);
-       schedule();
-       sp.sched_priority = RCU_KTHREAD_PRIO;
-       sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
-       del_timer(&yield_timer);
-}
-
-/*
- * Handle cases where the rcu_cpu_kthread() ends up on the wrong CPU.
- * This can happen while the corresponding CPU is either coming online
- * or going offline.  We cannot wait until the CPU is fully online
- * before starting the kthread, because the various notifier functions
- * can wait for RCU grace periods.  So we park rcu_cpu_kthread() until
- * the corresponding CPU is online.
- *
- * Return 1 if the kthread needs to stop, 0 otherwise.
- *
- * Caller must disable bh.  This function can momentarily enable it.
- */
-static int rcu_cpu_kthread_should_stop(int cpu)
-{
-       while (cpu_is_offline(cpu) ||
-              !cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)) ||
-              smp_processor_id() != cpu) {
-               if (kthread_should_stop())
-                       return 1;
-               per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
-               per_cpu(rcu_cpu_kthread_cpu, cpu) = raw_smp_processor_id();
-               local_bh_enable();
-               schedule_timeout_uninterruptible(1);
-               if (!cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)))
-                       set_cpus_allowed_ptr(current, cpumask_of(cpu));
-               local_bh_disable();
-       }
-       per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
-       return 0;
-}
-
-/*
- * Per-CPU kernel thread that invokes RCU callbacks.  This replaces the
- * earlier RCU softirq.
- */
-static int rcu_cpu_kthread(void *arg)
-{
-       int cpu = (int)(long)arg;
-       unsigned long flags;
-       int spincnt = 0;
-       unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu);
-       char work;
-       char *workp = &per_cpu(rcu_cpu_has_work, cpu);
-
-       for (;;) {
-               *statusp = RCU_KTHREAD_WAITING;
-               rcu_wait(*workp != 0 || kthread_should_stop());
-               local_bh_disable();
-               if (rcu_cpu_kthread_should_stop(cpu)) {
-                       local_bh_enable();
-                       break;
-               }
-               *statusp = RCU_KTHREAD_RUNNING;
-               per_cpu(rcu_cpu_kthread_loops, cpu)++;
-               local_irq_save(flags);
-               work = *workp;
-               *workp = 0;
-               local_irq_restore(flags);
-               if (work)
-                       rcu_process_callbacks();
-               local_bh_enable();
-               if (*workp != 0)
-                       spincnt++;
-               else
-                       spincnt = 0;
-               if (spincnt > 10) {
-                       *statusp = RCU_KTHREAD_YIELDING;
-                       rcu_yield(rcu_cpu_kthread_timer, (unsigned long)cpu);
-                       spincnt = 0;
-               }
-       }
-       *statusp = RCU_KTHREAD_STOPPED;
-       return 0;
-}
-
-/*
- * Spawn a per-CPU kthread, setting up affinity and priority.
- * Because the CPU hotplug lock is held, no other CPU will be attempting
- * to manipulate rcu_cpu_kthread_task.  There might be another CPU
- * attempting to access it during boot, but the locking in kthread_bind()
- * will enforce sufficient ordering.
- */
-static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
+static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
 {
-       struct sched_param sp;
-       struct task_struct *t;
-
-       if (!rcu_kthreads_spawnable ||
-           per_cpu(rcu_cpu_kthread_task, cpu) != NULL)
-               return 0;
-       t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
-       if (IS_ERR(t))
-               return PTR_ERR(t);
-       kthread_bind(t, cpu);
-       per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
-       WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL);
-       per_cpu(rcu_cpu_kthread_task, cpu) = t;
-       sp.sched_priority = RCU_KTHREAD_PRIO;
-       sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
-       return 0;
-}
-
-/*
- * Per-rcu_node kthread, which is in charge of waking up the per-CPU
- * kthreads when needed.  We ignore requests to wake up kthreads
- * for offline CPUs, which is OK because force_quiescent_state()
- * takes care of this case.
- */
-static int rcu_node_kthread(void *arg)
-{
-       int cpu;
-       unsigned long flags;
-       unsigned long mask;
-       struct rcu_node *rnp = (struct rcu_node *)arg;
-       struct sched_param sp;
-       struct task_struct *t;
-
-       for (;;) {
-               rnp->node_kthread_status = RCU_KTHREAD_WAITING;
-               rcu_wait(atomic_read(&rnp->wakemask) != 0);
-               rnp->node_kthread_status = RCU_KTHREAD_RUNNING;
-               raw_spin_lock_irqsave(&rnp->lock, flags);
-               mask = atomic_xchg(&rnp->wakemask, 0);
-               rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */
-               for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) {
-                       if ((mask & 0x1) == 0)
-                               continue;
-                       preempt_disable();
-                       t = per_cpu(rcu_cpu_kthread_task, cpu);
-                       if (!cpu_online(cpu) || t == NULL) {
-                               preempt_enable();
-                               continue;
-                       }
-                       per_cpu(rcu_cpu_has_work, cpu) = 1;
-                       sp.sched_priority = RCU_KTHREAD_PRIO;
-                       sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
-                       preempt_enable();
-               }
-       }
-       /* NOTREACHED */
-       rnp->node_kthread_status = RCU_KTHREAD_STOPPED;
-       return 0;
-}
-
-/*
- * Set the per-rcu_node kthread's affinity to cover all CPUs that are
- * served by the rcu_node in question.  The CPU hotplug lock is still
- * held, so the value of rnp->qsmaskinit will be stable.
- *
- * We don't include outgoingcpu in the affinity set, use -1 if there is
- * no outgoing CPU.  If there are no CPUs left in the affinity set,
- * this function allows the kthread to execute on any CPU.
- */
-static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
-{
-       cpumask_var_t cm;
-       int cpu;
-       unsigned long mask = rnp->qsmaskinit;
-
-       if (rnp->node_kthread_task == NULL)
-               return;
-       if (!alloc_cpumask_var(&cm, GFP_KERNEL))
+       if (likely(!rsp->boost)) {
+               rcu_do_batch(rsp, rdp);
                return;
-       cpumask_clear(cm);
-       for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1)
-               if ((mask & 0x1) && cpu != outgoingcpu)
-                       cpumask_set_cpu(cpu, cm);
-       if (cpumask_weight(cm) == 0) {
-               cpumask_setall(cm);
-               for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++)
-                       cpumask_clear_cpu(cpu, cm);
-               WARN_ON_ONCE(cpumask_weight(cm) == 0);
        }
-       set_cpus_allowed_ptr(rnp->node_kthread_task, cm);
-       rcu_boost_kthread_setaffinity(rnp, cm);
-       free_cpumask_var(cm);
+       invoke_rcu_callbacks_kthread();
 }
 
-/*
- * Spawn a per-rcu_node kthread, setting priority and affinity.
- * Called during boot before online/offline can happen, or, if
- * during runtime, with the main CPU-hotplug locks held.  So only
- * one of these can be executing at a time.
- */
-static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
-                                               struct rcu_node *rnp)
+static void invoke_rcu_core(void)
 {
-       unsigned long flags;
-       int rnp_index = rnp - &rsp->node[0];
-       struct sched_param sp;
-       struct task_struct *t;
-
-       if (!rcu_kthreads_spawnable ||
-           rnp->qsmaskinit == 0)
-               return 0;
-       if (rnp->node_kthread_task == NULL) {
-               t = kthread_create(rcu_node_kthread, (void *)rnp,
-                                  "rcun%d", rnp_index);
-               if (IS_ERR(t))
-                       return PTR_ERR(t);
-               raw_spin_lock_irqsave(&rnp->lock, flags);
-               rnp->node_kthread_task = t;
-               raw_spin_unlock_irqrestore(&rnp->lock, flags);
-               sp.sched_priority = 99;
-               sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
-       }
-       return rcu_spawn_one_boost_kthread(rsp, rnp, rnp_index);
+       raise_softirq(RCU_SOFTIRQ);
 }
 
-static void rcu_wake_one_boost_kthread(struct rcu_node *rnp);
-
-/*
- * Spawn all kthreads -- called as soon as the scheduler is running.
- */
-static int __init rcu_spawn_kthreads(void)
-{
-       int cpu;
-       struct rcu_node *rnp;
-       struct task_struct *t;
-
-       rcu_kthreads_spawnable = 1;
-       for_each_possible_cpu(cpu) {
-               per_cpu(rcu_cpu_has_work, cpu) = 0;
-               if (cpu_online(cpu)) {
-                       (void)rcu_spawn_one_cpu_kthread(cpu);
-                       t = per_cpu(rcu_cpu_kthread_task, cpu);
-                       if (t)
-                               wake_up_process(t);
-               }
-       }
-       rnp = rcu_get_root(rcu_state);
-       (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
-       if (rnp->node_kthread_task)
-               wake_up_process(rnp->node_kthread_task);
-       if (NUM_RCU_NODES > 1) {
-               rcu_for_each_leaf_node(rcu_state, rnp) {
-                       (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
-                       t = rnp->node_kthread_task;
-                       if (t)
-                               wake_up_process(t);
-                       rcu_wake_one_boost_kthread(rnp);
-               }
-       }
-       return 0;
-}
-early_initcall(rcu_spawn_kthreads);
-
 static void
 __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
           struct rcu_state *rsp)
@@ -2207,44 +1885,6 @@ static void __cpuinit rcu_prepare_cpu(int cpu)
        rcu_preempt_init_percpu_data(cpu);
 }
 
-static void __cpuinit rcu_prepare_kthreads(int cpu)
-{
-       struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
-       struct rcu_node *rnp = rdp->mynode;
-
-       /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */
-       if (rcu_kthreads_spawnable) {
-               (void)rcu_spawn_one_cpu_kthread(cpu);
-               if (rnp->node_kthread_task == NULL)
-                       (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
-       }
-}
-
-/*
- * kthread_create() creates threads in TASK_UNINTERRUPTIBLE state,
- * but the RCU threads are woken on demand, and if demand is low this
- * could be a while triggering the hung task watchdog.
- *
- * In order to avoid this, poke all tasks once the CPU is fully
- * up and running.
- */
-static void __cpuinit rcu_online_kthreads(int cpu)
-{
-       struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
-       struct rcu_node *rnp = rdp->mynode;
-       struct task_struct *t;
-
-       t = per_cpu(rcu_cpu_kthread_task, cpu);
-       if (t)
-               wake_up_process(t);
-
-       t = rnp->node_kthread_task;
-       if (t)
-               wake_up_process(t);
-
-       rcu_wake_one_boost_kthread(rnp);
-}
-
 /*
  * Handle CPU online/offline notification events.
  */
@@ -2262,7 +1902,6 @@ static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
                rcu_prepare_kthreads(cpu);
                break;
        case CPU_ONLINE:
-               rcu_online_kthreads(cpu);
        case CPU_DOWN_FAILED:
                rcu_node_kthread_setaffinity(rnp, -1);
                rcu_cpu_kthread_setrt(cpu, 1);
@@ -2410,6 +2049,7 @@ void __init rcu_init(void)
        rcu_init_one(&rcu_sched_state, &rcu_sched_data);
        rcu_init_one(&rcu_bh_state, &rcu_bh_data);
        __rcu_init_preempt();
+        open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
 
        /*
         * We don't need protection against CPU-hotplug here because
index 7b9a08b..01b2ccd 100644 (file)
@@ -369,6 +369,7 @@ struct rcu_state {
                                                /*  period because */
                                                /*  force_quiescent_state() */
                                                /*  was running. */
+       u8      boost;                          /* Subject to priority boost. */
        unsigned long gpnum;                    /* Current gp number. */
        unsigned long completed;                /* # of last completed gp. */
 
@@ -426,6 +427,7 @@ static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
 #ifdef CONFIG_HOTPLUG_CPU
 static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,
                                      unsigned long flags);
+static void rcu_stop_cpu_kthread(int cpu);
 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
 static void rcu_print_detail_task_stall(struct rcu_state *rsp);
 static void rcu_print_task_stall(struct rcu_node *rnp);
@@ -450,11 +452,19 @@ static void rcu_preempt_send_cbs_to_online(void);
 static void __init __rcu_init_preempt(void);
 static void rcu_needs_cpu_flush(void);
 static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
+static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
+static void invoke_rcu_callbacks_kthread(void);
+#ifdef CONFIG_RCU_BOOST
+static void rcu_preempt_do_callbacks(void);
 static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
                                          cpumask_var_t cm);
-static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
 static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
                                                 struct rcu_node *rnp,
                                                 int rnp_index);
+static void invoke_rcu_node_kthread(struct rcu_node *rnp);
+static void rcu_yield(void (*f)(unsigned long), unsigned long arg);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt);
+static void __cpuinit rcu_prepare_kthreads(int cpu);
 
 #endif /* #ifndef RCU_TREE_NONCORE */
index c8bff30..14dc7dd 100644 (file)
@@ -602,6 +602,15 @@ static void rcu_preempt_process_callbacks(void)
                                &__get_cpu_var(rcu_preempt_data));
 }
 
+#ifdef CONFIG_RCU_BOOST
+
+static void rcu_preempt_do_callbacks(void)
+{
+       rcu_do_batch(&rcu_preempt_state, &__get_cpu_var(rcu_preempt_data));
+}
+
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
 /*
  * Queue a preemptible-RCU callback for invocation after a grace period.
  */
@@ -1248,6 +1257,23 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
        }
 }
 
+/*
+ * Wake up the per-CPU kthread to invoke RCU callbacks.
+ */
+static void invoke_rcu_callbacks_kthread(void)
+{
+       unsigned long flags;
+
+       local_irq_save(flags);
+       __this_cpu_write(rcu_cpu_has_work, 1);
+       if (__this_cpu_read(rcu_cpu_kthread_task) == NULL) {
+               local_irq_restore(flags);
+               return;
+       }
+       wake_up_process(__this_cpu_read(rcu_cpu_kthread_task));
+       local_irq_restore(flags);
+}
+
 /*
  * Set the affinity of the boost kthread.  The CPU-hotplug locks are
  * held, so no one should be messing with the existence of the boost
@@ -1288,6 +1314,7 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
 
        if (&rcu_preempt_state != rsp)
                return 0;
+       rsp->boost = 1;
        if (rnp->boost_kthread_task != NULL)
                return 0;
        t = kthread_create(rcu_boost_kthread, (void *)rnp,
@@ -1299,13 +1326,372 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
        raw_spin_unlock_irqrestore(&rnp->lock, flags);
        sp.sched_priority = RCU_KTHREAD_PRIO;
        sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+       wake_up_process(t); /* get to TASK_INTERRUPTIBLE quickly. */
        return 0;
 }
 
-static void __cpuinit rcu_wake_one_boost_kthread(struct rcu_node *rnp)
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Stop the RCU's per-CPU kthread when its CPU goes offline,.
+ */
+static void rcu_stop_cpu_kthread(int cpu)
 {
-       if (rnp->boost_kthread_task)
-               wake_up_process(rnp->boost_kthread_task);
+       struct task_struct *t;
+
+       /* Stop the CPU's kthread. */
+       t = per_cpu(rcu_cpu_kthread_task, cpu);
+       if (t != NULL) {
+               per_cpu(rcu_cpu_kthread_task, cpu) = NULL;
+               kthread_stop(t);
+       }
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+static void rcu_kthread_do_work(void)
+{
+       rcu_do_batch(&rcu_sched_state, &__get_cpu_var(rcu_sched_data));
+       rcu_do_batch(&rcu_bh_state, &__get_cpu_var(rcu_bh_data));
+       rcu_preempt_do_callbacks();
+}
+
+/*
+ * Wake up the specified per-rcu_node-structure kthread.
+ * Because the per-rcu_node kthreads are immortal, we don't need
+ * to do anything to keep them alive.
+ */
+static void invoke_rcu_node_kthread(struct rcu_node *rnp)
+{
+       struct task_struct *t;
+
+       t = rnp->node_kthread_task;
+       if (t != NULL)
+               wake_up_process(t);
+}
+
+/*
+ * Set the specified CPU's kthread to run RT or not, as specified by
+ * the to_rt argument.  The CPU-hotplug locks are held, so the task
+ * is not going away.
+ */
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
+{
+       int policy;
+       struct sched_param sp;
+       struct task_struct *t;
+
+       t = per_cpu(rcu_cpu_kthread_task, cpu);
+       if (t == NULL)
+               return;
+       if (to_rt) {
+               policy = SCHED_FIFO;
+               sp.sched_priority = RCU_KTHREAD_PRIO;
+       } else {
+               policy = SCHED_NORMAL;
+               sp.sched_priority = 0;
+       }
+       sched_setscheduler_nocheck(t, policy, &sp);
+}
+
+/*
+ * Timer handler to initiate the waking up of per-CPU kthreads that
+ * have yielded the CPU due to excess numbers of RCU callbacks.
+ * We wake up the per-rcu_node kthread, which in turn will wake up
+ * the booster kthread.
+ */
+static void rcu_cpu_kthread_timer(unsigned long arg)
+{
+       struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, arg);
+       struct rcu_node *rnp = rdp->mynode;
+
+       atomic_or(rdp->grpmask, &rnp->wakemask);
+       invoke_rcu_node_kthread(rnp);
+}
+
+/*
+ * Drop to non-real-time priority and yield, but only after posting a
+ * timer that will cause us to regain our real-time priority if we
+ * remain preempted.  Either way, we restore our real-time priority
+ * before returning.
+ */
+static void rcu_yield(void (*f)(unsigned long), unsigned long arg)
+{
+       struct sched_param sp;
+       struct timer_list yield_timer;
+
+       setup_timer_on_stack(&yield_timer, f, arg);
+       mod_timer(&yield_timer, jiffies + 2);
+       sp.sched_priority = 0;
+       sched_setscheduler_nocheck(current, SCHED_NORMAL, &sp);
+       set_user_nice(current, 19);
+       schedule();
+       sp.sched_priority = RCU_KTHREAD_PRIO;
+       sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
+       del_timer(&yield_timer);
+}
+
+/*
+ * Handle cases where the rcu_cpu_kthread() ends up on the wrong CPU.
+ * This can happen while the corresponding CPU is either coming online
+ * or going offline.  We cannot wait until the CPU is fully online
+ * before starting the kthread, because the various notifier functions
+ * can wait for RCU grace periods.  So we park rcu_cpu_kthread() until
+ * the corresponding CPU is online.
+ *
+ * Return 1 if the kthread needs to stop, 0 otherwise.
+ *
+ * Caller must disable bh.  This function can momentarily enable it.
+ */
+static int rcu_cpu_kthread_should_stop(int cpu)
+{
+       while (cpu_is_offline(cpu) ||
+              !cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)) ||
+              smp_processor_id() != cpu) {
+               if (kthread_should_stop())
+                       return 1;
+               per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
+               per_cpu(rcu_cpu_kthread_cpu, cpu) = raw_smp_processor_id();
+               local_bh_enable();
+               schedule_timeout_uninterruptible(1);
+               if (!cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)))
+                       set_cpus_allowed_ptr(current, cpumask_of(cpu));
+               local_bh_disable();
+       }
+       per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
+       return 0;
+}
+
+/*
+ * Per-CPU kernel thread that invokes RCU callbacks.  This replaces the
+ * earlier RCU softirq.
+ */
+static int rcu_cpu_kthread(void *arg)
+{
+       int cpu = (int)(long)arg;
+       unsigned long flags;
+       int spincnt = 0;
+       unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu);
+       char work;
+       char *workp = &per_cpu(rcu_cpu_has_work, cpu);
+
+       for (;;) {
+               *statusp = RCU_KTHREAD_WAITING;
+               rcu_wait(*workp != 0 || kthread_should_stop());
+               local_bh_disable();
+               if (rcu_cpu_kthread_should_stop(cpu)) {
+                       local_bh_enable();
+                       break;
+               }
+               *statusp = RCU_KTHREAD_RUNNING;
+               per_cpu(rcu_cpu_kthread_loops, cpu)++;
+               local_irq_save(flags);
+               work = *workp;
+               *workp = 0;
+               local_irq_restore(flags);
+               if (work)
+                       rcu_kthread_do_work();
+               local_bh_enable();
+               if (*workp != 0)
+                       spincnt++;
+               else
+                       spincnt = 0;
+               if (spincnt > 10) {
+                       *statusp = RCU_KTHREAD_YIELDING;
+                       rcu_yield(rcu_cpu_kthread_timer, (unsigned long)cpu);
+                       spincnt = 0;
+               }
+       }
+       *statusp = RCU_KTHREAD_STOPPED;
+       return 0;
+}
+
+/*
+ * Spawn a per-CPU kthread, setting up affinity and priority.
+ * Because the CPU hotplug lock is held, no other CPU will be attempting
+ * to manipulate rcu_cpu_kthread_task.  There might be another CPU
+ * attempting to access it during boot, but the locking in kthread_bind()
+ * will enforce sufficient ordering.
+ *
+ * Please note that we cannot simply refuse to wake up the per-CPU
+ * kthread because kthreads are created in TASK_UNINTERRUPTIBLE state,
+ * which can result in softlockup complaints if the task ends up being
+ * idle for more than a couple of minutes.
+ *
+ * However, please note also that we cannot bind the per-CPU kthread to its
+ * CPU until that CPU is fully online.  We also cannot wait until the
+ * CPU is fully online before we create its per-CPU kthread, as this would
+ * deadlock the system when CPU notifiers tried waiting for grace
+ * periods.  So we bind the per-CPU kthread to its CPU only if the CPU
+ * is online.  If its CPU is not yet fully online, then the code in
+ * rcu_cpu_kthread() will wait until it is fully online, and then do
+ * the binding.
+ */
+static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
+{
+       struct sched_param sp;
+       struct task_struct *t;
+
+       if (!rcu_kthreads_spawnable ||
+           per_cpu(rcu_cpu_kthread_task, cpu) != NULL)
+               return 0;
+       t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
+       if (IS_ERR(t))
+               return PTR_ERR(t);
+       if (cpu_online(cpu))
+               kthread_bind(t, cpu);
+       per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
+       WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL);
+       sp.sched_priority = RCU_KTHREAD_PRIO;
+       sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+       per_cpu(rcu_cpu_kthread_task, cpu) = t;
+       wake_up_process(t); /* Get to TASK_INTERRUPTIBLE quickly. */
+       return 0;
+}
+
+/*
+ * Per-rcu_node kthread, which is in charge of waking up the per-CPU
+ * kthreads when needed.  We ignore requests to wake up kthreads
+ * for offline CPUs, which is OK because force_quiescent_state()
+ * takes care of this case.
+ */
+static int rcu_node_kthread(void *arg)
+{
+       int cpu;
+       unsigned long flags;
+       unsigned long mask;
+       struct rcu_node *rnp = (struct rcu_node *)arg;
+       struct sched_param sp;
+       struct task_struct *t;
+
+       for (;;) {
+               rnp->node_kthread_status = RCU_KTHREAD_WAITING;
+               rcu_wait(atomic_read(&rnp->wakemask) != 0);
+               rnp->node_kthread_status = RCU_KTHREAD_RUNNING;
+               raw_spin_lock_irqsave(&rnp->lock, flags);
+               mask = atomic_xchg(&rnp->wakemask, 0);
+               rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */
+               for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) {
+                       if ((mask & 0x1) == 0)
+                               continue;
+                       preempt_disable();
+                       t = per_cpu(rcu_cpu_kthread_task, cpu);
+                       if (!cpu_online(cpu) || t == NULL) {
+                               preempt_enable();
+                               continue;
+                       }
+                       per_cpu(rcu_cpu_has_work, cpu) = 1;
+                       sp.sched_priority = RCU_KTHREAD_PRIO;
+                       sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+                       preempt_enable();
+               }
+       }
+       /* NOTREACHED */
+       rnp->node_kthread_status = RCU_KTHREAD_STOPPED;
+       return 0;
+}
+
+/*
+ * Set the per-rcu_node kthread's affinity to cover all CPUs that are
+ * served by the rcu_node in question.  The CPU hotplug lock is still
+ * held, so the value of rnp->qsmaskinit will be stable.
+ *
+ * We don't include outgoingcpu in the affinity set, use -1 if there is
+ * no outgoing CPU.  If there are no CPUs left in the affinity set,
+ * this function allows the kthread to execute on any CPU.
+ */
+static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
+{
+       cpumask_var_t cm;
+       int cpu;
+       unsigned long mask = rnp->qsmaskinit;
+
+       if (rnp->node_kthread_task == NULL)
+               return;
+       if (!alloc_cpumask_var(&cm, GFP_KERNEL))
+               return;
+       cpumask_clear(cm);
+       for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1)
+               if ((mask & 0x1) && cpu != outgoingcpu)
+                       cpumask_set_cpu(cpu, cm);
+       if (cpumask_weight(cm) == 0) {
+               cpumask_setall(cm);
+               for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++)
+                       cpumask_clear_cpu(cpu, cm);
+               WARN_ON_ONCE(cpumask_weight(cm) == 0);
+       }
+       set_cpus_allowed_ptr(rnp->node_kthread_task, cm);
+       rcu_boost_kthread_setaffinity(rnp, cm);
+       free_cpumask_var(cm);
+}
+
+/*
+ * Spawn a per-rcu_node kthread, setting priority and affinity.
+ * Called during boot before online/offline can happen, or, if
+ * during runtime, with the main CPU-hotplug locks held.  So only
+ * one of these can be executing at a time.
+ */
+static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
+                                               struct rcu_node *rnp)
+{
+       unsigned long flags;
+       int rnp_index = rnp - &rsp->node[0];
+       struct sched_param sp;
+       struct task_struct *t;
+
+       if (!rcu_kthreads_spawnable ||
+           rnp->qsmaskinit == 0)
+               return 0;
+       if (rnp->node_kthread_task == NULL) {
+               t = kthread_create(rcu_node_kthread, (void *)rnp,
+                                  "rcun%d", rnp_index);
+               if (IS_ERR(t))
+                       return PTR_ERR(t);
+               raw_spin_lock_irqsave(&rnp->lock, flags);
+               rnp->node_kthread_task = t;
+               raw_spin_unlock_irqrestore(&rnp->lock, flags);
+               sp.sched_priority = 99;
+               sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+               wake_up_process(t); /* get to TASK_INTERRUPTIBLE quickly. */
+       }
+       return rcu_spawn_one_boost_kthread(rsp, rnp, rnp_index);
+}
+
+/*
+ * Spawn all kthreads -- called as soon as the scheduler is running.
+ */
+static int __init rcu_spawn_kthreads(void)
+{
+       int cpu;
+       struct rcu_node *rnp;
+
+       rcu_kthreads_spawnable = 1;
+       for_each_possible_cpu(cpu) {
+               per_cpu(rcu_cpu_has_work, cpu) = 0;
+               if (cpu_online(cpu))
+                       (void)rcu_spawn_one_cpu_kthread(cpu);
+       }
+       rnp = rcu_get_root(rcu_state);
+       (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+       if (NUM_RCU_NODES > 1) {
+               rcu_for_each_leaf_node(rcu_state, rnp)
+                       (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+       }
+       return 0;
+}
+early_initcall(rcu_spawn_kthreads);
+
+static void __cpuinit rcu_prepare_kthreads(int cpu)
+{
+       struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
+       struct rcu_node *rnp = rdp->mynode;
+
+       /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */
+       if (rcu_kthreads_spawnable) {
+               (void)rcu_spawn_one_cpu_kthread(cpu);
+               if (rnp->node_kthread_task == NULL)
+                       (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+       }
 }
 
 #else /* #ifdef CONFIG_RCU_BOOST */
@@ -1315,23 +1701,32 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
        raw_spin_unlock_irqrestore(&rnp->lock, flags);
 }
 
-static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
-                                         cpumask_var_t cm)
+static void invoke_rcu_callbacks_kthread(void)
 {
+       WARN_ON_ONCE(1);
 }
 
 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
 {
 }
 
-static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
-                                                struct rcu_node *rnp,
-                                                int rnp_index)
+#ifdef CONFIG_HOTPLUG_CPU
+
+static void rcu_stop_cpu_kthread(int cpu)
+{
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
+{
+}
+
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
 {
-       return 0;
 }
 
-static void __cpuinit rcu_wake_one_boost_kthread(struct rcu_node *rnp)
+static void __cpuinit rcu_prepare_kthreads(int cpu)
 {
 }
 
@@ -1509,7 +1904,7 @@ static DEFINE_PER_CPU(unsigned long, rcu_dyntick_holdoff);
  *
  * Because it is not legal to invoke rcu_process_callbacks() with irqs
  * disabled, we do one pass of force_quiescent_state(), then do a
- * invoke_rcu_cpu_kthread() to cause rcu_process_callbacks() to be invoked
+ * invoke_rcu_core() to cause rcu_process_callbacks() to be invoked
  * later.  The per-cpu rcu_dyntick_drain variable controls the sequencing.
  */
 int rcu_needs_cpu(int cpu)
@@ -1560,7 +1955,7 @@ int rcu_needs_cpu(int cpu)
 
        /* If RCU callbacks are still pending, RCU still needs this CPU. */
        if (c)
-               invoke_rcu_cpu_kthread();
+               invoke_rcu_core();
        return c;
 }
 
index 9678cc3..4e14487 100644 (file)
@@ -46,6 +46,8 @@
 #define RCU_TREE_NONCORE
 #include "rcutree.h"
 
+#ifdef CONFIG_RCU_BOOST
+
 DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
 DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_cpu);
 DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
@@ -58,6 +60,8 @@ static char convert_kthread_status(unsigned int kthread_status)
        return "SRWOY"[kthread_status];
 }
 
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
 static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
 {
        if (!rdp->beenonline)
@@ -76,7 +80,7 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
                   rdp->dynticks_fqs);
 #endif /* #ifdef CONFIG_NO_HZ */
        seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
-       seq_printf(m, " ql=%ld qs=%c%c%c%c kt=%d/%c/%d ktl=%x b=%ld",
+       seq_printf(m, " ql=%ld qs=%c%c%c%c",
                   rdp->qlen,
                   ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
                        rdp->nxttail[RCU_NEXT_TAIL]],
@@ -84,13 +88,16 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
                        rdp->nxttail[RCU_NEXT_READY_TAIL]],
                   ".W"[rdp->nxttail[RCU_DONE_TAIL] !=
                        rdp->nxttail[RCU_WAIT_TAIL]],
-                  ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]],
+                  ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
+#ifdef CONFIG_RCU_BOOST
+       seq_printf(m, " kt=%d/%c/%d ktl=%x",
                   per_cpu(rcu_cpu_has_work, rdp->cpu),
                   convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
                                          rdp->cpu)),
                   per_cpu(rcu_cpu_kthread_cpu, rdp->cpu),
-                  per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff,
-                  rdp->blimit);
+                  per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+       seq_printf(m, " b=%ld", rdp->blimit);
        seq_printf(m, " ci=%lu co=%lu ca=%lu\n",
                   rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
 }
@@ -147,18 +154,21 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
                   rdp->dynticks_fqs);
 #endif /* #ifdef CONFIG_NO_HZ */
        seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
-       seq_printf(m, ",%ld,\"%c%c%c%c\",%d,\"%c\",%ld", rdp->qlen,
+       seq_printf(m, ",%ld,\"%c%c%c%c\"", rdp->qlen,
                   ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
                        rdp->nxttail[RCU_NEXT_TAIL]],
                   ".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
                        rdp->nxttail[RCU_NEXT_READY_TAIL]],
                   ".W"[rdp->nxttail[RCU_DONE_TAIL] !=
                        rdp->nxttail[RCU_WAIT_TAIL]],
-                  ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]],
+                  ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
+#ifdef CONFIG_RCU_BOOST
+       seq_printf(m, ",%d,\"%c\"",
                   per_cpu(rcu_cpu_has_work, rdp->cpu),
                   convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
-                                         rdp->cpu)),
-                  rdp->blimit);
+                                         rdp->cpu)));
+#endif /* #ifdef CONFIG_RCU_BOOST */
+       seq_printf(m, ",%ld", rdp->blimit);
        seq_printf(m, ",%lu,%lu,%lu\n",
                   rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
 }
@@ -169,7 +179,11 @@ static int show_rcudata_csv(struct seq_file *m, void *unused)
 #ifdef CONFIG_NO_HZ
        seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
 #endif /* #ifdef CONFIG_NO_HZ */
-       seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\",\"ci\",\"co\",\"ca\"\n");
+       seq_puts(m, "\"of\",\"ri\",\"ql\",\"qs\"");
+#ifdef CONFIG_RCU_BOOST
+       seq_puts(m, "\"kt\",\"ktl\"");
+#endif /* #ifdef CONFIG_RCU_BOOST */
+       seq_puts(m, ",\"b\",\"ci\",\"co\",\"ca\"\n");
 #ifdef CONFIG_TREE_PREEMPT_RCU
        seq_puts(m, "\"rcu_preempt:\"\n");
        PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data_csv, m);
index 73a1951..fb67dfa 100644 (file)
@@ -74,7 +74,7 @@ static struct notifier_block __cpuinitdata hotplug_cfd_notifier = {
        .notifier_call          = hotplug_cfd,
 };
 
-static int __cpuinit init_call_single_data(void)
+void __init call_function_init(void)
 {
        void *cpu = (void *)(long)smp_processor_id();
        int i;
@@ -88,10 +88,7 @@ static int __cpuinit init_call_single_data(void)
 
        hotplug_cfd(&hotplug_cfd_notifier, CPU_UP_PREPARE, cpu);
        register_cpu_notifier(&hotplug_cfd_notifier);
-
-       return 0;
 }
-early_initcall(init_call_single_data);
 
 /*
  * csd_lock/csd_unlock used to serialize access to per-cpu csd resources
index 1396017..40cf63d 100644 (file)
@@ -58,7 +58,7 @@ DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
 
 char *softirq_to_name[NR_SOFTIRQS] = {
        "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL",
-       "TASKLET", "SCHED", "HRTIMER"
+       "TASKLET", "SCHED", "HRTIMER", "RCU"
 };
 
 /*
index 1c95fd6..e0980f0 100644 (file)
@@ -185,7 +185,6 @@ static struct clocksource *watchdog;
 static struct timer_list watchdog_timer;
 static DECLARE_WORK(watchdog_work, clocksource_watchdog_work);
 static DEFINE_SPINLOCK(watchdog_lock);
-static cycle_t watchdog_last;
 static int watchdog_running;
 
 static int clocksource_watchdog_kthread(void *data);
@@ -254,11 +253,6 @@ static void clocksource_watchdog(unsigned long data)
        if (!watchdog_running)
                goto out;
 
-       wdnow = watchdog->read(watchdog);
-       wd_nsec = clocksource_cyc2ns((wdnow - watchdog_last) & watchdog->mask,
-                                    watchdog->mult, watchdog->shift);
-       watchdog_last = wdnow;
-
        list_for_each_entry(cs, &watchdog_list, wd_list) {
 
                /* Clocksource already marked unstable? */
@@ -268,19 +262,28 @@ static void clocksource_watchdog(unsigned long data)
                        continue;
                }
 
+               local_irq_disable();
                csnow = cs->read(cs);
+               wdnow = watchdog->read(watchdog);
+               local_irq_enable();
 
                /* Clocksource initialized ? */
                if (!(cs->flags & CLOCK_SOURCE_WATCHDOG)) {
                        cs->flags |= CLOCK_SOURCE_WATCHDOG;
-                       cs->wd_last = csnow;
+                       cs->wd_last = wdnow;
+                       cs->cs_last = csnow;
                        continue;
                }
 
-               /* Check the deviation from the watchdog clocksource. */
-               cs_nsec = clocksource_cyc2ns((csnow - cs->wd_last) &
+               wd_nsec = clocksource_cyc2ns((wdnow - cs->wd_last) & watchdog->mask,
+                                            watchdog->mult, watchdog->shift);
+
+               cs_nsec = clocksource_cyc2ns((csnow - cs->cs_last) &
                                             cs->mask, cs->mult, cs->shift);
-               cs->wd_last = csnow;
+               cs->cs_last = csnow;
+               cs->wd_last = wdnow;
+
+               /* Check the deviation from the watchdog clocksource. */
                if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) {
                        clocksource_unstable(cs, cs_nsec - wd_nsec);
                        continue;
@@ -318,7 +321,6 @@ static inline void clocksource_start_watchdog(void)
                return;
        init_timer(&watchdog_timer);
        watchdog_timer.function = clocksource_watchdog;
-       watchdog_last = watchdog->read(watchdog);
        watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL;
        add_timer_on(&watchdog_timer, cpumask_first(cpu_online_mask));
        watchdog_running = 1;
index dff763b..1f06468 100644 (file)
@@ -240,13 +240,10 @@ static const char **find_next(void *v, loff_t *pos)
        const char **fmt = v;
        int start_index;
 
-       if (!fmt)
-               fmt = __start___trace_bprintk_fmt + *pos;
-
        start_index = __stop___trace_bprintk_fmt - __start___trace_bprintk_fmt;
 
        if (*pos < start_index)
-               return fmt;
+               return __start___trace_bprintk_fmt + *pos;
 
        return find_next_mod_format(start_index, v, fmt, pos);
 }
index 032ba63..940257b 100644 (file)
@@ -633,7 +633,7 @@ prefix_SQ = $(subst ','\'',$(prefix))
 
 SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
 
-LIBS = -Wl,--whole-archive $(PERFLIBS) -Wl,--no-whole-archive $(EXTLIBS)
+LIBS = -Wl,--whole-archive $(PERFLIBS) -Wl,--no-whole-archive -Wl,--start-group $(EXTLIBS) -Wl,--end-group
 
 ALL_CFLAGS += $(BASIC_CFLAGS)
 ALL_CFLAGS += $(ARCH_CFLAGS)
index 1e88485..0a7ed5b 100644 (file)
@@ -2187,6 +2187,7 @@ static const struct flag flags[] = {
        { "TASKLET_SOFTIRQ", 6 },
        { "SCHED_SOFTIRQ", 7 },
        { "HRTIMER_SOFTIRQ", 8 },
+       { "RCU_SOFTIRQ", 9 },
 
        { "HRTIMER_NORESTART", 0 },
        { "HRTIMER_RESTART", 1 },