Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sparc64: Fix cpumask related build failure
  smp_call_function_single(): be slightly less stupid, fix
  smp_call_function_single(): be slightly less stupid
  rcu: fix bug in rcutorture system-shutdown code

diff --git a/arch/sparc/include/asm/topology_64.h b/arch/sparc/include/asm/topology_64.h
index b8a65b64e1dfc3275c41f33d74c993ba527e5843..5bc0b8fd63744f477f7ade478e42922175649c28 100644 (file)
--- a/arch/sparc/include/asm/topology_64.h
+++ b/arch/sparc/include/asm/topology_64.h
@@ -47,6 +47,10 @@ static inline int pcibus_to_node(struct pci_bus *pbus)
        (pcibus_to_node(bus) == -1 ? \
         CPU_MASK_ALL : \
         node_to_cpumask(pcibus_to_node(bus)))
+#define cpumask_of_pcibus(bus) \
+       (pcibus_to_node(bus) == -1 ? \
+        CPU_MASK_ALL_PTR : \
+        cpumask_of_node(pcibus_to_node(bus)))
 
 #define SD_NODE_INIT (struct sched_domain) {           \
        .min_interval           = 8,                    \

diff --git a/include/linux/smp.h b/include/linux/smp.h
index b824669681014502e1f1d0972ad5d9f775d274cb..715196b09d6714ff971ddd95c839225d81810666 100644 (file)
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -24,6 +24,9 @@ struct call_single_data {
 /* total number of cpus in this system (may exceed NR_CPUS) */
 extern unsigned int total_cpus;
 
+int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
+                               int wait);
+
 #ifdef CONFIG_SMP
 
 #include <linux/preempt.h>
@@ -79,8 +82,6 @@ smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
        return 0;
 }
 
-int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
-                               int wait);
 void __smp_call_function_single(int cpuid, struct call_single_data *data);
 
 /*
@@ -140,14 +141,6 @@ static inline int up_smp_call_function(void (*func)(void *), void *info)
 static inline void smp_send_reschedule(int cpu) { }
 #define num_booting_cpus()                     1
 #define smp_prepare_boot_cpu()                 do {} while (0)
-#define smp_call_function_single(cpuid, func, info, wait) \
-({ \
-       WARN_ON(cpuid != 0);    \
-       local_irq_disable();    \
-       (func)(info);           \
-       local_irq_enable();     \
-       0;                      \
-})
 #define smp_call_function_mask(mask, func, info, wait) \
                        (up_smp_call_function(func, info))
 #define smp_call_function_many(mask, func, info, wait) \

diff --git a/kernel/Makefile b/kernel/Makefile
index 2921d90ce32fd760000622032f6569b5ab413d71..2aebc4cd787810a5e71ca4ea4aa35301220a6355 100644 (file)
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -40,7 +40,11 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
 obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
 obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o
 obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
-obj-$(CONFIG_USE_GENERIC_SMP_HELPERS) += smp.o
+ifeq ($(CONFIG_USE_GENERIC_SMP_HELPERS),y)
+obj-y += smp.o
+else
+obj-y += up.o
+endif
 obj-$(CONFIG_SMP) += spinlock.o
 obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
 obj-$(CONFIG_PROVE_LOCKING) += spinlock.o

diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 1cff28db56b6a87cacc225a740e602c4603d2e50..7c4142a79f0ab5a2ef80300b3d5be3188bdec8c7 100644 (file)
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -136,28 +136,46 @@ static int stutter_pause_test = 0;
 #endif
 int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT;
 
-#define FULLSTOP_SHUTDOWN 1    /* Bail due to system shutdown/panic. */
-#define FULLSTOP_CLEANUP  2    /* Orderly shutdown. */
-static int fullstop;           /* stop generating callbacks at test end. */
-DEFINE_MUTEX(fullstop_mutex);  /* protect fullstop transitions and */
-                               /*  spawning of kthreads. */
+/* Mediate rmmod and system shutdown.  Concurrent rmmod & shutdown illegal! */
+
+#define FULLSTOP_DONTSTOP 0    /* Normal operation. */
+#define FULLSTOP_SHUTDOWN 1    /* System shutdown with rcutorture running. */
+#define FULLSTOP_RMMOD    2    /* Normal rmmod of rcutorture. */
+static int fullstop = FULLSTOP_RMMOD;
+DEFINE_MUTEX(fullstop_mutex);  /* Protect fullstop transitions and spawning */
+                               /*  of kthreads. */
 
 /*
- * Detect and respond to a signal-based shutdown.
+ * Detect and respond to a system shutdown.
  */
 static int
 rcutorture_shutdown_notify(struct notifier_block *unused1,
                           unsigned long unused2, void *unused3)
 {
-       if (fullstop)
-               return NOTIFY_DONE;
        mutex_lock(&fullstop_mutex);
-       if (!fullstop)
+       if (fullstop == FULLSTOP_DONTSTOP)
                fullstop = FULLSTOP_SHUTDOWN;
+       else
+               printk(KERN_WARNING /* but going down anyway, so... */
+                      "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
        mutex_unlock(&fullstop_mutex);
        return NOTIFY_DONE;
 }
 
+/*
+ * Absorb kthreads into a kernel function that won't return, so that
+ * they won't ever access module text or data again.
+ */
+static void rcutorture_shutdown_absorb(char *title)
+{
+       if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+               printk(KERN_NOTICE
+                      "rcutorture thread %s parking due to system shutdown\n",
+                      title);
+               schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
+       }
+}
+
 /*
  * Allocate an element from the rcu_tortures pool.
  */
@@ -219,13 +237,14 @@ rcu_random(struct rcu_random_state *rrsp)
 }
 
 static void
-rcu_stutter_wait(void)
+rcu_stutter_wait(char *title)
 {
-       while ((stutter_pause_test || !rcutorture_runnable) && !fullstop) {
+       while (stutter_pause_test || !rcutorture_runnable) {
                if (rcutorture_runnable)
                        schedule_timeout_interruptible(1);
                else
                        schedule_timeout_interruptible(round_jiffies_relative(HZ));
+               rcutorture_shutdown_absorb(title);
        }
 }
 
@@ -287,7 +306,7 @@ rcu_torture_cb(struct rcu_head *p)
        int i;
        struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu);
 
-       if (fullstop) {
+       if (fullstop != FULLSTOP_DONTSTOP) {
                /* Test is ending, just drop callbacks on the floor. */
                /* The next initialization will pick up the pieces. */
                return;
@@ -619,10 +638,11 @@ rcu_torture_writer(void *arg)
                }
                rcu_torture_current_version++;
                oldbatch = cur_ops->completed();
-               rcu_stutter_wait();
-       } while (!kthread_should_stop() && !fullstop);
+               rcu_stutter_wait("rcu_torture_writer");
+       } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
        VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping");
-       while (!kthread_should_stop() && fullstop != FULLSTOP_SHUTDOWN)
+       rcutorture_shutdown_absorb("rcu_torture_writer");
+       while (!kthread_should_stop())
                schedule_timeout_uninterruptible(1);
        return 0;
 }
@@ -643,11 +663,12 @@ rcu_torture_fakewriter(void *arg)
                schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10);
                udelay(rcu_random(&rand) & 0x3ff);
                cur_ops->sync();
-               rcu_stutter_wait();
-       } while (!kthread_should_stop() && !fullstop);
+               rcu_stutter_wait("rcu_torture_fakewriter");
+       } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
 
        VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping");
-       while (!kthread_should_stop() && fullstop != FULLSTOP_SHUTDOWN)
+       rcutorture_shutdown_absorb("rcu_torture_fakewriter");
+       while (!kthread_should_stop())
                schedule_timeout_uninterruptible(1);
        return 0;
 }
@@ -752,12 +773,13 @@ rcu_torture_reader(void *arg)
                preempt_enable();
                cur_ops->readunlock(idx);
                schedule();
-               rcu_stutter_wait();
-       } while (!kthread_should_stop() && !fullstop);
+               rcu_stutter_wait("rcu_torture_reader");
+       } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
        VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping");
+       rcutorture_shutdown_absorb("rcu_torture_reader");
        if (irqreader && cur_ops->irqcapable)
                del_timer_sync(&t);
-       while (!kthread_should_stop() && fullstop != FULLSTOP_SHUTDOWN)
+       while (!kthread_should_stop())
                schedule_timeout_uninterruptible(1);
        return 0;
 }
@@ -854,7 +876,8 @@ rcu_torture_stats(void *arg)
        do {
                schedule_timeout_interruptible(stat_interval * HZ);
                rcu_torture_stats_print();
-       } while (!kthread_should_stop() && !fullstop);
+               rcutorture_shutdown_absorb("rcu_torture_stats");
+       } while (!kthread_should_stop());
        VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping");
        return 0;
 }
@@ -866,52 +889,49 @@ static int rcu_idle_cpu;  /* Force all torture tasks off this CPU */
  */
 static void rcu_torture_shuffle_tasks(void)
 {
-       cpumask_var_t tmp_mask;
+       cpumask_t tmp_mask;
        int i;
 
-       if (!alloc_cpumask_var(&tmp_mask, GFP_KERNEL))
-               BUG();
-
-       cpumask_setall(tmp_mask);
+       cpus_setall(tmp_mask);
        get_online_cpus();
 
        /* No point in shuffling if there is only one online CPU (ex: UP) */
-       if (num_online_cpus() == 1)
-               goto out;
+       if (num_online_cpus() == 1) {
+               put_online_cpus();
+               return;
+       }
 
        if (rcu_idle_cpu != -1)
-               cpumask_clear_cpu(rcu_idle_cpu, tmp_mask);
+               cpu_clear(rcu_idle_cpu, tmp_mask);
 
-       set_cpus_allowed_ptr(current, tmp_mask);
+       set_cpus_allowed_ptr(current, &tmp_mask);
 
        if (reader_tasks) {
                for (i = 0; i < nrealreaders; i++)
                        if (reader_tasks[i])
                                set_cpus_allowed_ptr(reader_tasks[i],
-                                                    tmp_mask);
+                                                    &tmp_mask);
        }
 
        if (fakewriter_tasks) {
                for (i = 0; i < nfakewriters; i++)
                        if (fakewriter_tasks[i])
                                set_cpus_allowed_ptr(fakewriter_tasks[i],
-                                                    tmp_mask);
+                                                    &tmp_mask);
        }
 
        if (writer_task)
-               set_cpus_allowed_ptr(writer_task, tmp_mask);
+               set_cpus_allowed_ptr(writer_task, &tmp_mask);
 
        if (stats_task)
-               set_cpus_allowed_ptr(stats_task, tmp_mask);
+               set_cpus_allowed_ptr(stats_task, &tmp_mask);
 
        if (rcu_idle_cpu == -1)
                rcu_idle_cpu = num_online_cpus() - 1;
        else
                rcu_idle_cpu--;
 
-out:
        put_online_cpus();
-       free_cpumask_var(tmp_mask);
 }
 
 /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
@@ -925,7 +945,8 @@ rcu_torture_shuffle(void *arg)
        do {
                schedule_timeout_interruptible(shuffle_interval * HZ);
                rcu_torture_shuffle_tasks();
-       } while (!kthread_should_stop() && !fullstop);
+               rcutorture_shutdown_absorb("rcu_torture_shuffle");
+       } while (!kthread_should_stop());
        VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping");
        return 0;
 }
@@ -940,10 +961,11 @@ rcu_torture_stutter(void *arg)
        do {
                schedule_timeout_interruptible(stutter * HZ);
                stutter_pause_test = 1;
-               if (!kthread_should_stop() && !fullstop)
+               if (!kthread_should_stop())
                        schedule_timeout_interruptible(stutter * HZ);
                stutter_pause_test = 0;
-       } while (!kthread_should_stop() && !fullstop);
+               rcutorture_shutdown_absorb("rcu_torture_stutter");
+       } while (!kthread_should_stop());
        VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping");
        return 0;
 }
@@ -970,15 +992,16 @@ rcu_torture_cleanup(void)
        int i;
 
        mutex_lock(&fullstop_mutex);
-       if (!fullstop) {
-               /* If being signaled, let it happen, then exit. */
+       if (fullstop == FULLSTOP_SHUTDOWN) {
+               printk(KERN_WARNING /* but going down anyway, so... */
+                      "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
                mutex_unlock(&fullstop_mutex);
-               schedule_timeout_interruptible(10 * HZ);
+               schedule_timeout_uninterruptible(10);
                if (cur_ops->cb_barrier != NULL)
                        cur_ops->cb_barrier();
                return;
        }
-       fullstop = FULLSTOP_CLEANUP;
+       fullstop = FULLSTOP_RMMOD;
        mutex_unlock(&fullstop_mutex);
        unregister_reboot_notifier(&rcutorture_nb);
        if (stutter_task) {
@@ -1078,7 +1101,7 @@ rcu_torture_init(void)
        else
                nrealreaders = 2 * num_online_cpus();
        rcu_torture_print_module_parms("Start of test");
-       fullstop = 0;
+       fullstop = FULLSTOP_DONTSTOP;
 
        /* Set up the freelist. */
 

diff --git a/kernel/up.c b/kernel/up.c
new file mode 100644 (file)
index 0000000..c04b9dc
--- /dev/null
+++ b/kernel/up.c
@@ -0,0 +1,20 @@
+/*
+ * Uniprocessor-only support functions.  The counterpart to kernel/smp.c
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+
+int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
+                               int wait)
+{
+       WARN_ON(cpu != 0);
+
+       local_irq_disable();
+       (func)(info);
+       local_irq_enable();
+
+       return 0;
+}
+EXPORT_SYMBOL(smp_call_function_single);