diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cpuset.c | 24 | ||||
| -rw-r--r-- | kernel/irq/handle.c | 1 | ||||
| -rw-r--r-- | kernel/power/main.c | 6 | ||||
| -rw-r--r-- | kernel/printk.c | 72 | ||||
| -rw-r--r-- | kernel/profile.c | 16 | ||||
| -rw-r--r-- | kernel/sched.c | 2 | ||||
| -rw-r--r-- | kernel/signal.c | 11 | ||||
| -rw-r--r-- | kernel/spinlock.c | 8 |
8 files changed, 84 insertions, 56 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 961d74044de..00e8f257551 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -166,9 +166,8 @@ static struct super_block *cpuset_sb = NULL; * The hooks from fork and exit, cpuset_fork() and cpuset_exit(), don't * (usually) grab cpuset_sem. These are the two most performance * critical pieces of code here. The exception occurs on exit(), - * if the last task using a cpuset exits, and the cpuset was marked - * notify_on_release. In that case, the cpuset_sem is taken, the - * path to the released cpuset calculated, and a usermode call made + * when a task in a notify_on_release cpuset exits. Then cpuset_sem + * is taken, and if the cpuset count is zero, a usermode call made * to /sbin/cpuset_release_agent with the name of the cpuset (path * relative to the root of cpuset file system) as the argument. * @@ -1404,6 +1403,18 @@ void cpuset_fork(struct task_struct *tsk) * * Description: Detach cpuset from @tsk and release it. * + * Note that cpusets marked notify_on_release force every task + * in them to take the global cpuset_sem semaphore when exiting. + * This could impact scaling on very large systems. Be reluctant + * to use notify_on_release cpusets where very high task exit + * scaling is required on large systems. + * + * Don't even think about derefencing 'cs' after the cpuset use + * count goes to zero, except inside a critical section guarded + * by the cpuset_sem semaphore. If you don't hold cpuset_sem, + * then a zero cpuset use count is a license to any other task to + * nuke the cpuset immediately. + * **/ void cpuset_exit(struct task_struct *tsk) @@ -1415,10 +1426,13 @@ void cpuset_exit(struct task_struct *tsk) tsk->cpuset = NULL; task_unlock(tsk); - if (atomic_dec_and_test(&cs->count)) { + if (notify_on_release(cs)) { down(&cpuset_sem); - check_for_release(cs); + if (atomic_dec_and_test(&cs->count)) + check_for_release(cs); up(&cpuset_sem); + } else { + atomic_dec(&cs->count); } } diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c index 2fb0e46e11f..06b5a632399 100644 --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -30,6 +30,7 @@ */ irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = { [0 ... NR_IRQS-1] = { + .status = IRQ_DISABLED, .handler = &no_irq_type, .lock = SPIN_LOCK_UNLOCKED } diff --git a/kernel/power/main.c b/kernel/power/main.c index 7960ddf04a5..4cdebc972ff 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -156,14 +156,14 @@ static int enter_state(suspend_state_t state) goto Unlock; } - pr_debug("PM: Preparing system for suspend\n"); + pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); if ((error = suspend_prepare(state))) goto Unlock; - pr_debug("PM: Entering state.\n"); + pr_debug("PM: Entering %s sleep\n", pm_states[state]); error = suspend_enter(state); - pr_debug("PM: Finishing up.\n"); + pr_debug("PM: Finishing wakeup.\n"); suspend_finish(state); Unlock: up(&pm_sem); diff --git a/kernel/printk.c b/kernel/printk.c index 290a07ce2c8..01b58d7d17f 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -160,42 +160,6 @@ static int __init console_setup(char *str) __setup("console=", console_setup); -/** - * add_preferred_console - add a device to the list of preferred consoles. - * - * The last preferred console added will be used for kernel messages - * and stdin/out/err for init. Normally this is used by console_setup - * above to handle user-supplied console arguments; however it can also - * be used by arch-specific code either to override the user or more - * commonly to provide a default console (ie from PROM variables) when - * the user has not supplied one. - */ -int __init add_preferred_console(char *name, int idx, char *options) -{ - struct console_cmdline *c; - int i; - - /* - * See if this tty is not yet registered, and - * if we have a slot free. - */ - for(i = 0; i < MAX_CMDLINECONSOLES && console_cmdline[i].name[0]; i++) - if (strcmp(console_cmdline[i].name, name) == 0 && - console_cmdline[i].index == idx) { - selected_console = i; - return 0; - } - if (i == MAX_CMDLINECONSOLES) - return -E2BIG; - selected_console = i; - c = &console_cmdline[i]; - memcpy(c->name, name, sizeof(c->name)); - c->name[sizeof(c->name) - 1] = 0; - c->options = options; - c->index = idx; - return 0; -} - static int __init log_buf_len_setup(char *str) { unsigned long size = memparse(str, &str); @@ -671,6 +635,42 @@ static void call_console_drivers(unsigned long start, unsigned long end) {} #endif /** + * add_preferred_console - add a device to the list of preferred consoles. + * + * The last preferred console added will be used for kernel messages + * and stdin/out/err for init. Normally this is used by console_setup + * above to handle user-supplied console arguments; however it can also + * be used by arch-specific code either to override the user or more + * commonly to provide a default console (ie from PROM variables) when + * the user has not supplied one. + */ +int __init add_preferred_console(char *name, int idx, char *options) +{ + struct console_cmdline *c; + int i; + + /* + * See if this tty is not yet registered, and + * if we have a slot free. + */ + for(i = 0; i < MAX_CMDLINECONSOLES && console_cmdline[i].name[0]; i++) + if (strcmp(console_cmdline[i].name, name) == 0 && + console_cmdline[i].index == idx) { + selected_console = i; + return 0; + } + if (i == MAX_CMDLINECONSOLES) + return -E2BIG; + selected_console = i; + c = &console_cmdline[i]; + memcpy(c->name, name, sizeof(c->name)); + c->name[sizeof(c->name) - 1] = 0; + c->options = options; + c->index = idx; + return 0; +} + +/** * acquire_console_sem - lock the console system for exclusive use. * * Acquires a semaphore which guarantees that the caller has diff --git a/kernel/profile.c b/kernel/profile.c index 0221a50ca86..ad8cbb75ffa 100644 --- a/kernel/profile.c +++ b/kernel/profile.c @@ -49,15 +49,19 @@ static DECLARE_MUTEX(profile_flip_mutex); static int __init profile_setup(char * str) { + static char __initdata schedstr[] = "schedule"; int par; - if (!strncmp(str, "schedule", 8)) { + if (!strncmp(str, schedstr, strlen(schedstr))) { prof_on = SCHED_PROFILING; - printk(KERN_INFO "kernel schedule profiling enabled\n"); - if (str[7] == ',') - str += 8; - } - if (get_option(&str,&par)) { + if (str[strlen(schedstr)] == ',') + str += strlen(schedstr) + 1; + if (get_option(&str, &par)) + prof_shift = par; + printk(KERN_INFO + "kernel schedule profiling enabled (shift: %ld)\n", + prof_shift); + } else if (get_option(&str, &par)) { prof_shift = par; prof_on = CPU_PROFILING; printk(KERN_INFO "kernel profiling enabled (shift: %ld)\n", diff --git a/kernel/sched.c b/kernel/sched.c index 0dc3158667a..66b2ed78482 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -4243,7 +4243,7 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *tsk) /* No more Mr. Nice Guy. */ if (dest_cpu == NR_CPUS) { - tsk->cpus_allowed = cpuset_cpus_allowed(tsk); + cpus_setall(tsk->cpus_allowed); dest_cpu = any_online_cpu(tsk->cpus_allowed); /* diff --git a/kernel/signal.c b/kernel/signal.c index 8f3debc77c5..b3c24c732c5 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -522,7 +522,16 @@ static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, { int sig = 0; - sig = next_signal(pending, mask); + /* SIGKILL must have priority, otherwise it is quite easy + * to create an unkillable process, sending sig < SIGKILL + * to self */ + if (unlikely(sigismember(&pending->signal, SIGKILL))) { + if (!sigismember(mask, SIGKILL)) + sig = SIGKILL; + } + + if (likely(!sig)) + sig = next_signal(pending, mask); if (sig) { if (current->notifier) { if (sigismember(current->notifier_mask, sig)) { diff --git a/kernel/spinlock.c b/kernel/spinlock.c index e15ed17863f..0c3f9d8bbe1 100644 --- a/kernel/spinlock.c +++ b/kernel/spinlock.c @@ -294,7 +294,7 @@ EXPORT_SYMBOL(_spin_unlock_irq); void __lockfunc _spin_unlock_bh(spinlock_t *lock) { _raw_spin_unlock(lock); - preempt_enable(); + preempt_enable_no_resched(); local_bh_enable(); } EXPORT_SYMBOL(_spin_unlock_bh); @@ -318,7 +318,7 @@ EXPORT_SYMBOL(_read_unlock_irq); void __lockfunc _read_unlock_bh(rwlock_t *lock) { _raw_read_unlock(lock); - preempt_enable(); + preempt_enable_no_resched(); local_bh_enable(); } EXPORT_SYMBOL(_read_unlock_bh); @@ -342,7 +342,7 @@ EXPORT_SYMBOL(_write_unlock_irq); void __lockfunc _write_unlock_bh(rwlock_t *lock) { _raw_write_unlock(lock); - preempt_enable(); + preempt_enable_no_resched(); local_bh_enable(); } EXPORT_SYMBOL(_write_unlock_bh); @@ -354,7 +354,7 @@ int __lockfunc _spin_trylock_bh(spinlock_t *lock) if (_raw_spin_trylock(lock)) return 1; - preempt_enable(); + preempt_enable_no_resched(); local_bh_enable(); return 0; } |