diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cred.c | 2 | ||||
| -rw-r--r-- | kernel/events/core.c | 8 | ||||
| -rw-r--r-- | kernel/fork.c | 42 | ||||
| -rw-r--r-- | kernel/jump_label.c | 18 | ||||
| -rw-r--r-- | kernel/pm_qos_params.c | 70 | ||||
| -rw-r--r-- | kernel/power/hibernate.c | 220 | ||||
| -rw-r--r-- | kernel/rcutree.c | 208 | ||||
| -rw-r--r-- | kernel/rcutree.h | 30 | ||||
| -rw-r--r-- | kernel/rcutree_plugin.h | 33 | ||||
| -rw-r--r-- | kernel/rcutree_trace.c | 12 | ||||
| -rw-r--r-- | kernel/time/clockevents.c | 5 | ||||
| -rw-r--r-- | kernel/timer.c | 15 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 31 | ||||
| -rw-r--r-- | kernel/trace/ring_buffer.c | 10 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 15 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 7 | ||||
| -rw-r--r-- | kernel/trace/trace_output.c | 27 | ||||
| -rw-r--r-- | kernel/watchdog.c | 9 |
18 files changed, 426 insertions, 336 deletions
diff --git a/kernel/cred.c b/kernel/cred.c index e12c8af793f8..174fa84eca30 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -1,4 +1,4 @@ -/* Task credentials management - see Documentation/credentials.txt +/* Task credentials management - see Documentation/security/credentials.txt * * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) diff --git a/kernel/events/core.c b/kernel/events/core.c index c09767f7db3e..d863b3c057bb 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5028,6 +5028,14 @@ static int __perf_event_overflow(struct perf_event *event, int nmi, else perf_event_output(event, nmi, data, regs); + if (event->fasync && event->pending_kill) { + if (nmi) { + event->pending_wakeup = 1; + irq_work_queue(&event->pending); + } else + perf_event_wakeup(event); + } + return ret; } diff --git a/kernel/fork.c b/kernel/fork.c index ca406d916713..0276c30401a0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -484,20 +484,6 @@ static void mm_init_aio(struct mm_struct *mm) #endif } -int mm_init_cpumask(struct mm_struct *mm, struct mm_struct *oldmm) -{ -#ifdef CONFIG_CPUMASK_OFFSTACK - if (!alloc_cpumask_var(&mm->cpu_vm_mask_var, GFP_KERNEL)) - return -ENOMEM; - - if (oldmm) - cpumask_copy(mm_cpumask(mm), mm_cpumask(oldmm)); - else - memset(mm_cpumask(mm), 0, cpumask_size()); -#endif - return 0; -} - static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p) { atomic_set(&mm->mm_users, 1); @@ -538,17 +524,8 @@ struct mm_struct * mm_alloc(void) return NULL; memset(mm, 0, sizeof(*mm)); - mm = mm_init(mm, current); - if (!mm) - return NULL; - - if (mm_init_cpumask(mm, NULL)) { - mm_free_pgd(mm); - free_mm(mm); - return NULL; - } - - return mm; + mm_init_cpumask(mm); + return mm_init(mm, current); } /* @@ -559,7 +536,6 @@ struct mm_struct * mm_alloc(void) void __mmdrop(struct mm_struct *mm) { BUG_ON(mm == &init_mm); - free_cpumask_var(mm->cpu_vm_mask_var); mm_free_pgd(mm); destroy_context(mm); mmu_notifier_mm_destroy(mm); @@ -753,6 +729,7 @@ struct mm_struct *dup_mm(struct task_struct *tsk) goto fail_nomem; memcpy(mm, oldmm, sizeof(*mm)); + mm_init_cpumask(mm); /* Initializing for Swap token stuff */ mm->token_priority = 0; @@ -765,9 +742,6 @@ struct mm_struct *dup_mm(struct task_struct *tsk) if (!mm_init(mm, tsk)) goto fail_nomem; - if (mm_init_cpumask(mm, oldmm)) - goto fail_nocpumask; - if (init_new_context(tsk, mm)) goto fail_nocontext; @@ -794,9 +768,6 @@ fail_nomem: return NULL; fail_nocontext: - free_cpumask_var(mm->cpu_vm_mask_var); - -fail_nocpumask: /* * If init_new_context() failed, we cannot use mmput() to free the mm * because it calls destroy_context() @@ -1591,6 +1562,13 @@ void __init proc_caches_init(void) fs_cachep = kmem_cache_create("fs_cache", sizeof(struct fs_struct), 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK, NULL); + /* + * FIXME! The "sizeof(struct mm_struct)" currently includes the + * whole struct cpumask for the OFFSTACK case. We could change + * this to *only* allocate as much of it as required by the + * maximum number of CPU's we can ever have. The cpumask_allocation + * is at the end of the structure, exactly for that reason. + */ mm_cachep = kmem_cache_create("mm_struct", sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK, NULL); diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 74d1c099fbd1..fa27e750dbc0 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -105,9 +105,12 @@ static int __jump_label_text_reserved(struct jump_entry *iter_start, } static void __jump_label_update(struct jump_label_key *key, - struct jump_entry *entry, int enable) + struct jump_entry *entry, + struct jump_entry *stop, int enable) { - for (; entry->key == (jump_label_t)(unsigned long)key; entry++) { + for (; (entry < stop) && + (entry->key == (jump_label_t)(unsigned long)key); + entry++) { /* * entry->code set to 0 invalidates module init text sections * kernel_text_address() verifies we are not in core kernel @@ -181,7 +184,11 @@ static void __jump_label_mod_update(struct jump_label_key *key, int enable) struct jump_label_mod *mod = key->next; while (mod) { - __jump_label_update(key, mod->entries, enable); + struct module *m = mod->mod; + + __jump_label_update(key, mod->entries, + m->jump_entries + m->num_jump_entries, + enable); mod = mod->next; } } @@ -245,7 +252,8 @@ static int jump_label_add_module(struct module *mod) key->next = jlm; if (jump_label_enabled(key)) - __jump_label_update(key, iter, JUMP_LABEL_ENABLE); + __jump_label_update(key, iter, iter_stop, + JUMP_LABEL_ENABLE); } return 0; @@ -371,7 +379,7 @@ static void jump_label_update(struct jump_label_key *key, int enable) /* if there are no users, entry can be NULL */ if (entry) - __jump_label_update(key, entry, enable); + __jump_label_update(key, entry, __stop___jump_table, enable); #ifdef CONFIG_MODULES __jump_label_mod_update(key, enable); diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c index beb184689af9..6824ca7d4d0c 100644 --- a/kernel/pm_qos_params.c +++ b/kernel/pm_qos_params.c @@ -40,6 +40,7 @@ #include <linux/string.h> #include <linux/platform_device.h> #include <linux/init.h> +#include <linux/kernel.h> #include <linux/uaccess.h> @@ -53,11 +54,17 @@ enum pm_qos_type { PM_QOS_MIN /* return the smallest value */ }; +/* + * Note: The lockless read path depends on the CPU accessing + * target_value atomically. Atomic access is only guaranteed on all CPU + * types linux supports for 32 bit quantites + */ struct pm_qos_object { struct plist_head requests; struct blocking_notifier_head *notifiers; struct miscdevice pm_qos_power_miscdev; char *name; + s32 target_value; /* Do not change to 64 bit */ s32 default_value; enum pm_qos_type type; }; @@ -70,7 +77,8 @@ static struct pm_qos_object cpu_dma_pm_qos = { .requests = PLIST_HEAD_INIT(cpu_dma_pm_qos.requests, pm_qos_lock), .notifiers = &cpu_dma_lat_notifier, .name = "cpu_dma_latency", - .default_value = 2000 * USEC_PER_SEC, + .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, + .default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, .type = PM_QOS_MIN, }; @@ -79,7 +87,8 @@ static struct pm_qos_object network_lat_pm_qos = { .requests = PLIST_HEAD_INIT(network_lat_pm_qos.requests, pm_qos_lock), .notifiers = &network_lat_notifier, .name = "network_latency", - .default_value = 2000 * USEC_PER_SEC, + .target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, + .default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, .type = PM_QOS_MIN }; @@ -89,7 +98,8 @@ static struct pm_qos_object network_throughput_pm_qos = { .requests = PLIST_HEAD_INIT(network_throughput_pm_qos.requests, pm_qos_lock), .notifiers = &network_throughput_notifier, .name = "network_throughput", - .default_value = 0, + .target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, + .default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, .type = PM_QOS_MAX, }; @@ -135,6 +145,16 @@ static inline int pm_qos_get_value(struct pm_qos_object *o) } } +static inline s32 pm_qos_read_value(struct pm_qos_object *o) +{ + return o->target_value; +} + +static inline void pm_qos_set_value(struct pm_qos_object *o, s32 value) +{ + o->target_value = value; +} + static void update_target(struct pm_qos_object *o, struct plist_node *node, int del, int value) { @@ -159,6 +179,7 @@ static void update_target(struct pm_qos_object *o, struct plist_node *node, plist_add(node, &o->requests); } curr_value = pm_qos_get_value(o); + pm_qos_set_value(o, curr_value); spin_unlock_irqrestore(&pm_qos_lock, flags); if (prev_value != curr_value) @@ -193,18 +214,11 @@ static int find_pm_qos_object_by_minor(int minor) * pm_qos_request - returns current system wide qos expectation * @pm_qos_class: identification of which qos value is requested * - * This function returns the current target value in an atomic manner. + * This function returns the current target value. */ int pm_qos_request(int pm_qos_class) { - unsigned long flags; - int value; - - spin_lock_irqsave(&pm_qos_lock, flags); - value = pm_qos_get_value(pm_qos_array[pm_qos_class]); - spin_unlock_irqrestore(&pm_qos_lock, flags); - - return value; + return pm_qos_read_value(pm_qos_array[pm_qos_class]); } EXPORT_SYMBOL_GPL(pm_qos_request); @@ -404,24 +418,36 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, size_t count, loff_t *f_pos) { s32 value; - int x; - char ascii_value[11]; struct pm_qos_request_list *pm_qos_req; if (count == sizeof(s32)) { if (copy_from_user(&value, buf, sizeof(s32))) return -EFAULT; - } else if (count == 11) { /* len('0x12345678/0') */ - if (copy_from_user(ascii_value, buf, 11)) + } else if (count <= 11) { /* ASCII perhaps? */ + char ascii_value[11]; + unsigned long int ulval; + int ret; + + if (copy_from_user(ascii_value, buf, count)) return -EFAULT; - if (strlen(ascii_value) != 10) - return -EINVAL; - x = sscanf(ascii_value, "%x", &value); - if (x != 1) + + if (count > 10) { + if (ascii_value[10] == '\n') + ascii_value[10] = '\0'; + else + return -EINVAL; + } else { + ascii_value[count] = '\0'; + } + ret = strict_strtoul(ascii_value, 16, &ulval); + if (ret) { + pr_debug("%s, 0x%lx, 0x%x\n", ascii_value, ulval, ret); return -EINVAL; - pr_debug("%s, %d, 0x%x\n", ascii_value, x, value); - } else + } + value = (s32)lower_32_bits(ulval); + } else { return -EINVAL; + } pm_qos_req = filp->private_data; pm_qos_update_request(pm_qos_req, value); diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index f9bec56d8825..8f7b1db1ece1 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -25,7 +25,6 @@ #include <linux/gfp.h> #include <linux/syscore_ops.h> #include <scsi/scsi_scan.h> -#include <asm/suspend.h> #include "power.h" @@ -55,10 +54,9 @@ static int hibernation_mode = HIBERNATION_SHUTDOWN; static const struct platform_hibernation_ops *hibernation_ops; /** - * hibernation_set_ops - set the global hibernate operations - * @ops: the hibernation operations to use in subsequent hibernation transitions + * hibernation_set_ops - Set the global hibernate operations. + * @ops: Hibernation operations to use in subsequent hibernation transitions. */ - void hibernation_set_ops(const struct platform_hibernation_ops *ops) { if (ops && !(ops->begin && ops->end && ops->pre_snapshot @@ -115,10 +113,9 @@ static int hibernation_test(int level) { return 0; } #endif /* !CONFIG_PM_DEBUG */ /** - * platform_begin - tell the platform driver that we're starting - * hibernation + * platform_begin - Call platform to start hibernation. + * @platform_mode: Whether or not to use the platform driver. */ - static int platform_begin(int platform_mode) { return (platform_mode && hibernation_ops) ? @@ -126,10 +123,9 @@ static int platform_begin(int platform_mode) } /** - * platform_end - tell the platform driver that we've entered the - * working state + * platform_end - Call platform to finish transition to the working state. + * @platform_mode: Whether or not to use the platform driver. */ - static void platform_end(int platform_mode) { if (platform_mode && hibernation_ops) @@ -137,8 +133,11 @@ static void platform_end(int platform_mode) } /** - * platform_pre_snapshot - prepare the machine for hibernation using the - * platform driver if so configured and return an error code if it fails + * platform_pre_snapshot - Call platform to prepare the machine for hibernation. + * @platform_mode: Whether or not to use the platform driver. + * + * Use the platform driver to prepare the system for creating a hibernate image, + * if so configured, and return an error code if that fails. */ static int platform_pre_snapshot(int platform_mode) @@ -148,10 +147,14 @@ static int platform_pre_snapshot(int platform_mode) } /** - * platform_leave - prepare the machine for switching to the normal mode - * of operation using the platform driver (called with interrupts disabled) + * platform_leave - Call platform to prepare a transition to the working state. + * @platform_mode: Whether or not to use the platform driver. + * + * Use the platform driver prepare to prepare the machine for switching to the + * normal mode of operation. + * + * This routine is called on one CPU with interrupts disabled. */ - static void platform_leave(int platform_mode) { if (platform_mode && hibernation_ops) @@ -159,10 +162,14 @@ static void platform_leave(int platform_mode) } /** - * platform_finish - switch the machine to the normal mode of operation - * using the platform driver (must be called after platform_prepare()) + * platform_finish - Call platform to switch the system to the working state. + * @platform_mode: Whether or not to use the platform driver. + * + * Use the platform driver to switch the machine to the normal mode of + * operation. + * + * This routine must be called after platform_prepare(). */ - static void platform_finish(int platform_mode) { if (platform_mode && hibernation_ops) @@ -170,11 +177,15 @@ static void platform_finish(int platform_mode) } /** - * platform_pre_restore - prepare the platform for the restoration from a - * hibernation image. If the restore fails after this function has been - * called, platform_restore_cleanup() must be called. + * platform_pre_restore - Prepare for hibernate image restoration. + * @platform_mode: Whether or not to use the platform driver. + * + * Use the platform driver to prepare the system for resume from a hibernation + * image. + * + * If the restore fails after this function has been called, + * platform_restore_cleanup() must be called. */ - static int platform_pre_restore(int platform_mode) { return (platform_mode && hibernation_ops) ? @@ -182,12 +193,16 @@ static int platform_pre_restore(int platform_mode) } /** - * platform_restore_cleanup - switch the platform to the normal mode of - * operation after a failing restore. If platform_pre_restore() has been - * called before the failing restore, this function must be called too, - * regardless of the result of platform_pre_restore(). + * platform_restore_cleanup - Switch to the working state after failing restore. + * @platform_mode: Whether or not to use the platform driver. + * + * Use the platform driver to switch the system to the normal mode of operation + * after a failing restore. + * + * If platform_pre_restore() has been called before the failing restore, this + * function must be called too, regardless of the result of + * platform_pre_restore(). */ - static void platform_restore_cleanup(int platform_mode) { if (platform_mode && hibernation_ops) @@ -195,10 +210,9 @@ static void platform_restore_cleanup(int platform_mode) } /** - * platform_recover - recover the platform from a failure to suspend - * devices. + * platform_recover - Recover from a failure to suspend devices. + * @platform_mode: Whether or not to use the platform driver. */ - static void platform_recover(int platform_mode) { if (platform_mode && hibernation_ops && hibernation_ops->recover) @@ -206,13 +220,12 @@ static void platform_recover(int platform_mode) } /** - * swsusp_show_speed - print the time elapsed between two events. - * @start: Starting event. - * @stop: Final event. - * @nr_pages - number of pages processed between @start and @stop - * @msg - introductory message to print + * swsusp_show_speed - Print time elapsed between two events during hibernation. + * @start: Starting event. + * @stop: Final event. + * @nr_pages: Number of memory pages processed between @start and @stop. + * @msg: Additional diagnostic message to print. */ - void swsusp_show_speed(struct timeval *start, struct timeval *stop, unsigned nr_pages, char *msg) { @@ -235,25 +248,18 @@ void swsusp_show_speed(struct timeval *start, struct timeval *stop, } /** - * create_image - freeze devices that need to be frozen with interrupts - * off, create the hibernation image and thaw those devices. Control - * reappears in this routine after a restore. + * create_image - Create a hibernation image. + * @platform_mode: Whether or not to use the platform driver. + * + * Execute device drivers' .freeze_noirq() callbacks, create a hibernation image + * and execute the drivers' .thaw_noirq() callbacks. + * + * Control reappears in this routine after the subsequent restore. */ - static int create_image(int platform_mode) { int error; - error = arch_prepare_suspend(); - if (error) - return error; - - /* At this point, dpm_suspend_start() has been called, but *not* - * dpm_suspend_noirq(). We *must* call dpm_suspend_noirq() now. - * Otherwise, drivers for some devices (e.g. interrupt controllers) - * become desynchronized with the actual state of the hardware - * at resume time, and evil weirdness ensues. - */ error = dpm_suspend_noirq(PMSG_FREEZE); if (error) { printk(KERN_ERR "PM: Some devices failed to power down, " @@ -297,9 +303,6 @@ static int create_image(int platform_mode) Power_up: syscore_resume(); - /* NOTE: dpm_resume_noirq() is just a resume() for devices - * that suspended with irqs off ... no overall powerup. - */ Enable_irqs: local_irq_enable(); @@ -317,14 +320,11 @@ static int create_image(int platform_mode) } /** - * hibernation_snapshot - quiesce devices and create the hibernation - * snapshot image. - * @platform_mode - if set, use the platform driver, if available, to - * prepare the platform firmware for the power transition. + * hibernation_snapshot - Quiesce devices and create a hibernation image. + * @platform_mode: If set, use platform driver to prepare for the transition. * - * Must be called with pm_mutex held + * This routine must be called with pm_mutex held. */ - int hibernation_snapshot(int platform_mode) { pm_message_t msg = PMSG_RECOVER; @@ -384,13 +384,14 @@ int hibernation_snapshot(int platform_mode) } /** - * resume_target_kernel - prepare devices that need to be suspended with - * interrupts off, restore the contents of highmem that have not been - * restored yet from the image and run the low level code that will restore - * the remaining contents of memory and switch to the just restored target - * kernel. + * resume_target_kernel - Restore system state from a hibernation image. + * @platform_mode: Whether or not to use the platform driver. + * + * Execute device drivers' .freeze_noirq() callbacks, restore the contents of + * highmem that have not been restored yet from the image and run the low-level + * code that will restore the remaining contents of memory and switch to the + * just restored target kernel. */ - static int resume_target_kernel(bool platform_mode) { int error; @@ -416,24 +417,26 @@ static int resume_target_kernel(bool platform_mode) if (error) goto Enable_irqs; - /* We'll ignore saved state, but this gets preempt count (etc) right */ save_processor_state(); error = restore_highmem(); if (!error) { error = swsusp_arch_resume(); /* * The code below is only ever reached in case of a failure. - * Otherwise execution continues at place where - * swsusp_arch_suspend() was called + * Otherwise, execution continues at the place where + * swsusp_arch_suspend() was called. */ BUG_ON(!error); - /* This call to restore_highmem() undos the previous one */ + /* + * This call to restore_highmem() reverts the changes made by + * the previous one. + */ restore_highmem(); } /* * The only reason why swsusp_arch_resume() can fail is memory being * very tight, so we have to free it as soon as we can to avoid - * subsequent failures + * subsequent failures. */ swsusp_free(); restore_processor_state(); @@ -456,14 +459,12 @@ static int resume_target_kernel(bool platform_mode) } /** - * hibernation_restore - quiesce devices and restore the hibernation - * snapshot image. If successful, control returns in hibernation_snaphot() - * @platform_mode - if set, use the platform driver, if available, to - * prepare the platform firmware for the transition. + * hibernation_restore - Quiesce devices and restore from a hibernation image. + * @platform_mode: If set, use platform driver to prepare for the transition. * - * Must be called with pm_mutex held + * This routine must be called with pm_mutex held. If it is successful, control + * reappears in the restored target kernel in hibernation_snaphot(). */ - int hibernation_restore(int platform_mode) { int error; @@ -483,10 +484,8 @@ int hibernation_restore(int platform_mode) } /** - * hibernation_platform_enter - enter the hibernation state using the - * platform driver (if available) + * hibernation_platform_enter - Power off the system using the platform driver. */ - int hibernation_platform_enter(void) { int error; @@ -557,12 +556,12 @@ int hibernation_platform_enter(void) } /** - * power_down - Shut the machine down for hibernation. + * power_down - Shut the machine down for hibernation. * - * Use the platform driver, if configured so; otherwise try - * to power off or reboot. + * Use the platform driver, if configured, to put the system into the sleep + * state corresponding to hibernation, or try to power it off or reboot, + * depending on the value of hibernation_mode. */ - static void power_down(void) { switch (hibernation_mode) { @@ -599,9 +598,8 @@ static int prepare_processes(void) } /** - * hibernate - The granpappy of the built-in hibernation management + * hibernate - Carry out system hibernation, including saving the image. */ - int hibernate(void) { int error; @@ -679,17 +677,20 @@ int hibernate(void) /** - * software_resume - Resume from a saved image. + * software_resume - Resume from a saved hibernation image. * - * Called as a late_initcall (so all devices are discovered and - * initialized), we call swsusp to see if we have a saved image or not. - * If so, we quiesce devices, the restore the saved image. We will - * return above (in hibernate() ) if everything goes well. - * Otherwise, we fail gracefully and return to the normally - * scheduled program. + * This routine is called as a late initcall, when all devices have been + * discovered and initialized already. * + * The image reading code is called to see if there is a hibernation image + * available for reading. If that is the case, devices are quiesced and the + * contents of memory is restored from the saved image. + * + * If this is successful, control reappears in the restored target kernel in + * hibernation_snaphot() which returns to hibernate(). Otherwise, the routine + * attempts to recover gracefully and make the kernel return to the normal mode + * of operation. */ - static int software_resume(void) { int error; @@ -819,21 +820,17 @@ static const char * const hibernation_modes[] = { [HIBERNATION_TESTPROC] = "testproc", }; -/** - * disk - Control hibernation mode - * - * Suspend-to-disk can be handled in several ways. We have a few options - * for putting the system to sleep - using the platform driver (e.g. ACPI - * or other hibernation_ops), powering off the system or rebooting the - * system (for testing) as well as the two test modes. +/* + * /sys/power/disk - Control hibernation mode. * - * The system can support 'platform', and that is known a priori (and - * encoded by the presence of hibernation_ops). However, the user may - * choose 'shutdown' or 'reboot' as alternatives, as well as one fo the - * test modes, 'test' or 'testproc'. + * Hibernation can be handled in several ways. There are a few different ways + * to put the system into the sleep state: using the platform driver (e.g. ACPI + * or other hibernation_ops), powering it off or rebooting it (for testing + * mostly), or using one of the two available test modes. * - * show() will display what the mode is currently set to. - * store() will accept one of + * The sysfs file /sys/power/disk provides an interface for selecting the + * hibernation mode to use. Reading from this file causes the available modes + * to be printed. There are 5 modes that can be supported: * * 'platform' * 'shutdown' @@ -841,8 +838,14 @@ static const char * const hibernation_modes[] = { * 'test' * 'testproc' * - * It will only change to 'platform' if the system - * supports it (as determined by having hibernation_ops). + * If a platform hibernation driver is in use, 'platform' will be supported + * and will be used by default. Otherwise, 'shutdown' will be used by default. + * The selected option (i.e. the one corresponding to the current value of + * hibernation_mode) is enclosed by a square bracket. + * + * To select a given hibernation mode it is necessary to write the mode's + * string representation (as returned by reading from /sys/power/disk) back + * into /sys/power/disk. */ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, @@ -875,7 +878,6 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, return buf-start; } - static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t n) { diff --git a/kernel/rcutree.c b/kernel/rcutree.c index f07d2f03181a..89419ff92e99 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -36,7 +36,7 @@ #include <linux/interrupt.h> #include <linux/sched.h> #include <linux/nmi.h> -#include <asm/atomic.h> +#include <linux/atomic.h> #include <linux/bitops.h> #include <linux/module.h> #include <linux/completion.h> @@ -95,7 +95,6 @@ static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task); DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status); DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu); DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); -static DEFINE_PER_CPU(wait_queue_head_t, rcu_cpu_wq); DEFINE_PER_CPU(char, rcu_cpu_has_work); static char rcu_kthreads_spawnable; @@ -163,7 +162,7 @@ EXPORT_SYMBOL_GPL(rcu_note_context_switch); #ifdef CONFIG_NO_HZ DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { .dynticks_nesting = 1, - .dynticks = 1, + .dynticks = ATOMIC_INIT(1), }; #endif /* #ifdef CONFIG_NO_HZ */ @@ -322,13 +321,25 @@ void rcu_enter_nohz(void) unsigned long flags; struct rcu_dynticks *rdtp; - smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */ local_irq_save(flags); rdtp = &__get_cpu_var(rcu_dynticks); - rdtp->dynticks++; - rdtp->dynticks_nesting--; - WARN_ON_ONCE(rdtp->dynticks & 0x1); + if (--rdtp->dynticks_nesting) { + local_irq_restore(flags); + return; + } + /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */ + smp_mb__before_atomic_inc(); /* See above. */ + atomic_inc(&rdtp->dynticks); + smp_mb__after_atomic_inc(); /* Force ordering with next sojourn. */ + WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1); local_irq_restore(flags); + + /* If the interrupt queued a callback, get out of dyntick mode. */ + if (in_irq() && + (__get_cpu_var(rcu_sched_data).nxtlist || + __get_cpu_var(rcu_bh_data).nxtlist || + rcu_preempt_needs_cpu(smp_processor_id()))) + set_need_resched(); } /* @@ -344,11 +355,16 @@ void rcu_exit_nohz(void) local_irq_save(flags); rdtp = &__get_cpu_var(rcu_dynticks); - rdtp->dynticks++; - rdtp->dynticks_nesting++; - WARN_ON_ONCE(!(rdtp->dynticks & 0x1)); + if (rdtp->dynticks_nesting++) { + local_irq_restore(flags); + return; + } + smp_mb__before_atomic_inc(); /* Force ordering w/previous sojourn. */ + atomic_inc(&rdtp->dynticks); + /* CPUs seeing atomic_inc() must see later RCU read-side crit sects */ + smp_mb__after_atomic_inc(); /* See above. */ + WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1)); local_irq_restore(flags); - smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */ } /** @@ -362,11 +378,15 @@ void rcu_nmi_enter(void) { struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks); - if (rdtp->dynticks & 0x1) + if (rdtp->dynticks_nmi_nesting == 0 && + (atomic_read(&rdtp->dynticks) & 0x1)) return; - rdtp->dynticks_nmi++; - WARN_ON_ONCE(!(rdtp->dynticks_nmi & 0x1)); - smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */ + rdtp->dynticks_nmi_nesting++; + smp_mb__before_atomic_inc(); /* Force delay from prior write. */ + atomic_inc(&rdtp->dynticks); + /* CPUs seeing atomic_inc() must see later RCU read-side crit sects */ + smp_mb__after_atomic_inc(); /* See above. */ + WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1)); } /** @@ -380,11 +400,14 @@ void rcu_nmi_exit(void) { struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks); - if (rdtp->dynticks & 0x1) + if (rdtp->dynticks_nmi_nesting == 0 || + --rdtp->dynticks_nmi_nesting != 0) return; - smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */ - rdtp->dynticks_nmi++; - WARN_ON_ONCE(rdtp->dynticks_nmi & 0x1); + /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */ + smp_mb__before_atomic_inc(); /* See above. */ + atomic_inc(&rdtp->dynticks); + smp_mb__after_atomic_inc(); /* Force delay to next write. */ + WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1); } /** @@ -395,13 +418,7 @@ void rcu_nmi_exit(void) */ void rcu_irq_enter(void) { - struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks); - - if (rdtp->dynticks_nesting++) - return; - rdtp->dynticks++; - WARN_ON_ONCE(!(rdtp->dynticks & 0x1)); - smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */ + rcu_exit_nohz(); } /** @@ -413,18 +430,7 @@ void rcu_irq_enter(void) */ void rcu_irq_exit(void) { - struct rcu_dynticks *rdtp = &__get_cpu_var(rcu_dynticks); - - if (--rdtp->dynticks_nesting) - return; - smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */ - rdtp->dynticks++; - WARN_ON_ONCE(rdtp->dynticks & 0x1); - - /* If the interrupt queued a callback, get out of dyntick mode. */ - if (__this_cpu_read(rcu_sched_data.nxtlist) || - __this_cpu_read(rcu_bh_data.nxtlist)) - set_need_resched(); + rcu_enter_nohz(); } #ifdef CONFIG_SMP @@ -436,19 +442,8 @@ void rcu_irq_exit(void) */ static int dyntick_save_progress_counter(struct rcu_data *rdp) { - int ret; - int snap; - int snap_nmi; - - snap = rdp->dynticks->dynticks; - snap_nmi = rdp->dynticks->dynticks_nmi; |