diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/audit.c | 2 | ||||
-rw-r--r-- | kernel/cpuset.c | 537 | ||||
-rw-r--r-- | kernel/exit.c | 4 | ||||
-rw-r--r-- | kernel/fork.c | 33 | ||||
-rw-r--r-- | kernel/irq/proc.c | 2 | ||||
-rw-r--r-- | kernel/module.c | 56 | ||||
-rw-r--r-- | kernel/pid.c | 22 | ||||
-rw-r--r-- | kernel/printk.c | 6 | ||||
-rw-r--r-- | kernel/ptrace.c | 77 | ||||
-rw-r--r-- | kernel/rcupdate.c | 19 | ||||
-rw-r--r-- | kernel/rcutorture.c | 99 | ||||
-rw-r--r-- | kernel/sched.c | 7 | ||||
-rw-r--r-- | kernel/signal.c | 137 | ||||
-rw-r--r-- | kernel/sys.c | 62 | ||||
-rw-r--r-- | kernel/sys_ni.c | 22 | ||||
-rw-r--r-- | kernel/sysctl.c | 22 | ||||
-rw-r--r-- | kernel/timer.c | 1 | ||||
-rw-r--r-- | kernel/workqueue.c | 40 |
18 files changed, 908 insertions, 240 deletions
diff --git a/kernel/audit.c b/kernel/audit.c index 32fa03ad198..d13ab7d2d89 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -267,7 +267,7 @@ static int audit_set_failure(int state, uid_t loginuid) return old; } -int kauditd_thread(void *dummy) +static int kauditd_thread(void *dummy) { struct sk_buff *skb; diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 7430640f981..eab64e23bca 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -39,6 +39,7 @@ #include <linux/namei.h> #include <linux/pagemap.h> #include <linux/proc_fs.h> +#include <linux/rcupdate.h> #include <linux/sched.h> #include <linux/seq_file.h> #include <linux/slab.h> @@ -54,7 +55,23 @@ #include <asm/atomic.h> #include <asm/semaphore.h> -#define CPUSET_SUPER_MAGIC 0x27e0eb +#define CPUSET_SUPER_MAGIC 0x27e0eb + +/* + * Tracks how many cpusets are currently defined in system. + * When there is only one cpuset (the root cpuset) we can + * short circuit some hooks. + */ +int number_of_cpusets __read_mostly; + +/* See "Frequency meter" comments, below. */ + +struct fmeter { + int cnt; /* unprocessed events count */ + int val; /* most recent output value */ + time_t time; /* clock (secs) when val computed */ + spinlock_t lock; /* guards read or write of above */ +}; struct cpuset { unsigned long flags; /* "unsigned long" so bitops work */ @@ -80,13 +97,16 @@ struct cpuset { * Copy of global cpuset_mems_generation as of the most * recent time this cpuset changed its mems_allowed. */ - int mems_generation; + int mems_generation; + + struct fmeter fmeter; /* memory_pressure filter */ }; /* bits in struct cpuset flags field */ typedef enum { CS_CPU_EXCLUSIVE, CS_MEM_EXCLUSIVE, + CS_MEMORY_MIGRATE, CS_REMOVED, CS_NOTIFY_ON_RELEASE } cpuset_flagbits_t; @@ -112,6 +132,11 @@ static inline int notify_on_release(const struct cpuset *cs) return !!test_bit(CS_NOTIFY_ON_RELEASE, &cs->flags); } +static inline int is_memory_migrate(const struct cpuset *cs) +{ + return !!test_bit(CS_MEMORY_MIGRATE, &cs->flags); +} + /* * Increment this atomic integer everytime any cpuset changes its * mems_allowed value. Users of cpusets can track this generation @@ -137,13 +162,10 @@ static struct cpuset top_cpuset = { .count = ATOMIC_INIT(0), .sibling = LIST_HEAD_INIT(top_cpuset.sibling), .children = LIST_HEAD_INIT(top_cpuset.children), - .parent = NULL, - .dentry = NULL, - .mems_generation = 0, }; static struct vfsmount *cpuset_mount; -static struct super_block *cpuset_sb = NULL; +static struct super_block *cpuset_sb; /* * We have two global cpuset semaphores below. They can nest. @@ -227,6 +249,11 @@ static struct super_block *cpuset_sb = NULL; * a tasks cpuset pointer we use task_lock(), which acts on a spinlock * (task->alloc_lock) already in the task_struct routinely used for * such matters. + * + * P.S. One more locking exception. RCU is used to guard the + * update of a tasks cpuset pointer by attach_task() and the + * access of task->cpuset->mems_generation via that pointer in + * the routine cpuset_update_task_memory_state(). */ static DECLARE_MUTEX(manage_sem); @@ -304,7 +331,7 @@ static void cpuset_d_remove_dir(struct dentry *dentry) spin_lock(&dcache_lock); node = dentry->d_subdirs.next; while (node != &dentry->d_subdirs) { - struct dentry *d = list_entry(node, struct dentry, d_child); + struct dentry *d = list_entry(node, struct dentry, d_u.d_child); list_del_init(node); if (d->d_inode) { d = dget_locked(d); @@ -316,7 +343,7 @@ static void cpuset_d_remove_dir(struct dentry *dentry) } node = dentry->d_subdirs.next; } - list_del_init(&dentry->d_child); + list_del_init(&dentry->d_u.d_child); spin_unlock(&dcache_lock); remove_dir(dentry); } @@ -570,20 +597,43 @@ static void guarantee_online_mems(const struct cpuset *cs, nodemask_t *pmask) BUG_ON(!nodes_intersects(*pmask, node_online_map)); } -/* - * Refresh current tasks mems_allowed and mems_generation from current - * tasks cpuset. +/** + * cpuset_update_task_memory_state - update task memory placement * - * Call without callback_sem or task_lock() held. May be called with - * or without manage_sem held. Will acquire task_lock() and might - * acquire callback_sem during call. + * If the current tasks cpusets mems_allowed changed behind our + * backs, update current->mems_allowed, mems_generation and task NUMA + * mempolicy to the new value. + * + * Task mempolicy is updated by rebinding it relative to the + * current->cpuset if a task has its memory placement changed. + * Do not call this routine if in_interrupt(). * - * The task_lock() is required to dereference current->cpuset safely. - * Without it, we could pick up the pointer value of current->cpuset - * in one instruction, and then attach_task could give us a different - * cpuset, and then the cpuset we had could be removed and freed, - * and then on our next instruction, we could dereference a no longer - * valid cpuset pointer to get its mems_generation field. + * Call without callback_sem or task_lock() held. May be called + * with or without manage_sem held. Doesn't need task_lock to guard + * against another task changing a non-NULL cpuset pointer to NULL, + * as that is only done by a task on itself, and if the current task + * is here, it is not simultaneously in the exit code NULL'ing its + * cpuset pointer. This routine also might acquire callback_sem and + * current->mm->mmap_sem during call. + * + * Reading current->cpuset->mems_generation doesn't need task_lock + * to guard the current->cpuset derefence, because it is guarded + * from concurrent freeing of current->cpuset by attach_task(), + * using RCU. + * + * The rcu_dereference() is technically probably not needed, + * as I don't actually mind if I see a new cpuset pointer but + * an old value of mems_generation. However this really only + * matters on alpha systems using cpusets heavily. If I dropped + * that rcu_dereference(), it would save them a memory barrier. + * For all other arch's, rcu_dereference is a no-op anyway, and for + * alpha systems not using cpusets, another planned optimization, + * avoiding the rcu critical section for tasks in the root cpuset + * which is statically allocated, so can't vanish, will make this + * irrelevant. Better to use RCU as intended, than to engage in + * some cute trick to save a memory barrier that is impossible to + * test, for alpha systems using cpusets heavily, which might not + * even exist. * * This routine is needed to update the per-task mems_allowed data, * within the tasks context, when it is trying to allocate memory @@ -591,27 +641,31 @@ static void guarantee_online_mems(const struct cpuset *cs, nodemask_t *pmask) * task has been modifying its cpuset. */ -static void refresh_mems(void) +void cpuset_update_task_memory_state() { int my_cpusets_mem_gen; + struct task_struct *tsk = current; + struct cpuset *cs; - task_lock(current); - my_cpusets_mem_gen = current->cpuset->mems_generation; - task_unlock(current); - - if (current->cpuset_mems_generation != my_cpusets_mem_gen) { - struct cpuset *cs; - nodemask_t oldmem = current->mems_allowed; + if (tsk->cpuset == &top_cpuset) { + /* Don't need rcu for top_cpuset. It's never freed. */ + my_cpusets_mem_gen = top_cpuset.mems_generation; + } else { + rcu_read_lock(); + cs = rcu_dereference(tsk->cpuset); + my_cpusets_mem_gen = cs->mems_generation; + rcu_read_unlock(); + } + if (my_cpusets_mem_gen != tsk->cpuset_mems_generation) { down(&callback_sem); - task_lock(current); - cs = current->cpuset; - guarantee_online_mems(cs, ¤t->mems_allowed); - current->cpuset_mems_generation = cs->mems_generation; - task_unlock(current); + task_lock(tsk); + cs = tsk->cpuset; /* Maybe changed when task not locked */ + guarantee_online_mems(cs, &tsk->mems_allowed); + tsk->cpuset_mems_generation = cs->mems_generation; + task_unlock(tsk); up(&callback_sem); - if (!nodes_equal(oldmem, current->mems_allowed)) - numa_policy_rebind(&oldmem, ¤t->mems_allowed); + mpol_rebind_task(tsk, &tsk->mems_allowed); } } @@ -766,36 +820,150 @@ static int update_cpumask(struct cpuset *cs, char *buf) } /* + * Handle user request to change the 'mems' memory placement + * of a cpuset. Needs to validate the request, update the + * cpusets mems_allowed and mems_generation, and for each + * task in the cpuset, rebind any vma mempolicies and if + * the cpuset is marked 'memory_migrate', migrate the tasks + * pages to the new memory. + * * Call with manage_sem held. May take callback_sem during call. + * Will take tasklist_lock, scan tasklist for tasks in cpuset cs, + * lock each such tasks mm->mmap_sem, scan its vma's and rebind + * their mempolicies to the cpusets new mems_allowed. */ static int update_nodemask(struct cpuset *cs, char *buf) { struct cpuset trialcs; + nodemask_t oldmem; + struct task_struct *g, *p; + struct mm_struct **mmarray; + int i, n, ntasks; + int migrate; + int fudge; int retval; trialcs = *cs; retval = nodelist_parse(buf, trialcs.mems_allowed); if (retval < 0) - return retval; + goto done; nodes_and(trialcs.mems_allowed, trialcs.mems_allowed, node_online_map); - if (nodes_empty(trialcs.mems_allowed)) - return -ENOSPC; + oldmem = cs->mems_allowed; + if (nodes_equal(oldmem, trialcs.mems_allowed)) { + retval = 0; /* Too easy - nothing to do */ + goto done; + } + if (nodes_empty(trialcs.mems_allowed)) { + retval = -ENOSPC; + goto done; + } retval = validate_change(cs, &trialcs); - if (retval == 0) { - down(&callback_sem); - cs->mems_allowed = trialcs.mems_allowed; - atomic_inc(&cpuset_mems_generation); - cs->mems_generation = atomic_read(&cpuset_mems_generation); - up(&callback_sem); + if (retval < 0) + goto done; + + down(&callback_sem); + cs->mems_allowed = trialcs.mems_allowed; + atomic_inc(&cpuset_mems_generation); + cs->mems_generation = atomic_read(&cpuset_mems_generation); + up(&callback_sem); + + set_cpuset_being_rebound(cs); /* causes mpol_copy() rebind */ + + fudge = 10; /* spare mmarray[] slots */ + fudge += cpus_weight(cs->cpus_allowed); /* imagine one fork-bomb/cpu */ + retval = -ENOMEM; + + /* + * Allocate mmarray[] to hold mm reference for each task + * in cpuset cs. Can't kmalloc GFP_KERNEL while holding + * tasklist_lock. We could use GFP_ATOMIC, but with a + * few more lines of code, we can retry until we get a big + * enough mmarray[] w/o using GFP_ATOMIC. + */ + while (1) { + ntasks = atomic_read(&cs->count); /* guess */ + ntasks += fudge; + mmarray = kmalloc(ntasks * sizeof(*mmarray), GFP_KERNEL); + if (!mmarray) + goto done; + write_lock_irq(&tasklist_lock); /* block fork */ + if (atomic_read(&cs->count) <= ntasks) + break; /* got enough */ + write_unlock_irq(&tasklist_lock); /* try again */ + kfree(mmarray); } + + n = 0; + + /* Load up mmarray[] with mm reference for each task in cpuset. */ + do_each_thread(g, p) { + struct mm_struct *mm; + + if (n >= ntasks) { + printk(KERN_WARNING + "Cpuset mempolicy rebind incomplete.\n"); + continue; + } + if (p->cpuset != cs) + continue; + mm = get_task_mm(p); + if (!mm) + continue; + mmarray[n++] = mm; + } while_each_thread(g, p); + write_unlock_irq(&tasklist_lock); + + /* + * Now that we've dropped the tasklist spinlock, we can + * rebind the vma mempolicies of each mm in mmarray[] to their + * new cpuset, and release that mm. The mpol_rebind_mm() + * call takes mmap_sem, which we couldn't take while holding + * tasklist_lock. Forks can happen again now - the mpol_copy() + * cpuset_being_rebound check will catch such forks, and rebind + * their vma mempolicies too. Because we still hold the global + * cpuset manage_sem, we know that no other rebind effort will + * be contending for the global variable cpuset_being_rebound. + * It's ok if we rebind the same mm twice; mpol_rebind_mm() + * is idempotent. Also migrate pages in each mm to new nodes. + */ + migrate = is_memory_migrate(cs); + for (i = 0; i < n; i++) { + struct mm_struct *mm = mmarray[i]; + + mpol_rebind_mm(mm, &cs->mems_allowed); + if (migrate) { + do_migrate_pages(mm, &oldmem, &cs->mems_allowed, + MPOL_MF_MOVE_ALL); + } + mmput(mm); + } + + /* We're done rebinding vma's to this cpusets new mems_allowed. */ + kfree(mmarray); + set_cpuset_being_rebound(NULL); + retval = 0; +done: return retval; } /* + * Call with manage_sem held. + */ + +static int update_memory_pressure_enabled(struct cpuset *cs, char *buf) +{ + if (simple_strtoul(buf, NULL, 10) != 0) + cpuset_memory_pressure_enabled = 1; + else + cpuset_memory_pressure_enabled = 0; + return 0; +} + +/* * update_flag - read a 0 or a 1 in a file and update associated flag * bit: the bit to update (CS_CPU_EXCLUSIVE, CS_MEM_EXCLUSIVE, - * CS_NOTIFY_ON_RELEASE) + * CS_NOTIFY_ON_RELEASE, CS_MEMORY_MIGRATE) * cs: the cpuset to update * buf: the buffer where we read the 0 or 1 * @@ -834,6 +1002,104 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, char *buf) } /* + * Frequency meter - How fast is some event occuring? + * + * These routines manage a digitally filtered, constant time based, + * event frequency meter. There are four routines: + * fmeter_init() - initialize a frequency meter. + * fmeter_markevent() - called each time the event happens. + * fmeter_getrate() - returns the recent rate of such events. + * fmeter_update() - internal routine used to update fmeter. + * + * A common data structure is passed to each of these routines, + * which is used to keep track of the state required to manage the + * frequency meter and its digital filter. + * + * The filter works on the number of events marked per unit time. + * The filter is single-pole low-pass recursive (IIR). The time unit + * is 1 second. Arithmetic is done using 32-bit integers scaled to + * simulate 3 decimal digits of precision (multiplied by 1000). + * + * With an FM_COEF of 933, and a time base of 1 second, the filter + * has a half-life of 10 seconds, meaning that if the events quit + * happening, then the rate returned from the fmeter_getrate() + * will be cut in half each 10 seconds, until it converges to zero. + * + * It is not worth doing a real infinitely recursive filter. If more + * than FM_MAXTICKS ticks have elapsed since the last filter event, + * just compute FM_MAXTICKS ticks worth, by which point the level + * will be stable. + * + * Limit the count of unprocessed events to FM_MAXCNT, so as to avoid + * arithmetic overflow in the fmeter_update() routine. + * + * Given the simple 32 bit integer arithmetic used, this meter works + * best for reporting rates between one per millisecond (msec) and + * one per 32 (approx) seconds. At constant rates faster than one + * per msec it maxes out at values just under 1,000,000. At constant + * rates between one per msec, and one per second it will stabilize + * to a value N*1000, where N is the rate of events per second. + * At constant rates between one per second and one per 32 seconds, + * it will be choppy, moving up on the seconds that have an event, + * and then decaying until the next event. At rates slower than + * about one in 32 seconds, it decays all the way back to zero between + * each event. + */ + +#define FM_COEF 933 /* coefficient for half-life of 10 secs */ +#define FM_MAXTICKS ((time_t)99) /* useless computing more ticks than this */ +#define FM_MAXCNT 1000000 /* limit cnt to avoid overflow */ +#define FM_SCALE 1000 /* faux fixed point scale */ + +/* Initialize a frequency meter */ +static void fmeter_init(struct fmeter *fmp) +{ + fmp->cnt = 0; + fmp->val = 0; + fmp->time = 0; + spin_lock_init(&fmp->lock); +} + +/* Internal meter update - process cnt events and update value */ +static void fmeter_update(struct fmeter *fmp) +{ + time_t now = get_seconds(); + time_t ticks = now - fmp->time; + + if (ticks == 0) + return; + + ticks = min(FM_MAXTICKS, ticks); + while (ticks-- > 0) + fmp->val = (FM_COEF * fmp->val) / FM_SCALE; + fmp->time = now; + + fmp->val += ((FM_SCALE - FM_COEF) * fmp->cnt) / FM_SCALE; + fmp->cnt = 0; +} + +/* Process any previous ticks, then bump cnt by one (times scale). */ +static void fmeter_markevent(struct fmeter *fmp) +{ + spin_lock(&fmp->lock); + fmeter_update(fmp); + fmp->cnt = min(FM_MAXCNT, fmp->cnt + FM_SCALE); + spin_unlock(&fmp->lock); +} + +/* Process any previous ticks, then return current value. */ +static int fmeter_getrate(struct fmeter *fmp) +{ + int val; + + spin_lock(&fmp->lock); + fmeter_update(fmp); + val = fmp->val; + spin_unlock(&fmp->lock); + return val; +} + +/* * Attack task specified by pid in 'pidbuf' to cpuset 'cs', possibly * writing the path of the old cpuset in 'ppathbuf' if it needs to be * notified on release. @@ -848,6 +1114,8 @@ static int attach_task(struct cpuset *cs, char *pidbuf, char **ppathbuf) struct task_struct *tsk; struct cpuset *oldcs; cpumask_t cpus; + nodemask_t from, to; + struct mm_struct *mm; if (sscanf(pidbuf, "%d", &pid) != 1) return -EIO; @@ -887,14 +1155,27 @@ static int attach_task(struct cpuset *cs, char *pidbuf, char **ppathbuf) return -ESRCH; } atomic_inc(&cs->count); - tsk->cpuset = cs; + rcu_assign_pointer(tsk->cpuset, cs); task_unlock(tsk); guarantee_online_cpus(cs, &cpus); set_cpus_allowed(tsk, cpus); + from = oldcs->mems_allowed; + to = cs->mems_allowed; + up(&callback_sem); + + mm = get_task_mm(tsk); + if (mm) { + mpol_rebind_mm(mm, &to); + mmput(mm); + } + + if (is_memory_migrate(cs)) + do_migrate_pages(tsk->mm, &from, &to, MPOL_MF_MOVE_ALL); put_task_struct(tsk); + synchronize_rcu(); if (atomic_dec_and_test(&oldcs->count)) check_for_release(oldcs, ppathbuf); return 0; @@ -905,11 +1186,14 @@ static int attach_task(struct cpuset *cs, char *pidbuf, char **ppathbuf) typedef enum { FILE_ROOT, FILE_DIR, + FILE_MEMORY_MIGRATE, FILE_CPULIST, FILE_MEMLIST, FILE_CPU_EXCLUSIVE, FILE_MEM_EXCLUSIVE, FILE_NOTIFY_ON_RELEASE, + FILE_MEMORY_PRESSURE_ENABLED, + FILE_MEMORY_PRESSURE, FILE_TASKLIST, } cpuset_filetype_t; @@ -960,6 +1244,15 @@ static ssize_t cpuset_common_file_write(struct file *file, const char __user *us case FILE_NOTIFY_ON_RELEASE: retval = update_flag(CS_NOTIFY_ON_RELEASE, cs, buffer); break; + case FILE_MEMORY_MIGRATE: + retval = update_flag(CS_MEMORY_MIGRATE, cs, buffer); + break; + case FILE_MEMORY_PRESSURE_ENABLED: + retval = update_memory_pressure_enabled(cs, buffer); + break; + case FILE_MEMORY_PRESSURE: + retval = -EACCES; + break; case FILE_TASKLIST: retval = attach_task(cs, buffer, &pathbuf); break; @@ -1060,6 +1353,15 @@ static ssize_t cpuset_common_file_read(struct file *file, char __user *buf, case FILE_NOTIFY_ON_RELEASE: *s++ = notify_on_release(cs) ? '1' : '0'; break; + case FILE_MEMORY_MIGRATE: + *s++ = is_memory_migrate(cs) ? '1' : '0'; + break; + case FILE_MEMORY_PRESSURE_ENABLED: + *s++ = cpuset_memory_pressure_enabled ? '1' : '0'; + break; + case FILE_MEMORY_PRESSURE: + s += sprintf(s, "%d", fmeter_getrate(&cs->fmeter)); + break; default: retval = -EINVAL; goto out; @@ -1178,7 +1480,7 @@ static int cpuset_create_file(struct dentry *dentry, int mode) /* * cpuset_create_dir - create a directory for an object. - * cs: the cpuset we create the directory for. + * cs: the cpuset we create the directory for. * It must have a valid ->parent field * And we are going to fill its ->dentry field. * name: The name to give to the cpuset directory. Will be copied. @@ -1408,6 +1710,21 @@ static struct cftype cft_notify_on_release = { .private = FILE_NOTIFY_ON_RELEASE, }; +static struct cftype cft_memory_migrate = { + .name = "memory_migrate", + .private = FILE_MEMORY_MIGRATE, +}; + +static struct cftype cft_memory_pressure_enabled = { + .name = "memory_pressure_enabled", + .private = FILE_MEMORY_PRESSURE_ENABLED, +}; + +static struct cftype cft_memory_pressure = { + .name = "memory_pressure", + .private = FILE_MEMORY_PRESSURE, +}; + static int cpuset_populate_dir(struct dentry *cs_dentry) { int err; @@ -1422,6 +1739,10 @@ static int cpuset_populate_dir(struct dentry *cs_dentry) return err; if ((err = cpuset_add_file(cs_dentry, &cft_notify_on_release)) < 0) return err; + if ((err = cpuset_add_file(cs_dentry, &cft_memory_migrate)) < 0) + return err; + if ((err = cpuset_add_file(cs_dentry, &cft_memory_pressure)) < 0) + return err; if ((err = cpuset_add_file(cs_dentry, &cft_tasks)) < 0) return err; return 0; @@ -1446,7 +1767,7 @@ static long cpuset_create(struct cpuset *parent, const char *name, int mode) return -ENOMEM; down(&manage_sem); - refresh_mems(); + cpuset_update_task_memory_state(); cs->flags = 0; if (notify_on_release(parent)) set_bit(CS_NOTIFY_ON_RELEASE, &cs->flags); @@ -1457,11 +1778,13 @@ static long cpuset_create(struct cpuset *parent, const char *name, int mode) INIT_LIST_HEAD(&cs->children); atomic_inc(&cpuset_mems_generation); cs->mems_generation = atomic_read(&cpuset_mems_generation); + fmeter_init(&cs->fmeter); cs->parent = parent; down(&callback_sem); list_add(&cs->sibling, &cs->parent->children); + number_of_cpusets++; up(&callback_sem); err = cpuset_create_dir(cs, name, mode); @@ -1503,7 +1826,7 @@ static int cpuset_rmdir(struct inode *unused_dir, struct dentry *dentry) /* the vfs holds both inode->i_sem already */ down(&manage_sem); - refresh_mems(); + cpuset_update_task_memory_state(); if (atomic_read(&cs->count) > 0) { up(&manage_sem); return -EBUSY; @@ -1524,6 +1847,7 @@ static int cpuset_rmdir(struct inode *unused_dir, struct dentry *dentry) spin_unlock(&d->d_lock); cpuset_d_remove_dir(d); dput(d); + number_of_cpusets--; up(&callback_sem); if (list_empty(&parent->children)) check_for_release(parent, &pathbuf); @@ -1532,6 +1856,21 @@ static int cpuset_rmdir(struct inode *unused_dir, struct dentry *dentry) return 0; } +/* + * cpuset_init_early - just enough so that the calls to + * cpuset_update_task_memory_state() in early init code + * are harmless. + */ + +int __init cpuset_init_early(void) +{ + struct task_struct *tsk = current; + + tsk->cpuset = &top_cpuset; + tsk->cpuset->mems_generation = atomic_read(&cpuset_mems_generation); + return 0; +} + /** * cpuset_init - initialize cpusets at system boot * @@ -1546,6 +1885,7 @@ int __init cpuset_init(void) top_cpuset.cpus_allowed = CPU_MASK_ALL; top_cpuset.mems_allowed = NODE_MASK_ALL; + fmeter_init(&top_cpuset.fmeter); atomic_inc(&cpuset_mems_generation); top_cpuset.mems_generation = atomic_read(&cpuset_mems_generation); @@ -1566,7 +1906,11 @@ int __init cpuset_init(void) root->d_inode->i_nlink++; top_cpuset.dentry = root; root->d_inode->i_op = &cpuset_dir_inode_operations; + number_of_cpusets = 1; err = cpuset_populate_dir(root); + /* memory_pressure_enabled is in root cpuset only */ + if (err == 0) + err = cpuset_add_file(root, &cft_memory_pressure_enabled); out: return err; } @@ -1632,15 +1976,13 @@ void cpuset_fork(struct task_struct *child) * * We don't need to task_lock() this reference to tsk->cpuset, * because tsk is already marked PF_EXITING, so attach_task() won't - * mess with it. + * mess with it, or task is a failed fork, never visible to attach_task. **/ void cpuset_exit(struct task_struct *tsk) { struct cpuset *cs; - BUG_ON(!(tsk->flags & PF_EXITING)); - cs = tsk->cpuset; tsk->cpuset = NULL; @@ -1667,14 +2009,14 @@ void cpuset_exit(struct task_struct *tsk) * tasks cpuset. **/ -cpumask_t cpuset_cpus_allowed(const struct task_struct *tsk) +cpumask_t cpuset_cpus_allowed(struct task_struct *tsk) { cpumask_t mask; down(&callback_sem); - task_lock((struct task_struct *)tsk); + task_lock(tsk); guarantee_online_cpus(tsk->cpuset, &mask); - task_unlock((struct task_struct *)tsk); + task_unlock(tsk); up(&callback_sem); return mask; @@ -1686,43 +2028,26 @@ void cpuset_init_current_mems_allowed(void) } /** - * cpuset_update_current_mems_allowed - update mems parameters to new values - * - * If the current tasks cpusets mems_allowed changed behind our backs, - * update current->mems_allowed and mems_generation to the new value. - * Do not call this routine if in_interrupt(). + * cpuset_mems_allowed - return mems_allowed mask from a tasks cpuset. + * @tsk: pointer to task_struct from which to obtain cpuset->mems_allowed. * - * Call without callback_sem or task_lock() held. May be called - * with or without manage_sem held. Unless exiting, it will acquire - * task_lock(). Also might acquire callback_sem during call to - * refresh_mems(). - */ + * Description: Returns the nodemask_t mems_allowed of the cpuset + * attached to the specified @tsk. Guaranteed to return some non-empty + * subset of node_online_map, even if this means going outside the + * tasks cpuset. + **/ -void cpuset_update_current_mems_allowed(void) +nodemask_t cpuset_mems_allowed(struct task_struct *tsk) { - struct cpuset *cs; - int need_to_refresh = 0; + nodemask_t mask; - task_lock(current); - cs = current->cpuset; - if (!cs) - goto done; - if (current->cpuset_mems_generation != cs->mems_generation) - need_to_refresh = 1; -done: - task_unlock(current); - if (need_to_refresh) - refresh_mems(); -} + down(&callback_sem); + task_lock(tsk); + guarantee_online_mems(tsk->cpuset, &mask); + task_unlock(tsk); + up(&callback_sem); -/** - * cpuset_restrict_to_mems_allowed - limit nodes to current mems_allowed - * @nodes: pointer to a node bitmap that is and-ed with mems_allowed - */ -void cpuset_restrict_to_mems_allowed(unsigned long *nodes) -{ - bitmap_and(nodes, nodes, nodes_addr(current->mems_allowed), - MAX_NUMNODES); + return mask; } /** @@ -1795,7 +2120,7 @@ static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs) * GFP_USER - only nodes in current tasks mems allowed ok. **/ -int cpuset_zone_allowed(struct zone *z, gfp_t gfp_mask) +int __cpuset_zone_allowed(struct zone *z, gfp_t gfp_mask) { int node; /* node that zone z is on */ const struct cpuset *cs; /* current cpuset ancestors */ @@ -1867,6 +2192,42 @@ done: } /* + * Collection of memory_pressure is suppressed unless + * this flag is enabled by writing "1" to the special + * cpuset file 'memory_pressure_enabled' in the root cpuset. + */ + +int cpuset_memory_pressure_enabled __read_mostly; + +/** + * cpuset_memory_pressure_bump - keep stats of per-cpuset reclaims. + * + * Keep a running average of the rate of synchronous (direct) + * page reclaim efforts initiated by tasks in each cpuset. + * + * This represents the rate at which some task in the cpuset + * ran low on memory on all nodes it was allowed to use, and + * had to enter the kernels page reclaim code in an effort to + * create more free memory by tossing clean pages or swapping + * or writing dirty pages. + * + * Display to user space in the per-cpuset read-only file + * "memory_pressure". Value displayed is an integer + * representing the recent rate of entry into the synchronous + * (direct) page reclaim by any task attached to the cpuset. + **/ + +void __cpuset_memory_pressure_bump(void) +{ + struct cpuset *cs; + + task_lock(current); + cs = current->cpuset; + fmeter_markevent(&cs->fmeter); + task_unlock(current); +} + +/* * proc_cpuset_show() * - Print tasks cpuset path into seq_file. * - Used for /proc/<pid>/cpuset. diff --git a/kernel/exit.c b/kernel/exit.c index ee515683b92..caceabf3f23 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -72,7 +72,6 @@ repeat: __ptrace_unlink(p); BUG_ON(!list_empty(&p->ptrace_list) || !list_empty(&p->ptrace_children)); __exit_signal(p); - __exit_sighand(p); /* * Note that the fastpath in sys_times depends on __exit_signal having * updated the counters before a task is removed from the tasklist of @@ -258,7 +257,7 @@ static inline void reparent_to_init(void) void __set_special_pids(pid_t session, pid_t pgrp) { - struct task_struct *curr = current; + struct task_struct *curr = current->group_leader; if (curr->signal->session != session) { detach_pid(curr, PIDTYPE_SID); @@ -926,7 +925,6 @@ do_group_exit(int exit_code) /* Another thread got here before we took the lock. */ exit_code = sig->group_exit_code; else { - sig->flags = SIGNAL_GROUP_EXIT; sig->group_exit_code = exit_code; zap_other_threads(current); } diff --git a/kernel/fork.c b/kernel/fork.c index fb8572a4229..72e3252c676 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -743,6 +743,14 @@ int unshare_files(void) EXPORT_SYMBOL(unshare_files); +void sighand_free_cb(struct rcu_head *rhp) +{ + struct sighand_struct *sp; + + sp = container_of(rhp, struct sighand_struct, rcu); + kmem_cache_free(sighand_cachep, sp); +} + static inline int copy_sighand(unsigned long clone_flags, struct task_struct * tsk) { struct sighand_struct *sig; @@ -752,7 +760,7 @@ static inline int copy_sighand(unsigned long clone_flags, struct task_struct * t return 0; } sig = kmem_cache_alloc(sighand_cachep, GFP_KERNEL); - tsk->sighand = sig; + rcu_assign_pointer(tsk->sighand, sig); if (!sig) return -ENOMEM; spin_lock_init(&sig->siglock); @@ -803,9 +811,6 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts sig->it_prof_expires = cputime_zero; sig->it_prof_incr = cputime_zero; - sig->tty = current->signal->tty; - sig->pgrp = process_group(current); - sig->session = current->signal->session; sig->leader = 0; /* session leadership doesn't inherit */ sig->tty_old_pgrp = 0; @@ -964,12 +969,13 @@ static task_t *copy_process(unsigned long clone_flags, p->io_context = NULL; p->io_wait = NULL; p->audit_context = NULL; + cpuset_fork(p); #ifdef CONFIG_NUMA p->mempolicy = mpol_copy(p->mempolicy); if (IS_ERR(p->mempolicy)) { retval = PTR_ERR(p->mempolicy); p->mempolicy = NULL; - goto bad_fork_cleanup; + goto bad_fork_cleanup_cpuset; } #endif @@ -1127,25 +1133,19 @@ static task_t *copy_process(unsigned long clone_flags, attach_pid(p, PIDTYPE_PID, p->pid); attach_pid(p, PIDTYPE_TGID, p->tgid); if (thread_group_leader(p)) { + p->signal->tty = current->signal->tty; + p->signal->pgrp = process_group(current); + p->signal->session = current->signal->session; attach_pid(p, PIDTYPE_PGID, process_group(p)); attach_pid(p, PIDTYPE_SID, p->signal->session); if (p->pid) __get_cpu_var(process_counts)++; } - if (!current->signal->tty && p->signal->tty) - p->signal->tty = NULL; - nr_threads++; total_forks++; write_unlock_irq(&tasklist_lock); proc_fork_connector(p); - cpuset_fork(p); - retval = 0; - -fork_out: - if (retval) - return ERR_PTR(retval); return p; bad_fork_cleanup_namespace: @@ -1172,7 +1172,9 @@ bad_fork_cleanup_security: bad_fork_cleanup_policy: #ifdef CONFIG_NUMA mpol_free(p->mempolicy); +bad_fork_cleanup_cpuset: #endif + cpuset_exit(p); bad_fork_cleanup: if (p->binfmt) module_put(p->binfmt->module); @@ -1184,7 +1186,8 @@ bad_fork_cleanup_count: free_uid(p->user); bad_fork_free: free_task(p); - goto fork_out; +fork_out: + return ERR_PTR(retval); } struct pt_regs * __devinit __attribute__((weak)) idle_regs(struct pt_regs *regs) diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 8a64a4844cd..d03b5eef8ce 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -10,6 +10,8 @@ #include <linux/proc_fs.h> #include <linux/interrupt.h> +#include "internals.h" + static struct proc_dir_entry *root_irq_dir, *irq_dir[NR_IRQS]; #ifdef CONFIG_SMP diff --git a/kernel/module.c b/kernel/module.c index 4b06bbad49c..e4276046a1b 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -496,15 +496,15 @@ static void module_unload_free(struct module *mod) } #ifdef CONFIG_MODULE_FORCE_UNLOAD -static inline int try_force(unsigned int flags) +static inline int try_force_unload(unsigned int flags) { int ret = (flags & O_TRUNC); if (ret) - add_taint(TAINT_FORCED_MODULE); + add_taint(TAINT_FORCED_RMMOD); return ret; } #else -static inline int try_force(unsigned int flags) +static inline int try_force_unload(unsigned int flags) { return 0; } @@ -524,7 +524,7 @@ static int __try_stop_module(void *_sref) /* If it's not unused, quit unless we are told to block. */ if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) { - if (!(*sref->forced = try_force(sref->flags))) + if (!(*sref->forced = try_force_unload(sref->flags))) return -EWOULDBLOCK; } @@ -609,7 +609,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags) /* If it has an init func, it must have an exit func to unload */ if ((mod->init != NULL && mod->exit == NULL) || mod->unsafe) { - forced = try_force(flags); + forced = try_force_unload(flags); if (!forced) { /* This module can't be removed */ ret = -EBUSY; @@ -958,7 +958,6 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, unsigned long ret; const unsigned long *crc; - spin_lock_irq(&modlist_lock); ret = __find_symbol(name, &owner, &crc, mod->license_gplok); if (ret) { /* use_module can fail due to OOM, or module unloading */ @@ -966,7 +965,6 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, !use_module(mod, owner)) ret = 0; } - spin_unlock_irq(&modlist_lock); return ret; } @@ -1204,6 +1202,39 @@ void *__symbol_get(const char *symbol) } EXPORT_SYMBOL_GPL(__symbol_get); +/* + * Ensure that an exported symbol [global namespace] does not already exist + * in the Kernel or in some other modules exported symbol table. + */ +static int verify_export_symbols(struct module *mod) +{ + const char *name = NULL; + unsigned long i, ret = 0; + struct module *owner; + const unsigned long *crc; + + for (i = 0; i < mod->num_syms; i++) + if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) { + name = mod->syms[i].name; + ret = -ENOEXEC; + goto dup; + } + + for (i = 0; i < mod->num_gpl_syms; i++) + if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) { + name = mod->gpl_syms[i].name; + ret = -ENOEXEC; + goto dup; + } + +dup: + if (ret) + printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n", + mod->name, name, module_name(owner)); + + return ret; +} + /* Change all symbols so that sh_value encodes the pointer directly. */ static int simplify_symbols(Elf_Shdr *sechdrs, unsigned int symindex, @@ -1715,6 +1746,11 @@ static struct module *load_module(void __user *umod, /* Set up license info based on the info section */ set_license(mod, get_modinfo(sechdrs, infoindex, "license")); + if (strcmp(mod->name, "ndiswrapper") == 0) + add_taint(TAINT_PROPRIETARY_MODULE); + if (strcmp(mod->name, "driverloader") == 0) + add_taint(TAINT_PROPRIETARY_MODULE); + #ifdef CONFIG_MODULE_UNLOAD /* Set up MODINFO_ATTR fields */ setup_modinfo(mod, sechdrs, infoindex); @@ -1767,6 +1803,12 @@ static struct module *load_module(void __user *umod, goto cleanup; } + /* Find duplicate symbols */ + err = verify_export_symbols(mod); + + if (err < 0) + goto cleanup; + /* Set up and sort exception table */ mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable); mod->extable = extable = (void *)sechdrs[exindex].sh_addr; diff --git a/kernel/pid.c b/kernel/pid.c index edba31c681a..1acc0724699 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -136,7 +136,7 @@ struct pid * fastcall find_pid(enum pid_type type, int nr) struct hlist_node *elem; struct pid *pid; - hlist_for_each_entry(pid, elem, + hlist_for_each_entry_rcu(pid, elem, &pid_hash[type][pid_hashfn(nr)], pid_chain) { if (pid->nr == nr) return pid; @@ -150,15 +150,15 @@ int fastcall attach_pid(task_t *task, enum pid_type type, int nr) task_pid = &task->pids[type]; pid = find_pid(type, nr); + task_pid->nr = nr; if (pid == NULL) { - hlist_add_head(&task_pid->pid_chain, - &pid_hash[type][pid_hashfn(nr)]); INIT_LIST_HEAD(&task_pid->pid_list); + hlist_add_head_rcu(&task_pid->pid_chain, + &pid_hash[type][pid_hashfn(nr)]); } else { INIT_HLIST_NODE(&task_pid->pid_chain); - list_add_tail(&task_pid->pid_list, &pid->pid_list); + list_add_tail_rcu(&task_pid->pid_list, &pid->pid_list); } - task_pid->nr = nr; return 0; } @@ -170,20 +170,20 @@ static fastcall int __detach_pid(task_t *task, enum pid_type type) pid = &task->pids[type]; if (!hlist_unhashed(&pid->pid_chain)) { - hlist_del(&pid->pid_chain); - if (list_empty(&pid->pid_list)) + if (list_empty(&pid->pid_list)) { nr = pid->nr; - else { + hlist_del_rcu(&pid->pid_chain); + } else { pid_next = list_entry(pid->pid_list.next, struct pid, pid_list); /* insert next pid from pid_list to hash */ - hlist_add_head(&pid_next->pid_chain, - &pid_hash[type][pid_hashfn(pid_next->nr)]); + hlist_replace_rcu(&pid->pid_chain, + &pid_next->pid_chain); } } - list_del(&pid->pid_list); + list_del_rcu(&pid->pid_list); pid->nr = 0; return nr; diff --git a/kernel/printk.c b/kernel/printk.c index 5287be83e3e..2251be80cd2 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -569,7 +569,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) p[1] <= '7' && p[2] == '>') { loglev_char = p[1]; p += 3; - printed_len += 3; + printed_len -= 3; } else { loglev_char = default_message_loglevel + '0'; @@ -584,7 +584,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) for (tp = tbuf; tp < tbuf + tlen; tp++) emit_log_char(*tp); - printed_len += tlen - 3; + printed_len += tlen; } else { if (p[0] != '<' || p[1] < '0' || p[1] > '7' || p[2] != '>') { @@ -592,8 +592,8 @@ asmlinkage int vprintk(const char *fmt, va_list args) emit_log_char(default_message_loglevel + '0'); emit_log_char('>'); + printed_len += 3; } - printed_len += 3; } log_level_unknown = 0; if (!*p) diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 656476eedb1..cceaf09ac41 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -408,54 +408,62 @@ int ptrace_request(struct task_struct *child, long request, return ret; } -#ifndef __ARCH_SYS_PTRACE -static int ptrace_get_task_struct(long request, long pid, - struct task_struct **childp) +/** + * ptrace_traceme -- helper for PTRACE_TRACEME + * + * Performs checks and sets PT_PTRACED. + * Should be used by all ptrace implementations for PTRACE_TRACEME. + */ +int ptrace_traceme(void) { - struct task_struct *child; int ret; /* - * Callers use child == NULL as an indication to exit early even - * when the return value is 0, so make sure it is non-NULL here. + * Are we already being traced? + */ + if (current->ptrace & PT_PTRACED) + return -EPERM; + ret = security_ptrace(current->parent, current); + if (ret) + return -EPERM; + /* + * Set the ptrace bit in the process ptrace flags. */ - *childp = NULL; + current->ptrace |= PT_PTRACED; + return 0; +} - if (request == PTRACE_TRACEME) { - /* - * Are we already being traced? - */ - if (current->ptrace & PT_PTRACED) - return -EPERM; - ret = security_ptrace(current->parent, current); - if (ret) - return -EPERM; - /* - * Set the ptrace bit in the process ptrace flags. - */ - current->ptrace |= PT_PTRACED; - return 0; - } +/** + * ptrace_get_task_struct -- grab a task struct reference for ptrace + * @pid: process id to grab a task_struct reference of + * + * This function is a helper for ptrace implementations. It checks + * permissions and then grabs a task struct for use of the actual + * ptrace implementation. + * + * Returns the task_struct for @pid or an ERR_PTR() on failure. + */ +struct task_struct *ptrace_get_task_struct(pid_t pid) +{ + struct task_struct *child; /* - * You may not mess with init + * Tracing init is not allowed. */ if (pid == 1) - return -EPERM; + return ERR_PTR(-EPERM); - ret = -ESRCH; read_lock(&tasklist_lock); child = find_task_by_pid(pid); if (child) get_task_struct(child); read_unlock(&tasklist_lock); if (!child) - return -ESRCH; - - *childp = child; - return 0; + return ERR_PTR(-ESRCH); + return child; } +#ifndef __ARCH_SYS_PTRACE asmlinkage long sys_ptrace(long request, long pid, long addr, long data) { struct task_struct *child; @@ -465,9 +473,16 @@ asmlinkage long sys_ptrace(long request, long pid, long addr, long data) * This lock_kernel fixes a subtle race with suid exec */ lock_kernel(); - ret = ptrace_get_task_struct(request, pid, &child); - if (!child) + if (request == PTRACE_TRACEME) { + ret = ptrace_traceme(); goto out; + } + + child = ptrace_get_task_struct(pid); + if (IS_ERR(child)) { + ret = PTR_ERR(child); + goto out; + } if (request == PTRACE_ATTACH) { ret = ptrace_attach(child); diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index 48d3bce465b..30b0bba0385 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -35,6 +35,7 @@ #include <linux/init.h> #include <linux/spinlock.h> #include <linux/smp.h> +#include <linux/rcupdate.h> #include <linux/interrupt.h> #include <linux/sched.h> #include <asm/atomic.h> @@ -45,7 +46,6 @@ #include <linux/percpu.h> #include <linux/notifier.h> #include <linux/rcupdate.h> -#include <linux/rcuref.h> #include <linux/cpu.h> /* Definition for rcupdate control block. */ @@ -61,9 +61,9 @@ struct rcu_state { /* for current batch to proceed. */ }; -static struct rcu_state rcu_state ____cacheline_maxaligned_in_smp = +static struct rcu_state rcu_state ____cacheline_internodealigned_in_smp = {.lock = SPIN_LOCK_UNLOCKED, .cpumask = CPU_MASK_NONE }; -static struct rcu_state rcu_bh_state ____cacheline_maxaligned_in_smp = +static struct rcu_state rcu_bh_state ____cacheline_internodealigned_in_smp = {.lock = SPIN_LOCK_UNLOCKED, .cpumask = CPU_MASK_NONE }; DEFINE_PER_CPU(struct rcu_data, rcu_data) = { 0L }; @@ -73,19 +73,6 @@ DEFINE_PER_CPU(struct rcu_data, rcu_bh_data) = { 0L }; static DEFINE_PER_CPU(struct tasklet_struct, rcu_tasklet) = {NULL}; static int maxbatch = 10000; -#ifndef __HAVE_ARCH_CMPXCHG -/* - * We use an array of spinlocks for the rcurefs -- similar to ones in sparc - * 32 bit atomic_t implementations, and a hash function similar to that - * for our refcounting needs. - * Can't help multiprocessors which donot have cmpxchg :( - */ - -spinlock_t __rcuref_hash[RCUREF_HASH_SIZE] = { - [0 ... (RCUREF_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED -}; -#endif - /** * call_rcu - Queue an RCU callback for invocation after a grace period. * @head: structure to be used for queueing the RCU updates. diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 49fbbeff201..773219907dd 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -39,7 +39,6 @@ #include <linux/moduleparam.h> #include <linux/percpu.h> #include <linux/notifier.h> -#include <linux/rcuref.h> #include <linux/cpu.h> #include <linux/random.h> #include <linux/delay.h> @@ -49,9 +48,11 @@ MODULE_LICENSE("GPL"); static int nreaders = -1; /* # reader threads, defaults to 4*ncpus */ -static int stat_interval = 0; /* Interval between stats, in seconds. */ +static int stat_interval; /* Interval between stats, in seconds. */ /* Defaults to "only at end of test". */ -static int verbose = 0; /* Print more debug info. */ +static int verbose; /* Print more debug info. */ +static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ +static int shuffle_interval = 5; /* Interval between shuffles (in sec)*/ MODULE_PARM(nreaders, "i"); MODULE_PARM_DESC(nreaders, "Number of RCU reader threads"); @@ -59,6 +60,10 @@ MODULE_PARM(stat_interval, "i"); MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s"); MODULE_PARM(verbose, "i"); MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s"); +MODULE_PARM(test_no_idle_hz, "i"); +MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs"); +MODULE_PARM(shuffle_interval, "i"); +MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles"); #define TORTURE_FLAG "rcutorture: " #define PRINTK_STRING(s) \ do { printk(KERN_ALERT TORTURE_FLAG s "\n"); } while (0) @@ -73,6 +78,7 @@ static int nrealreaders; static struct task_struct *writer_task; static struct task_struct **reader_tasks; static struct task_struct *stats_task; +static struct task_struct *shuffler_task; #define RCU_TORTURE_PIPE_LEN 10 @@ -103,7 +109,7 @@ atomic_t n_rcu_torture_error; /* * Allocate an element from the rcu_tortures pool. */ -struct rcu_torture * +static struct rcu_torture * rcu_torture_alloc(void) { struct list_head *p; @@ -376,12 +382,77 @@ rcu_torture_stats(void *arg) return 0; } +static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ + +/* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case + * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. + */ +void rcu_torture_shuffle_tasks(void) +{ + cpumask_t tmp_mask = CPU_MASK_ALL; + int i; + + lock_cpu_hotplug(); + + /* No point in shuffling if there is only one online CPU (ex: UP) */ + if (num_online_cpus() == 1) { + unlock_cpu_hotplug(); + return; + } + + if (rcu_idle_cpu != -1) + cpu_clear(rcu_idle_cpu, tmp_mask); + + set_cpus_allowed(current, tmp_mask); + + if (reader_tasks != NULL) { + for (i = 0; i < nrealreaders; i++) + if (reader_tasks[i]) + set_cpus_allowed(reader_tasks[i], tmp_mask); + } + + if (writer_task) + set_cpus_allowed(writer_task, tmp_mask); + + if (stats_task) + set_cpus_allowed(stats_task, tmp_mask); + + if (rcu_idle_cpu == -1) + rcu_idle_cpu = num_online_cpus() - 1; + else + rcu_idle_cpu--; + + unlock_cpu_hotplug(); +} + +/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the + * system to become idle at a time and cut off its timer ticks. This is meant + * to test the support for such tickless idle CPU in RCU. + */ +static int +rcu_torture_shuffle(void *arg) +{ + VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); + do { + schedule_timeout_interruptible(shuffle_interval * HZ); + rcu_torture_shuffle_tasks(); + } while (!kthread_should_stop()); + VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); + return 0; +} + static void rcu_torture_cleanup(void) { int i; fullstop = 1; + if (shuffler_task != NULL) { + VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); + kthread_stop(shuffler_task); + } + shuffler_task = NULL; + if (writer_task != NULL) { VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); kthread_stop(writer_task); @@ -430,9 +501,11 @@ rcu_torture_init(void) nrealreaders = nreaders; else nrealreaders = 2 * num_online_cpus(); - printk(KERN_ALERT TORTURE_FLAG - "--- Start of test: nreaders=%d stat_interval=%d verbose=%d\n", - nrealreaders, stat_interval, verbose); + printk(KERN_ALERT TORTURE_FLAG "--- Start of test: nreaders=%d " + "stat_interval=%d verbose=%d test_no_idle_hz=%d " + "shuffle_interval = %d\n", + nrealreaders, stat_interval, verbose, test_no_idle_hz, + shuffle_interval); fullstop = 0; /* Set up the freelist. */ @@ -502,6 +575,18 @@ rcu_torture_init(void) goto unwind; } } + if (test_no_idle_hz) { + rcu_idle_cpu = num_online_cpus() - 1; + /* Create the shuffler thread */ + shuffler_task = kthread_run(rcu_torture_shuffle, NULL, + "rcu_torture_shuffle"); + if (IS_ERR(shuffler_task)) { + firsterr = PTR_ERR(shuffler_task); + VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); + shuffler_task = NULL; + goto unwind; + } + } return 0; unwind: diff --git a/kernel/sched.c b/kernel/sched.c index 6f46c94cc29..92733091154 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -176,6 +176,13 @@ static unsigned int task_timeslice(task_t *p) #define task_hot(p, now, sd) ((long long) ((now) - (p)->last_ran) \ < (long long) (sd)->cache_hot_time) +void __put_task_struct_cb(struct rcu_head *rhp) +{ + __put_task_struct(container_of(rhp, struct task_struct, rcu)); +} + +EXPORT_SYMBOL_GPL(__put_task_struct_cb); + /* * These are the runqueue data structures: */ diff --git a/kernel/signal.c b/kernel/signal.c index d7611f189ef..08aa5b263f3 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -329,13 +329,20 @@ void __exit_sighand(struct task_struct *tsk) /* Ok, we're done with the signal handlers */ tsk->sighand = NULL; if (atomic_dec_and_test(&sighand->count)) - kmem_cache_free(sighand_cachep, sighand); + sighand_free(sighand); } void exit_sighand(struct task_struct *tsk) { write_lock_irq(&tasklist_lock); - __exit_sighand(tsk); + rcu_read_lock(); + if (tsk->sighand != NULL) { + struct sighand_struct *sighand = rcu_dereference(tsk->sighand); + spin_lock(&sighand->siglock); + __exit_sighand(tsk); + spin_unlock(&sighand->siglock); + } + rcu_read_unlock(); write_unlock_irq(&tasklist_lock); } @@ -345,19 +352,20 @@ void exit_sighand(struct task_struct *tsk) void __exit_signal(struct task_struct *tsk) { struct signal_struct * sig = tsk->signal; - struct sighand_struct * sighand = tsk->sighand; + struct sighand_struct * sighand; if (!sig) BUG(); if (!atomic_read(&sig->count)) BUG(); + rcu_read_lock(); + sighand = rcu_dereference(tsk->sighand); spin_lock(&sighand->siglock); posix_cpu_timers_exit(tsk); if (atomic_dec_and_test(&sig->count)) { posix_cpu_timers_exit_group(tsk); - if (tsk == sig->curr_target) - sig->curr_target = next_thread(tsk); tsk->signal = NULL; + __exit_sighand(tsk); spin_unlock(&sighand->siglock); flush_sigqueue(&sig->shared_pending); } else { @@ -389,9 +397,11 @@ void __exit_signal(struct task_struct *tsk) sig->nvcsw += tsk->nvcsw; sig->nivcsw += tsk->nivcsw; sig->sched_time += tsk->sched_time; + __exit_sighand(tsk); spin_unlock(&sighand->siglock); sig = NULL; /* Marker for below. */ } + rcu_read_unlock(); clear_tsk_thread_flag(tsk,TIF_SIGPENDING); flush_sigqueue(&tsk->pending); if (sig) { @@ -613,6 +623,33 @@ void signal_wake_up(struct task_struct *t, int resume) * Returns 1 if any signals were found. * * All callers must be holding the siglock. + * + * This version takes a sigset mask and looks at all signals, + * not just those in the first mask word. + */ +static int rm_from_queue_full(sigset_t *mask, struct sigpending *s) +{ + struct sigqueue *q, *n; + sigset_t m; + + sigandsets(&m, mask, &s->signal); + if (sigisemptyset(&m)) + return 0; + + signandsets(&s->signal, &s->signal, mask); + list_for_each_entry_safe(q, n, &s->list, list) { + if (sigismember(mask, q->info.si_signo)) { + list_del_init(&q->list); + __sigqueue_free(q); + } + } + return 1; +} +/* + * Remove signals in mask from the pending set and queue. + * Returns 1 if any signals were found. + * + * All callers must be holding the siglock. */ static int rm_from_queue(unsigned long mask, struct sigpending *s) { @@ -1080,18 +1117,29 @@ void zap_other_threads(struct task_struct *p) } /* - * Must be called with the tasklist_lock held for reading! + * Must be called under rcu_read_lock() or with tasklist_lock read-held. */ int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { unsigned long flags; + struct sighand_struct *sp; int ret; +retry: ret = check_kill_permission(sig, info, p); - if (!ret && sig && p->sighand) { - spin_lock_irqsave(&p->sighand->siglock, flags); + if (!ret && sig && (sp = rcu_dereference(p->sighand))) { + spin_lock_irqsave(&sp->siglock, flags); + if (p->sighand != sp) { + spin_unlock_irqrestore(&sp->siglock, flags); + goto retry; + } + if ((atomic_read(&sp->count) == 0) || + (atomic_read(&p->usage) == 0)) { + spin_unlock_irqrestore(&sp->siglock, flags); + return -ESRCH; + } ret = __group_send_sig_info(sig, info, p); - spin_unlock_irqrestore(&p->sighand->siglock, flags); + spin_unlock_irqrestore(&sp->siglock, flags); } return ret; @@ -1136,14 +1184,21 @@ int kill_proc_info(int sig, struct siginfo *info, pid_t pid) { int error; + int acquired_tasklist_lock = 0; struct task_struct *p; - read_lock(&tasklist_lock); + rcu_read_lock(); + if (unlikely(sig_kernel_stop(sig) || sig == SIGCONT)) { + read_lock(&tasklist_lock); + acquired_tasklist_lock = 1; + } p = find_task_by_pid(pid); error = -ESRCH; if (p) error = group_send_sig_info(sig, info, p); - read_unlock(&tasklist_lock); + if (unlikely(acquired_tasklist_lock)) + read_unlock(&tasklist_lock); + rcu_read_unlock(); return error; } @@ -1163,8 +1218,7 @@ int kill_proc_info_as_uid(int sig, struct siginfo *info, pid_t pid, ret = -ESRCH; goto out_unlock; } - if ((!info || ((unsigned long)info != 1 && - (unsigned long)info != 2 && SI_FROMUSER(info))) + if ((info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info))) && (euid != p->suid) && (euid != p->uid) && (uid != p->suid) && (uid != p->uid)) { ret = -EPERM; @@ -1355,16 +1409,54 @@ send_sigqueue(int sig, struct sigqueue *q, struct task_struct *p) { unsigned long flags; int ret = 0; + struct sighand_struct *sh; BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); - read_lock(&tasklist_lock); + + /* + * The rcu based delayed sighand destroy makes it possible to + * run this without tasklist lock held. The task struct itself + * cannot go away as create_timer did get_task_struct(). + * + * We return -1, when the task is marked exiting, so + * posix_timer_event can redirect it to the group leader + */ + rcu_read_lock(); if (unlikely(p->flags & PF_EXITING)) { ret = -1; goto out_err; } - spin_lock_irqsave(&p->sighand->siglock, flags); +retry: + sh = rcu_dereference(p->sighand); + + spin_lock_irqsave(&sh->siglock, flags); + if (p->sighand != sh) { + /* We raced with exec() in a multithreaded process... */ + spin_unlock_irqrestore(&sh->siglock, flags); + goto retry; + } + + /* + * We do the check here again to handle the following scenario: + * + * CPU 0 CPU 1 + * send_sigqueue + * check PF_EXITING + * interrupt exit code running + * __exit_signal + * lock sighand->siglock + * unlock sighand->siglock + * lock sh->siglock + * add(tsk->pending) flush_sigqueue(tsk->pending) + * + */ + + if (unlikely(p->flags & PF_EXITING)) { + ret = -1; + goto out; + } if (unlikely(!list_empty(&q->list))) { /* @@ -1388,9 +1480,9 @@ send_sigqueue(int sig, struct sigqueue *q, struct task_struct *p) signal_wake_up(p, sig == SIGKILL); out: - spin_unlock_irqrestore(&p->sighand->siglock, flags); + spin_unlock_irqrestore(&sh->siglock, flags); out_err: - read_unlock(&tasklist_lock); + rcu_read_unlock(); return ret; } @@ -1402,7 +1494,9 @@ send_group_sigqueue(int sig, struct sigqueue *q, struct task_struct *p) int ret = 0; BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); + read_lock(&tasklist_lock); + /* Since it_lock is held, p->sighand cannot be NULL. */ spin_lock_irqsave(&p->sighand->siglock, flags); handle_stop_signal(sig, p); @@ -1436,7 +1530,7 @@ send_group_sigqueue(int sig, struct sigqueue *q, struct task_struct *p) out: spin_unlock_irqrestore(&p->sighand->siglock, flags); read_unlock(&tasklist_lock); - return(ret); + return ret; } /* @@ -2338,6 +2432,7 @@ int do_sigaction(int sig, const struct k_sigaction *act, struct k_sigaction *oact) { struct k_sigaction *k; + sigset_t mask; if (!valid_signal(sig) || sig < 1 || (act && sig_kernel_only(sig))) return -EINVAL; @@ -2385,9 +2480,11 @@ do_sigaction(int sig, const struct k_sigaction *act, struct k_sigaction *oact) *k = *act; sigdelsetmask(&k->sa.sa_mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); - rm_from_queue(sigmask(sig), &t->signal->shared_pending); + sigemptyset(&mask); + sigaddset(&mask, sig); + rm_from_queue_full(&mask, &t->signal->shared_pending); do { - rm_from_queue(sigmask(sig), &t->pending); + rm_from_queue_full(&mask, &t->pending); recalc_sigpending_tsk(t); t = next_thread(t); } while (t != current); diff --git a/kernel/sys.c b/kernel/sys.c index eecf84526af..b6941e06d5d 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -489,6 +489,12 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user magic2 != LINUX_REBOOT_MAGIC2C)) return -EINVAL; + /* Instead of trying to make the power_off code look like + * halt when pm_power_off is not set do it the easy way. + */ + if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) + cmd = LINUX_REBOOT_CMD_HALT; + lock_kernel(); switch (cmd) { case LINUX_REBOOT_CMD_RESTART: @@ -1084,10 +1090,11 @@ asmlinkage long sys_times(struct tms __user * tbuf) asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) { struct task_struct *p; + struct task_struct *group_leader = current->group_leader; int err = -EINVAL; if (!pid) - pid = current->pid; + pid = group_leader->pid; if (!pgid) pgid = pid; if (pgid < 0) @@ -1107,16 +1114,16 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) if (!thread_group_leader(p)) goto out; - if (p->parent == current || p->real_parent == current) { + if (p->real_parent == group_leader) { err = -EPERM; - if (p->signal->session != current->signal->session) + if (p->signal->session != group_leader->signal->session) goto out; err = -EACCES; if (p->did_exec) goto out; } else { err = -ESRCH; - if (p != current) + if (p != group_leader) goto out; } @@ -1128,7 +1135,7 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) struct task_struct *p; do_each_task_pid(pgid, PIDTYPE_PGID, p) { - if (p->signal->session == current->signal->session) + if (p->signal->session == group_leader->signal->session) goto ok_pgid; } while_each_task_pid(pgid, PIDTYPE_PGID, p); goto out; @@ -1208,24 +1215,22 @@ asmlinkage long sys_getsid(pid_t pid) asmlinkage long sys_setsid(void) { + struct task_struct *group_leader = current->group_leader; struct pid *pid; int err = -EPERM; - if (!thread_group_leader(current)) - return -EINVAL; - down(&tty_sem); write_lock_irq(&tasklist_lock); - pid = find_pid(PIDTYPE_PGID, current->pid); + pid = find_pid(PIDTYPE_PGID, group_leader->pid); if (pid) goto out; - current->signal->leader = 1; - __set_special_pids(current->pid, current->pid); - current->signal->tty = NULL; - current->signal->tty_old_pgrp = 0; - err = process_group(current); + group_leader->signal->leader = 1; + __set_special_pids(group_leader->pid, group_leader->pid); + group_leader->signal->tty = NULL; + group_leader->signal->tty_old_pgrp = 0; + err = process_group(group_leader); out: write_unlock_irq(&tasklist_lock); up(&tty_sem); @@ -1687,7 +1692,10 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r) if (unlikely(!p->signal)) return; + utime = stime = cputime_zero; + switch (who) { + case RUSAGE_BOTH: case RUSAGE_CHILDREN: spin_lock_irqsave(&p->sighand->siglock, flags); utime = p->signal->cutime; @@ -1697,22 +1705,11 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r) r->ru_minflt = p->signal->cmin_flt; r->ru_majflt = p->signal->cmaj_flt; spin_unlock_irqrestore(&p->sighand->siglock, flags); - cputime_to_timeval(utime, &r->ru_utime); - cputime_to_timeval(stime, &r->ru_stime); - break; + + if (who == RUSAGE_CHILDREN) + break; + case RUSAGE_SELF: - spin_lock_irqsave(&p->sighand->siglock, flags); - utime = stime = cputime_zero; - goto sum_group; - case RUSAGE_BOTH: - spin_lock_irqsave(&p->sighand->siglock, flags); - utime = p->signal->cutime; - stime = p->signal->cstime; - r->ru_nvcsw = p->signal->cnvcsw; - r->ru_nivcsw = p->signal->cnivcsw; - r->ru_minflt = p->signal->cmin_flt; - r->ru_majflt = p->signal->cmaj_flt; - sum_group: utime = cputime_add(utime, p->signal->utime); stime = cputime_add(stime, p->signal->stime); r->ru_nvcsw += p->signal->nvcsw; @@ -1729,13 +1726,14 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r) r->ru_majflt += t->maj_flt; t = next_thread(t); } while (t != p); - spin_unlock_irqrestore(&p->sighand->siglock, flags); - cputime_to_timeval(utime, &r->ru_utime); - cputime_to_timeval(stime, &r->ru_stime); break; + default: BUG(); } + + cputime_to_timeval(utime, &r->ru_utime); + cputime_to_timeval(stime, &r->ru_stime); } int getrusage(struct task_struct *p, int who, struct rusage __user *ru) diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 1ab2370e2ef..bd3b9bfcfce 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -82,6 +82,28 @@ cond_syscall(compat_sys_socketcall); cond_syscall(sys_inotify_init); cond_syscall(sys_inotify_add_watch); cond_syscall(sys_inotify_rm_watch); +cond_syscall(sys_migrate_pages); +cond_syscall(sys_chown16); +cond_syscall(sys_fchown16); +cond_syscall(sys_getegid16); +cond_syscall(sys_geteuid16); +cond_syscall(sys_getgid16); +cond_syscall(sys_getgroups16); +cond_syscall(sys_getresgid16); +cond_syscall(sys_getresuid16); +cond_syscall(sys_getuid16); +cond_syscall(sys_lchown16); +cond_syscall(sys_setfsgid16); +cond_syscall(sys_setfsuid16); +cond_syscall(sys_setgid16); +cond_syscall(sys_setgroups16); +cond_syscall(sys_setregid16); +cond_syscall(sys_setresgid16); +cond_syscall(sys_setresuid16); +cond_syscall(sys_setreuid16); +cond_syscall(sys_setuid16); +cond_syscall(sys_vm86old); +cond_syscall(sys_vm86); /* arch-specific weak syscall entries */ cond_syscall(sys_pciconfig_read); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index a85047bb573..03b0598f236 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -68,6 +68,8 @@ extern int min_free_kbytes; extern int printk_ratelimit_jiffies; extern int printk_ratelimit_burst; extern int pid_max_min, pid_max_max; +extern int sysctl_drop_caches; +extern int percpu_pagelist_fraction; #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) int unknown_nmi_panic; @@ -78,6 +80,7 @@ extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *, /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */ static int maxolduid = 65535; static int minolduid; +static int min_percpu_pagelist_fract = 8; static int ngroups_max = NGROUPS_MAX; @@ -775,6 +778,15 @@ static ctl_table vm_table[] = { .strategy = &sysctl_intvec, }, { + .ctl_name = VM_DROP_PAGECACHE, + .procname = "drop_caches", + .data = &sysctl_drop_caches, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = drop_caches_sysctl_handler, + .strategy = &sysctl_intvec, + }, + { .ctl_name = VM_MIN_FREE_KBYTES, .procname = "min_free_kbytes", .data = &min_free_kbytes, @@ -784,6 +796,16 @@ static ctl_table vm_table[] = { .strategy = &sysctl_intvec, .extra1 = &zero, }, + { + .ctl_name = VM_PERCPU_PAGELIST_FRACTION, + .procname = "percpu_pagelist_fraction", + .data = &percpu_pagelist_fraction, + .maxlen = sizeof(percpu_pagelist_fraction), + .mode = 0644, + .proc_handler = &percpu_pagelist_fraction_sysctl_handler, + .strategy = &sysctl_intvec, + .extra1 = &min_percpu_pagelist_fract, + }, #ifdef CONFIG_MMU { .ctl_name = VM_MAX_MAP_COUNT, diff --git a/kernel/timer.c b/kernel/timer.c index fd74268d866..074b4bd5cfd 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -33,6 +33,7 @@ #include <linux/posix-timers.h> #include <linux/cpu.h> #include <linux/syscalls.h> +#include <linux/delay.h> #include <asm/uaccess.h> #include <asm/unistd.h> diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 2bd5aee1c73..82c4fa70595 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -29,7 +29,8 @@ #include <linux/kthread.h> /* - * The per-CPU workqueue (if single thread, we always use cpu 0's). + * The per-CPU workqueue (if single thread, we always use the first + * possible cpu). * * The sequence counters are for flush_scheduled_work(). It wants to wait * until until all currently-scheduled works are completed, but it doesn't @@ -69,6 +70,8 @@ struct workqueue_struct { static DEFINE_SPINLOCK(workqueue_lock); static LIST_HEAD(workqueues); +static int singlethread_cpu; + /* If it's single threaded, it isn't in the list of workqueues. */ static inline int is_single_threaded(struct workqueue_struct *wq) { @@ -102,7 +105,7 @@ int fastcall queue_work(struct workqueue_struct *wq, struct work_struct *work) if (!test_and_set_bit(0, &work->pending)) { if (unlikely(is_single_threaded(wq))) - cpu = any_online_cpu(cpu_online_map); + cpu = singlethread_cpu; BUG_ON(!list_empty(&work->entry)); __queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work); ret = 1; @@ -118,7 +121,7 @@ static void delayed_work_timer_fn(unsigned long __data) int cpu = smp_processor_id(); if (unlikely(is_single_threaded(wq))) - cpu = any_online_cpu(cpu_online_map); + cpu = singlethread_cpu; __queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work); } @@ -267,7 +270,7 @@ void fastcall flush_workqueue(struct workqueue_struct *wq) if (is_single_threaded(wq)) { /* Always use first cpu's area. */ - flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, any_online_cpu(cpu_online_map))); + flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, singlethread_cpu)); } else { int cpu; @@ -315,12 +318,17 @@ struct workqueue_struct *__create_workqueue(const char *name, return NULL; wq->cpu_wq = alloc_percpu(struct cpu_workqueue_struct); + if (!wq->cpu_wq) { + kfree(wq); + return NULL; + } + wq->name = name; /* We don't need the distraction of CPUs appearing and vanishing. */ lock_cpu_hotplug(); if (singlethread) { INIT_LIST_HEAD(&wq->list); - p = create_workqueue_thread(wq, any_online_cpu(cpu_online_map)); + p = create_workqueue_thread(wq, singlethread_cpu); if (!p) destroy = 1; else @@ -374,7 +382,7 @@ void destroy_workqueue(struct workqueue_struct *wq) /* We don't need the distraction of CPUs appearing and vanishing. */ lock_cpu_hotplug(); if (is_single_threaded(wq)) - cleanup_workqueue_thread(wq, any_online_cpu(cpu_online_map)); + cleanup_workqueue_thread(wq, singlethread_cpu); else { for_each_online_cpu(cpu) cleanup_workqueue_thread(wq, cpu); @@ -419,6 +427,25 @@ int schedule_delayed_work_on(int cpu, return ret; } +int schedule_on_each_cpu(void (*func) (void *info), void *info) +{ + int cpu; + struct work_struct *work; + + work = kmalloc(NR_CPUS * sizeof(struct work_struct), GFP_KERNEL); + + if (!work) + return -ENOMEM; + for_each_online_cpu(cpu) { + INIT_WORK(work + cpu, func, info); + __queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu), + work + cpu); + } + flush_workqueue(keventd_wq); + kfree(work); + return 0; +} + void flush_scheduled_work(void) { flush_workqueue(keventd_wq); @@ -543,6 +570,7 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, void init_workqueues(void) { + singlethread_cpu = first_cpu(cpu_possible_map); hotcpu_notifier(workqueue_cpu_callback, 0); keventd_wq = create_workqueue("events"); BUG_ON(!keventd_wq); |