From fc0abb1451c64c79ac80665d5ba74450ce274e4d Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 18 Jan 2006 17:42:33 -0800 Subject: [PATCH] [PATCH] sem2mutex: mm/slab.c Convert mm/swapfile.c's swapon_sem to swapon_mutex. Signed-off-by: Ingo Molnar Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slab.c | 46 +++++++++++++++++++++++----------------------- mm/swapfile.c | 17 +++++++++-------- 2 files changed, 32 insertions(+), 31 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index 9374293a301..bd0317f1e06 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -68,7 +68,7 @@ * Further notes from the original documentation: * * 11 April '97. Started multi-threading - markhe - * The global cache-chain is protected by the semaphore 'cache_chain_sem'. + * The global cache-chain is protected by the mutex 'cache_chain_mutex'. * The sem is only needed when accessing/extending the cache-chain, which * can never happen inside an interrupt (kmem_cache_create(), * kmem_cache_shrink() and kmem_cache_reap()). @@ -103,6 +103,7 @@ #include #include #include +#include #include #include @@ -631,7 +632,7 @@ static kmem_cache_t cache_cache = { }; /* Guard access to the cache-chain. */ -static struct semaphore cache_chain_sem; +static DEFINE_MUTEX(cache_chain_mutex); static struct list_head cache_chain; /* @@ -857,7 +858,7 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, switch (action) { case CPU_UP_PREPARE: - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); /* we need to do this right in the beginning since * alloc_arraycache's are going to use this list. * kmalloc_node allows us to add the slab to the right @@ -912,7 +913,7 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, l3->shared = nc; } } - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); break; case CPU_ONLINE: start_cpu_timer(cpu); @@ -921,7 +922,7 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, case CPU_DEAD: /* fall thru */ case CPU_UP_CANCELED: - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); list_for_each_entry(cachep, &cache_chain, next) { struct array_cache *nc; @@ -973,13 +974,13 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, spin_unlock_irq(&cachep->spinlock); kfree(nc); } - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); break; #endif } return NOTIFY_OK; bad: - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); return NOTIFY_BAD; } @@ -1047,7 +1048,6 @@ void __init kmem_cache_init(void) */ /* 1) create the cache_cache */ - init_MUTEX(&cache_chain_sem); INIT_LIST_HEAD(&cache_chain); list_add(&cache_cache.next, &cache_chain); cache_cache.colour_off = cache_line_size(); @@ -1168,10 +1168,10 @@ void __init kmem_cache_init(void) /* 6) resize the head arrays to their final sizes */ { kmem_cache_t *cachep; - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); list_for_each_entry(cachep, &cache_chain, next) enable_cpucache(cachep); - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); } /* Done! */ @@ -1590,7 +1590,7 @@ kmem_cache_create (const char *name, size_t size, size_t align, BUG(); } - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); list_for_each(p, &cache_chain) { kmem_cache_t *pc = list_entry(p, kmem_cache_t, next); @@ -1856,7 +1856,7 @@ kmem_cache_create (const char *name, size_t size, size_t align, if (!cachep && (flags & SLAB_PANIC)) panic("kmem_cache_create(): failed to create slab `%s'\n", name); - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); return cachep; } EXPORT_SYMBOL(kmem_cache_create); @@ -2044,18 +2044,18 @@ int kmem_cache_destroy(kmem_cache_t *cachep) lock_cpu_hotplug(); /* Find the cache in the chain of caches. */ - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); /* * the chain is never empty, cache_cache is never destroyed */ list_del(&cachep->next); - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); if (__cache_shrink(cachep)) { slab_error(cachep, "Can't free all objects"); - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); list_add(&cachep->next, &cache_chain); - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); unlock_cpu_hotplug(); return 1; } @@ -3314,7 +3314,7 @@ static void drain_array_locked(kmem_cache_t *cachep, struct array_cache *ac, * - clear the per-cpu caches for this CPU. * - return freeable pages to the main free memory pool. * - * If we cannot acquire the cache chain semaphore then just give up - we'll + * If we cannot acquire the cache chain mutex then just give up - we'll * try again on the next iteration. */ static void cache_reap(void *unused) @@ -3322,7 +3322,7 @@ static void cache_reap(void *unused) struct list_head *walk; struct kmem_list3 *l3; - if (down_trylock(&cache_chain_sem)) { + if (!mutex_trylock(&cache_chain_mutex)) { /* Give up. Setup the next iteration. */ schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC); @@ -3393,7 +3393,7 @@ static void cache_reap(void *unused) cond_resched(); } check_irq_on(); - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); drain_remote_pages(); /* Setup the next iteration */ schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC); @@ -3429,7 +3429,7 @@ static void *s_start(struct seq_file *m, loff_t *pos) loff_t n = *pos; struct list_head *p; - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); if (!n) print_slabinfo_header(m); p = cache_chain.next; @@ -3451,7 +3451,7 @@ static void *s_next(struct seq_file *m, void *p, loff_t *pos) static void s_stop(struct seq_file *m, void *p) { - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); } static int s_show(struct seq_file *m, void *p) @@ -3603,7 +3603,7 @@ ssize_t slabinfo_write(struct file *file, const char __user * buffer, return -EINVAL; /* Find the cache in the chain of caches. */ - down(&cache_chain_sem); + mutex_lock(&cache_chain_mutex); res = -EINVAL; list_for_each(p, &cache_chain) { kmem_cache_t *cachep = list_entry(p, kmem_cache_t, next); @@ -3620,7 +3620,7 @@ ssize_t slabinfo_write(struct file *file, const char __user * buffer, break; } } - up(&cache_chain_sem); + mutex_unlock(&cache_chain_mutex); if (res >= 0) res = count; return res; diff --git a/mm/swapfile.c b/mm/swapfile.c index 957fef43fa6..f1e69c30d20 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -46,12 +47,12 @@ struct swap_list_t swap_list = {-1, -1}; struct swap_info_struct swap_info[MAX_SWAPFILES]; -static DECLARE_MUTEX(swapon_sem); +static DEFINE_MUTEX(swapon_mutex); /* * We need this because the bdev->unplug_fn can sleep and we cannot * hold swap_lock while calling the unplug_fn. And swap_lock - * cannot be turned into a semaphore. + * cannot be turned into a mutex. */ static DECLARE_RWSEM(swap_unplug_sem); @@ -1161,7 +1162,7 @@ asmlinkage long sys_swapoff(const char __user * specialfile) up_write(&swap_unplug_sem); destroy_swap_extents(p); - down(&swapon_sem); + mutex_lock(&swapon_mutex); spin_lock(&swap_lock); drain_mmlist(); @@ -1180,7 +1181,7 @@ asmlinkage long sys_swapoff(const char __user * specialfile) p->swap_map = NULL; p->flags = 0; spin_unlock(&swap_lock); - up(&swapon_sem); + mutex_unlock(&swapon_mutex); vfree(swap_map); inode = mapping->host; if (S_ISBLK(inode->i_mode)) { @@ -1209,7 +1210,7 @@ static void *swap_start(struct seq_file *swap, loff_t *pos) int i; loff_t l = *pos; - down(&swapon_sem); + mutex_lock(&swapon_mutex); for (i = 0; i < nr_swapfiles; i++, ptr++) { if (!(ptr->flags & SWP_USED) || !ptr->swap_map) @@ -1238,7 +1239,7 @@ static void *swap_next(struct seq_file *swap, void *v, loff_t *pos) static void swap_stop(struct seq_file *swap, void *v) { - up(&swapon_sem); + mutex_unlock(&swapon_mutex); } static int swap_show(struct seq_file *swap, void *v) @@ -1540,7 +1541,7 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) goto bad_swap; } - down(&swapon_sem); + mutex_lock(&swapon_mutex); spin_lock(&swap_lock); p->flags = SWP_ACTIVE; nr_swap_pages += nr_good_pages; @@ -1566,7 +1567,7 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) swap_info[prev].next = p - swap_info; } spin_unlock(&swap_lock); - up(&swapon_sem); + mutex_unlock(&swapon_mutex); error = 0; goto out; bad_swap: -- 2.41.1