diff options
| author | Justus Winter <4winter@informatik.uni-hamburg.de> | 2015-07-02 16:20:44 +0200 |
|---|---|---|
| committer | Justus Winter <4winter@informatik.uni-hamburg.de> | 2015-09-14 14:45:06 +0200 |
| commit | 7123adf2541a4a804edccd3a0393717c2f6d658c (patch) | |
| tree | 590c23b543b514fa71e7446b5c0fcabb5b38db93 | |
| parent | daf6353b9fd988e5d35657b1aaf21d5b69ba0c4f (diff) | |
kern: allocate kernel stacks using the slab allocator
* kern/slab.c (kmem_cache_init): Relax alignment restriction.
* kern/thread.c (stack_cache): New variable.
(stack_alloc): Use the slab allocator.
(stack_collect): Adjust accordingly.
(thread_init): Initialize `stack_cache'.
| -rw-r--r-- | kern/slab.c | 1 | ||||
| -rw-r--r-- | kern/thread.c | 29 |
2 files changed, 19 insertions, 11 deletions
diff --git a/kern/slab.c b/kern/slab.c index 1114cfa..5140130 100644 --- a/kern/slab.c +++ b/kern/slab.c @@ -800,7 +800,6 @@ void kmem_cache_init(struct kmem_cache *cache, const char *name, assert(obj_size > 0); assert(ISP2(align)); - assert(align < PAGE_SIZE); buf_size = P2ROUND(obj_size, align); diff --git a/kern/thread.c b/kern/thread.c index b996559..3586e34 100644 --- a/kern/thread.c +++ b/kern/thread.c @@ -165,6 +165,11 @@ boolean_t stack_alloc_try( } /* + * We allocate kernel stacks using the slab allocator. + */ +static struct kmem_cache stack_cache; + +/* * stack_alloc: * * Allocate a kernel stack for a thread. @@ -195,15 +200,10 @@ kern_return_t stack_alloc( (void) splx(s); if (stack == 0) { - kern_return_t kr; - /* - * Kernel stacks should be naturally aligned, - * so that it is easy to find the starting/ending - * addresses of a stack given an address in the middle. - */ - kr = kmem_alloc_aligned(kmem_map, &stack, KERNEL_STACK_SIZE); - if (kr != KERN_SUCCESS) - return kr; + stack = kmem_cache_alloc(&stack_cache); + assert ((stack & (KERNEL_STACK_SIZE-1)) == 0); + if (stack == 0) + return KERN_RESOURCE_SHORTAGE; #if MACH_DEBUG stack_init(stack); @@ -265,7 +265,7 @@ void stack_collect(void) #if MACH_DEBUG stack_finalize(stack); #endif /* MACH_DEBUG */ - kmem_free(kmem_map, stack, KERNEL_STACK_SIZE); + kmem_cache_free(&stack_cache, stack); s = splsched(); stack_lock(); @@ -301,6 +301,15 @@ void thread_init(void) NULL, NULL, NULL, 0); /* + * Kernel stacks should be naturally aligned, so that it + * is easy to find the starting/ending addresses of a + * stack given an address in the middle. + */ + kmem_cache_init(&stack_cache, "stack", + KERNEL_STACK_SIZE, KERNEL_STACK_SIZE, + NULL, NULL, NULL, 0); + + /* * Fill in a template thread for fast initialization. * [Fields that must be (or are typically) reset at * time of creation are so noted.] |