From 61c4628b538608c1a85211ed8438136adfeb9a95 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Mon, 10 Mar 2008 15:28:04 -0700 Subject: x86, fpu: split FPU state from task struct - v5 Split the FPU save area from the task struct. This allows easy migration of FPU context, and it's generally cleaner. It also allows the following two optimizations: 1) only allocate when the application actually uses FPU, so in the first lazy FPU trap. This could save memory for non-fpu using apps. Next patch does this lazy allocation. 2) allocate the right size for the actual cpu rather than 512 bytes always. Patches enabling xsave/xrstor support (coming shortly) will take advantage of this. Signed-off-by: Suresh Siddha Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/process.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 arch/x86/kernel/process.c (limited to 'arch/x86/kernel/process.c') diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c new file mode 100644 index 00000000000..ead24efbcba --- /dev/null +++ b/arch/x86/kernel/process.c @@ -0,0 +1,35 @@ +#include +#include +#include +#include +#include +#include + +static struct kmem_cache *task_xstate_cachep; + +int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) +{ + *dst = *src; + dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep, GFP_KERNEL); + if (!dst->thread.xstate) + return -ENOMEM; + WARN_ON((unsigned long)dst->thread.xstate & 15); + memcpy(dst->thread.xstate, src->thread.xstate, xstate_size); + return 0; +} + +void free_thread_info(struct thread_info *ti) +{ + kmem_cache_free(task_xstate_cachep, ti->task->thread.xstate); + ti->task->thread.xstate = NULL; + + free_pages((unsigned long)(ti), get_order(THREAD_SIZE)); +} + +void arch_task_cache_init(void) +{ + task_xstate_cachep = + kmem_cache_create("task_xstate", xstate_size, + __alignof__(union thread_xstate), + SLAB_PANIC, NULL); +} -- cgit v1.2.3-18-g5258