linux/arch/sh/kernel/process.c
Suresh Siddha 55ccf3fe3f fork: move the real prepare_to_copy() users to arch_dup_task_struct()
Historical prepare_to_copy() is mostly a no-op, duplicated for majority of
the architectures and the rest following the x86 model of flushing the extended
register state like fpu there.

Remove it and use the arch_dup_task_struct() instead.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.com
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-16 15:16:26 -07:00

111 lines
2.5 KiB
C

#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/sched.h>
struct kmem_cache *task_xstate_cachep = NULL;
unsigned int xstate_size;
/*
* this gets called so that we can store lazy state into memory and copy the
* current task into the new thread.
*/
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
#ifdef CONFIG_SUPERH32
unlazy_fpu(src, task_pt_regs(src));
#endif
*dst = *src;
if (src->thread.xstate) {
dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
GFP_KERNEL);
if (!dst->thread.xstate)
return -ENOMEM;
memcpy(dst->thread.xstate, src->thread.xstate, xstate_size);
}
return 0;
}
void free_thread_xstate(struct task_struct *tsk)
{
if (tsk->thread.xstate) {
kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
tsk->thread.xstate = NULL;
}
}
#if THREAD_SHIFT < PAGE_SHIFT
static struct kmem_cache *thread_info_cache;
struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node)
{
struct thread_info *ti;
#ifdef CONFIG_DEBUG_STACK_USAGE
gfp_t mask = GFP_KERNEL | __GFP_ZERO;
#else
gfp_t mask = GFP_KERNEL;
#endif
ti = kmem_cache_alloc_node(thread_info_cache, mask, node);
return ti;
}
void free_thread_info(struct thread_info *ti)
{
free_thread_xstate(ti->task);
kmem_cache_free(thread_info_cache, ti);
}
void thread_info_cache_init(void)
{
thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
THREAD_SIZE, SLAB_PANIC, NULL);
}
#else
struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node)
{
#ifdef CONFIG_DEBUG_STACK_USAGE
gfp_t mask = GFP_KERNEL | __GFP_ZERO;
#else
gfp_t mask = GFP_KERNEL;
#endif
struct page *page = alloc_pages_node(node, mask, THREAD_SIZE_ORDER);
return page ? page_address(page) : NULL;
}
void free_thread_info(struct thread_info *ti)
{
free_thread_xstate(ti->task);
free_pages((unsigned long)ti, THREAD_SIZE_ORDER);
}
#endif /* THREAD_SHIFT < PAGE_SHIFT */
void arch_task_cache_init(void)
{
if (!xstate_size)
return;
task_xstate_cachep = kmem_cache_create("task_xstate", xstate_size,
__alignof__(union thread_xstate),
SLAB_PANIC | SLAB_NOTRACK, NULL);
}
#ifdef CONFIG_SH_FPU_EMU
# define HAVE_SOFTFP 1
#else
# define HAVE_SOFTFP 0
#endif
void __cpuinit init_thread_xstate(void)
{
if (boot_cpu_data.flags & CPU_HAS_FPU)
xstate_size = sizeof(struct sh_fpu_hard_struct);
else if (HAVE_SOFTFP)
xstate_size = sizeof(struct sh_fpu_soft_struct);
else
xstate_size = 0;
}