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>
This commit is contained in:
Suresh Siddha 2012-05-16 15:03:51 -07:00 committed by H. Peter Anvin
parent 36be50515f
commit 55ccf3fe3f
39 changed files with 36 additions and 140 deletions

View file

@ -49,9 +49,6 @@ extern void start_thread(struct pt_regs *, unsigned long, unsigned long);
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
/* Create a kernel thread without removing it from tasklists. */
extern long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);

View file

@ -77,9 +77,6 @@ struct task_struct;
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
unsigned long get_wchan(struct task_struct *p);
#if __LINUX_ARM_ARCH__ == 6 || defined(CONFIG_ARM_ERRATA_754327)

View file

@ -145,9 +145,6 @@ extern void release_thread(struct task_struct *);
/* Create a kernel thread without removing it from tasklists */
extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while(0)
/* Return saved PC of a blocked thread */
#define thread_saved_pc(tsk) ((tsk)->thread.cpu_context.pc)

View file

@ -75,8 +75,6 @@ static inline void release_thread(struct task_struct *dead_task)
{
}
#define prepare_to_copy(tsk) do { } while (0)
extern int kernel_thread(int (*fn) (void *), void *arg, unsigned long flags);
/*

View file

@ -92,9 +92,6 @@ static inline void release_thread(struct task_struct *dead_task)
{
}
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
#define copy_segments(tsk, mm) do { } while (0)

View file

@ -50,10 +50,6 @@ struct task_struct;
#define task_pt_regs(task) user_regs(task_thread_info(task))
#define current_regs() task_pt_regs(current)
static inline void prepare_to_copy(struct task_struct *tsk)
{
}
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
unsigned long get_wchan(struct task_struct *p);

View file

@ -103,8 +103,6 @@ do { \
__frame->sp = (_usp); \
} while(0)
extern void prepare_to_copy(struct task_struct *tsk);
/* Free all resources held by a thread. */
static inline void release_thread(struct task_struct *dead_task)
{

View file

@ -180,17 +180,6 @@ asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
} /* end sys_clone() */
/*****************************************************************************/
/*
* This gets called before we allocate a new thread and copy
* the current task into it.
*/
void prepare_to_copy(struct task_struct *tsk)
{
//unlazy_fpu(tsk);
} /* end prepare_to_copy() */
/*****************************************************************************/
/*
* set up the kernel stack and exception frames for a new process
*/

View file

@ -109,8 +109,6 @@ static inline void release_thread(struct task_struct *dead_task)
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
#define prepare_to_copy(tsk) do { } while (0)
/*
* Free current thread data structures etc..
*/

View file

@ -58,13 +58,6 @@ struct thread_struct {
#define cpu_relax() __vmyield()
/*
* "Unlazying all lazy status" occurs here.
*/
static inline void prepare_to_copy(struct task_struct *tsk)
{
}
/*
* Decides where the kernel will search for a free chunk of vm space during
* mmaps.

View file

@ -343,9 +343,6 @@ struct task_struct;
*/
#define release_thread(dead_task)
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
/*
* This is the mechanism for creating a new kernel thread.
*

View file

@ -118,8 +118,6 @@ struct mm_struct;
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
#define prepare_to_copy(tsk) do { } while (0)
/*
* create a kernel thread without removing it from tasklists
*/

View file

@ -153,9 +153,6 @@ static inline void release_thread(struct task_struct *dead_task)
{
}
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
/*

View file

@ -23,7 +23,6 @@ extern const struct seq_operations cpuinfo_op;
# define cpu_relax() barrier()
# define cpu_sleep() do {} while (0)
# define prepare_to_copy(tsk) do {} while (0)
#define task_pt_regs(tsk) \
(((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)

View file

@ -310,9 +310,6 @@ struct task_struct;
/* Free all resources held by a thread. */
#define release_thread(thread) do { } while(0)
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
extern unsigned long thread_saved_pc(struct task_struct *tsk);

View file

@ -139,9 +139,6 @@ static inline void start_thread(struct pt_regs *regs,
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
/* Prepare to copy thread state - unlazy all lazy status */
extern void prepare_to_copy(struct task_struct *tsk);
/*
* create a kernel thread without removing it from tasklists
*/

View file

@ -208,12 +208,14 @@ void copy_segments(struct task_struct *p, struct mm_struct *new_mm)
}
/*
* this gets called before we allocate a new thread and copy the current task
* into it so that we can store lazy state into memory
* this gets called so that we can store lazy state into memory and copy the
* current task into the new thread.
*/
void prepare_to_copy(struct task_struct *tsk)
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
unlazy_fpu(tsk);
unlazy_fpu(src);
*dst = *src;
return 0;
}
/*

View file

@ -72,10 +72,6 @@ struct thread_struct {
#define task_pt_regs(task) user_regs(task_thread_info(task))
#define current_regs() user_regs(current_thread_info())
extern inline void prepare_to_copy(struct task_struct *tsk)
{
}
#define INIT_SP (sizeof(init_stack) + (unsigned long) &init_stack)
#define INIT_THREAD { }

View file

@ -328,9 +328,6 @@ struct mm_struct;
extern void release_thread(struct task_struct *);
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
extern void map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm);
extern unsigned long get_wchan(struct task_struct *p);

View file

@ -74,9 +74,6 @@ struct task_struct;
void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp);
void release_thread(struct task_struct *);
/* Prepare to copy thread state - unlazy all lazy status */
extern void prepare_to_copy(struct task_struct *tsk);
/* Create a new kernel thread. */
extern long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);

View file

@ -711,18 +711,21 @@ release_thread(struct task_struct *t)
}
/*
* This gets called before we allocate a new thread and copy
* the current task into it.
* this gets called so that we can store coprocessor state into memory and
* copy the current task into the new thread.
*/
void prepare_to_copy(struct task_struct *tsk)
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
flush_fp_to_thread(current);
flush_altivec_to_thread(current);
flush_vsx_to_thread(current);
flush_spe_to_thread(current);
flush_fp_to_thread(src);
flush_altivec_to_thread(src);
flush_vsx_to_thread(src);
flush_spe_to_thread(src);
#ifdef CONFIG_HAVE_HW_BREAKPOINT
flush_ptrace_hw_breakpoint(tsk);
flush_ptrace_hw_breakpoint(src);
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
*dst = *src;
return 0;
}
/*

View file

@ -141,9 +141,6 @@ struct seq_file;
extern void release_thread(struct task_struct *);
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
/*
* Return saved PC of a blocked thread.
*/

View file

@ -26,7 +26,6 @@ extern unsigned long get_wchan(struct task_struct *p);
#define cpu_relax() barrier()
#define release_thread(thread) do {} while (0)
#define prepare_to_copy(tsk) do {} while (0)
/*
* User space process size: 2GB. This is hardcoded into a few places,

View file

@ -126,9 +126,6 @@ extern void start_thread(struct pt_regs *regs, unsigned long new_pc, unsigned lo
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
/* Prepare to copy thread state - unlazy all lazy status */
void prepare_to_copy(struct task_struct *tsk);
/*
* create a kernel thread without removing it from tasklists
*/

View file

@ -172,7 +172,6 @@ extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
#define copy_segments(p, mm) do { } while (0)
#define release_segments(mm) do { } while (0)
#define forget_segments() do { } while (0)
#define prepare_to_copy(tsk) do { } while (0)
/*
* FPU lazy state save handling.
*/

View file

@ -6,8 +6,15 @@
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) {

View file

@ -155,15 +155,6 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
}
EXPORT_SYMBOL(dump_fpu);
/*
* This gets called before we allocate a new thread and copy
* the current task into it.
*/
void prepare_to_copy(struct task_struct *tsk)
{
unlazy_fpu(tsk, task_pt_regs(tsk));
}
asmlinkage void ret_from_fork(void);
int copy_thread(unsigned long clone_flags, unsigned long usp,

View file

@ -109,9 +109,6 @@ static inline void start_thread(struct pt_regs * regs, unsigned long pc,
#define release_thread(tsk) do { } while(0)
extern pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
extern unsigned long get_wchan(struct task_struct *);
#define task_pt_regs(tsk) ((tsk)->thread.kregs)

View file

@ -186,9 +186,6 @@ do { \
/* Free all resources held by a thread. */
#define release_thread(tsk) do { } while (0)
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
extern pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
extern unsigned long get_wchan(struct task_struct *task);

View file

@ -210,9 +210,6 @@ static inline void release_thread(struct task_struct *dead_task)
/* Nothing for now */
}
/* Prepare to copy thread state - unlazy all lazy status. */
#define prepare_to_copy(tsk) do { } while (0)
extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
extern int do_work_pending(struct pt_regs *regs, u32 flags);

View file

@ -76,11 +76,6 @@ static inline void release_thread(struct task_struct *task)
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
static inline void prepare_to_copy(struct task_struct *tsk)
{
}
extern unsigned long thread_saved_pc(struct task_struct *t);
static inline void mm_copy_segments(struct mm_struct *from_mm,

View file

@ -68,9 +68,6 @@ struct task_struct;
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
unsigned long get_wchan(struct task_struct *p);
#define cpu_relax() barrier()

View file

@ -579,9 +579,6 @@ extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
/* Prepare to copy thread state - unlazy all lazy state */
extern void prepare_to_copy(struct task_struct *tsk);
unsigned long get_wchan(struct task_struct *p);
/*

View file

@ -47,10 +47,16 @@ EXPORT_SYMBOL_GPL(idle_notifier_unregister);
struct kmem_cache *task_xstate_cachep;
EXPORT_SYMBOL_GPL(task_xstate_cachep);
/*
* 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)
{
int ret;
unlazy_fpu(src);
*dst = *src;
if (fpu_allocated(&src->thread.fpu)) {
memset(&dst->thread.fpu, 0, sizeof(dst->thread.fpu));

View file

@ -126,15 +126,6 @@ void release_thread(struct task_struct *dead_task)
release_vm86_irqs(dead_task);
}
/*
* This gets called before we allocate a new thread and copy
* the current task into it.
*/
void prepare_to_copy(struct task_struct *tsk)
{
unlazy_fpu(tsk);
}
int copy_thread(unsigned long clone_flags, unsigned long sp,
unsigned long unused,
struct task_struct *p, struct pt_regs *regs)

View file

@ -145,15 +145,6 @@ static inline u32 read_32bit_tls(struct task_struct *t, int tls)
return get_desc_base(&t->thread.tls_array[tls]);
}
/*
* This gets called before we allocate a new thread and copy
* the current task into it.
*/
void prepare_to_copy(struct task_struct *tsk)
{
unlazy_fpu(tsk);
}
int copy_thread(unsigned long clone_flags, unsigned long sp,
unsigned long unused,
struct task_struct *p, struct pt_regs *regs)

View file

@ -168,9 +168,6 @@ struct mm_struct;
/* Free all resources held by a thread. */
#define release_thread(thread) do { } while(0)
/* Prepare to copy thread state - unlazy all lazy status */
extern void prepare_to_copy(struct task_struct*);
/* Create a kernel thread without removing it from tasklists */
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);

View file

@ -140,13 +140,16 @@ void flush_thread(void)
}
/*
* This is called before the thread is copied.
* this gets called so that we can store coprocessor state into memory and
* copy the current task into the new thread.
*/
void prepare_to_copy(struct task_struct *tsk)
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
#if XTENSA_HAVE_COPROCESSORS
coprocessor_flush_all(task_thread_info(tsk));
coprocessor_flush_all(task_thread_info(src));
#endif
*dst = *src;
return 0;
}
/*

View file

@ -261,8 +261,6 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
int node = tsk_fork_get_node(orig);
int err;
prepare_to_copy(orig);
tsk = alloc_task_struct_node(node);
if (!tsk)
return NULL;