parisc: switch to generic kernel_thread()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2012-10-03 23:28:08 -04:00
parent ddffeb8c4d
commit a44e060fc5
3 changed files with 18 additions and 89 deletions

View file

@ -22,6 +22,7 @@ config PARISC
select GENERIC_STRNCPY_FROM_USER
select HAVE_MOD_ARCH_SPECIFIC
select MODULES_USE_ELF_RELA
select GENERIC_KERNEL_THREAD
help
The PA-RISC microprocessor is designed by Hewlett-Packard and used

View file

@ -707,60 +707,10 @@ ENTRY(end_fault_vector)
.import handle_interruption,code
.import do_cpu_irq_mask,code
/*
* r26 = function to be called
* r25 = argument to pass in
* r24 = flags for do_fork()
*
* Kernel threads don't ever return, so they don't need
* a true register context. We just save away the arguments
* for copy_thread/ret_ to properly set up the child.
*/
#define CLONE_VM 0x100 /* Must agree with <linux/sched.h> */
#define CLONE_UNTRACED 0x00800000
.import do_fork
ENTRY(__kernel_thread)
STREG %r2, -RP_OFFSET(%r30)
copy %r30, %r1
ldo PT_SZ_ALGN(%r30),%r30
#ifdef CONFIG_64BIT
/* Yo, function pointers in wide mode are little structs... -PB */
ldd 24(%r26), %r2
STREG %r2, PT_GR27(%r1) /* Store childs %dp */
ldd 16(%r26), %r26
STREG %r22, PT_GR22(%r1) /* save r22 (arg5) */
copy %r0, %r22 /* user_tid */
#endif
STREG %r26, PT_GR26(%r1) /* Store function & argument for child */
STREG %r25, PT_GR25(%r1)
ldil L%CLONE_UNTRACED, %r26
ldo CLONE_VM(%r26), %r26 /* Force CLONE_VM since only init_mm */
or %r26, %r24, %r26 /* will have kernel mappings. */
ldi 1, %r25 /* stack_start, signals kernel thread */
stw %r0, -52(%r30) /* user_tid */
#ifdef CONFIG_64BIT
ldo -16(%r30),%r29 /* Reference param save area */
#endif
BL do_fork, %r2
copy %r1, %r24 /* pt_regs */
/* Parent Returns here */
LDREG -PT_SZ_ALGN-RP_OFFSET(%r30), %r2
ldo -PT_SZ_ALGN(%r30), %r30
bv %r0(%r2)
nop
ENDPROC(__kernel_thread)
/*
* Child Returns here
*
* copy_thread moved args from temp save area set up above
* into task save area.
* copy_thread moved args into task save area.
*/
ENTRY(ret_from_kernel_thread)
@ -773,7 +723,6 @@ ENTRY(ret_from_kernel_thread)
LDREG TASK_PT_GR25(%r1), %r26
#ifdef CONFIG_64BIT
LDREG TASK_PT_GR27(%r1), %r27
LDREG TASK_PT_GR22(%r1), %r22
#endif
LDREG TASK_PT_GR26(%r1), %r1
ble 0(%sr7, %r1)

View file

@ -164,23 +164,6 @@ void machine_power_off(void)
void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);
/*
* Create a kernel thread
*/
extern pid_t __kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
/*
* FIXME: Once we are sure we don't need any debug here,
* kernel_thread can become a #define.
*/
return __kernel_thread(fn, arg, flags);
}
EXPORT_SYMBOL(kernel_thread);
/*
* Free current thread data structures etc..
*/
@ -256,8 +239,8 @@ sys_vfork(struct pt_regs *regs)
int
copy_thread(unsigned long clone_flags, unsigned long usp,
unsigned long unused, /* in ia64 this is "user_stack_size" */
struct task_struct * p, struct pt_regs * pregs)
unsigned long arg,
struct task_struct *p, struct pt_regs *pregs)
{
struct pt_regs * cregs = &(p->thread.regs);
void *stack = task_stack_page(p);
@ -271,21 +254,8 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
extern void * const hpux_child_return;
#endif
*cregs = *pregs;
/* Set the return value for the child. Note that this is not
actually restored by the syscall exit path, but we put it
here for consistency in case of signals. */
cregs->gr[28] = 0; /* child */
/*
* We need to differentiate between a user fork and a
* kernel fork. We can't use user_mode, because the
* the syscall path doesn't save iaoq. Right now
* We rely on the fact that kernel_thread passes
* in zero for usp.
*/
if (usp == 1) {
if (unlikely((p->flags & PF_KTHREAD) && usp != 0)) {
memset(cregs, 0, sizeof(struct pt_regs));
/* kernel thread */
cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
/* Must exit via ret_from_kernel_thread in order
@ -297,10 +267,12 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
* ret_from_kernel_thread.
*/
#ifdef CONFIG_64BIT
cregs->gr[27] = pregs->gr[27];
cregs->gr[27] = ((unsigned long *)usp)[3];
cregs->gr[26] = ((unsigned long *)usp)[2];
#else
cregs->gr[26] = usp;
#endif
cregs->gr[26] = pregs->gr[26];
cregs->gr[25] = pregs->gr[25];
cregs->gr[25] = arg;
} else {
/* user thread */
/*
@ -308,6 +280,13 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
* for setting gr[21].
*/
*cregs = *pregs;
/* Set the return value for the child. Note that this is not
actually restored by the syscall exit path, but we put it
here for consistency in case of signals. */
cregs->gr[28] = 0; /* child */
/* Use same stack depth as parent */
cregs->ksp = (unsigned long)stack
+ (pregs->gr[21] & (THREAD_SIZE - 1));