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sparc32: switch to generic kernel_thread()

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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2012-09-27 15:21:21 -04:00
parent 32942bc7a6
commit c78e06430e
4 changed files with 56 additions and 81 deletions
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2
arch/sparc/Kconfig
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@ -40,6 +40,7 @@ config SPARC
select GENERIC_STRNCPY_FROM_USER
select GENERIC_STRNLEN_USER
select MODULES_USE_ELF_RELA
select GENERIC_KERNEL_THREAD
config SPARC32
def_bool !64BIT
@ -74,7 +75,6 @@ config SPARC64
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select HAVE_C_RECORDMCOUNT
select NO_BOOTMEM
select GENERIC_KERNEL_THREAD
select GENERIC_KERNEL_EXECVE
config ARCH_DEFCONFIG

1
arch/sparc/include/asm/processor_32.h
View File

@ -106,7 +106,6 @@ static inline void start_thread(struct pt_regs * regs, unsigned long pc,
/* Free all resources held by a thread. */
#define release_thread(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 *);

10
arch/sparc/kernel/entry.S
View File

@ -983,6 +983,16 @@ ret_from_fork:
b ret_sys_call
ld [%sp + STACKFRAME_SZ + PT_I0], %o0
.globl ret_from_kernel_thread
ret_from_kernel_thread:
call schedule_tail
ld [%g3 + TI_TASK], %o0
ld [%sp + STACKFRAME_SZ + PT_G1], %l0
call %l0
ld [%sp + STACKFRAME_SZ + PT_G2], %o0
call do_exit /* won't return */
clr %o0
/* Linux native system calls enter here... */
.align 4
.globl linux_sparc_syscall

124
arch/sparc/kernel/process_32.c
View File

@ -316,9 +316,10 @@ asmlinkage int sparc_do_fork(unsigned long clone_flags,
* XXX See comment above sys_vfork in sparc64. todo.
*/
extern void ret_from_fork(void);
extern void ret_from_kernel_thread(void);
int copy_thread(unsigned long clone_flags, unsigned long sp,
unsigned long unused,
unsigned long arg,
struct task_struct *p, struct pt_regs *regs)
{
struct thread_info *ti = task_thread_info(p);
@ -336,16 +337,13 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
}
/*
* p->thread_info new_stack childregs
* ! ! ! {if(PSR_PS) }
* V V (stk.fr.) V (pt_regs) { (stk.fr.) }
* +----- - - - - - ------+===========+============={+==========}+
* p->thread_info new_stack childregs stack bottom
* ! ! ! !
* V V (stk.fr.) V (pt_regs) V
* +----- - - - - - ------+===========+=============+
*/
new_stack = task_stack_page(p) + THREAD_SIZE;
if (regs->psr & PSR_PS)
new_stack -= STACKFRAME_SZ;
new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
/*
@ -356,55 +354,58 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
* Thus, kpsr|=PSR_PIL.
*/
ti->ksp = (unsigned long) new_stack;
p->thread.kregs = childregs;
if (unlikely(p->flags & PF_KTHREAD)) {
extern int nwindows;
unsigned long psr;
memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
p->thread.flags |= SPARC_FLAG_KTHREAD;
p->thread.current_ds = KERNEL_DS;
ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);
childregs->u_regs[UREG_G1] = sp; /* function */
childregs->u_regs[UREG_G2] = arg;
psr = childregs->psr = get_psr();
ti->kpsr = psr | PSR_PIL;
ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows);
return 0;
}
memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
childregs->u_regs[UREG_FP] = sp;
p->thread.flags &= ~SPARC_FLAG_KTHREAD;
p->thread.current_ds = USER_DS;
ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
ti->kwim = current->thread.fork_kwim;
if(regs->psr & PSR_PS) {
extern struct pt_regs fake_swapper_regs;
if (sp != regs->u_regs[UREG_FP]) {
struct sparc_stackf __user *childstack;
struct sparc_stackf __user *parentstack;
p->thread.kregs = &fake_swapper_regs;
new_stack += STACKFRAME_SZ + TRACEREG_SZ;
childregs->u_regs[UREG_FP] = (unsigned long) new_stack;
p->thread.flags |= SPARC_FLAG_KTHREAD;
p->thread.current_ds = KERNEL_DS;
memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ);
childregs->u_regs[UREG_G6] = (unsigned long) ti;
} else {
p->thread.kregs = childregs;
childregs->u_regs[UREG_FP] = sp;
p->thread.flags &= ~SPARC_FLAG_KTHREAD;
p->thread.current_ds = USER_DS;
if (sp != regs->u_regs[UREG_FP]) {
struct sparc_stackf __user *childstack;
struct sparc_stackf __user *parentstack;
/*
* This is a clone() call with supplied user stack.
* Set some valid stack frames to give to the child.
*/
childstack = (struct sparc_stackf __user *)
(sp & ~0xfUL);
parentstack = (struct sparc_stackf __user *)
regs->u_regs[UREG_FP];
/*
* This is a clone() call with supplied user stack.
* Set some valid stack frames to give to the child.
*/
childstack = (struct sparc_stackf __user *)
(sp & ~0xfUL);
parentstack = (struct sparc_stackf __user *)
regs->u_regs[UREG_FP];
#if 0
printk("clone: parent stack:\n");
show_stackframe(parentstack);
printk("clone: parent stack:\n");
show_stackframe(parentstack);
#endif
childstack = clone_stackframe(childstack, parentstack);
if (!childstack)
return -EFAULT;
childstack = clone_stackframe(childstack, parentstack);
if (!childstack)
return -EFAULT;
#if 0
printk("clone: child stack:\n");
show_stackframe(childstack);
printk("clone: child stack:\n");
show_stackframe(childstack);
#endif
childregs->u_regs[UREG_FP] = (unsigned long)childstack;
}
childregs->u_regs[UREG_FP] = (unsigned long)childstack;
}
#ifdef CONFIG_SMP
@ -503,41 +504,6 @@ out:
return error;
}
/*
* This is the mechanism for creating a new kernel thread.
*
* NOTE! Only a kernel-only process(ie the swapper or direct descendants
* who haven't done an "execve()") should use this: it will work within
* a system call from a "real" process, but the process memory space will
* not be freed until both the parent and the child have exited.
*/
pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
long retval;
__asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */
"mov %5, %%g3\n\t" /* and arg. */
"mov %1, %%g1\n\t"
"mov %2, %%o0\n\t" /* Clone flags. */
"mov 0, %%o1\n\t" /* usp arg == 0 */
"t 0x10\n\t" /* Linux/Sparc clone(). */
"cmp %%o1, 0\n\t"
"be 1f\n\t" /* The parent, just return. */
" nop\n\t" /* Delay slot. */
"jmpl %%g2, %%o7\n\t" /* Call the function. */
" mov %%g3, %%o0\n\t" /* Get back the arg in delay. */
"mov %3, %%g1\n\t"
"t 0x10\n\t" /* Linux/Sparc exit(). */
/* Notreached by child. */
"1: mov %%o0, %0\n\t" :
"=r" (retval) :
"i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
"i" (__NR_exit), "r" (fn), "r" (arg) :
"g1", "g2", "g3", "o0", "o1", "memory", "cc");
return retval;
}
EXPORT_SYMBOL(kernel_thread);
unsigned long get_wchan(struct task_struct *task)
{
unsigned long pc, fp, bias = 0;