xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

frv: split ret_from_fork, simplify kernel_thread() a lot

Browse Source 
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
2012-09-18 22:18:51 -04:00
parent d878d6dace
commit 02ce496f15
5 changed files with 30 additions and 98 deletions
Download Patch File Download Diff File Expand all files Collapse all files

40
arch/frv/kernel/process.c
View File

@@ -37,6 +37,7 @@
#include "local.h"
asmlinkage void ret_from_fork(void);
asmlinkage void ret_from_kernel_thread(void);
#include <asm/pgalloc.h>
@@ -172,29 +173,21 @@ int copy_thread(unsigned long clone_flags,
unsigned long usp, unsigned long topstk,
struct task_struct *p, struct pt_regs *regs)
{
struct pt_regs *childregs0, *childregs, *regs0;
struct pt_regs *childregs;
regs0 = __kernel_frame0_ptr;
childregs0 = (struct pt_regs *)
childregs = (struct pt_regs *)
(task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_SIZE);
childregs = childregs0;
/* set up the userspace frame (the only place that the USP is stored) */
*childregs0 = *regs0;
*childregs = *regs;
childregs0->gr8 = 0;
childregs0->sp = usp;
childregs0->next_frame = NULL;
childregs->sp = usp;
childregs->next_frame = NULL;
/* set up the return kernel frame if called from kernel_thread() */
if (regs != regs0) {
childregs--;
*childregs = *regs;
childregs->sp = (unsigned long) childregs0;
childregs->next_frame = childregs0;
childregs->gr15 = (unsigned long) task_thread_info(p);
childregs->gr29 = (unsigned long) p;
}
if (unlikely(!user_mode(regs)))
p->thread.pc = (unsigned long) ret_from_kernel_thread;
else
p->thread.pc = (unsigned long) ret_from_fork;
p->set_child_tid = p->clear_child_tid = NULL;
@@ -203,8 +196,7 @@ int copy_thread(unsigned long clone_flags,
p->thread.sp = (unsigned long) childregs;
p->thread.fp = 0;
p->thread.lr = 0;
p->thread.pc = (unsigned long) ret_from_fork;
p->thread.frame0 = childregs0;
p->thread.frame0 = childregs;
/* the new TLS pointer is passed in as arg #5 to sys_clone() */
if (clone_flags & CLONE_SETTLS)
@@ -347,3 +339,13 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
sizeof(current->thread.user->f));
return 1;
}
int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
struct pt_regs regs = {
.gr8 = (unsigned long)arg;
.gr9 = (unsigned long)fn;
.psr = PSR_S;
};
return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
}