From c78e06430ea621ce59d20cb899a9a86bdcf4487b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 27 Sep 2012 15:21:21 -0400 Subject: [PATCH] sparc32: switch to generic kernel_thread() Signed-off-by: Al Viro --- arch/sparc/Kconfig | 2 +- arch/sparc/include/asm/processor_32.h | 1 - arch/sparc/kernel/entry.S | 10 +++ arch/sparc/kernel/process_32.c | 124 ++++++++++---------------- 4 files changed, 56 insertions(+), 81 deletions(-) diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index e47eb324d77a..edc4ede8ec3e 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -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 diff --git a/arch/sparc/include/asm/processor_32.h b/arch/sparc/include/asm/processor_32.h index f74ac9ee33a8..c1e01914fd98 100644 --- a/arch/sparc/include/asm/processor_32.h +++ b/arch/sparc/include/asm/processor_32.h @@ -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 *); diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S index dc089702e00a..6114672a1b0e 100644 --- a/arch/sparc/kernel/entry.S +++ b/arch/sparc/kernel/entry.S @@ -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 diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c index 487bffb36f5e..72764356d308 100644 --- a/arch/sparc/kernel/process_32.c +++ b/arch/sparc/kernel/process_32.c @@ -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; -- 2.34.1