From: Al Viro Date: Mon, 10 Sep 2012 02:03:42 +0000 (-0400) Subject: alpha: switch to generic kernel_thread() X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=cba1ec7e88a0257eb13e84d170a93cd52b702562;p=linux-beck.git alpha: switch to generic kernel_thread() Signed-off-by: Al Viro --- diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index 9944dedee5b1..7da91246e279 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -20,6 +20,7 @@ config ALPHA select GENERIC_CMOS_UPDATE select GENERIC_STRNCPY_FROM_USER select GENERIC_STRNLEN_USER + select GENERIC_KERNEL_THREAD help The Alpha is a 64-bit general-purpose processor designed and marketed by the Digital Equipment Corporation of blessed memory, diff --git a/arch/alpha/include/asm/processor.h b/arch/alpha/include/asm/processor.h index e37b887b3d9f..6cb7fe85c4b5 100644 --- a/arch/alpha/include/asm/processor.h +++ b/arch/alpha/include/asm/processor.h @@ -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 *); -/* Create a kernel thread without removing it from tasklists. */ -extern long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); - unsigned long get_wchan(struct task_struct *p); #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc) diff --git a/arch/alpha/kernel/alpha_ksyms.c b/arch/alpha/kernel/alpha_ksyms.c index 15fa821d09cd..89566b346c0f 100644 --- a/arch/alpha/kernel/alpha_ksyms.c +++ b/arch/alpha/kernel/alpha_ksyms.c @@ -50,9 +50,6 @@ EXPORT_SYMBOL(alpha_read_fp_reg_s); EXPORT_SYMBOL(alpha_write_fp_reg); EXPORT_SYMBOL(alpha_write_fp_reg_s); -/* entry.S */ -EXPORT_SYMBOL(kernel_thread); - /* Networking helper routines. */ EXPORT_SYMBOL(csum_tcpudp_magic); EXPORT_SYMBOL(ip_compute_csum); diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S index 61ff145cab6e..421dccf273eb 100644 --- a/arch/alpha/kernel/entry.S +++ b/arch/alpha/kernel/entry.S @@ -609,59 +609,22 @@ ret_from_fork: .end ret_from_fork /* - * kernel_thread(fn, arg, clone_flags) + * ... and new kernel threads - here */ .align 4 - .globl kernel_thread - .ent kernel_thread -kernel_thread: - /* We can be called from a module. */ - ldgp $gp, 0($27) - .prologue 1 - subq $sp, SP_OFF+6*8, $sp - br $1, 2f /* load start address */ - - /* We've now "returned" from a fake system call. */ - unop - blt $0, 1f /* error? */ - ldi $1, 0x3fff - beq $20, 1f /* parent or child? */ - - bic $sp, $1, $8 /* in child. */ - jsr $26, ($27) + .globl ret_from_kernel_thread + .ent ret_from_kernel_thread +ret_from_kernel_thread: + mov $17, $16 + jsr $26, schedule_tail + mov $9, $27 + mov $10, $16 + jsr $26, ($9) ldgp $gp, 0($26) mov $0, $16 mov $31, $26 jmp $31, sys_exit - -1: ret /* in parent. */ - - .align 4 -2: /* Fake a system call stack frame, as we can't do system calls - from kernel space. Note that we store FN and ARG as they - need to be set up in the child for the call. Also store $8 - and $26 for use in the parent. */ - stq $31, SP_OFF($sp) /* ps */ - stq $1, SP_OFF+8($sp) /* pc */ - stq $gp, SP_OFF+16($sp) /* gp */ - stq $16, 136($sp) /* $27; FN for child */ - stq $17, SP_OFF+24($sp) /* $16; ARG for child */ - stq $8, 64($sp) /* $8 */ - stq $26, 128($sp) /* $26 */ - /* Avoid the HAE being gratuitously wrong, to avoid restoring it. */ - ldq $2, alpha_mv+HAE_CACHE - stq $2, 152($sp) /* HAE */ - - /* Shuffle FLAGS to the front; add CLONE_VM. */ - ldi $1, CLONE_VM|CLONE_UNTRACED - or $18, $1, $16 - bsr $26, sys_clone - - /* We don't actually care for a3 success widgetry in the kernel. - Not for positive errno values. */ - stq $0, 0($sp) /* $0 */ - br ret_to_kernel -.end kernel_thread +.end ret_from_kernel_thread /* diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c index 145473909199..6b33ecdbc534 100644 --- a/arch/alpha/kernel/process.c +++ b/arch/alpha/kernel/process.c @@ -259,33 +259,35 @@ alpha_vfork(struct pt_regs *regs) /* * Copy an alpha thread.. - * - * Note the "stack_offset" stuff: when returning to kernel mode, we need - * to have some extra stack-space for the kernel stack that still exists - * after the "ret_from_fork". When returning to user mode, we only want - * the space needed by the syscall stack frame (ie "struct pt_regs"). - * Use the passed "regs" pointer to determine how much space we need - * for a kernel fork(). */ int copy_thread(unsigned long clone_flags, unsigned long usp, - unsigned long unused, + unsigned long arg, struct task_struct * p, struct pt_regs * regs) { extern void ret_from_fork(void); + extern void ret_from_kernel_thread(void); struct thread_info *childti = task_thread_info(p); - struct pt_regs * childregs; - struct switch_stack * childstack, *stack; - unsigned long stack_offset, settls; - - stack_offset = PAGE_SIZE - sizeof(struct pt_regs); - if (!(regs->ps & 8)) - stack_offset = (PAGE_SIZE-1) & (unsigned long) regs; - childregs = (struct pt_regs *) - (stack_offset + PAGE_SIZE + task_stack_page(p)); - + struct pt_regs *childregs = task_pt_regs(p); + struct switch_stack *childstack, *stack; + unsigned long settls; + + childstack = ((struct switch_stack *) childregs) - 1; + if (unlikely(!regs)) { + /* kernel thread */ + memset(childstack, 0, + sizeof(struct switch_stack) + sizeof(struct pt_regs)); + childstack->r26 = (unsigned long) ret_from_kernel_thread; + childstack->r9 = usp; /* function */ + childstack->r10 = arg; + childregs->hae = alpha_mv.hae_cache, + childti->pcb.usp = 0; + childti->pcb.ksp = (unsigned long) childstack; + childti->pcb.flags = 1; /* set FEN, clear everything else */ + return 0; + } *childregs = *regs; settls = regs->r20; childregs->r0 = 0; @@ -293,7 +295,6 @@ copy_thread(unsigned long clone_flags, unsigned long usp, childregs->r20 = 1; /* OSF/1 has some strange fork() semantics. */ regs->r20 = 0; stack = ((struct switch_stack *) regs) - 1; - childstack = ((struct switch_stack *) childregs) - 1; *childstack = *stack; childstack->r26 = (unsigned long) ret_from_fork; childti->pcb.usp = usp;