mips: switch to generic kernel_thread()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index dba9390d37cf2c0d1672ca6dfb2b1453fb4294cf..ede301f9c88b0fbb8c387b0ecf42fb5899b03a63 100644 (file)
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -40,6 +40,7 @@ config MIPS
        select HAVE_MOD_ARCH_SPECIFIC
        select MODULES_USE_ELF_REL
        select MODULES_USE_ELF_RELA if 64BIT
+       select GENERIC_KERNEL_THREAD
 
 menu "Machine selection"
 

diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h
index 5e33fabe354de7e12e11dc4f64aa5d0be7464090..d28c41e0887c584a8c869eb266138d3545bad157 100644 (file)
--- a/arch/mips/include/asm/processor.h
+++ b/arch/mips/include/asm/processor.h
@@ -310,8 +310,6 @@ struct task_struct;
 /* Free all resources held by a thread. */
 #define release_thread(thread) do { } while(0)
 
-extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
 extern unsigned long thread_saved_pc(struct task_struct *tsk);
 
 /*

diff --git a/arch/mips/kernel/entry.S b/arch/mips/kernel/entry.S
index a6c133212003ed96537e6f950ec71c59d98559fb..aab6997b8f47a32eecc9379752921a9d3d950d80 100644 (file)
--- a/arch/mips/kernel/entry.S
+++ b/arch/mips/kernel/entry.S
@@ -65,6 +65,13 @@ need_resched:
        b       need_resched
 #endif
 
+FEXPORT(ret_from_kernel_thread)
+       jal     schedule_tail           # a0 = struct task_struct *prev
+       move    a0, s1
+       jal     s0
+       li      a0, 0
+       j       sys_exit
+
 FEXPORT(ret_from_fork)
        jal     schedule_tail           # a0 = struct task_struct *prev
 

diff --git a/arch/mips/kernel/mips_ksyms.c b/arch/mips/kernel/mips_ksyms.c
index 3fc1691110dc52f82e8ec1271054c1411c122658..2d9304c2b54cb0e8508e3a9dd397486ac977d1bb 100644 (file)
--- a/arch/mips/kernel/mips_ksyms.c
+++ b/arch/mips/kernel/mips_ksyms.c
@@ -32,8 +32,6 @@ EXPORT_SYMBOL(memset);
 EXPORT_SYMBOL(memcpy);
 EXPORT_SYMBOL(memmove);
 
-EXPORT_SYMBOL(kernel_thread);
-
 /*
  * Functions that operate on entire pages.  Mostly used by memory management.
  */

diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index e9a5fd7277f4fd580172a5630d604e443c60513d..d13720ac656f40d4cb71a71da54e15aba56c2b22 100644 (file)
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -84,6 +84,7 @@ void __noreturn cpu_idle(void)
 }
 
 asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
 
 void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp)
 {
@@ -113,7 +114,7 @@ void flush_thread(void)
 }
 
 int copy_thread(unsigned long clone_flags, unsigned long usp,
-       unsigned long unused, struct task_struct *p, struct pt_regs *regs)
+       unsigned long arg, struct task_struct *p, struct pt_regs *regs)
 {
        struct thread_info *ti = task_thread_info(p);
        struct pt_regs *childregs;
@@ -136,19 +137,30 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
        childregs = (struct pt_regs *) childksp - 1;
        /*  Put the stack after the struct pt_regs.  */
        childksp = (unsigned long) childregs;
+       p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1);
+       if (unlikely(p->flags & PF_KTHREAD)) {
+               unsigned long status = p->thread.cp0_status;
+               memset(childregs, 0, sizeof(struct pt_regs));
+               ti->addr_limit = KERNEL_DS;
+               p->thread.reg16 = usp; /* fn */
+               p->thread.reg17 = arg;
+               p->thread.reg29 = childksp;
+               p->thread.reg31 = (unsigned long) ret_from_kernel_thread;
+#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
+               status = (status & ~(ST0_KUP | ST0_IEP | ST0_IEC)) |
+                        ((status & (ST0_KUC | ST0_IEC)) << 2);
+#else
+               status |= ST0_EXL;
+#endif
+               childregs->cp0_status = status;
+               return 0;
+       }
        *childregs = *regs;
        childregs->regs[7] = 0; /* Clear error flag */
-
        childregs->regs[2] = 0; /* Child gets zero as return value */
+       childregs->regs[29] = usp;
+       ti->addr_limit = USER_DS;
 
-       if (childregs->cp0_status & ST0_CU0) {
-               childregs->regs[28] = (unsigned long) ti;
-               childregs->regs[29] = childksp;
-               ti->addr_limit = KERNEL_DS;
-       } else {
-               childregs->regs[29] = usp;
-               ti->addr_limit = USER_DS;
-       }
        p->thread.reg29 = (unsigned long) childregs;
        p->thread.reg31 = (unsigned long) ret_from_fork;
 
@@ -156,7 +168,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
         * New tasks lose permission to use the fpu. This accelerates context
         * switching for most programs since they don't use the fpu.
         */
-       p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1);
        childregs->cp0_status &= ~(ST0_CU2|ST0_CU1);
 
 #ifdef CONFIG_MIPS_MT_SMTC
@@ -221,35 +232,6 @@ int dump_task_fpu(struct task_struct *t, elf_fpregset_t *fpr)
        return 1;
 }
 
-/*
- * Create a kernel thread
- */
-static void __noreturn kernel_thread_helper(void *arg, int (*fn)(void *))
-{
-       do_exit(fn(arg));
-}
-
-long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
-{
-       struct pt_regs regs;
-
-       memset(&regs, 0, sizeof(regs));
-
-       regs.regs[4] = (unsigned long) arg;
-       regs.regs[5] = (unsigned long) fn;
-       regs.cp0_epc = (unsigned long) kernel_thread_helper;
-       regs.cp0_status = read_c0_status();
-#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
-       regs.cp0_status = (regs.cp0_status & ~(ST0_KUP | ST0_IEP | ST0_IEC)) |
-                         ((regs.cp0_status & (ST0_KUC | ST0_IEC)) << 2);
-#else
-       regs.cp0_status |= ST0_EXL;
-#endif
-
-       /* Ok, create the new process.. */
-       return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
-}
-
 /*
  *
  */