diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2012-09-10 18:03:41 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-09-30 23:03:03 -0400 |
| commit | 37fe5d41f6403b0ea84c1586548bf1b03f834af0 (patch) | |
| tree | 37e404af54f246a686dba85099187415591cde9d /arch/s390/kernel | |
| parent | 65f22a906e154e8086ed561904d09c3586de85f4 (diff) | |
| download | linux-37fe5d41f6403b0ea84c1586548bf1b03f834af0.tar.bz2 | |
s390: fold kernel_thread_helper() into ret_from_fork()
... and don't bother with syscall return path in case of kernel
threads.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'arch/s390/kernel')
| -rw-r--r-- | arch/s390/kernel/entry.S | 18 | ||||
| -rw-r--r-- | arch/s390/kernel/entry64.S | 16 | ||||
| -rw-r--r-- | arch/s390/kernel/process.c | 10 |
3 files changed, 28 insertions, 16 deletions
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index 6286985a1039..24de1cd3754b 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -331,14 +331,26 @@ ENTRY(ret_from_fork) l %r12,__LC_THREAD_INFO l %r13,__LC_SVC_NEW_PSW+4 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ? - jo 0f - st %r15,__PT_R15(%r11) # store stack pointer for new kthread -0: l %r1,BASED(.Lschedule_tail) + je 1f + l %r1,BASED(.Lschedule_tail) basr %r14,%r1 # call schedule_tail TRACE_IRQS_ON ssm __LC_SVC_NEW_PSW # reenable interrupts j sysc_tracenogo +1: # it's a kernel thread + st %r15,__PT_R15(%r11) # store stack pointer for new kthread + l %r1,BASED(.Lschedule_tail) + basr %r14,%r1 # call schedule_tail + TRACE_IRQS_ON + ssm __LC_SVC_NEW_PSW # reenable interrupts + lm %r9,%r11,__PT_R9(%r11) # load gprs +ENTRY(kernel_thread_starter) + la %r2,0(%r10) + basr %r14,%r9 + la %r2,0 + br %r11 # do_exit + # # kernel_execve function needs to deal with pt_regs that is not # at the usual place diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index 1f776f2edda5..39c84e65f74f 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -352,12 +352,22 @@ ENTRY(ret_from_fork) la %r11,STACK_FRAME_OVERHEAD(%r15) lg %r12,__LC_THREAD_INFO tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ? - jo 0f - stg %r15,__PT_R15(%r11) # store stack pointer for new kthread -0: brasl %r14,schedule_tail + je 1f + brasl %r14,schedule_tail TRACE_IRQS_ON ssm __LC_SVC_NEW_PSW # reenable interrupts j sysc_tracenogo +1: # it's a kernel thread + stg %r15,__PT_R15(%r11) # store stack pointer for new kthread + brasl %r14,schedule_tail + TRACE_IRQS_ON + ssm __LC_SVC_NEW_PSW # reenable interrupts + lmg %r9,%r11,__PT_R9(%r11) # load gprs +ENTRY(kernel_thread_starter) + la %r2,0(%r10) + basr %r14,%r9 + la %r2,0 + br %r11 # do_exit # # kernel_execve function needs to deal with pt_regs that is not diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index e540251e1dd1..2868a364ff94 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -98,16 +98,6 @@ void cpu_idle(void) extern void __kprobes kernel_thread_starter(void); -asm( - ".section .kprobes.text, \"ax\"\n" - ".global kernel_thread_starter\n" - "kernel_thread_starter:\n" - " la 2,0(10)\n" - " basr 14,9\n" - " la 2,0\n" - " br 11\n" - ".previous\n"); - int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) { struct pt_regs regs; |