[PATCH] m68k: convert thread flags to use bit fields
Remove task_work structure, use the standard thread flags functions and use
shifts in entry.S to test the thread flags. Add a few local labels to entry.S
to allow gas to generate short jumps.
Finally it changes a number of inline functions in thread_info.h to macros to
delay the current_thread_info() usage, which requires on m68k a structure
(task_struct) not yet defined at this point.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S
index 23ca60a..320fde0 100644
--- a/arch/m68k/kernel/entry.S
+++ b/arch/m68k/kernel/entry.S
@@ -44,9 +44,7 @@
#include <asm/asm-offsets.h>
-.globl system_call, buserr, trap
-.globl resume, ret_from_exception
-.globl ret_from_signal
+.globl system_call, buserr, trap, resume
.globl inthandler, sys_call_table
.globl sys_fork, sys_clone, sys_vfork
.globl ret_from_interrupt, bad_interrupt
@@ -58,7 +56,7 @@
movel %sp,%sp@- | stack frame pointer argument
bsrl buserr_c
addql #4,%sp
- jra ret_from_exception
+ jra .Lret_from_exception
ENTRY(trap)
SAVE_ALL_INT
@@ -66,7 +64,7 @@
movel %sp,%sp@- | stack frame pointer argument
bsrl trap_c
addql #4,%sp
- jra ret_from_exception
+ jra .Lret_from_exception
| After a fork we jump here directly from resume,
| so that %d1 contains the previous task
@@ -75,30 +73,31 @@
movel %d1,%sp@-
jsr schedule_tail
addql #4,%sp
- jra ret_from_exception
+ jra .Lret_from_exception
-badsys:
- movel #-ENOSYS,%sp@(PT_D0)
- jra ret_from_exception
-
-do_trace:
+do_trace_entry:
movel #-ENOSYS,%sp@(PT_D0) | needed for strace
subql #4,%sp
SAVE_SWITCH_STACK
jbsr syscall_trace
RESTORE_SWITCH_STACK
addql #4,%sp
- movel %sp@(PT_ORIG_D0),%d1
- movel #-ENOSYS,%d0
- cmpl #NR_syscalls,%d1
- jcc 1f
- jbsr @(sys_call_table,%d1:l:4)@(0)
-1: movel %d0,%sp@(PT_D0) | save the return value
- subql #4,%sp | dummy return address
+ movel %sp@(PT_ORIG_D0),%d0
+ cmpl #NR_syscalls,%d0
+ jcs syscall
+badsys:
+ movel #-ENOSYS,%sp@(PT_D0)
+ jra ret_from_syscall
+
+do_trace_exit:
+ subql #4,%sp
SAVE_SWITCH_STACK
jbsr syscall_trace
+ RESTORE_SWITCH_STACK
+ addql #4,%sp
+ jra .Lret_from_exception
-ret_from_signal:
+ENTRY(ret_from_signal)
RESTORE_SWITCH_STACK
addql #4,%sp
/* on 68040 complete pending writebacks if any */
@@ -111,7 +110,7 @@
addql #4,%sp
1:
#endif
- jra ret_from_exception
+ jra .Lret_from_exception
ENTRY(system_call)
SAVE_ALL_SYS
@@ -120,30 +119,34 @@
| save top of frame
movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)
- tstb %curptr@(TASK_SYSCALL_TRACE)
- jne do_trace
+ | syscall trace?
+ tstb %curptr@(TASK_INFO+TINFO_FLAGS+2)
+ jmi do_trace_entry
cmpl #NR_syscalls,%d0
jcc badsys
+syscall:
jbsr @(sys_call_table,%d0:l:4)@(0)
movel %d0,%sp@(PT_D0) | save the return value
-
+ret_from_syscall:
|oriw #0x0700,%sr
- movel %curptr@(TASK_WORK),%d0
+ movew %curptr@(TASK_INFO+TINFO_FLAGS+2),%d0
jne syscall_exit_work
1: RESTORE_ALL
syscall_exit_work:
btst #5,%sp@(PT_SR) | check if returning to kernel
bnes 1b | if so, skip resched, signals
- tstw %d0
- jeq do_signal_return
- tstb %d0
- jne do_delayed_trace
-
+ lslw #1,%d0
+ jcs do_trace_exit
+ jmi do_delayed_trace
+ lslw #8,%d0
+ jmi do_signal_return
pea resume_userspace
- jmp schedule
+ jra schedule
-ret_from_exception:
+
+ENTRY(ret_from_exception)
+.Lret_from_exception:
btst #5,%sp@(PT_SR) | check if returning to kernel
bnes 1f | if so, skip resched, signals
| only allow interrupts when we are really the last one on the
@@ -152,19 +155,18 @@
andw #ALLOWINT,%sr
resume_userspace:
- movel %curptr@(TASK_WORK),%d0
- lsrl #8,%d0
+ moveb %curptr@(TASK_INFO+TINFO_FLAGS+3),%d0
jne exit_work
1: RESTORE_ALL
exit_work:
| save top of frame
movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)
- tstb %d0
- jeq do_signal_return
-
+ lslb #1,%d0
+ jmi do_signal_return
pea resume_userspace
- jmp schedule
+ jra schedule
+
do_signal_return:
|andw #ALLOWINT,%sr
@@ -254,7 +256,7 @@
/* check if we need to do software interrupts */
tstl irq_stat+CPUSTAT_SOFTIRQ_PENDING
- jeq ret_from_exception
+ jeq .Lret_from_exception
pea ret_from_exception
jra do_softirq