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[PATCH] m68k: convert thread flags to use bit fields

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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>
This commit is contained in:
Roman Zippel
2005-11-13 16:06:59 -08:00
committed by Linus Torvalds
parent abd03753bd
commit 3b66a1edb0
8 changed files with 71 additions and 177 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
arch/m68k/kernel/asm-offsets.c
View File

@@ -25,11 +25,6 @@ int main(void)
DEFINE(TASK_STATE, offsetof(struct task_struct, state));
DEFINE(TASK_FLAGS, offsetof(struct task_struct, flags));
DEFINE(TASK_PTRACE, offsetof(struct task_struct, ptrace));
DEFINE(TASK_WORK, offsetof(struct task_struct, thread.work));
DEFINE(TASK_NEEDRESCHED, offsetof(struct task_struct, thread.work.need_resched));
DEFINE(TASK_SYSCALL_TRACE, offsetof(struct task_struct, thread.work.syscall_trace));
DEFINE(TASK_SIGPENDING, offsetof(struct task_struct, thread.work.sigpending));
DEFINE(TASK_NOTIFY_RESUME, offsetof(struct task_struct, thread.work.notify_resume));
DEFINE(TASK_THREAD, offsetof(struct task_struct, thread));
DEFINE(TASK_INFO, offsetof(struct task_struct, thread.info));
DEFINE(TASK_MM, offsetof(struct task_struct, mm));

78
arch/m68k/kernel/entry.S
View File

@@ -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 @@ ENTRY(buserr)
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 @@ ENTRY(trap)
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 @@ ENTRY(ret_from_fork)
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 @@ ret_from_signal:
addql #4,%sp
1:
#endif
jra ret_from_exception
jra .Lret_from_exception
ENTRY(system_call)
SAVE_ALL_SYS
@@ -120,30 +119,34 @@ ENTRY(system_call)
| 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 @@ ret_from_exception:
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 @@ ret_from_interrupt:
/* 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

15
arch/m68k/kernel/ptrace.c
View File

@@ -109,7 +109,7 @@ static inline void singlestep_disable(struct task_struct *child)
{
unsigned long tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
put_reg(child, PT_SR, tmp);
child->thread.work.delayed_trace = 0;
clear_tsk_thread_flag(child, TIF_DELAYED_TRACE);
}
/*
@@ -118,7 +118,7 @@ static inline void singlestep_disable(struct task_struct *child)
void ptrace_disable(struct task_struct *child)
{
singlestep_disable(child);
child->thread.work.syscall_trace = 0;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
@@ -198,9 +198,9 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
goto out_eio;
if (request == PTRACE_SYSCALL)
child->thread.work.syscall_trace = ~0;
set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
else
child->thread.work.syscall_trace = 0;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
child->exit_code = data;
singlestep_disable(child);
wake_up_process(child);
@@ -223,10 +223,10 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
if (!valid_signal(data))
goto out_eio;
child->thread.work.syscall_trace = 0;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16);
put_reg(child, PT_SR, tmp);
child->thread.work.delayed_trace = 1;
set_tsk_thread_flag(child, TIF_DELAYED_TRACE);
child->exit_code = data;
/* give it a chance to run. */
@@ -288,9 +288,6 @@ out_eio:
asmlinkage void syscall_trace(void)
{
if (!current->thread.work.delayed_trace &&
!current->thread.work.syscall_trace)
return;
ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
? 0x80 : 0));
/*