Hi Jean-Michel,
Am 23.10.2024 um 18:53 schrieb Jean-Michel Hautbois:
Hi Michael,
On 23/10/2024 05:53, Michael Schmitz wrote:
Jean-Michel,
thanks for your patches!
Am 21.10.2024 um 22:44 schrieb Jean-Michel Hautbois:
The TRACE_IRQFLAGS_SUPPORT requires the architecture to call
trace_hardirqs_off() when interrupts are disabled and
trace_hardirqs_on() when they are enabled.
Add those calls to do_IRQ function.
You will also have to add these calls to the three sites in arch/m68k/
coldfire/head.S where interrupts are enabled or disabled.
Thanks for this ! I prepared a v2 with those calls added. I am wondering
Good -
if my second patch is ok, I think it is not, could you please review it
I'll have to read up on how arch_stack_walk is supposed to work - have
never seen that code before.
? There may already be something related to the stack in the assembly
part useful to implement arch_stack_walk() in a different way ?
I doubt it
Here:
ENTRY(system_call)
SAVE_ALL_SYS
move #0x2000,%sr /* enable intrs again */
GET_CURRENT(%d2)
and here:
ret_from_exception:
move #0x2700,%sr /* disable intrs */
btst #5,%sp@(PT_OFF_SR) /* check if returning to
kernel */
jeq Luser_return /* if so, skip resched,
signals */
and here:
Lwork_to_do:
movel %a0@(TINFO_FLAGS),%d1 /* get thread_info->flags */
move #0x2000,%sr /* enable intrs again */
btst #TIF_NEED_RESCHED,%d1
jne reschedule
There's one similar site in arch/m68k/kernel/head.S
(ret_from_exception) where interrupts are enabled that would need a
similar change, if you want to enable this for all m68k.
I won't be able to test it though ;-).
I see there are a few interrupts disabling in
arch/m68k/include/asm/entry.h too ?
Right - that's different in the coldfire stack save/restore macros. I
missed that before.
Looks like wherever SAVE_ALL_SYS, SAVE_ALL_INT and RESTORE_USER are
used, calls to trace_irqs_on/off() are required as well.
RESTORE_USER only restores the IPL in the CONFIG_COLDFIRE_SW_A7, which
makes this a little tricky ... you might have to add these calls to the
macros to get the correct behaviour.
Registers %d0-%d5 and %a0-%a2 are saved on the stack at this point and
can be clobbered if need be.
I don't know if they need to be clobbered...
I meant to say that if you need registers to prepare function arguments
for trace_irqs_on/off() on the stack, these can be used. But that may
not be necessary in this case.
Cheers,
Michael
Thanks,
JM
Cheers,
Michael
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@xxxxxxxxxx>
---
arch/m68k/Kconfig | 1 +
arch/m68k/kernel/irq.c | 2 ++
2 files changed, 3 insertions(+)
diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index
cc26df907bfe3c8143a931d259eceabb16af7411..ab3375475721fa63418c40d4ba6ac76679ebc77d
100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -39,6 +39,7 @@ config M68K
select OLD_SIGSUSPEND3
select UACCESS_MEMCPY if !MMU
select ZONE_DMA
+ select TRACE_IRQFLAGS_SUPPORT
config CPU_BIG_ENDIAN
def_bool y
diff --git a/arch/m68k/kernel/irq.c b/arch/m68k/kernel/irq.c
index
9ab4f550342e5de11c528f55781432675ffd66bf..74cf60ebbc4bca51f3caa4046dbd2bdb02355711
100644
--- a/arch/m68k/kernel/irq.c
+++ b/arch/m68k/kernel/irq.c
@@ -21,9 +21,11 @@ asmlinkage void do_IRQ(int irq, struct pt_regs *regs)
{
struct pt_regs *oldregs = set_irq_regs(regs);
+ trace_hardirqs_off();
irq_enter();
generic_handle_irq(irq);
irq_exit();
+ trace_hardirqs_on();
set_irq_regs(oldregs);
}
