[PATCH 11/31] Add debugger entry points for ARC

[PATCH 11/31] Add debugger entry points for ARC

[Jeffrey Merkey]

This patch series adds an export which can be set by system debuggers to
direct the hard lockup and soft lockup detector to trigger a breakpoint
exception and enter a debugger if one is active.  It is assumed that if
someone sets this variable, then an breakpoint handler of some sort will
be actively loaded or registered via the notify die handler chain.

This addition is extremely useful for debugging hard and soft lockups
real time and quickly from a console debugger.

Signed-off-by: Jeffrey Merkey <jeffmerkey@gmail.com>
---
 arch/arc/include/asm/kdebug.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arc/include/asm/kdebug.h b/arch/arc/include/asm/kdebug.h
index 3fbe6c4..f476ed7 100644
--- a/arch/arc/include/asm/kdebug.h
+++ b/arch/arc/include/asm/kdebug.h
@@ -16,4 +16,8 @@ enum die_val {
 	DIE_OOPS
 };
 
+static inline void arch_breakpoint(void)
+{
+	__asm__ __volatile__ ("trap_s	0x4\n");
+}
 #endif
-- 
1.8.3.1

Re: [PATCH 11/31] Add debugger entry points for ARC

[Vineet Gupta]

On Friday 29 January 2016 01:16 AM, Jeffrey Merkey wrote:
> This patch series adds an export which can be set by system debuggers to
> direct the hard lockup and soft lockup detector to trigger a breakpoint
> exception and enter a debugger if one is active.  It is assumed that if
> someone sets this variable, then an breakpoint handler of some sort will
> be actively loaded or registered via the notify die handler chain.
>
> This addition is extremely useful for debugging hard and soft lockups
> real time and quickly from a console debugger.
>
> Signed-off-by: Jeffrey Merkey <jeffmerkey@gmail.com>

To reduce duplication, maybe later this could be used to replace
arch_kgdb_breakpoint()

Acked-by: Vineet Gupta <vgupta@synopsys.com>

Re: [PATCH 11/31] Add debugger entry points for ARC

[Jeff Merkey]

On 2/1/16, Vineet Gupta <Vineet.Gupta1@synopsys.com> wrote:
> On Friday 29 January 2016 01:16 AM, Jeffrey Merkey wrote:
>> This patch series adds an export which can be set by system debuggers to
>> direct the hard lockup and soft lockup detector to trigger a breakpoint
>> exception and enter a debugger if one is active.  It is assumed that if
>> someone sets this variable, then an breakpoint handler of some sort will
>> be actively loaded or registered via the notify die handler chain.
>>
>> This addition is extremely useful for debugging hard and soft lockups
>> real time and quickly from a console debugger.
>>
>> Signed-off-by: Jeffrey Merkey <jeffmerkey@gmail.com>
>
> To reduce duplication, maybe later this could be used to replace
> arch_kgdb_breakpoint()
>
> Acked-by: Vineet Gupta <vgupta@synopsys.com>
>

You can drop this patch series, I am rethinking a better way to do this.

Jeff