2020-04-01 06:15:12

by Ravi Bangoria

Subject: [PATCH v2 07/16] powerpc/watchpoint: Get watchpoint count dynamically while disabling them

Instead of disabling only one watchpoint, get num of available
watchpoints dynamically and disable all of them.

Signed-off-by: Ravi Bangoria <[email protected]>
---
arch/powerpc/include/asm/hw_breakpoint.h | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/include/asm/hw_breakpoint.h b/arch/powerpc/include/asm/hw_breakpoint.h
index 4e4976c3248b..fae33c729ba9 100644
--- a/arch/powerpc/include/asm/hw_breakpoint.h
+++ b/arch/powerpc/include/asm/hw_breakpoint.h
@@ -78,14 +78,13 @@ extern void ptrace_triggered(struct perf_event *bp,
struct perf_sample_data *data, struct pt_regs *regs);
static inline void hw_breakpoint_disable(void)
{
- struct arch_hw_breakpoint brk;
-
- brk.address = 0;
- brk.type = 0;
- brk.len = 0;
- brk.hw_len = 0;
- if (ppc_breakpoint_available())
- __set_breakpoint(&brk, 0);
+ int i;
+ struct arch_hw_breakpoint null_brk = {0};
+
+ if (ppc_breakpoint_available()) {
+ for (i = 0; i < nr_wp_slots(); i++)
+ __set_breakpoint(&null_brk, i);
+ }
}
extern void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs);
int hw_breakpoint_handler(struct die_args *args);
--
2.21.1

2020-04-01 06:33:50

by Christophe Leroy

Subject: Re: [PATCH v2 07/16] powerpc/watchpoint: Get watchpoint count dynamically while disabling them

Le 01/04/2020 à 08:13, Ravi Bangoria a écrit :
> Instead of disabling only one watchpoint, get num of available
> watchpoints dynamically and disable all of them.
>
> Signed-off-by: Ravi Bangoria <[email protected]>
> ---
> arch/powerpc/include/asm/hw_breakpoint.h | 15 +++++++--------
> 1 file changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/hw_breakpoint.h b/arch/powerpc/include/asm/hw_breakpoint.h
> index 4e4976c3248b..fae33c729ba9 100644
> --- a/arch/powerpc/include/asm/hw_breakpoint.h
> +++ b/arch/powerpc/include/asm/hw_breakpoint.h
> @@ -78,14 +78,13 @@ extern void ptrace_triggered(struct perf_event *bp,
> struct perf_sample_data *data, struct pt_regs *regs);
> static inline void hw_breakpoint_disable(void)
> {
> - struct arch_hw_breakpoint brk;
> -
> - brk.address = 0;
> - brk.type = 0;
> - brk.len = 0;
> - brk.hw_len = 0;
> - if (ppc_breakpoint_available())
> - __set_breakpoint(&brk, 0);
> + int i;
> + struct arch_hw_breakpoint null_brk = {0};

Those declaration should be in the block unsigned them below.

> +
> + if (ppc_breakpoint_available()) {
> + for (i = 0; i < nr_wp_slots(); i++)
> + __set_breakpoint(&null_brk, i);
> + }

I would have had a preference to the following, but that's detail I guess:

int i;
struct arch_hw_breakpoint null_brk = {0};

if (!ppc_breakpoint_available())
return;

for (i = 0; i < nr_wp_slots(); i++)
__set_breakpoint(&null_brk, i);

> }
> extern void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs);
> int hw_breakpoint_handler(struct die_args *args);
>

Christophe

2020-04-01 09:21:59

by Ravi Bangoria

Subject: Re: [PATCH v2 07/16] powerpc/watchpoint: Get watchpoint count dynamically while disabling them

On 4/1/20 12:02 PM, Christophe Leroy wrote:
>
>
> Le 01/04/2020 à 08:13, Ravi Bangoria a écrit :
>> Instead of disabling only one watchpoint, get num of available
>> watchpoints dynamically and disable all of them.
>>
>> Signed-off-by: Ravi Bangoria <[email protected]>
>> ---
>>   arch/powerpc/include/asm/hw_breakpoint.h | 15 +++++++--------
>>   1 file changed, 7 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/hw_breakpoint.h b/arch/powerpc/include/asm/hw_breakpoint.h
>> index 4e4976c3248b..fae33c729ba9 100644
>> --- a/arch/powerpc/include/asm/hw_breakpoint.h
>> +++ b/arch/powerpc/include/asm/hw_breakpoint.h
>> @@ -78,14 +78,13 @@ extern void ptrace_triggered(struct perf_event *bp,
>>               struct perf_sample_data *data, struct pt_regs *regs);
>>   static inline void hw_breakpoint_disable(void)
>>   {
>> -    struct arch_hw_breakpoint brk;
>> -
>> -    brk.address = 0;
>> -    brk.type = 0;
>> -    brk.len = 0;
>> -    brk.hw_len = 0;
>> -    if (ppc_breakpoint_available())
>> -        __set_breakpoint(&brk, 0);
>> +    int i;
>> +    struct arch_hw_breakpoint null_brk = {0};
>
> Those declaration should be in the block unsigned them below.
>
>> +
>> +    if (ppc_breakpoint_available()) {
>> +        for (i = 0; i < nr_wp_slots(); i++)
>> +            __set_breakpoint(&null_brk, i);
>> +    }
>
> I would have had a preference to the following, but that's detail I guess:
>
>     int i;
>     struct arch_hw_breakpoint null_brk = {0};
>
>     if (!ppc_breakpoint_available())
>         return;
>
>     for (i = 0; i < nr_wp_slots(); i++)
>         __set_breakpoint(&null_brk, i);

This looks more better. Will change it.

Ravi