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Subject: Re: [PATCH 07/15] powerpc/watchpoint: Get watchpoint count
 dynamically while disabling them
To:     Christophe Leroy <christophe.leroy@c-s.fr>
Cc:     mpe@ellerman.id.au, mikey@neuling.org, apopple@linux.ibm.com,
        paulus@samba.org, npiggin@gmail.com,
        naveen.n.rao@linux.vnet.ibm.com, peterz@infradead.org,
        jolsa@kernel.org, oleg@redhat.com, fweisbec@gmail.com,
        mingo@kernel.org, linuxppc-dev@lists.ozlabs.org,
        linux-kernel@vger.kernel.org,
        Ravi Bangoria <ravi.bangoria@linux.ibm.com>
References: <20200309085806.155823-1-ravi.bangoria@linux.ibm.com>
 <20200309085806.155823-8-ravi.bangoria@linux.ibm.com>
 <c73b77fd-b983-2c5c-75bb-4b2f47a94d92@c-s.fr>
From:   Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Date:   Wed, 18 Mar 2020 12:27:24 +0530
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On 3/17/20 4:02 PM, Christophe Leroy wrote:
> 
> 
> Le 09/03/2020 à 09:57, Ravi Bangoria a écrit :
>> Instead of disabling only one watchpooint, get num of available
>> watchpoints dynamically and disable all of them.
>>
>> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
>> ---
>>   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 980ac7d9f267..ec61e2b7195c 100644
>> --- a/arch/powerpc/include/asm/hw_breakpoint.h
>> +++ b/arch/powerpc/include/asm/hw_breakpoint.h
>> @@ -75,14 +75,13 @@ 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()) {
> 
> I think this test should go into nr_wp_slots() which should return zero when no breakpoint is available.

Seems possible. Will change it in next version.

Thanks,
Ravi