Subject: Re: [PATCH 2/3] powerpc, ptrace: Add new ptrace request macros for transactional memory

From: Anshuman Khandual <[email-masked]>
Date: Mon, 28 Apr 2014 16:00:33 +0530

On 04/26/2014 05:12 AM, Pedro Alves wrote:
> On 04/02/2014 08:02 AM, Anshuman Khandual wrote:
>> This patch adds following new sets of ptrace request macros for transactional
>> memory expanding the existing ptrace ABI on PowerPC.
>>
>> 	/* TM special purpose registers */
>> 	PTRACE_GETTM_SPRREGS
>> 	PTRACE_SETTM_SPRREGS
>>
>> 	/* TM checkpointed GPR registers */
>> 	PTRACE_GETTM_CGPRREGS
>> 	PTRACE_SETTM_CGPRREGS
>>
>> 	/* TM checkpointed FPR registers */
>> 	PTRACE_GETTM_CFPRREGS
>> 	PTRACE_SETTM_CFPRREGS
>>
>> 	/* TM checkpointed VMX registers */
>> 	PTRACE_GETTM_CVMXREGS
>> 	PTRACE_SETTM_CVMXREGS
> 
> Urgh, we're _still_ adding specialized register specific calls?
> Why aren't these exported as new register sets, accessible through
> PTRACE_GETREGSET /  PTRACE_SETREGSET?  That's supposed to be the
> Modern Way to do things.

All these new register sets can be accessed through PTRACE_GETREGSET
/SETREGSET requests with the new NT_PPC_* core note types added in the
previous patch. PowerPC already has some register specific ptrace
requests, so thought of adding some new requests for transactional
memory purpose. But yes these are redundant and can be dropped.