Re: [RFC PATCH 05/11] powerpc/tm: Function that updates the failure code

On Thu, 2018-09-27 at 17:58 -0300, Breno Leitao wrote:

Hi Mikey,

On 09/17/2018 10:29 PM, Michael Neuling wrote:

quoted

On Wed, 2018-09-12 at 16:40 -0300, Breno Leitao wrote:

quoted

Now the transaction reclaims happens very earlier in the trap handler, and
it is impossible to know precisely, at that early time, what should be set
as the failure cause for some specific cases, as, if the task will be
rescheduled, thus, the transaction abort case should be updated from
TM_CAUSE_MISC to TM_CAUSE_RESCHED, for example.

Please add comments to where this is used (in EXCEPTION_COMMON macro I
think)
that say this might happen.

Is it OK if I comment it in TM_KERNEL_ENTRY macro, since the failure cause
could be updated independently of the exception being execute, so, every call
to TM_KERNEL_ENTRY can have the cause overwritten.

Sure.

I.e. it does not matter if  the exception is a systemcall or a page fault,
the failure cause will be updated if there is a process reschedule after the
exception/syscall is handled.

Thank you