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Subject: Re: [RFC PATCH 05/12] [WIP] powerpc/tm: Reclaim/recheckpoint on
 entry/exit
From: Michael Neuling <mikey@neuling.org>
To: Cyril Bur <cyrilbur@gmail.com>, benh@kernel.crashing.org,
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Date: Tue, 20 Feb 2018 16:25:00 +1100
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> > > @@ -1055,6 +1082,8 @@ void restore_tm_state(struct pt_regs *regs)
> > >  	msr_diff =3D current->thread.ckpt_regs.msr & ~regs->msr;
> > >  	msr_diff &=3D MSR_FP | MSR_VEC | MSR_VSX;
> > > =20
> > > +	tm_recheckpoint(&current->thread);
> > > +
> >=20
> > So why do we do tm_recheckpoint at all? Shouldn't most of the tm_blah c=
ode go
> > away in process.c after all this?
> >=20
>=20
> I'm not sure I follow, we need to recheckpoint because we're going back
> to userspace? Or would you rather calling the tm.S code directly from
> the exception return path?

Yeah, I was thinking the point of this series was.  We do tm_reclaim right =
on
entry and tm_recheckpoint right on exit. =20

The bits in between (ie. the tm_blah() calls process.c) would mostly go awa=
y.


> Yes, I hope we'll be able to have a fairly big cleanup commit of tm_
> code in process.c at the end of this series.

Yep, agreed.

Mikey