Re: [PATCH v5 05/19] arm64: Add support for trace synchronization barrier

From: Marc Zyngier
Date: Wed Mar 24 2021 - 09:50:39 EST


On Wed, 24 Mar 2021 09:39:13 +0000,
Suzuki K Poulose <suzuki.poulose@xxxxxxx> wrote:
>
> On 23/03/2021 18:21, Catalin Marinas wrote:
> > Hi Suzuki?
> >
> > On Tue, Mar 23, 2021 at 12:06:33PM +0000, Suzuki K Poulose wrote:
> >> tsb csync synchronizes the trace operation of instructions.
> >> The instruction is a nop when FEAT_TRF is not implemented.
> >>
> >> Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> >> Cc: Mike Leach <mike.leach@xxxxxxxxxx>
> >> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> >> Cc: Will Deacon <will.deacon@xxxxxxx>
> >> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> >
> > How do you plan to merge these patches? If they go via the coresight
> > tree:
> >
>
> Ideally all of this should go via the CoreSight tree to have the
> dependencies solved at one place. But there are some issues :
>
> If this makes to 5.13 queue for CoreSight,
>
> 1) CoreSight next is based on rc2 at the moment and we have fixes gone
> into rc3 and later, which this series will depend on. (We could move
> the next tree forward to a later rc to solve this).
>
> 2) There could be conflicts with the kvmarm tree for the KVM host
> changes (That has dependency on the TRBE definitions patch).
>
> If it doesn't make to 5.13 queue, it would be good to have this patch,
> the TRBE defintions and the KVM host patches queued for 5.13 (not sure
> if this is acceptable) and we could rebase the CoreSight changes on 5.13
> and push it to next release.
>
> I am open for other suggestions.
>
> Marc, Mathieu,
>
> Thoughts ?

I was planning to take the first two patches in 5.12 as fixes (they
are queued already, and would hopefully land in -rc5). If that doesn't
fit with the plan, please let me know ASAP.

Thanks,

M.

--
Without deviation from the norm, progress is not possible.