> On Feb. 1, 2012, 8:39 a.m., Steve Reinhardt wrote:
> > src/cpu/o3/commit_impl.hh, line 1004
> > <http://reviews.gem5.org/r/1018/diff/1/?file=21617#file21617line1004>
> >
> >     Why is there a check for tid == 0 here?
> >     
> >     Also, where does the Alpha pal-mode check come from?  I don't see it in 
> > the original code.
> >
> 
> Nilay Vaish wrote:
>     Interrupts can only be handled by the thread with tid 0, so this
>     check is required. I think we can elide this check, if assume that
>     number of threads will always be set to 1. The Alpha pal-mode check
>     has been copied from the fetch stage. It might be possible that the
>     committed microop is marked non-delayed but is still a microop in the
>     pal-code. In this, case we do not want to handle the interrupt now.

Where does the tid 0 restriction come from?  It's probably moot since I don't 
know of any ISAs for which we support SMT in FS mode, but it seems odd that a 
"new" restriction is being introduced here in commit that wasn't here 
previously.  Similarly for the Alpha pal-mode check... why is it necessary to 
do this in commit now when it wasn't necessary before?


- Steve


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On Jan. 28, 2012, 9:01 p.m., Nilay Vaish wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> http://reviews.gem5.org/r/1018/
> -----------------------------------------------------------
> 
> (Updated Jan. 28, 2012, 9:01 p.m.)
> 
> 
> Review request for Default.
> 
> 
> Description
> -------
> 
> Changeset 8732:75e54d141aa0
> ---------------------------
> O3 CPU: Strengthen condition for handling interrupts
> The condition for handling interrupts is to check whether or not the cpu's
> instruction list is empty. As observed, this can lead to cases in which even
> though the instruction list is empty, interrupts are handled when they should
> not be. The condition is being strengthened so that interrupts get handled 
> only
> when the last committed microop did not had IsDelayedCommit set.
> 
> 
> Diffs
> -----
> 
>   src/cpu/o3/commit.hh 9d7c1dc54954 
>   src/cpu/o3/commit_impl.hh 9d7c1dc54954 
>   src/cpu/o3/fetch_impl.hh 9d7c1dc54954 
> 
> Diff: http://reviews.gem5.org/r/1018/diff/diff
> 
> 
> Testing
> -------
> 
> 
> Thanks,
> 
> Nilay Vaish
> 
>

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