Can point out the how the transitions that you are looking at? It seems to
me that the following transitions will take place --
NP --> ISS --> ISS_MB --> M/MT
--
Nilay
On Mon, 6 Feb 2012, Ricardo Quislant del Barrio wrote:
And what if other L1 has the block in the read set filter only?
Following the L2Cache transition table of "MESI_CMP_filter_directory"
protocol,
"unblock cancel" would be received and the block would be stated as "NP".
However, it could have been stated as SS if just the write set had been
checked.
Ricardo.
Nilay Vaish wrote:
That's probably to allow the requestor get exclusive access to the block if
no other L1 has it in the read set either.
--
Nilay
On Fri, 3 Feb 2012, Ricardo Quislant del Barrio wrote:
Hello everybody,
I would like to know why both read and write sets have to be checked when
an L1_GETS request gets the L2 cache
and the block is not present (NP) in there.
The annotation claims that it is for correctness.
Could anybody elaborate on this a bit more?
Why is it not enough to check write filters only?
Thank you very much,
Ricardo
// When L2 doesn't have block, need to send broadcasst to all L1s to check
appropriate filter(s)
transition(NP, L1_GETS, ISS) {
p_profileRequest;
f_profileRequestor;
qq_allocateL2CacheBlock;
ll_clearSharers;
// will mark as exclusive when we get unblocked with success
//nn_addSharer;
i_allocateTBE;
i_setTBEPhysicalAddress;
ss_recordGetSL1ID;
a_issueFetchToMemory;
// for correctness we need to query both read + write filters *<----*
a_checkL1ReadWriteFiltersExceptRequestor;
*<----*
uu_profileMiss;
jj_popL1RequestQueue;
}
--
Ricardo Quislant del Barrio
PhD Student
Dept. Computer Architecture Ph. +34 95 213 7236
University of Malaga Fax. +34 95 213 2790
ETSI Informatica, C. Teatinos e-mail. [email protected]
E-29071 Malaga, Spain
_______________________________________________
gem5-users mailing list
[email protected]
http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users
--
Ricardo Quislant del Barrio
PhD Student
Dept. Computer Architecture Ph. +34 95 213 7236
University of Malaga Fax. +34 95 213 2790
ETSI Informatica, C. Teatinos e-mail. [email protected]
E-29071 Malaga, Spain
_______________________________________________
gem5-users mailing list
[email protected]
http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users
