I have a question regarding the recvtiming() function in bus.cc. Please refer 
to the following code snippet:

if (dest == Packet::Broadcast) {
        port = findPort(pkt->getAddr(), pkt->getSrc());
        if (timingSnoop(pkt, port ? port : interfaces[pkt->getSrc()])) {
            bool success;

            pkt->flags |= SNOOP_COMMIT;
            success = timingSnoop(pkt, port ? port : .....

Does the destination field in packet is set to Broadcast each time a cache miss 
occurs? If not, under what scenario is the destination of packet a Broadcast. 
Looks like timingsnoop() is being called on events other than a cache miss ! 
Also, any ideas how I can track the information that the current packet needs 
to occupy the bus because of an earlier cache miss.


---- Original message ----
>Date: Sun, 18 Nov 2007 16:23:00 -0800
>From: "Steve Reinhardt" <[EMAIL PROTECTED]>  
>Subject: Re: [m5-users] Changing Bus Latency for Packet  
>To: "M5 users mailing list" <m5-users@m5sim.org>
>
>Just to be clear: ticks are just ticks, the smallest discrete unit of
>time.  They aren't processor cycles.  It may just so happen that your
>processor cycle time is 1 tick, but that's not a given.  Particularly
>in FS mode we use 1 tick == 1ps, and we've been trying to move there
>in SE mode too.
>
>The 'clock' field in the bus object is the number of ticks in a bus
>clock.  You should not be adding values that are not a multiple of
>clock to tickNextIdle, as then the bus may start processing events at
>times that are not bus clock edges... this won't necessarily break
>things but it doesn't make sense from a timing perspective.
>
>I don't see any reason why your code change would lead to negative
>numbers; you should run under gdb to figure that kind of thing out.
>
>Steve
>
>On Nov 18, 2007 3:52 PM, Shoaib Akram <[EMAIL PROTECTED]> wrote:
>> The -ve number was an issue with something else ! However, if I add 
>> busCycles, the traces are what is expected. But if I insert processor cycles 
>> e.g., tickNextIdle+=78, the traces are not in accordance with what is 
>> expected and even the total numebr of cycles are less than without adding 
>> extra cycles. I am looking for the right way to insert processor cycles 
>> (ticks rather than numCycles) for a certain packet?
>>
>>
>> ---- Original message ----
>> >Date: Sun, 18 Nov 2007 16:47:23 -0600 (CST)
>> >From: Shoaib Akram <[EMAIL PROTECTED]>
>> >Subject: [m5-users] Changing Bus Latency for Packet
>> >To: m5-users@m5sim.org
>> >
>> >I want to have extra bus cycles added for certain type of packets. If I add 
>> >a busCycle, tickNextIdle+=clock, something anomalous happens. At one point 
>> >after first 4000 cycles, the tickNextIdle gets calculated to a negative 
>> >number, which the following trace on bus shows: Please suggest whats the 
>> >right way to add busCycles. If I add processor cycles (tickNextIdle+=100), 
>> >I dont have negative numbers but the traces show results not expected !
>> >
>> >1001: system.membus: recvTiming: packet src 1 dest -1 addr 0x140 cmd ReadReq
>> >1001: system.membus:   found addr 0x140 on device 0
>> >1001: system.membus: The bus is now occupied from tick 1001  to 4000
>> >1002: system.membus: recvTiming: packet src 0 dest 1 addr 0x140 cmd ReadResp
>> >1002: Event_10318838: Waiting on retry
>> >4000: system.membus: Received a retry
>> >4000: system.membus: Sending a retry
>> >4000: system.membus: recvTiming: packet src 0 dest 1 addr 0x140 cmd ReadResp
>> >4000: system.membus: The bus is now occupied from tick 4000 to -243651592
>> >
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