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gem5: more analysis
This commit is contained in:
Ciro Santilli 六四事件 法轮功
349
README.adoc
349
README.adoc
@@ -12934,14 +12934,16 @@ Not all times need to have an associated event: if a given time has no events, g
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Important examples of events include:
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Important examples of events include:
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* CPU ticks
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* CPU ticks
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* TODO peripherals and memory
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* peripherals and memory
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At the beginning of simulation, gem5 sets up exactly two events:
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At <<gem5-event-queue-atomicsimplecpu-syscall-emulation-freestanding-example-analysis>> we see for example that at the beginning of an <<gem5-basesimplecpu,AtomicCPU>> simulation, gem5 sets up exactly two events:
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* the first CPU cycle
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* the first CPU cycle
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* one exit event at the end of time which triggers <<gem5-simulate-limit-reached>>
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* one exit event at the end of time which triggers <<gem5-simulate-limit-reached>>
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Tick events then get triggered one by one as simulation progresses, in addition to any other system events.
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Then, at the end of the callback of one tick event, another tick is scheduled.
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And so the simulation progresses tick by tick, until an exit event happens.
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The `EventQueue` class has one awesome `dump()` function that prints a human friendly representation of the queue, and can be easily called from GDB. TODO example.
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The `EventQueue` class has one awesome `dump()` function that prints a human friendly representation of the queue, and can be easily called from GDB. TODO example.
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@@ -13075,6 +13077,12 @@ def instantiate(ckpt_dir=None):
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for obj in root.descendants(): obj.initState()
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for obj in root.descendants(): obj.initState()
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....
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....
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and this gets called from the toplevel Python scripts e.g. forsefpy `configs/common/Simulation.py` does:
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....
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m5.instantiate(checkpoint_dir)
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....
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As we can see, `initState` is just one stage of generic `SimObject` initialization. `root.descendants()` goes over the entire `SimObject` tree calling `initState()`.
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As we can see, `initState` is just one stage of generic `SimObject` initialization. `root.descendants()` goes over the entire `SimObject` tree calling `initState()`.
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Finally, we see that `initState` is part of the `SimObject` C++ API:
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Finally, we see that `initState` is part of the `SimObject` C++ API:
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@@ -13207,15 +13215,16 @@ TODO: analyze better what each of the memory event mean. For now, we have just c
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./run \
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./run \
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--arch aarch64 \
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--arch aarch64 \
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--emulator gem5 \
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--emulator gem5 \
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--gem5-build-type gem5 \
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--userland userland/arch/aarch64/freestanding/linux/hello.S \
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--userland userland/arch/aarch64/freestanding/linux/hello.S \
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--trace Event,ExecAll \
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--trace Event,ExecAll,FmtFlag \
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--trace-stdout \
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--trace-stdout \
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-- \
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-- \
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--cpu-type TimingSimpleCPU \
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--cpu-type TimingSimpleCPU \
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;
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;
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....
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....
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As of LKMC 9bfbff244d713de40e5686bd370eadb20cf78c7b + 1 the log is now much more complex.
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As of LKMC 78ce2dabe18ef1d87dc435e5bc9369ce82e8d6d2 gem5 12c917de54145d2d50260035ba7fa614e25317a3 the log is now much more complex.
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Here is an abridged version with:
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Here is an abridged version with:
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@@ -13225,38 +13234,85 @@ Here is an abridged version with:
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because all that happens in between is exactly the same as the first two instructions and therefore boring:
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because all that happens in between is exactly the same as the first two instructions and therefore boring:
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....
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....
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0: system.cpu.wrapped_function_event: EventFunctionWrapped event scheduled @ 0
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0: Event: system.cpu.wrapped_function_event: EventFunctionWrapped 43 scheduled @ 0
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**** REAL SIMULATION ****
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**** REAL SIMULATION ****
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0: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped event scheduled @ 7786250
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0: Event: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped 14 scheduled @ 7786250
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0: system.mem_ctrls_1.wrapped_function_event: EventFunctionWrapped event scheduled @ 7786250
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0: Event: system.mem_ctrls_1.wrapped_function_event: EventFunctionWrapped 20 scheduled @ 7786250
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0: Event_74: generic event scheduled @ 0
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0: Event: Event_74: generic 74 scheduled @ 0
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info: Entering event queue @ 0. Starting simulation...
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info: Entering event queue @ 0. Starting simulation...
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0: Event_74: generic event rescheduled @ 18446744073709551615
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0: Event: Event_74: generic 74 rescheduled @ 18446744073709551615
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0: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 0
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0: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped event scheduled @ 1000
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0: Event: system.cpu.wrapped_function_event: EventFunctionWrapped 43 executed @ 0
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0: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped event scheduled @ 0
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0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 0
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0: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 46250
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0: Event: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped 60 scheduled @ 1000
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0: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 5000
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0: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped event scheduled @ 0
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0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 executed @ 0
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46250: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped event scheduled @ 74250
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0: Event: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped 12 scheduled @ 0
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74250: system.membus.slave[1]-RespPacketQueue.wrapped_function_event: EventFunctionWrapped event scheduled @ 77000
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0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 10 scheduled @ 46250
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74250: system.membus.respLayer1.wrapped_function_event: EventFunctionWrapped event scheduled @ 77000
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0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 5000
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77000: Event_40: Timing CPU icache tick event scheduled @ 77000
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77000: system.cpu A0 T0 : @asm_main_after_prologue : movz x0, #1, #0 : IntAlu : D=0x0000000000000001 flags=(IsInteger)
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0: Event: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped 12 executed @ 0
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77000: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 77000
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0: Event: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped 15 scheduled @ 0
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77000: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped event scheduled @ 78000
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77000: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 95750
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0: Event: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped 15 executed @ 0
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77000: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 77000
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95750: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped event scheduled @ 123750
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1000: Event: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped 60 executed @ 1000
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123750: system.membus.slave[1]-RespPacketQueue.wrapped_function_event: EventFunctionWrapped event scheduled @ 126000
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123750: system.membus.respLayer1.wrapped_function_event: EventFunctionWrapped event scheduled @ 126000
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5000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 executed @ 5000
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126000: Event_40: Timing CPU icache tick event scheduled @ 126000
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[...]
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46250: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 10 executed @ 46250
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469000: system.cpu A0 T0 : @asm_main_after_prologue+28 : svc #0x0 : IntAlu : flags=(IsSerializeAfter|IsNonSpeculative|IsSyscall)
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46250: Event: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 8 scheduled @ 74250
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469000: Event_75: generic event scheduled @ 469000
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74250: Event: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 8 executed @ 74250
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74250: Event: system.membus.slave[1]-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 64 scheduled @ 77000
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74250: Event: system.membus.respLayer1.wrapped_function_event: EventFunctionWrapped 65 scheduled @ 77000
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77000: Event: system.membus.respLayer1.wrapped_function_event: EventFunctionWrapped 65 executed @ 77000
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77000: Event: system.membus.slave[1]-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 64 executed @ 77000
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77000: Event: Event_40: Timing CPU icache tick 40 scheduled @ 77000
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77000: Event: Event_40: Timing CPU icache tick 40 executed @ 77000
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77000: ExecEnable: system.cpu: A0 T0 : @asm_main_after_prologue : movz x0, #1, #0 : IntAlu : D=0x0000000000000001 flags=(IsInteger)
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77000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 77000
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77000: Event: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped 60 scheduled @ 78000
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77000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 executed @ 77000
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77000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 10 scheduled @ 95750
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77000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 77000
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77000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 executed @ 77000
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78000: Event: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped 60 executed @ 78000
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95750: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 10 executed @ 95750
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95750: Event: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 8 scheduled @ 123750
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123750: Event: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 8 executed @ 123750
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123750: Event: system.membus.slave[1]-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 64 scheduled @ 126000
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123750: Event: system.membus.respLayer1.wrapped_function_event: EventFunctionWrapped 65 scheduled @ 126000
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126000: Event: system.membus.respLayer1.wrapped_function_event: EventFunctionWrapped 65 executed @ 126000
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126000: Event: system.membus.slave[1]-RespPacketQueue.wrapped_function_event: EventFunctionWrapped 64 executed @ 126000
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126000: Event: Event_40: Timing CPU icache tick 40 scheduled @ 126000
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126000: Event: Event_40: Timing CPU icache tick 40 executed @ 126000
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126000: ExecEnable: system.cpu: A0 T0 : @asm_main_after_prologue+4 : adr x1, #28 : IntAlu : D=0x0000000000400098 flags=(IsInteger)
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126000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 126000
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126000: Event: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped 60 scheduled @ 127000
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126000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 executed @ 126000
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126000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 10 scheduled @ 144750
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126000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 126000
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126000: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 executed @ 126000
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[...]
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469000: ExecEnable: system.cpu: A0 T0 : @asm_main_after_prologue+28 : svc #0x0 : IntAlu : flags=(IsSerializeAfter|IsNonSpeculative|IsSyscall)
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469000: Event: Event_75: generic 75 scheduled @ 469000
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469000: Event: Event_75: generic 75 executed @ 469000
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....
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....
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`0: system.cpu.wrapped_function_event` schedule the initial tick, much like for for `AtomicSimpleCPU`. This time however, it is not a tick, but rather a fetch event that gets scheduled:
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The first event scheduled:
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....
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0: Event: system.cpu.wrapped_function_event: EventFunctionWrapped 43 scheduled @ 0
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....
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schedules the initial tick, much like for for `AtomicSimpleCPU`.
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This time however, it is not a tick, but rather a fetch event that gets scheduled:
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....
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....
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TimingSimpleCPU::activateContext(ThreadID thread_num)
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TimingSimpleCPU::activateContext(ThreadID thread_num)
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@@ -13274,11 +13330,36 @@ TimingSimpleCPU::activateContext(ThreadID thread_num)
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schedule(fetchEvent, clockEdge(Cycles(0)));
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schedule(fetchEvent, clockEdge(Cycles(0)));
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....
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....
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and just like for `AtomicSimpleCPU` it comes from the `initState` call:
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....
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EventManager::schedule
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TimingSimpleCPU::activateContext
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SimpleThread::activate
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Process::initState
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ArmProcess64::initState
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ArmLinuxProcess64::initState
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....
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We have a fetch instead of a tick here compared to `AtomicSimpleCPU`, because in the timing CPU we must first get the instruction opcode from DRAM, which takes some cycles to return!
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We have a fetch instead of a tick here compared to `AtomicSimpleCPU`, because in the timing CPU we must first get the instruction opcode from DRAM, which takes some cycles to return!
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By looking at the source, we see that fetchEvent runs `TimingSimpleCPU::fetch`.
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By looking at the source, we see that `fetchEvent` runs `TimingSimpleCPU::fetch`.
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`0: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped event scheduled @ 7786250`: from GDB we see that it comes from `DRAMCtrl::startup` in `mem/dram_ctrl.cc` which contains:
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The next event line is:
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....
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0: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped event scheduled @ 7786250
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....
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From GDB we see that it comes from `DRAMCtrl::startup` in `mem/dram_ctrl.cc` with a short backtrace:
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....
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EventManager::schedule
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DRAMCtrl::Rank::startup
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DRAMCtrl::startup (this
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....
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which contains:
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....
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....
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void
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void
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@@ -13322,6 +13403,25 @@ DRAMCtrl::Rank::startup(Tick ref_tick)
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}
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}
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....
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....
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`startup` itself a `SimObject` method exposed to Python and called from `simulate` in `src/python/m5/simulate.py`:
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....
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def simulate(*args, **kwargs):
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global need_startup
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if need_startup:
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root = objects.Root.getInstance()
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for obj in root.descendants(): obj.startup()
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....
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where `simulate` happens after `m5.instantiate`, and both are called directly from the toplevel scripts, e.g. for se.py in `configs/common/Simulation.py`:
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....
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def run(options, root, testsys, cpu_class):
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...
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exit_event = m5.simulate()
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....
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By looking up some variable definitions in the source, we now we see some memory parameters clearly:
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By looking up some variable definitions in the source, we now we see some memory parameters clearly:
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* ranks: `std::vector<DRAMCtrl::Rank*>` with 2 elements. TODO why do we have 2? What does it represent? Likely linked to <<gem5-config-ini,`config.ini`>> at `system.mem_ctrls.ranks_per_channel=2`
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* ranks: `std::vector<DRAMCtrl::Rank*>` with 2 elements. TODO why do we have 2? What does it represent? Likely linked to <<gem5-config-ini,`config.ini`>> at `system.mem_ctrls.ranks_per_channel=2`
|
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@@ -13356,47 +13456,96 @@ So we realize that we are going into deep DRAM modelling, more detail that a mer
|
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|
||||||
`curTick() + tREFI - tRP = 0 + 7800000 - 13750 = 7786250` which is when that `refreshEvent` was scheduled. Our simulation ends way before that point however, so we will never know what it did thank God.
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`curTick() + tREFI - tRP = 0 + 7800000 - 13750 = 7786250` which is when that `refreshEvent` was scheduled. Our simulation ends way before that point however, so we will never know what it did thank God.
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`0: Event_74: generic event scheduled @ 0` and `0: Event_74: generic event rescheduled @ 18446744073709551615`: schedule the final exit event, same as for `AtomicSimpleCPU`
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The next event:
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||||||
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|
||||||
The next interesting event is:
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|
||||||
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|
||||||
....
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....
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system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 0
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0: Event: system.mem_ctrls_1.wrapped_function_event: EventFunctionWrapped 20 scheduled @ 7786250
|
||||||
....
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....
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which comes from:
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must be coming from the `startup` of the second memory controller object.
|
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||||||
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`se.py` allocates the memory controllers via `configs/common/MemConfig.py`:
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|
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....
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....
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#0 Trace::OstreamLogger::logMessage
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|
||||||
#1 void Trace::Logger::dprintf
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def config_mem(options, system):
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#2 Event::trace
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#3 EventQueue::schedule
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...
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#4 EventManager::schedule
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#5 DRAMCtrl::addToReadQueue
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opt_mem_channels = options.mem_channels
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#6 DRAMCtrl::recvTimingReq
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#7 DRAMCtrl::MemoryPort::recvTimingReq
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...
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#8 TimingRequestProtocol::sendReq
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#9 MasterPort::sendTimingReq
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nbr_mem_ctrls = opt_mem_channels
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#10 CoherentXBar::recvTimingReq
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||||||
#11 CoherentXBar::CoherentXBarSlavePort::recvTimingReq(Packet*))
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...
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#12 TimingRequestProtocol::sendReq
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#13 MasterPort::sendTimingReq
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for r in system.mem_ranges:
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||||||
#14 TimingSimpleCPU::sendFetch
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for i in range(nbr_mem_ctrls):
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#15 TimingSimpleCPU::FetchTranslation::finish
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mem_ctrl = create_mem_ctrl(cls, r, i, nbr_mem_ctrls, intlv_bits,
|
||||||
#16 ArmISA::TLB::translateComplete
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intlv_size)
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#17 ArmISA::TLB::translateTiming
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||||||
#18 ArmISA::TLB::translateTiming
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...
|
||||||
#19 TimingSimpleCPU::fetch
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#20 TimingSimpleCPU::<lambda()>::operator()(void)
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mem_ctrls.append(mem_ctrl)
|
||||||
#21 std::_Function_handler<void(), TimingSimpleCPU::TimingSimpleCPU(TimingSimpleCPUParams*)::<lambda()> >
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||||||
#22 std::function<void)>::operator()() const
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||||||
#23 EventFunctionWrapper::process
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|
||||||
#24 EventQueue::serviceOne
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|
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#25 doSimLoop
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#26 simulate
|
|
||||||
....
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....
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|
||||||
From the trace, we see that we are already running from the event queue. Therefore, we must have been running a previously scheduled event, and the previous event logs, the only such event is `0: system.cpu.wrapped_function_event: EventFunctionWrapped event scheduled @ 0` which scheduled a memory fetch!
|
but TODO that loop happens only once, why there are two such objects then?
|
||||||
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|
||||||
|
The next events are:
|
||||||
|
|
||||||
|
....
|
||||||
|
0: Event: Event_74: generic 74 scheduled @ 0
|
||||||
|
0: Event: Event_74: generic 74 rescheduled @ 18446744073709551615
|
||||||
|
....
|
||||||
|
|
||||||
|
From the timing we know what that one is: the end of time exit event, like for `AtomicSimpleCPU`.
|
||||||
|
|
||||||
|
The next event logs are:
|
||||||
|
|
||||||
|
....
|
||||||
|
0: Event: system.cpu.wrapped_function_event: EventFunctionWrapped 43 executed @ 0
|
||||||
|
0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 0
|
||||||
|
0: Event: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped 60 scheduled @ 1000
|
||||||
|
....
|
||||||
|
|
||||||
|
The first line shows that event ID `43` is now executing: we had previously seen event `43` get scheduled and had analyzed it to be the initial fetch.
|
||||||
|
|
||||||
|
The second line, is an execution. The event loop has started, an magic initialization schedulings are not happening anymore: now every event is being scheduled from another event:
|
||||||
|
|
||||||
|
....
|
||||||
|
Trace::OstreamLogger::logMessage
|
||||||
|
void Trace::Logger::dprintf
|
||||||
|
Event::trace
|
||||||
|
EventQueue::schedule
|
||||||
|
EventManager::schedule
|
||||||
|
DRAMCtrl::addToReadQueue
|
||||||
|
DRAMCtrl::recvTimingReq
|
||||||
|
DRAMCtrl::MemoryPort::recvTimingReq
|
||||||
|
TimingRequestProtocol::sendReq
|
||||||
|
MasterPort::sendTimingReq
|
||||||
|
CoherentXBar::recvTimingReq
|
||||||
|
CoherentXBar::CoherentXBarSlavePort::recvTimingReq(Packet*))
|
||||||
|
TimingRequestProtocol::sendReq
|
||||||
|
MasterPort::sendTimingReq
|
||||||
|
TimingSimpleCPU::sendFetch
|
||||||
|
TimingSimpleCPU::FetchTranslation::finish
|
||||||
|
ArmISA::TLB::translateComplete
|
||||||
|
ArmISA::TLB::translateTiming
|
||||||
|
ArmISA::TLB::translateTiming
|
||||||
|
TimingSimpleCPU::fetch
|
||||||
|
TimingSimpleCPU::<lambda()>::operator()(void)
|
||||||
|
std::_Function_handler<void(), TimingSimpleCPU::TimingSimpleCPU(TimingSimpleCPUParams*)::<lambda()> >
|
||||||
|
std::function<void)>::operator()() const
|
||||||
|
EventFunctionWrapper::process
|
||||||
|
EventQueue::serviceOne
|
||||||
|
doSimLoop
|
||||||
|
simulate
|
||||||
|
....
|
||||||
|
|
||||||
|
From the trace, we see that we are already running from the event queue under `TimingSimpleCPU::fetch` as expected.
|
||||||
|
|
||||||
|
This must be the CPU fetching an instruction from the memory system to execute it!
|
||||||
|
|
||||||
From the backtrace we see the tortuous path that the data request takes, going through:
|
From the backtrace we see the tortuous path that the data request takes, going through:
|
||||||
|
|
||||||
@@ -13404,7 +13553,7 @@ From the backtrace we see the tortuous path that the data request takes, going t
|
|||||||
* `CoherentXBar`
|
* `CoherentXBar`
|
||||||
* `DRAMCtrl`
|
* `DRAMCtrl`
|
||||||
|
|
||||||
The scheduling happens at frame `#5`:
|
The scheduling happens at frame `DRAMCtrl::addToReadQueue`:
|
||||||
|
|
||||||
....
|
....
|
||||||
// If we are not already scheduled to get a request out of the
|
// If we are not already scheduled to get a request out of the
|
||||||
@@ -13415,35 +13564,67 @@ The scheduling happens at frame `#5`:
|
|||||||
}
|
}
|
||||||
....
|
....
|
||||||
|
|
||||||
and from a quick source grep we see that `nextReqEvent` is a `DRAMCtrl::processNextReqEvent`.
|
and from a quick source grep we see that `nextReqEvent` is a `DRAMCtrl::processNextReqEvent`. From this we deduce that the DRAM has a request queue of some sort.
|
||||||
|
|
||||||
The next schedule:
|
The second schedule coming from the initial fetch is:
|
||||||
|
|
||||||
....
|
....
|
||||||
0: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped event scheduled @ 1000
|
0: Event: system.membus.reqLayer0.wrapped_function_event: EventFunctionWrapped 60 scheduled @ 1000
|
||||||
....
|
....
|
||||||
|
|
||||||
and does a `BaseXBar::Layer::releaseLayer` event.
|
and schedules a `BaseXBar::Layer::releaseLayer` event through:
|
||||||
|
|
||||||
This one is also coming from the request queue at `TimingSimpleCPU::fetch`. We deduce therefore that the single previous fetch event scheduled not one, but two events!
|
....
|
||||||
|
EventManager::schedule
|
||||||
|
BaseXBar::Layer<SlavePort, MasterPort>::occupyLayer
|
||||||
|
BaseXBar::Layer<SlavePort, MasterPort>::succeededTiming
|
||||||
|
CoherentXBar::recvTimingReq
|
||||||
|
CoherentXBar::CoherentXBarSlavePort::recvTimingReq
|
||||||
|
TimingRequestProtocol::sendReq
|
||||||
|
MasterPort::sendTimingReq
|
||||||
|
TimingSimpleCPU::sendFetch
|
||||||
|
TimingSimpleCPU::FetchTranslation
|
||||||
|
ArmISA::TLB::translateComplete
|
||||||
|
ArmISA::TLB::translateTiming
|
||||||
|
/build/ARM/arch/arm/tlb.cc
|
||||||
|
ArmISA::TLB::translateTiming
|
||||||
|
....
|
||||||
|
|
||||||
|
TODO what does this represent.
|
||||||
|
|
||||||
Now:
|
Now:
|
||||||
|
|
||||||
....
|
....
|
||||||
0: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped event scheduled @ 0
|
0: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped event scheduled @ 0
|
||||||
....
|
....
|
||||||
|
|
||||||
comes from the previously scheduled `DRAMCtrl::processNextReqEvent` and schedules `DRAMCtrl::Rank::processPrechargeEvent`.
|
comes from the previously scheduled `DRAMCtrl::processNextReqEvent` and schedules `DRAMCtrl::Rank::processPrechargeEvent`.
|
||||||
|
|
||||||
Now:
|
Then comes the execution:
|
||||||
|
|
||||||
....
|
....
|
||||||
0: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped event scheduled @ 46250
|
0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 executed @ 0
|
||||||
....
|
....
|
||||||
|
|
||||||
also runs from `DRAMCtrl::processNextReqEvent` and schedules a `DRAMCtrl::processRespondEvent`.
|
followed by three more schedules:
|
||||||
|
|
||||||
I'm getting bored, let's skip to the line that appears to matter for the first instruction:
|
....
|
||||||
|
0: Event: system.mem_ctrls_0.wrapped_function_event: EventFunctionWrapped 12 scheduled @ 0
|
||||||
|
EventManager::schedule(Event&, unsigned long)+0x30)[0x561af7237634]
|
||||||
|
DRAMCtrl::activateBank(DRAMCtrl::Rank&, DRAMCtrl::Bank&, unsigned long, unsigned int)+0xa7b)[0x561af7f24ced]
|
||||||
|
DRAMCtrl::doDRAMAccess(DRAMCtrl::DRAMPacket*)+0x2a0)[0x561af7f25602]
|
||||||
|
DRAMCtrl::processNextReqEvent()+0xdce)[0x561af7f27522]
|
||||||
|
|
||||||
|
0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 10 scheduled @ 46250
|
||||||
|
EventManager::schedule(Event&, unsigned long)+0x30)[0x561af7237634]
|
||||||
|
DRAMCtrl::processNextReqEvent()+0xf8c)[0x561af7f276e0]
|
||||||
|
|
||||||
|
0: Event: system.mem_ctrls.wrapped_function_event: EventFunctionWrapped 9 scheduled @ 5000
|
||||||
|
EventManager::schedule(Event&, unsigned long)+0x30)[0x561af7237634]
|
||||||
|
DRAMCtrl::processNextReqEvent()+0x1870)[0x561af7f27fc4]
|
||||||
|
....
|
||||||
|
|
||||||
|
TODO I got bored of DRAM modelling.
|
||||||
|
|
||||||
....
|
....
|
||||||
46250: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped event scheduled @ 74250
|
46250: system.mem_ctrls.port-RespPacketQueue.wrapped_function_event: EventFunctionWrapped event scheduled @ 74250
|
||||||
@@ -14460,6 +14641,12 @@ Programs under link:userland/cpp/[] are examples of https://en.wikipedia.org/wik
|
|||||||
|
|
||||||
* link:userland/cpp/empty.cpp[]
|
* link:userland/cpp/empty.cpp[]
|
||||||
* link:userland/cpp/hello.cpp[]
|
* link:userland/cpp/hello.cpp[]
|
||||||
|
* classes
|
||||||
|
** constructor
|
||||||
|
*** link:userland/cpp/initializer_list_constructor.cpp[]: documents stuff like `std::vector<int> v{0, 1};` and `std::initializer_list`
|
||||||
|
*** link:userland/cpp/most_vexing_parse.cpp[]: the most vexing parse is a famous constructor vs function declaration syntax gotcha!
|
||||||
|
**** https://en.wikipedia.org/wiki/Most_vexing_parse
|
||||||
|
**** http://stackoverflow.com/questions/180172/default-constructor-with-empty-brackets
|
||||||
* templates
|
* templates
|
||||||
** link:userland/cpp/template.cpp[]: basic example
|
** link:userland/cpp/template.cpp[]: basic example
|
||||||
** link:userland/cpp/template_class_with_static_member.cpp[]: https://stackoverflow.com/questions/3229883/static-member-initialization-in-a-class-template
|
** link:userland/cpp/template_class_with_static_member.cpp[]: https://stackoverflow.com/questions/3229883/static-member-initialization-in-a-class-template
|
||||||
@@ -14475,10 +14662,6 @@ Programs under link:userland/cpp/[] are examples of https://en.wikipedia.org/wik
|
|||||||
** associative
|
** associative
|
||||||
*** <<algorithms>> contains a benchmark comparison of different c++ containers
|
*** <<algorithms>> contains a benchmark comparison of different c++ containers
|
||||||
*** link:userland/cpp/set.cpp[]: `std::set` contains unique keys
|
*** link:userland/cpp/set.cpp[]: `std::set` contains unique keys
|
||||||
* Language madness
|
|
||||||
** link:userland/cpp/most_vexing_parse.cpp[]: the most vexing parse is a famous constructor vs function declaration syntax gotcha!
|
|
||||||
*** https://en.wikipedia.org/wiki/Most_vexing_parse
|
|
||||||
*** http://stackoverflow.com/questions/180172/default-constructor-with-empty-brackets
|
|
||||||
|
|
||||||
[[cpp-multithreading]]
|
[[cpp-multithreading]]
|
||||||
==== C++ multithreading
|
==== C++ multithreading
|
||||||
|
|||||||
14
run
14
run
@@ -517,17 +517,6 @@ Extra options to append at the end of the emulator command line.
|
|||||||
])
|
])
|
||||||
if self.env['userland_args'] is not None:
|
if self.env['userland_args'] is not None:
|
||||||
cmd.extend(['--options', self.env['userland_args'], LF])
|
cmd.extend(['--options', self.env['userland_args'], LF])
|
||||||
if not self.env['static']:
|
|
||||||
for path in self.env['userland_library_redirects']:
|
|
||||||
cmd.extend([
|
|
||||||
'--redirects',
|
|
||||||
'{}={}'.format(
|
|
||||||
os.sep + path,
|
|
||||||
os.path.join(self.env['userland_library_dir'], path)
|
|
||||||
),
|
|
||||||
LF
|
|
||||||
])
|
|
||||||
cmd.extend(['--interp-dir', self.env['userland_library_dir'], LF])
|
|
||||||
else:
|
else:
|
||||||
if self.env['gem5_script'] == 'fs':
|
if self.env['gem5_script'] == 'fs':
|
||||||
cmd.extend([
|
cmd.extend([
|
||||||
@@ -621,9 +610,6 @@ Extra options to append at the end of the emulator command line.
|
|||||||
),
|
),
|
||||||
LF
|
LF
|
||||||
])
|
])
|
||||||
if self.env['gem5_script'] == 'fs' or self.env['gem5_script'] == 'biglittle':
|
|
||||||
if self.env['gem5_bootloader'] is not None:
|
|
||||||
cmd.extend(['--bootloader', self.env['gem5_bootloader'], LF])
|
|
||||||
cmd.extend(['--mem-size', memory, LF])
|
cmd.extend(['--mem-size', memory, LF])
|
||||||
if self.env['gdb_wait']:
|
if self.env['gdb_wait']:
|
||||||
# https://stackoverflow.com/questions/49296092/how-to-make-gem5-wait-for-gdb-to-connect-to-reliably-break-at-start-kernel-of-th
|
# https://stackoverflow.com/questions/49296092/how-to-make-gem5-wait-for-gdb-to-connect-to-reliably-break-at-start-kernel-of-th
|
||||||
|
|||||||
Reference in New Issue
Block a user