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Diffstat (limited to 'cpu/activity.hh')
-rw-r--r-- | cpu/activity.hh | 124 |
1 files changed, 0 insertions, 124 deletions
diff --git a/cpu/activity.hh b/cpu/activity.hh deleted file mode 100644 index 2c0df5efb..000000000 --- a/cpu/activity.hh +++ /dev/null @@ -1,124 +0,0 @@ -/* - * Copyright (c) 2006 The Regents of The University of Michigan - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are - * met: redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer; - * redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution; - * neither the name of the copyright holders nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -#ifndef __CPU_ACTIVITY_HH__ -#define __CPU_ACTIVITY_HH__ - -#include "base/timebuf.hh" -#include "base/trace.hh" - -/** - * ActivityRecorder helper class that informs the CPU if it can switch - * over to being idle or not. It works by having a time buffer as - * long as any time buffer in the CPU, and the CPU and all of its - * stages inform the ActivityRecorder when they write to any time - * buffer. The ActivityRecorder marks a 1 in the "0" slot of the time - * buffer any time a stage writes to a time buffer, and it advances - * its time buffer at the same time as all other stages. The - * ActivityRecorder also records if a stage has activity to do next - * cycle. The recorder keeps a count of these two. Thus any time the - * count is non-zero, there is either communication still in flight, - * or activity that still must be done, meaning that the CPU can not - * idle. If count is zero, then the CPU can safely idle as it has no - * more outstanding work to do. - */ -class ActivityRecorder { - public: - ActivityRecorder(int num_stages, int longest_latency, int count); - - /** Records that there is activity this cycle. */ - void activity(); - - /** Advances the activity buffer, decrementing the activityCount - * if active communication just left the time buffer, and - * determining if there is no activity. - */ - void advance(); - - /** Marks a stage as active. */ - void activateStage(const int idx); - - /** Deactivates a stage. */ - void deactivateStage(const int idx); - - /** Returns how many things are active within the recorder. */ - int getActivityCount() { return activityCount; } - - /** Sets the count to a starting value. Can be used to disable - * the idling option. - */ - void setActivityCount(int count) - { activityCount = count; } - - /** Returns if the CPU should be active. */ - bool active() { return activityCount; } - - /** Clears the time buffer and the activity count. */ - void reset(); - - /** Debug function to dump the contents of the time buffer. */ - void dump(); - - /** Debug function to ensure that the activity count matches the - * contents of the time buffer. - */ - void validate(); - - private: - /** Time buffer that tracks if any cycles has active communication - * in them. It should be as long as the longest communication - * latency in the system. Each time any time buffer is written, - * the activity buffer should also be written to. The - * activityBuffer is advanced along with all the other time - * buffers, so it should have a 1 somewhere in it only if there - * is active communication in a time buffer. - */ - TimeBuffer<bool> activityBuffer; - - /** Longest latency time buffer in the CPU. */ - int longestLatency; - - /** Tracks how many stages and cycles of time buffer have - * activity. Stages increment this count when they switch to - * active, and decrement it when they switch to - * inactive. Whenever a cycle that previously had no information - * is written in the time buffer, this is incremented. When a - * cycle that had information exits the time buffer due to age, - * this count is decremented. When the count is 0, there is no - * activity in the CPU, and it can be descheduled. - */ - int activityCount; - - /** Number of stages that can be marked as active or inactive. */ - int numStages; - - /** Records which stages are active/inactive. */ - bool *stageActive; -}; - -#endif // __CPU_ACTIVITY_HH__ |