stack_dist.cc revision 10995:a114e2712642
1/* 2 * Copyright (c) 2015 ARM Limited 3 * All rights reserved 4 * 5 * The license below extends only to copyright in the software and shall 6 * not be construed as granting a license to any other intellectual 7 * property including but not limited to intellectual property relating 8 * to a hardware implementation of the functionality of the software 9 * licensed hereunder. You may use the software subject to the license 10 * terms below provided that you ensure that this notice is replicated 11 * unmodified and in its entirety in all distributions of the software, 12 * modified or unmodified, in source code or in binary form. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions are 16 * met: redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer; 18 * redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution; 21 * neither the name of the copyright holders nor the names of its 22 * contributors may be used to endorse or promote products derived from 23 * this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 * 37 * Authors: Andreas Sandberg 38 */ 39 40#include "mem/probes/stack_dist.hh" 41 42#include "params/StackDistProbe.hh" 43#include "sim/system.hh" 44 45StackDistProbe::StackDistProbe(StackDistProbeParams *p) 46 : BaseMemProbe(p), 47 lineSize(p->line_size), 48 disableLinearHists(p->disable_linear_hists), 49 disableLogHists(p->disable_log_hists), 50 calc(p->verify) 51{ 52 fatal_if(p->system->cacheLineSize() > p->line_size, 53 "The stack distance probe must use a cache line size that is " 54 "larger or equal to the system's cahce line size."); 55} 56 57void 58StackDistProbe::regStats() 59{ 60 const StackDistProbeParams *p( 61 dynamic_cast<const StackDistProbeParams *>(params())); 62 assert(p); 63 64 using namespace Stats; 65 66 readLinearHist 67 .init(p->linear_hist_bins) 68 .name(name() + ".readLinearHist") 69 .desc("Reads linear distribution") 70 .flags(disableLinearHists ? nozero : pdf); 71 72 readLogHist 73 .init(p->log_hist_bins) 74 .name(name() + ".readLogHist") 75 .desc("Reads logarithmic distribution") 76 .flags(disableLogHists ? nozero : pdf); 77 78 writeLinearHist 79 .init(p->linear_hist_bins) 80 .name(name() + ".writeLinearHist") 81 .desc("Writes linear distribution") 82 .flags(disableLinearHists ? nozero : pdf); 83 84 writeLogHist 85 .init(p->log_hist_bins) 86 .name(name() + ".writeLogHist") 87 .desc("Writes logarithmic distribution") 88 .flags(disableLogHists ? nozero : pdf); 89 90 infiniteSD 91 .name(name() + ".infinity") 92 .desc("Number of requests with infinite stack distance") 93 .flags(nozero); 94} 95 96void 97StackDistProbe::handleRequest(const PacketPtr &pkt) 98{ 99 // only capturing read and write requests (which allocate in the 100 // cache) 101 if (!pkt->isRead() && !pkt->isWrite()) 102 return; 103 104 // Align the address to a cache line size 105 const Addr aligned_addr(roundDown(pkt->getAddr(), lineSize)); 106 107 // Calculate the stack distance 108 const uint64_t sd(calc.calcStackDistAndUpdate(aligned_addr).first); 109 if (sd == StackDistCalc::Infinity) { 110 infiniteSD++; 111 return; 112 } 113 114 // Sample the stack distance of the address in linear bins 115 if (!disableLinearHists) { 116 if (pkt->isRead()) 117 readLinearHist.sample(sd); 118 else 119 writeLinearHist.sample(sd); 120 } 121 122 if (!disableLogHists) { 123 int sd_lg2 = sd == 0 ? 1 : floorLog2(sd); 124 125 // Sample the stack distance of the address in log bins 126 if (pkt->isRead()) 127 readLogHist.sample(sd_lg2); 128 else 129 writeLogHist.sample(sd_lg2); 130 } 131} 132 133 134StackDistProbe * 135StackDistProbeParams::create() 136{ 137 return new StackDistProbe(this); 138} 139