src/mem/PoolMalloc.cc

   1 /*
   2  * Copyright (C) 1996-2017 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /*
  10  * DEBUG: section 63    Low Level Memory Pool Management
  11  * AUTHOR: Alex Rousskov, Andres Kroonmaa, Robert Collins, Henrik Nordstrom
  12  */
  13
  14 #include "squid.h"
  15 #include "mem/PoolMalloc.h"
  16
  17 #include <cassert>
  18 #include <cstring>
  19
  20 extern time_t squid_curtime;
  21
  22 void *
  23 MemPoolMalloc::allocate()
  24 {
  25     void *obj = NULL;
  26     if (!freelist.empty()) {
  27         obj = freelist.top();
  28         freelist.pop();
  29     }
  30     if (obj) {
  31         --meter.idle;
  32         ++saved_calls;
  33     } else {
  34         if (doZero)
  35             obj = xcalloc(1, obj_size);
  36         else
  37             obj = xmalloc(obj_size);
  38         ++meter.alloc;
  39     }
  40     ++meter.inuse;
  41     return obj;
  42 }
  43
  44 void
  45 MemPoolMalloc::deallocate(void *obj, bool aggressive)
  46 {
  47     --meter.inuse;
  48     if (aggressive) {
  49         xfree(obj);
  50         --meter.alloc;
  51     } else {
  52         if (doZero)
  53             memset(obj, 0, obj_size);
  54         ++meter.idle;
  55         freelist.push(obj);
  56     }
  57 }
  58
  59 /* TODO extract common logic to MemAllocate */
  60 int
  61 MemPoolMalloc::getStats(MemPoolStats * stats, int accumulate)
  62 {
  63     if (!accumulate)    /* need skip memset for GlobalStats accumulation */
  64         memset(stats, 0, sizeof(MemPoolStats));
  65
  66     stats->pool = this;
  67     stats->label = objectType();
  68     stats->meter = &meter;
  69     stats->obj_size = obj_size;
  70     stats->chunk_capacity = 0;
  71
  72     stats->chunks_alloc += 0;
  73     stats->chunks_inuse += 0;
  74     stats->chunks_partial += 0;
  75     stats->chunks_free += 0;
  76
  77     stats->items_alloc += meter.alloc.currentLevel();
  78     stats->items_inuse += meter.inuse.currentLevel();
  79     stats->items_idle += meter.idle.currentLevel();
  80
  81     stats->overhead += sizeof(MemPoolMalloc) + strlen(objectType()) + 1;
  82
  83     return meter.inuse.currentLevel();
  84 }
  85
  86 int
  87 MemPoolMalloc::getInUseCount()
  88 {
  89     return meter.inuse.currentLevel();
  90 }
  91
  92 MemPoolMalloc::MemPoolMalloc(char const *aLabel, size_t aSize) : MemImplementingAllocator(aLabel, aSize)
  93 {
  94 }
  95
  96 MemPoolMalloc::~MemPoolMalloc()
  97 {
  98     assert(meter.inuse.currentLevel() == 0);
  99     clean(0);
 100 }
 101
 102 bool
 103 MemPoolMalloc::idleTrigger(int shift) const
 104 {
 105     return freelist.size() >> (shift ? 8 : 0);
 106 }
 107
 108 void
 109 MemPoolMalloc::clean(time_t)
 110 {
 111     while (!freelist.empty()) {
 112         void *obj = freelist.top();
 113         freelist.pop();
 114         --meter.idle;
 115         --meter.alloc;
 116         xfree(obj);
 117     }
 118 }
 119