src/jemalloc/src/quarantine.c

   1 #define JEMALLOC_QUARANTINE_C_
   2 #include "jemalloc/internal/jemalloc_internal.h"
   3
   4 /*
   5  * Quarantine pointers close to NULL are used to encode state information that
   6  * is used for cleaning up during thread shutdown.
   7  */
   8 #define QUARANTINE_STATE_REINCARNATED   ((quarantine_t *)(uintptr_t)1)
   9 #define QUARANTINE_STATE_PURGATORY      ((quarantine_t *)(uintptr_t)2)
  10 #define QUARANTINE_STATE_MAX            QUARANTINE_STATE_PURGATORY
  11
  12 /******************************************************************************/
  13 /* Function prototypes for non-inline static functions. */
  14
  15 static quarantine_t     *quarantine_grow(tsd_t *tsd, quarantine_t *quarantine);
  16 static void     quarantine_drain_one(tsd_t *tsd, quarantine_t *quarantine);
  17 static void     quarantine_drain(tsd_t *tsd, quarantine_t *quarantine,
  18     size_t upper_bound);
  19
  20 /******************************************************************************/
  21
  22 static quarantine_t *
  23 quarantine_init(tsd_t *tsd, size_t lg_maxobjs)
  24 {
  25         quarantine_t *quarantine;
  26
  27         assert(tsd_nominal(tsd));
  28
  29         quarantine = (quarantine_t *)iallocztm(tsd, offsetof(quarantine_t, objs)
  30             + ((ZU(1) << lg_maxobjs) * sizeof(quarantine_obj_t)), false,
  31             tcache_get(tsd, true), true, NULL);
  32         if (quarantine == NULL)
  33                 return (NULL);
  34         quarantine->curbytes = 0;
  35         quarantine->curobjs = 0;
  36         quarantine->first = 0;
  37         quarantine->lg_maxobjs = lg_maxobjs;
  38
  39         return (quarantine);
  40 }
  41
  42 void
  43 quarantine_alloc_hook_work(tsd_t *tsd)
  44 {
  45         quarantine_t *quarantine;
  46
  47         if (!tsd_nominal(tsd))
  48                 return;
  49
  50         quarantine = quarantine_init(tsd, LG_MAXOBJS_INIT);
  51         /*
  52          * Check again whether quarantine has been initialized, because
  53          * quarantine_init() may have triggered recursive initialization.
  54          */
  55         if (tsd_quarantine_get(tsd) == NULL)
  56                 tsd_quarantine_set(tsd, quarantine);
  57         else
  58                 idalloctm(tsd, quarantine, tcache_get(tsd, false), true);
  59 }
  60
  61 static quarantine_t *
  62 quarantine_grow(tsd_t *tsd, quarantine_t *quarantine)
  63 {
  64         quarantine_t *ret;
  65
  66         ret = quarantine_init(tsd, quarantine->lg_maxobjs + 1);
  67         if (ret == NULL) {
  68                 quarantine_drain_one(tsd, quarantine);
  69                 return (quarantine);
  70         }
  71
  72         ret->curbytes = quarantine->curbytes;
  73         ret->curobjs = quarantine->curobjs;
  74         if (quarantine->first + quarantine->curobjs <= (ZU(1) <<
  75             quarantine->lg_maxobjs)) {
  76                 /* objs ring buffer data are contiguous. */
  77                 memcpy(ret->objs, &quarantine->objs[quarantine->first],
  78                     quarantine->curobjs * sizeof(quarantine_obj_t));
  79         } else {
  80                 /* objs ring buffer data wrap around. */
  81                 size_t ncopy_a = (ZU(1) << quarantine->lg_maxobjs) -
  82                     quarantine->first;
  83                 size_t ncopy_b = quarantine->curobjs - ncopy_a;
  84
  85                 memcpy(ret->objs, &quarantine->objs[quarantine->first], ncopy_a
  86                     * sizeof(quarantine_obj_t));
  87                 memcpy(&ret->objs[ncopy_a], quarantine->objs, ncopy_b *
  88                     sizeof(quarantine_obj_t));
  89         }
  90         idalloctm(tsd, quarantine, tcache_get(tsd, false), true);
  91
  92         tsd_quarantine_set(tsd, ret);
  93         return (ret);
  94 }
  95
  96 static void
  97 quarantine_drain_one(tsd_t *tsd, quarantine_t *quarantine)
  98 {
  99         quarantine_obj_t *obj = &quarantine->objs[quarantine->first];
 100         assert(obj->usize == isalloc(obj->ptr, config_prof));
 101         idalloctm(tsd, obj->ptr, NULL, false);
 102         quarantine->curbytes -= obj->usize;
 103         quarantine->curobjs--;
 104         quarantine->first = (quarantine->first + 1) & ((ZU(1) <<
 105             quarantine->lg_maxobjs) - 1);
 106 }
 107
 108 static void
 109 quarantine_drain(tsd_t *tsd, quarantine_t *quarantine, size_t upper_bound)
 110 {
 111
 112         while (quarantine->curbytes > upper_bound && quarantine->curobjs > 0)
 113                 quarantine_drain_one(tsd, quarantine);
 114 }
 115
 116 void
 117 quarantine(tsd_t *tsd, void *ptr)
 118 {
 119         quarantine_t *quarantine;
 120         size_t usize = isalloc(ptr, config_prof);
 121
 122         cassert(config_fill);
 123         assert(opt_quarantine);
 124
 125         if ((quarantine = tsd_quarantine_get(tsd)) == NULL) {
 126                 idalloctm(tsd, ptr, NULL, false);
 127                 return;
 128         }
 129         /*
 130          * Drain one or more objects if the quarantine size limit would be
 131          * exceeded by appending ptr.
 132          */
 133         if (quarantine->curbytes + usize > opt_quarantine) {
 134                 size_t upper_bound = (opt_quarantine >= usize) ? opt_quarantine
 135                     - usize : 0;
 136                 quarantine_drain(tsd, quarantine, upper_bound);
 137         }
 138         /* Grow the quarantine ring buffer if it's full. */
 139         if (quarantine->curobjs == (ZU(1) << quarantine->lg_maxobjs))
 140                 quarantine = quarantine_grow(tsd, quarantine);
 141         /* quarantine_grow() must free a slot if it fails to grow. */
 142         assert(quarantine->curobjs < (ZU(1) << quarantine->lg_maxobjs));
 143         /* Append ptr if its size doesn't exceed the quarantine size. */
 144         if (quarantine->curbytes + usize <= opt_quarantine) {
 145                 size_t offset = (quarantine->first + quarantine->curobjs) &
 146                     ((ZU(1) << quarantine->lg_maxobjs) - 1);
 147                 quarantine_obj_t *obj = &quarantine->objs[offset];
 148                 obj->ptr = ptr;
 149                 obj->usize = usize;
 150                 quarantine->curbytes += usize;
 151                 quarantine->curobjs++;
 152                 if (config_fill && unlikely(opt_junk_free)) {
 153                         /*
 154                          * Only do redzone validation if Valgrind isn't in
 155                          * operation.
 156                          */
 157                         if ((!config_valgrind || likely(!in_valgrind))
 158                             && usize <= SMALL_MAXCLASS)
 159                                 arena_quarantine_junk_small(ptr, usize);
 160                         else
 161                                 memset(ptr, 0x5a, usize);
 162                 }
 163         } else {
 164                 assert(quarantine->curbytes == 0);
 165                 idalloctm(tsd, ptr, NULL, false);
 166         }
 167 }
 168
 169 void
 170 quarantine_cleanup(tsd_t *tsd)
 171 {
 172         quarantine_t *quarantine;
 173
 174         if (!config_fill)
 175                 return;
 176
 177         quarantine = tsd_quarantine_get(tsd);
 178         if (quarantine != NULL) {
 179                 quarantine_drain(tsd, quarantine, 0);
 180                 idalloctm(tsd, quarantine, tcache_get(tsd, false), true);
 181                 tsd_quarantine_set(tsd, NULL);
 182         }
 183 }