drivers/gpu/drm/ttm/ttm_memory.c

   1 /**************************************************************************
   2  *
   3  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 #include "ttm/ttm_memory.h"
  29 #include <linux/spinlock.h>
  30 #include <linux/sched.h>
  31 #include <linux/wait.h>
  32 #include <linux/mm.h>
  33 #include <linux/module.h>
  34
  35 #define TTM_PFX "[TTM] "
  36 #define TTM_MEMORY_ALLOC_RETRIES 4
  37
  38 /**
  39  * At this point we only support a single shrink callback.
  40  * Extend this if needed, perhaps using a linked list of callbacks.
  41  * Note that this function is reentrant:
  42  * many threads may try to swap out at any given time.
  43  */
  44
  45 static void ttm_shrink(struct ttm_mem_global *glob, bool from_workqueue,
  46                        uint64_t extra)
  47 {
  48         int ret;
  49         struct ttm_mem_shrink *shrink;
  50         uint64_t target;
  51         uint64_t total_target;
  52
  53         spin_lock(&glob->lock);
  54         if (glob->shrink == NULL)
  55                 goto out;
  56
  57         if (from_workqueue) {
  58                 target = glob->swap_limit;
  59                 total_target = glob->total_memory_swap_limit;
  60         } else if (capable(CAP_SYS_ADMIN)) {
  61                 total_target = glob->emer_total_memory;
  62                 target = glob->emer_memory;
  63         } else {
  64                 total_target = glob->max_total_memory;
  65                 target = glob->max_memory;
  66         }
  67
  68         total_target = (extra >= total_target) ? 0 : total_target - extra;
  69         target = (extra >= target) ? 0 : target - extra;
  70
  71         while (glob->used_memory > target ||
  72                glob->used_total_memory > total_target) {
  73                 shrink = glob->shrink;
  74                 spin_unlock(&glob->lock);
  75                 ret = shrink->do_shrink(shrink);
  76                 spin_lock(&glob->lock);
  77                 if (unlikely(ret != 0))
  78                         goto out;
  79         }
  80 out:
  81         spin_unlock(&glob->lock);
  82 }
  83
  84 static void ttm_shrink_work(struct work_struct *work)
  85 {
  86         struct ttm_mem_global *glob =
  87             container_of(work, struct ttm_mem_global, work);
  88
  89         ttm_shrink(glob, true, 0ULL);
  90 }
  91
  92 int ttm_mem_global_init(struct ttm_mem_global *glob)
  93 {
  94         struct sysinfo si;
  95         uint64_t mem;
  96
  97         spin_lock_init(&glob->lock);
  98         glob->swap_queue = create_singlethread_workqueue("ttm_swap");
  99         INIT_WORK(&glob->work, ttm_shrink_work);
 100         init_waitqueue_head(&glob->queue);
 101
 102         si_meminfo(&si);
 103
 104         mem = si.totalram - si.totalhigh;
 105         mem *= si.mem_unit;
 106
 107         glob->max_memory = mem >> 1;
 108         glob->emer_memory = (mem >> 1) + (mem >> 2);
 109         glob->swap_limit = glob->max_memory - (mem >> 3);
 110         glob->used_memory = 0;
 111         glob->used_total_memory = 0;
 112         glob->shrink = NULL;
 113
 114         mem = si.totalram;
 115         mem *= si.mem_unit;
 116
 117         glob->max_total_memory = mem >> 1;
 118         glob->emer_total_memory = (mem >> 1) + (mem >> 2);
 119
 120         glob->total_memory_swap_limit = glob->max_total_memory - (mem >> 3);
 121
 122         printk(KERN_INFO TTM_PFX "TTM available graphics memory: %llu MiB\n",
 123                glob->max_total_memory >> 20);
 124         printk(KERN_INFO TTM_PFX "TTM available object memory: %llu MiB\n",
 125                glob->max_memory >> 20);
 126
 127         return 0;
 128 }
 129 EXPORT_SYMBOL(ttm_mem_global_init);
 130
 131 void ttm_mem_global_release(struct ttm_mem_global *glob)
 132 {
 133         printk(KERN_INFO TTM_PFX "Used total memory is %llu bytes.\n",
 134                (unsigned long long)glob->used_total_memory);
 135         flush_workqueue(glob->swap_queue);
 136         destroy_workqueue(glob->swap_queue);
 137         glob->swap_queue = NULL;
 138 }
 139 EXPORT_SYMBOL(ttm_mem_global_release);
 140
 141 static inline void ttm_check_swapping(struct ttm_mem_global *glob)
 142 {
 143         bool needs_swapping;
 144
 145         spin_lock(&glob->lock);
 146         needs_swapping = (glob->used_memory > glob->swap_limit ||
 147                           glob->used_total_memory >
 148                           glob->total_memory_swap_limit);
 149         spin_unlock(&glob->lock);
 150
 151         if (unlikely(needs_swapping))
 152                 (void)queue_work(glob->swap_queue, &glob->work);
 153
 154 }
 155
 156 void ttm_mem_global_free(struct ttm_mem_global *glob,
 157                          uint64_t amount, bool himem)
 158 {
 159         spin_lock(&glob->lock);
 160         glob->used_total_memory -= amount;
 161         if (!himem)
 162                 glob->used_memory -= amount;
 163         wake_up_all(&glob->queue);
 164         spin_unlock(&glob->lock);
 165 }
 166
 167 static int ttm_mem_global_reserve(struct ttm_mem_global *glob,
 168                                   uint64_t amount, bool himem, bool reserve)
 169 {
 170         uint64_t limit;
 171         uint64_t lomem_limit;
 172         int ret = -ENOMEM;
 173
 174         spin_lock(&glob->lock);
 175
 176         if (capable(CAP_SYS_ADMIN)) {
 177                 limit = glob->emer_total_memory;
 178                 lomem_limit = glob->emer_memory;
 179         } else {
 180                 limit = glob->max_total_memory;
 181                 lomem_limit = glob->max_memory;
 182         }
 183
 184         if (unlikely(glob->used_total_memory + amount > limit))
 185                 goto out_unlock;
 186         if (unlikely(!himem && glob->used_memory + amount > lomem_limit))
 187                 goto out_unlock;
 188
 189         if (reserve) {
 190                 glob->used_total_memory += amount;
 191                 if (!himem)
 192                         glob->used_memory += amount;
 193         }
 194         ret = 0;
 195 out_unlock:
 196         spin_unlock(&glob->lock);
 197         ttm_check_swapping(glob);
 198
 199         return ret;
 200 }
 201
 202 int ttm_mem_global_alloc(struct ttm_mem_global *glob, uint64_t memory,
 203                          bool no_wait, bool interruptible, bool himem)
 204 {
 205         int count = TTM_MEMORY_ALLOC_RETRIES;
 206
 207         while (unlikely(ttm_mem_global_reserve(glob, memory, himem, true)
 208                         != 0)) {
 209                 if (no_wait)
 210                         return -ENOMEM;
 211                 if (unlikely(count-- == 0))
 212                         return -ENOMEM;
 213                 ttm_shrink(glob, false, memory + (memory >> 2) + 16);
 214         }
 215
 216         return 0;
 217 }
 218
 219 size_t ttm_round_pot(size_t size)
 220 {
 221         if ((size & (size - 1)) == 0)
 222                 return size;
 223         else if (size > PAGE_SIZE)
 224                 return PAGE_ALIGN(size);
 225         else {
 226                 size_t tmp_size = 4;
 227
 228                 while (tmp_size < size)
 229                         tmp_size <<= 1;
 230
 231                 return tmp_size;
 232         }
 233         return 0;
 234 }