kernel/2.6.29.6-aldebaran-rt/arch/powerpc/platforms/cell/spufs/gang.c

   1 /*
   2  * SPU file system
   3  *
   4  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
   5  *
   6  * Author: Arnd Bergmann <arndb@de.ibm.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #include <linux/list.h>
  24 #include <linux/slab.h>
  25
  26 #include "spufs.h"
  27
  28 struct spu_gang *alloc_spu_gang(void)
  29 {
  30         struct spu_gang *gang;
  31
  32         gang = kzalloc(sizeof *gang, GFP_KERNEL);
  33         if (!gang)
  34                 goto out;
  35
  36         kref_init(&gang->kref);
  37         mutex_init(&gang->mutex);
  38         mutex_init(&gang->aff_mutex);
  39         INIT_LIST_HEAD(&gang->list);
  40         INIT_LIST_HEAD(&gang->aff_list_head);
  41
  42 out:
  43         return gang;
  44 }
  45
  46 static void destroy_spu_gang(struct kref *kref)
  47 {
  48         struct spu_gang *gang;
  49         gang = container_of(kref, struct spu_gang, kref);
  50         WARN_ON(gang->contexts || !list_empty(&gang->list));
  51         kfree(gang);
  52 }
  53
  54 struct spu_gang *get_spu_gang(struct spu_gang *gang)
  55 {
  56         kref_get(&gang->kref);
  57         return gang;
  58 }
  59
  60 int put_spu_gang(struct spu_gang *gang)
  61 {
  62         return kref_put(&gang->kref, &destroy_spu_gang);
  63 }
  64
  65 void spu_gang_add_ctx(struct spu_gang *gang, struct spu_context *ctx)
  66 {
  67         mutex_lock(&gang->mutex);
  68         ctx->gang = get_spu_gang(gang);
  69         list_add(&ctx->gang_list, &gang->list);
  70         gang->contexts++;
  71         mutex_unlock(&gang->mutex);
  72 }
  73
  74 void spu_gang_remove_ctx(struct spu_gang *gang, struct spu_context *ctx)
  75 {
  76         mutex_lock(&gang->mutex);
  77         WARN_ON(ctx->gang != gang);
  78         if (!list_empty(&ctx->aff_list)) {
  79                 list_del_init(&ctx->aff_list);
  80                 gang->aff_flags &= ~AFF_OFFSETS_SET;
  81         }
  82         list_del_init(&ctx->gang_list);
  83         gang->contexts--;
  84         mutex_unlock(&gang->mutex);
  85
  86         put_spu_gang(gang);
  87 }