1 /*
2 * SPU file system -- SPU context management
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/fs.h>
24 #include <linux/mm.h>
25 #include <linux/slab.h>
26 #include <linux/atomic.h>
27 #include <linux/sched.h>
28 #include <asm/spu.h>
29 #include <asm/spu_csa.h>
30 #include "spufs.h"
31 #include "sputrace.h"
32
33
34 atomic_t nr_spu_contexts = ATOMIC_INIT(0);
35
alloc_spu_context(struct spu_gang * gang)36 struct spu_context *alloc_spu_context(struct spu_gang *gang)
37 {
38 struct spu_context *ctx;
39
40 ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
41 if (!ctx)
42 goto out;
43 /* Binding to physical processor deferred
44 * until spu_activate().
45 */
46 if (spu_init_csa(&ctx->csa))
47 goto out_free;
48 spin_lock_init(&ctx->mmio_lock);
49 mutex_init(&ctx->mapping_lock);
50 kref_init(&ctx->kref);
51 mutex_init(&ctx->state_mutex);
52 mutex_init(&ctx->run_mutex);
53 init_waitqueue_head(&ctx->ibox_wq);
54 init_waitqueue_head(&ctx->wbox_wq);
55 init_waitqueue_head(&ctx->stop_wq);
56 init_waitqueue_head(&ctx->mfc_wq);
57 init_waitqueue_head(&ctx->run_wq);
58 ctx->state = SPU_STATE_SAVED;
59 ctx->ops = &spu_backing_ops;
60 ctx->owner = get_task_mm(current);
61 INIT_LIST_HEAD(&ctx->rq);
62 INIT_LIST_HEAD(&ctx->aff_list);
63 if (gang)
64 spu_gang_add_ctx(gang, ctx);
65
66 __spu_update_sched_info(ctx);
67 spu_set_timeslice(ctx);
68 ctx->stats.util_state = SPU_UTIL_IDLE_LOADED;
69 ctx->stats.tstamp = ktime_get_ns();
70
71 atomic_inc(&nr_spu_contexts);
72 goto out;
73 out_free:
74 kfree(ctx);
75 ctx = NULL;
76 out:
77 return ctx;
78 }
79
destroy_spu_context(struct kref * kref)80 void destroy_spu_context(struct kref *kref)
81 {
82 struct spu_context *ctx;
83 ctx = container_of(kref, struct spu_context, kref);
84 spu_context_nospu_trace(destroy_spu_context__enter, ctx);
85 mutex_lock(&ctx->state_mutex);
86 spu_deactivate(ctx);
87 mutex_unlock(&ctx->state_mutex);
88 spu_fini_csa(&ctx->csa);
89 if (ctx->gang)
90 spu_gang_remove_ctx(ctx->gang, ctx);
91 if (ctx->prof_priv_kref)
92 kref_put(ctx->prof_priv_kref, ctx->prof_priv_release);
93 BUG_ON(!list_empty(&ctx->rq));
94 atomic_dec(&nr_spu_contexts);
95 kfree(ctx->switch_log);
96 kfree(ctx);
97 }
98
get_spu_context(struct spu_context * ctx)99 struct spu_context * get_spu_context(struct spu_context *ctx)
100 {
101 kref_get(&ctx->kref);
102 return ctx;
103 }
104
put_spu_context(struct spu_context * ctx)105 int put_spu_context(struct spu_context *ctx)
106 {
107 return kref_put(&ctx->kref, &destroy_spu_context);
108 }
109
110 /* give up the mm reference when the context is about to be destroyed */
spu_forget(struct spu_context * ctx)111 void spu_forget(struct spu_context *ctx)
112 {
113 struct mm_struct *mm;
114
115 /*
116 * This is basically an open-coded spu_acquire_saved, except that
117 * we don't acquire the state mutex interruptible, and we don't
118 * want this context to be rescheduled on release.
119 */
120 mutex_lock(&ctx->state_mutex);
121 if (ctx->state != SPU_STATE_SAVED)
122 spu_deactivate(ctx);
123
124 mm = ctx->owner;
125 ctx->owner = NULL;
126 mmput(mm);
127 spu_release(ctx);
128 }
129
spu_unmap_mappings(struct spu_context * ctx)130 void spu_unmap_mappings(struct spu_context *ctx)
131 {
132 mutex_lock(&ctx->mapping_lock);
133 if (ctx->local_store)
134 unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
135 if (ctx->mfc)
136 unmap_mapping_range(ctx->mfc, 0, SPUFS_MFC_MAP_SIZE, 1);
137 if (ctx->cntl)
138 unmap_mapping_range(ctx->cntl, 0, SPUFS_CNTL_MAP_SIZE, 1);
139 if (ctx->signal1)
140 unmap_mapping_range(ctx->signal1, 0, SPUFS_SIGNAL_MAP_SIZE, 1);
141 if (ctx->signal2)
142 unmap_mapping_range(ctx->signal2, 0, SPUFS_SIGNAL_MAP_SIZE, 1);
143 if (ctx->mss)
144 unmap_mapping_range(ctx->mss, 0, SPUFS_MSS_MAP_SIZE, 1);
145 if (ctx->psmap)
146 unmap_mapping_range(ctx->psmap, 0, SPUFS_PS_MAP_SIZE, 1);
147 mutex_unlock(&ctx->mapping_lock);
148 }
149
150 /**
151 * spu_acquire_saved - lock spu contex and make sure it is in saved state
152 * @ctx: spu contex to lock
153 */
spu_acquire_saved(struct spu_context * ctx)154 int spu_acquire_saved(struct spu_context *ctx)
155 {
156 int ret;
157
158 spu_context_nospu_trace(spu_acquire_saved__enter, ctx);
159
160 ret = spu_acquire(ctx);
161 if (ret)
162 return ret;
163
164 if (ctx->state != SPU_STATE_SAVED) {
165 set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
166 spu_deactivate(ctx);
167 }
168
169 return 0;
170 }
171
172 /**
173 * spu_release_saved - unlock spu context and return it to the runqueue
174 * @ctx: context to unlock
175 */
spu_release_saved(struct spu_context * ctx)176 void spu_release_saved(struct spu_context *ctx)
177 {
178 BUG_ON(ctx->state != SPU_STATE_SAVED);
179
180 if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags) &&
181 test_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags))
182 spu_activate(ctx, 0);
183
184 spu_release(ctx);
185 }
186
187