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 struct timespec ts;
40
41 ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
42 if (!ctx)
43 goto out;
44 /* Binding to physical processor deferred
45 * until spu_activate().
46 */
47 if (spu_init_csa(&ctx->csa))
48 goto out_free;
49 spin_lock_init(&ctx->mmio_lock);
50 mutex_init(&ctx->mapping_lock);
51 kref_init(&ctx->kref);
52 mutex_init(&ctx->state_mutex);
53 mutex_init(&ctx->run_mutex);
54 init_waitqueue_head(&ctx->ibox_wq);
55 init_waitqueue_head(&ctx->wbox_wq);
56 init_waitqueue_head(&ctx->stop_wq);
57 init_waitqueue_head(&ctx->mfc_wq);
58 init_waitqueue_head(&ctx->run_wq);
59 ctx->state = SPU_STATE_SAVED;
60 ctx->ops = &spu_backing_ops;
61 ctx->owner = get_task_mm(current);
62 INIT_LIST_HEAD(&ctx->rq);
63 INIT_LIST_HEAD(&ctx->aff_list);
64 if (gang)
65 spu_gang_add_ctx(gang, ctx);
66
67 __spu_update_sched_info(ctx);
68 spu_set_timeslice(ctx);
69 ctx->stats.util_state = SPU_UTIL_IDLE_LOADED;
70 ktime_get_ts(&ts);
71 ctx->stats.tstamp = timespec_to_ns(&ts);
72
73 atomic_inc(&nr_spu_contexts);
74 goto out;
75 out_free:
76 kfree(ctx);
77 ctx = NULL;
78 out:
79 return ctx;
80 }
81
destroy_spu_context(struct kref * kref)82 void destroy_spu_context(struct kref *kref)
83 {
84 struct spu_context *ctx;
85 ctx = container_of(kref, struct spu_context, kref);
86 spu_context_nospu_trace(destroy_spu_context__enter, ctx);
87 mutex_lock(&ctx->state_mutex);
88 spu_deactivate(ctx);
89 mutex_unlock(&ctx->state_mutex);
90 spu_fini_csa(&ctx->csa);
91 if (ctx->gang)
92 spu_gang_remove_ctx(ctx->gang, ctx);
93 if (ctx->prof_priv_kref)
94 kref_put(ctx->prof_priv_kref, ctx->prof_priv_release);
95 BUG_ON(!list_empty(&ctx->rq));
96 atomic_dec(&nr_spu_contexts);
97 kfree(ctx->switch_log);
98 kfree(ctx);
99 }
100
get_spu_context(struct spu_context * ctx)101 struct spu_context * get_spu_context(struct spu_context *ctx)
102 {
103 kref_get(&ctx->kref);
104 return ctx;
105 }
106
put_spu_context(struct spu_context * ctx)107 int put_spu_context(struct spu_context *ctx)
108 {
109 return kref_put(&ctx->kref, &destroy_spu_context);
110 }
111
112 /* give up the mm reference when the context is about to be destroyed */
spu_forget(struct spu_context * ctx)113 void spu_forget(struct spu_context *ctx)
114 {
115 struct mm_struct *mm;
116
117 /*
118 * This is basically an open-coded spu_acquire_saved, except that
119 * we don't acquire the state mutex interruptible, and we don't
120 * want this context to be rescheduled on release.
121 */
122 mutex_lock(&ctx->state_mutex);
123 if (ctx->state != SPU_STATE_SAVED)
124 spu_deactivate(ctx);
125
126 mm = ctx->owner;
127 ctx->owner = NULL;
128 mmput(mm);
129 spu_release(ctx);
130 }
131
spu_unmap_mappings(struct spu_context * ctx)132 void spu_unmap_mappings(struct spu_context *ctx)
133 {
134 mutex_lock(&ctx->mapping_lock);
135 if (ctx->local_store)
136 unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
137 if (ctx->mfc)
138 unmap_mapping_range(ctx->mfc, 0, SPUFS_MFC_MAP_SIZE, 1);
139 if (ctx->cntl)
140 unmap_mapping_range(ctx->cntl, 0, SPUFS_CNTL_MAP_SIZE, 1);
141 if (ctx->signal1)
142 unmap_mapping_range(ctx->signal1, 0, SPUFS_SIGNAL_MAP_SIZE, 1);
143 if (ctx->signal2)
144 unmap_mapping_range(ctx->signal2, 0, SPUFS_SIGNAL_MAP_SIZE, 1);
145 if (ctx->mss)
146 unmap_mapping_range(ctx->mss, 0, SPUFS_MSS_MAP_SIZE, 1);
147 if (ctx->psmap)
148 unmap_mapping_range(ctx->psmap, 0, SPUFS_PS_MAP_SIZE, 1);
149 mutex_unlock(&ctx->mapping_lock);
150 }
151
152 /**
153 * spu_acquire_saved - lock spu contex and make sure it is in saved state
154 * @ctx: spu contex to lock
155 */
spu_acquire_saved(struct spu_context * ctx)156 int spu_acquire_saved(struct spu_context *ctx)
157 {
158 int ret;
159
160 spu_context_nospu_trace(spu_acquire_saved__enter, ctx);
161
162 ret = spu_acquire(ctx);
163 if (ret)
164 return ret;
165
166 if (ctx->state != SPU_STATE_SAVED) {
167 set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
168 spu_deactivate(ctx);
169 }
170
171 return 0;
172 }
173
174 /**
175 * spu_release_saved - unlock spu context and return it to the runqueue
176 * @ctx: context to unlock
177 */
spu_release_saved(struct spu_context * ctx)178 void spu_release_saved(struct spu_context *ctx)
179 {
180 BUG_ON(ctx->state != SPU_STATE_SAVED);
181
182 if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags) &&
183 test_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags))
184 spu_activate(ctx, 0);
185
186 spu_release(ctx);
187 }
188
189