1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
|
From 2bb424e80da086b42ea6f6f00a8a7ab1b2fd63d1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6nig?= <christian.koenig@amd.com>
Date: Tue, 5 Jun 2018 11:47:43 +0200
Subject: [PATCH 4618/5725] drm/amdgpu: fix documentation of amdgpu_mn.c v2
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
And wire it up as well.
v2: improve the wording, fix label mismatch
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 74 ++++++++++++++++++++++++++--------
1 file changed, 58 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
index 211539f..7aaef93 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
@@ -28,6 +28,21 @@
* Christian König <christian.koenig@amd.com>
*/
+/**
+ * DOC: MMU Notifier
+ *
+ * For coherent userptr handling registers an MMU notifier to inform the driver
+ * about updates on the page tables of a process.
+ *
+ * When somebody tries to invalidate the page tables we block the update until
+ * all operations on the pages in question are completed, then those pages are
+ * marked as accessed and also dirty if it wasn't a read only access.
+ *
+ * New command submissions using the userptrs in question are delayed until all
+ * page table invalidation are completed and we once more see a coherent process
+ * address space.
+ */
+
#include <linux/firmware.h>
#include <linux/module.h>
#include <linux/mmu_notifier.h>
@@ -38,6 +53,21 @@
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"
+/**
+ * struct amdgpu_mn
+ *
+ * @adev: amdgpu device pointer
+ * @mm: process address space
+ * @mn: MMU notifier structur
+ * @work: destrution work item
+ * @node: hash table node to find structure by adev and mn
+ * @lock: rw semaphore protecting the notifier nodes
+ * @objects: interval tree containing amdgpu_mn_nodes
+ * @read_lock: mutex for recursive locking of @lock
+ * @recursion: depth of recursion
+ *
+ * Data for each amdgpu device and process address space.
+ */
struct amdgpu_mn {
/* constant after initialisation */
struct amdgpu_device *adev;
@@ -62,13 +92,21 @@ struct amdgpu_mn {
atomic_t recursion;
};
+/**
+ * struct amdgpu_mn_node
+ *
+ * @it: interval node defining start-last of the affected address range
+ * @bos: list of all BOs in the affected address range
+ *
+ * Manages all BOs which are affected of a certain range of address space.
+ */
struct amdgpu_mn_node {
struct interval_tree_node it;
struct list_head bos;
};
/**
- * amdgpu_mn_destroy - destroy the amn
+ * amdgpu_mn_destroy - destroy the MMU notifier
*
* @work: previously sheduled work item
*
@@ -106,7 +144,7 @@ static void amdgpu_mn_destroy(struct work_struct *work)
* amdgpu_mn_release - callback to notify about mm destruction
*
* @mn: our notifier
- * @mn: the mm this callback is about
+ * @mm: the mm this callback is about
*
* Shedule a work item to lazy destroy our notifier.
*/
@@ -114,13 +152,16 @@ static void amdgpu_mn_release(struct mmu_notifier *mn,
struct mm_struct *mm)
{
struct amdgpu_mn *amn = container_of(mn, struct amdgpu_mn, mn);
+
INIT_WORK(&amn->work, amdgpu_mn_destroy);
schedule_work(&amn->work);
}
/**
- * amdgpu_mn_lock - take the write side lock for this mn
+ * amdgpu_mn_lock - take the write side lock for this notifier
+ *
+ * @mn: our notifier
*/
void amdgpu_mn_lock(struct amdgpu_mn *mn)
{
@@ -129,7 +170,9 @@ void amdgpu_mn_lock(struct amdgpu_mn *mn)
}
/**
- * amdgpu_mn_unlock - drop the write side lock for this mn
+ * amdgpu_mn_unlock - drop the write side lock for this notifier
+ *
+ * @mn: our notifier
*/
void amdgpu_mn_unlock(struct amdgpu_mn *mn)
{
@@ -138,11 +181,9 @@ void amdgpu_mn_unlock(struct amdgpu_mn *mn)
}
/**
- * amdgpu_mn_read_lock - take the amn read lock
+ * amdgpu_mn_read_lock - take the read side lock for this notifier
*
* @amn: our notifier
- *
- * Take the amn read side lock.
*/
static void amdgpu_mn_read_lock(struct amdgpu_mn *amn)
{
@@ -153,11 +194,9 @@ static void amdgpu_mn_read_lock(struct amdgpu_mn *amn)
}
/**
- * amdgpu_mn_read_unlock - drop the amn read lock
+ * amdgpu_mn_read_unlock - drop the read side lock for this notifier
*
* @amn: our notifier
- *
- * Drop the amn read side lock.
*/
static void amdgpu_mn_read_unlock(struct amdgpu_mn *amn)
{
@@ -169,9 +208,11 @@ static void amdgpu_mn_read_unlock(struct amdgpu_mn *amn)
* amdgpu_mn_invalidate_node - unmap all BOs of a node
*
* @node: the node with the BOs to unmap
+ * @start: start of address range affected
+ * @end: end of address range affected
*
- * We block for all BOs and unmap them by move them
- * into system domain again.
+ * Block for operations on BOs to finish and mark pages as accessed and
+ * potentially dirty.
*/
static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
unsigned long start,
@@ -198,12 +239,12 @@ static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
* amdgpu_mn_invalidate_range_start_gfx - callback to notify about mm change
*
* @mn: our notifier
- * @mn: the mm this callback is about
+ * @mm: the mm this callback is about
* @start: start of updated range
* @end: end of updated range
*
- * We block for all BOs between start and end to be idle and
- * unmap them by move them into system domain again.
+ * Block for operations on BOs to finish and mark pages as accessed and
+ * potentially dirty.
*/
static void amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn,
struct mm_struct *mm,
@@ -233,7 +274,7 @@ static void amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn,
* amdgpu_mn_invalidate_range_end_gfx - callback to notify about mm change
*
* @mn: our notifier
- * @mn: the mm this callback is about
+ * @mm: the mm this callback is about
* @start: start of updated range
* @end: end of updated range
*
@@ -488,6 +529,7 @@ void amdgpu_mn_unregister(struct amdgpu_bo *bo)
if (list_empty(head)) {
struct amdgpu_mn_node *node;
+
node = container_of(head, struct amdgpu_mn_node, bos);
interval_tree_remove(&node->it, &amn->objects);
kfree(node);
--
2.7.4
|
