summaryrefslogtreecommitdiffstats
path: root/tapset/ioscheduler.stp
blob: d7a71aca29d4477d3287e04162e64ff37171dec3 (plain)
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
// IO scheduler tapset
// Copyright (C) 2005, 2006 IBM Corp.
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.

%{
#include <linux/blkdev.h>
#include <linux/elevator.h>
%}

/**
 * probe ioscheduler.elv_next_request - Retrieve request from request queue
 * @elevator_name: The elevator name
 */
probe ioscheduler.elv_next_request
	=  kernel.function("elv_next_request")
{
%( kernel_v >= "2.6.10" %?
	elevator_name = kernel_string($q->elevator->elevator_type->elevator_name)
%:
	elevator_name = kernel_string($q->elevator->elevator_name)
%)
}

/**
 * probe ioscheduler.elv_next_request.return - Return from retrieving a request
 * @req: Address of the request
 * @req_flags: Request flags
 * @disk_major: Disk major number of the request
 * @disk_minor: Disk minor number of the request
 */
probe ioscheduler.elv_next_request.return
	= kernel.function("elv_next_request").return
{
	if($return == 0)  {
		req = 0
		req_flags = 0
		disk_major = -1
		disk_minor = -1
	} else {
		req = $return
%( kernel_v >= "2.6.19" %?
		req_flags = $return->cmd_flags
%:
		req_flags = $return->flags
%)
		if($return->rq_disk == 0)  {
			disk_major = -1
			disk_minor = -1
		} else {
			disk_major = $return->rq_disk->major
			disk_minor = $return->rq_disk->first_minor
		}
	}
}

/**
 * probe ioscheduler.elv_add_request - Add a request into request queue
 * @elevator_name: The elevator name
 * @req: Address of the request
 * @req_flags: Request flags
 * @disk_major: Disk major number of the request
 * @disk_minor: Disk minor number of the request
 */
/* when a request is added to the request queue */
probe ioscheduler.elv_add_request
	= kernel.function("__elv_add_request")
{
%( kernel_v >= "2.6.10" %?
	elevator_name = kernel_string($q->elevator->elevator_type->elevator_name)
%:
	elevator_name = kernel_string($q->elevator->elevator_name)
%)
	if($rq == 0)  {
		disk_major = -1
		disk_minor = -1
	} else {
		if($rq->rq_disk == 0)  {
			disk_major = -1
			disk_minor = -1
		} else {
			disk_major = $rq->rq_disk->major
			disk_minor = $rq->rq_disk->first_minor
		}
	}

	req = $rq
%( kernel_v >= "2.6.19" %?
	req_flags = $rq==0? 0:$rq->cmd_flags
%:
	req_flags = $rq==0? 0:$rq->flags
%)
}

/**
 * probe ioscheduler.elv_completed_request - Request is completed
 * @elevator_name: The elevator name
 * @req: Address of the request
 * @req_flags: Request flags
 * @disk_major: Disk major number of the request
 * @disk_minor: Disk minor number of the request
 */
probe ioscheduler.elv_completed_request
	= kernel.function("elv_completed_request")
{
%( kernel_v >= "2.6.10" %?
	elevator_name = kernel_string($q->elevator->elevator_type->elevator_name)
%:
	elevator_name = kernel_string($q->elevator->elevator_name)
%)
	if($rq == 0)  {
		disk_major = -1
		disk_minor = -1
	} else {
		if($rq->rq_disk == 0)  {
			disk_major = -1
			disk_minor = -1
		} else {
			disk_major = $rq->rq_disk->major
			disk_minor = $rq->rq_disk->first_minor
		}
	}

	req = $rq
%( kernel_v >= "2.6.19" %?
	req_flags = $rq==0? 0:$rq->cmd_flags
%:
	req_flags = $rq==0? 0:$rq->flags
%)
}

function disk_major_from_request:long(var_q:long)
%{ /* pure */
	struct request_queue *q = (struct request_queue *)((long)THIS->var_q);
	struct list_head *queue_head = &(q->queue_head);

	if (list_empty(&(q->queue_head))) /* FIXME: deref hazard! */
		THIS->__retvalue = -1;
	else  {
		struct request *rq = list_entry_rq(q->queue_head.next); /* FIXME: deref hazard! */
		struct gendisk *rq_disk = kread(&(rq->rq_disk));
		THIS->__retvalue = kread(&(rq_disk->major));
	}
	CATCH_DEREF_FAULT();
%}

function disk_minor_from_request:long(var_q:long)
%{ /* pure */
	struct request_queue *q = (struct request_queue *)((long)THIS->var_q);
	struct list_head *queue_head = &(q->queue_head);

	if (list_empty(&(q->queue_head))) /* FIXME: deref hazard! */
		THIS->__retvalue = -1;
	else  {
		struct request *rq = list_entry_rq(q->queue_head.next); /* FIXME: deref hazard! */
		struct gendisk *rq_disk = kread(&(rq->rq_disk));
		THIS->__retvalue = kread(&(rq_disk->first_minor));
	}
	CATCH_DEREF_FAULT();
%}