2 * Memory mapped I/O tracing
4 * Copyright (C) 2008 Pekka Paalanen <pq@iki.fi>
9 #include <linux/kernel.h>
10 #include <linux/mmiotrace.h>
11 #include <linux/pci.h>
19 static struct trace_array
*mmio_trace_array
;
20 static bool overrun_detected
;
22 static void mmio_reset_data(struct trace_array
*tr
)
26 overrun_detected
= false;
27 tr
->time_start
= ftrace_now(tr
->cpu
);
29 for_each_online_cpu(cpu
)
30 tracing_reset(tr
, cpu
);
33 static void mmio_trace_init(struct trace_array
*tr
)
35 pr_debug("in %s\n", __func__
);
36 mmio_trace_array
= tr
;
42 static void mmio_trace_reset(struct trace_array
*tr
)
44 pr_debug("in %s\n", __func__
);
48 mmio_trace_array
= NULL
;
51 static void mmio_trace_start(struct trace_array
*tr
)
53 pr_debug("in %s\n", __func__
);
57 static int mmio_print_pcidev(struct trace_seq
*s
, const struct pci_dev
*dev
)
61 resource_size_t start
, end
;
62 const struct pci_driver
*drv
= pci_dev_driver(dev
);
64 /* XXX: incomplete checks for trace_seq_printf() return value */
65 ret
+= trace_seq_printf(s
, "PCIDEV %02x%02x %04x%04x %x",
66 dev
->bus
->number
, dev
->devfn
,
67 dev
->vendor
, dev
->device
, dev
->irq
);
69 * XXX: is pci_resource_to_user() appropriate, since we are
70 * supposed to interpret the __ioremap() phys_addr argument based on
71 * these printed values?
73 for (i
= 0; i
< 7; i
++) {
74 pci_resource_to_user(dev
, i
, &dev
->resource
[i
], &start
, &end
);
75 ret
+= trace_seq_printf(s
, " %llx",
76 (unsigned long long)(start
|
77 (dev
->resource
[i
].flags
& PCI_REGION_FLAG_MASK
)));
79 for (i
= 0; i
< 7; i
++) {
80 pci_resource_to_user(dev
, i
, &dev
->resource
[i
], &start
, &end
);
81 ret
+= trace_seq_printf(s
, " %llx",
82 dev
->resource
[i
].start
< dev
->resource
[i
].end
?
83 (unsigned long long)(end
- start
) + 1 : 0);
86 ret
+= trace_seq_printf(s
, " %s\n", drv
->name
);
88 ret
+= trace_seq_printf(s
, " \n");
92 static void destroy_header_iter(struct header_iter
*hiter
)
96 pci_dev_put(hiter
->dev
);
100 static void mmio_pipe_open(struct trace_iterator
*iter
)
102 struct header_iter
*hiter
;
103 struct trace_seq
*s
= &iter
->seq
;
105 trace_seq_printf(s
, "VERSION 20070824\n");
107 hiter
= kzalloc(sizeof(*hiter
), GFP_KERNEL
);
111 hiter
->dev
= pci_get_device(PCI_ANY_ID
, PCI_ANY_ID
, NULL
);
112 iter
->private = hiter
;
115 /* XXX: This is not called when the pipe is closed! */
116 static void mmio_close(struct trace_iterator
*iter
)
118 struct header_iter
*hiter
= iter
->private;
119 destroy_header_iter(hiter
);
120 iter
->private = NULL
;
123 static unsigned long count_overruns(struct trace_iterator
*iter
)
126 unsigned long cnt
= 0;
129 for_each_online_cpu(cpu
) {
130 cnt
+= iter
->overrun
[cpu
];
131 iter
->overrun
[cpu
] = 0;
138 static ssize_t
mmio_read(struct trace_iterator
*iter
, struct file
*filp
,
139 char __user
*ubuf
, size_t cnt
, loff_t
*ppos
)
142 struct header_iter
*hiter
= iter
->private;
143 struct trace_seq
*s
= &iter
->seq
;
146 n
= count_overruns(iter
);
148 /* XXX: This is later than where events were lost. */
149 trace_seq_printf(s
, "MARK 0.000000 Lost %lu events.\n", n
);
150 if (!overrun_detected
)
151 pr_warning("mmiotrace has lost events.\n");
152 overrun_detected
= true;
159 mmio_print_pcidev(s
, hiter
->dev
);
160 hiter
->dev
= pci_get_device(PCI_ANY_ID
, PCI_ANY_ID
, hiter
->dev
);
163 destroy_header_iter(hiter
);
164 iter
->private = NULL
;
168 ret
= trace_seq_to_user(s
, ubuf
, cnt
);
169 return (ret
== -EBUSY
) ? 0 : ret
;
172 static enum print_line_t
mmio_print_rw(struct trace_iterator
*iter
)
174 struct trace_entry
*entry
= iter
->ent
;
175 struct trace_mmiotrace_rw
*field
;
176 struct mmiotrace_rw
*rw
;
177 struct trace_seq
*s
= &iter
->seq
;
178 unsigned long long t
= ns2usecs(iter
->ts
);
179 unsigned long usec_rem
= do_div(t
, 1000000ULL);
180 unsigned secs
= (unsigned long)t
;
183 trace_assign_type(field
, entry
);
186 switch (rw
->opcode
) {
188 ret
= trace_seq_printf(s
,
189 "R %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
190 rw
->width
, secs
, usec_rem
, rw
->map_id
,
191 (unsigned long long)rw
->phys
,
192 rw
->value
, rw
->pc
, 0);
195 ret
= trace_seq_printf(s
,
196 "W %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
197 rw
->width
, secs
, usec_rem
, rw
->map_id
,
198 (unsigned long long)rw
->phys
,
199 rw
->value
, rw
->pc
, 0);
201 case MMIO_UNKNOWN_OP
:
202 ret
= trace_seq_printf(s
,
203 "UNKNOWN %lu.%06lu %d 0x%llx %02x,%02x,%02x 0x%lx %d\n",
204 secs
, usec_rem
, rw
->map_id
,
205 (unsigned long long)rw
->phys
,
206 (rw
->value
>> 16) & 0xff, (rw
->value
>> 8) & 0xff,
207 (rw
->value
>> 0) & 0xff, rw
->pc
, 0);
210 ret
= trace_seq_printf(s
, "rw what?\n");
214 return TRACE_TYPE_HANDLED
;
215 return TRACE_TYPE_PARTIAL_LINE
;
218 static enum print_line_t
mmio_print_map(struct trace_iterator
*iter
)
220 struct trace_entry
*entry
= iter
->ent
;
221 struct trace_mmiotrace_map
*field
;
222 struct mmiotrace_map
*m
;
223 struct trace_seq
*s
= &iter
->seq
;
224 unsigned long long t
= ns2usecs(iter
->ts
);
225 unsigned long usec_rem
= do_div(t
, 1000000ULL);
226 unsigned secs
= (unsigned long)t
;
229 trace_assign_type(field
, entry
);
234 ret
= trace_seq_printf(s
,
235 "MAP %lu.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
236 secs
, usec_rem
, m
->map_id
,
237 (unsigned long long)m
->phys
, m
->virt
, m
->len
,
241 ret
= trace_seq_printf(s
,
242 "UNMAP %lu.%06lu %d 0x%lx %d\n",
243 secs
, usec_rem
, m
->map_id
, 0UL, 0);
246 ret
= trace_seq_printf(s
, "map what?\n");
250 return TRACE_TYPE_HANDLED
;
251 return TRACE_TYPE_PARTIAL_LINE
;
254 static enum print_line_t
mmio_print_mark(struct trace_iterator
*iter
)
256 struct trace_entry
*entry
= iter
->ent
;
257 struct print_entry
*print
= (struct print_entry
*)entry
;
258 const char *msg
= print
->buf
;
259 struct trace_seq
*s
= &iter
->seq
;
260 unsigned long long t
= ns2usecs(iter
->ts
);
261 unsigned long usec_rem
= do_div(t
, 1000000ULL);
262 unsigned secs
= (unsigned long)t
;
265 /* The trailing newline must be in the message. */
266 ret
= trace_seq_printf(s
, "MARK %lu.%06lu %s", secs
, usec_rem
, msg
);
268 return TRACE_TYPE_PARTIAL_LINE
;
270 if (entry
->flags
& TRACE_FLAG_CONT
)
271 trace_seq_print_cont(s
, iter
);
273 return TRACE_TYPE_HANDLED
;
276 static enum print_line_t
mmio_print_line(struct trace_iterator
*iter
)
278 switch (iter
->ent
->type
) {
280 return mmio_print_rw(iter
);
282 return mmio_print_map(iter
);
284 return mmio_print_mark(iter
);
286 return TRACE_TYPE_HANDLED
; /* ignore unknown entries */
290 static struct tracer mmio_tracer __read_mostly
=
293 .init
= mmio_trace_init
,
294 .reset
= mmio_trace_reset
,
295 .start
= mmio_trace_start
,
296 .pipe_open
= mmio_pipe_open
,
299 .print_line
= mmio_print_line
,
302 __init
static int init_mmio_trace(void)
304 return register_tracer(&mmio_tracer
);
306 device_initcall(init_mmio_trace
);
308 static void __trace_mmiotrace_rw(struct trace_array
*tr
,
309 struct trace_array_cpu
*data
,
310 struct mmiotrace_rw
*rw
)
312 struct ring_buffer_event
*event
;
313 struct trace_mmiotrace_rw
*entry
;
314 unsigned long irq_flags
;
316 event
= ring_buffer_lock_reserve(tr
->buffer
, sizeof(*entry
),
320 entry
= ring_buffer_event_data(event
);
321 tracing_generic_entry_update(&entry
->ent
, 0, preempt_count());
322 entry
->ent
.type
= TRACE_MMIO_RW
;
324 ring_buffer_unlock_commit(tr
->buffer
, event
, irq_flags
);
329 void mmio_trace_rw(struct mmiotrace_rw
*rw
)
331 struct trace_array
*tr
= mmio_trace_array
;
332 struct trace_array_cpu
*data
= tr
->data
[smp_processor_id()];
333 __trace_mmiotrace_rw(tr
, data
, rw
);
336 static void __trace_mmiotrace_map(struct trace_array
*tr
,
337 struct trace_array_cpu
*data
,
338 struct mmiotrace_map
*map
)
340 struct ring_buffer_event
*event
;
341 struct trace_mmiotrace_map
*entry
;
342 unsigned long irq_flags
;
344 event
= ring_buffer_lock_reserve(tr
->buffer
, sizeof(*entry
),
348 entry
= ring_buffer_event_data(event
);
349 tracing_generic_entry_update(&entry
->ent
, 0, preempt_count());
350 entry
->ent
.type
= TRACE_MMIO_MAP
;
352 ring_buffer_unlock_commit(tr
->buffer
, event
, irq_flags
);
357 void mmio_trace_mapping(struct mmiotrace_map
*map
)
359 struct trace_array
*tr
= mmio_trace_array
;
360 struct trace_array_cpu
*data
;
363 data
= tr
->data
[smp_processor_id()];
364 __trace_mmiotrace_map(tr
, data
, map
);
368 int mmio_trace_printk(const char *fmt
, va_list args
)
370 return trace_vprintk(0, fmt
, args
);