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1 /*
2  * Copyright (c) 2013 Ben Noordhuis <info@bnoordhuis.nl>
3  * Copyright (c) 2013-2015 Dmitry V. Levin <ldv@altlinux.org>
4  * Copyright (c) 2016 Eugene Syromyatnikov <evgsyr@gmail.com>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include "defs.h"
31 
32 #include "perf_event_struct.h"
33 
34 #include "xlat/clocknames.h"
35 #include "xlat/hw_breakpoint_len.h"
36 #include "xlat/hw_breakpoint_type.h"
37 #include "xlat/perf_attr_size.h"
38 #include "xlat/perf_branch_sample_type.h"
39 #include "xlat/perf_event_open_flags.h"
40 #include "xlat/perf_event_read_format.h"
41 #include "xlat/perf_event_sample_format.h"
42 #include "xlat/perf_hw_cache_id.h"
43 #include "xlat/perf_hw_cache_op_id.h"
44 #include "xlat/perf_hw_cache_op_result_id.h"
45 #include "xlat/perf_hw_id.h"
46 #include "xlat/perf_sw_ids.h"
47 #include "xlat/perf_type_id.h"
48 
49 struct pea_desc {
50 	struct perf_event_attr *attr;
51 	uint32_t size;
52 };
53 
54 static void
free_pea_desc(void * pea_desc_ptr)55 free_pea_desc(void *pea_desc_ptr)
56 {
57 	struct pea_desc *desc = pea_desc_ptr;
58 
59 	free(desc->attr);
60 	free(desc);
61 }
62 
63 static int
fetch_perf_event_attr(struct tcb * const tcp,const kernel_ulong_t addr)64 fetch_perf_event_attr(struct tcb *const tcp, const kernel_ulong_t addr)
65 {
66 	struct pea_desc *desc;
67 	struct perf_event_attr *attr;
68 	uint32_t size;
69 
70 	if (umove(tcp, addr + offsetof(struct perf_event_attr, size), &size)) {
71 		printaddr(addr);
72 		return 1;
73 	}
74 
75 	if (size > sizeof(*attr))
76 		size = sizeof(*attr);
77 
78 	if (!size)
79 		size = PERF_ATTR_SIZE_VER0;
80 
81 	/*
82 	 * Kernel (rightfully) deems invalid attribute structures with size less
83 	 * than first published format size, and we do the same.
84 	 */
85 	if (size < PERF_ATTR_SIZE_VER0) {
86 		printaddr(addr);
87 		return 1;
88 	}
89 
90 	if (abbrev(tcp))
91 		size = offsetofend(struct perf_event_attr, config);
92 
93 	/* Size should be multiple of 8, but kernel doesn't check for it */
94 	/* size &= ~7; */
95 
96 	attr = xcalloc(1, sizeof(*attr));
97 
98 	if (umoven_or_printaddr(tcp, addr, size, attr)) {
99 		free(attr);
100 
101 		return 1;
102 	}
103 
104 	desc = xmalloc(sizeof(*desc));
105 
106 	desc->attr = attr;
107 	desc->size = size;
108 
109 	set_tcb_priv_data(tcp, desc, free_pea_desc);
110 
111 	return 0;
112 }
113 
114 #define PRINT_XLAT(prefix, xlat, x, dflt) \
115 	do { \
116 		tprints(prefix); \
117 		printxval_search(xlat, x, dflt); \
118 	} while (0)
119 
120 static void
print_perf_event_attr(struct tcb * const tcp,const kernel_ulong_t addr)121 print_perf_event_attr(struct tcb *const tcp, const kernel_ulong_t addr)
122 {
123 	static const char *precise_ip_desc[] = {
124 		"arbitrary skid",
125 		"constant skid",
126 		"requested to have 0 skid",
127 		"must have 0 skid",
128 	};
129 
130 	struct pea_desc *desc;
131 	struct perf_event_attr *attr;
132 	uint32_t size;
133 	uint32_t new_size;
134 	int use_new_size = 0;
135 
136 	/*
137 	 * Amusingly, kernel accepts structures with only part of the field
138 	 * present, so we making check like this (instead of checking
139 	 * offsetofend against size) in order to print fields as kernel sees
140 	 * them. This also should work great on big endian architectures.
141 	 */
142 	#define _PERF_CHECK_FIELD(_field) \
143 		do { \
144 			if (offsetof(struct perf_event_attr, _field) >= size) \
145 				goto print_perf_event_attr_out; \
146 		} while (0)
147 
148 	desc = get_tcb_priv_data(tcp);
149 
150 	attr = desc->attr;
151 	size = desc->size;
152 
153 	/* The only error which expected to change size field currently */
154 	if (tcp->u_error == E2BIG) {
155 		if (umove(tcp, addr + offsetof(struct perf_event_attr, size),
156 		    &new_size))
157 			use_new_size = -1;
158 		else
159 			use_new_size = 1;
160 	}
161 
162 	PRINT_XLAT("{type=", perf_type_id, attr->type, "PERF_TYPE_???");
163 	tprintf(", size=");
164 	printxval(perf_attr_size, attr->size, "PERF_ATTR_SIZE_???");
165 
166 	if (use_new_size) {
167 		tprints(" => ");
168 
169 		if (use_new_size > 0)
170 			printxval(perf_attr_size, new_size,
171 			          "PERF_ATTR_SIZE_???");
172 		else
173 			tprints("???");
174 	}
175 
176 	switch (attr->type) {
177 	case PERF_TYPE_HARDWARE:
178 		PRINT_XLAT(", config=", perf_hw_id, attr->config,
179 		           "PERF_COUNT_HW_???");
180 		break;
181 	case PERF_TYPE_SOFTWARE:
182 		PRINT_XLAT(", config=", perf_sw_ids, attr->config,
183 		           "PERF_COUNT_SW_???");
184 		break;
185 	case PERF_TYPE_TRACEPOINT:
186 		/*
187 		 * "The value to use in config can be obtained from under
188 		 * debugfs tracing/events/../../id if ftrace is enabled in the
189                  * kernel."
190 		 */
191 		tprintf(", config=%" PRIu64, attr->config);
192 		break;
193 	case PERF_TYPE_HW_CACHE:
194 		/*
195 		 * (perf_hw_cache_id) | (perf_hw_cache_op_id << 8) |
196 		 * (perf_hw_cache_op_result_id << 16)
197 		 */
198 		PRINT_XLAT(", config=", perf_hw_cache_id, attr->config & 0xFF,
199 		           "PERF_COUNT_HW_CACHE_???");
200 		PRINT_XLAT("|", perf_hw_cache_op_id, (attr->config >> 8) & 0xFF,
201 		           "PERF_COUNT_HW_CACHE_OP_???");
202 		/*
203 		 * Current code (see set_ext_hw_attr in arch/x86/events/core.c,
204 		 * tile_map_cache_event in arch/tile/kernel/perf_event.c,
205 		 * arc_pmu_cache_event in arch/arc/kernel/perf_event.c,
206 		 * hw_perf_cache_event in arch/blackfin/kernel/perf_event.c,
207 		 * _hw_perf_cache_event in arch/metag/kernel/perf/perf_event.c,
208 		 * mipspmu_map_cache_event in arch/mips/kernel/perf_event_mipsxx.c,
209 		 * hw_perf_cache_event in arch/powerpc/perf/core-book3s.c,
210 		 * hw_perf_cache_event in arch/powerpc/perf/core-fsl-emb.c,
211 		 * hw_perf_cache_event in arch/sh/kernel/perf_event.c,
212 		 * sparc_map_cache_event in arch/sparc/kernel/perf_event.c,
213 		 * xtensa_pmu_cache_event in arch/xtensa/kernel/perf_event.c,
214 		 * armpmu_map_cache_event in drivers/perf/arm_pmu.c) assumes
215 		 * that cache result is 8 bits in size.
216 		 */
217 		PRINT_XLAT("<<8|", perf_hw_cache_op_result_id,
218 		           (attr->config >> 16) & 0xFF,
219 		           "PERF_COUNT_HW_CACHE_RESULT_???");
220 		tprintf("<<16");
221 		if (attr->config >> 24)
222 			tprintf("|%#" PRIx64 "<<24 "
223 			        "/* PERF_COUNT_HW_CACHE_??? */",
224 			        attr->config >> 24);
225 		break;
226 	case PERF_TYPE_RAW:
227 		/*
228 		 * "If type is PERF_TYPE_RAW, then a custom "raw" config
229 		 * value is needed. Most CPUs support events that are not
230 		 * covered by the "generalized" events. These are
231 		 * implementation defined; see your CPU manual (for example the
232 		 * Intel Volume 3B documentation or the AMD BIOS and Kernel
233 		 * Developer Guide). The libpfm4 library can be used to
234 		 * translate from the name in the architectural manuals
235 		 * to the raw hex value perf_event_open() expects in this
236 		 * field."
237 		 */
238 	case PERF_TYPE_BREAKPOINT:
239 		/*
240 		 * "If type is PERF_TYPE_BREAKPOINT, then leave config set
241 		 * to zero. Its parameters are set in other places."
242 		 */
243 	default:
244 		tprintf(", config=%#" PRIx64, attr->config);
245 		break;
246 	}
247 
248 	if (abbrev(tcp))
249 		goto print_perf_event_attr_out;
250 
251 	if (attr->freq)
252 		tprintf(", sample_freq=%" PRIu64, attr->sample_freq);
253 	else
254 		tprintf(", sample_period=%" PRIu64, attr->sample_period);
255 
256 	tprintf(", sample_type=");
257 	printflags64(perf_event_sample_format, attr->sample_type,
258 		"PERF_SAMPLE_???");
259 
260 	tprintf(", read_format=");
261 	printflags64(perf_event_read_format, attr->read_format,
262 		"PERF_FORMAT_???");
263 
264 	tprintf(", disabled=%u"
265 	        ", inherit=%u"
266 	        ", pinned=%u"
267 	        ", exclusive=%u"
268 	        ", exclusive_user=%u"
269 	        ", exclude_kernel=%u"
270 	        ", exclude_hv=%u"
271 	        ", exclude_idle=%u"
272 	        ", mmap=%u"
273 	        ", comm=%u"
274 	        ", freq=%u"
275 	        ", inherit_stat=%u"
276 	        ", enable_on_exec=%u"
277 	        ", task=%u"
278 	        ", watermark=%u"
279 	        ", precise_ip=%u /* %s */"
280 	        ", mmap_data=%u"
281 	        ", sample_id_all=%u"
282 	        ", exclude_host=%u"
283 	        ", exclude_guest=%u"
284 	        ", exclude_callchain_kernel=%u"
285 	        ", exclude_callchain_user=%u"
286 	        ", mmap2=%u"
287 	        ", comm_exec=%u"
288 	        ", use_clockid=%u"
289 	        ", context_switch=%u"
290 	        ", write_backward=%u",
291 	        attr->disabled,
292 	        attr->inherit,
293 	        attr->pinned,
294 	        attr->exclusive,
295 	        attr->exclude_user,
296 	        attr->exclude_kernel,
297 	        attr->exclude_hv,
298 	        attr->exclude_idle,
299 	        attr->mmap,
300 	        attr->comm,
301 	        attr->freq,
302 	        attr->inherit_stat,
303 	        attr->enable_on_exec,
304 	        attr->task,
305 	        attr->watermark,
306 	        attr->precise_ip, precise_ip_desc[attr->precise_ip],
307 	        attr->mmap_data,
308 	        attr->sample_id_all,
309 	        attr->exclude_host,
310 	        attr->exclude_guest,
311 	        attr->exclude_callchain_kernel,
312 	        attr->exclude_callchain_user,
313 	        attr->mmap2,
314 	        attr->comm_exec,
315 	        attr->use_clockid,
316 	        attr->context_switch,
317 	        attr->write_backward);
318 
319 	/*
320 	 * Print it only in case it is non-zero, since it may contain flags we
321 	 * are not aware about.
322 	 */
323 	if (attr->__reserved_1)
324 		tprintf(", __reserved_1=%#" PRIx64 " /* Bits 63..28 */",
325 		        (uint64_t) attr->__reserved_1);
326 
327 	if (attr->watermark)
328 		tprintf(", wakeup_watermark=%u", attr->wakeup_watermark);
329 	else
330 		tprintf(", wakeup_events=%u", attr->wakeup_events);
331 
332 	if (attr->type == PERF_TYPE_BREAKPOINT)
333 		/* Any combination of R/W with X is deemed invalid */
334 		PRINT_XLAT(", bp_type=", hw_breakpoint_type, attr->bp_type,
335 		           (attr->bp_type <=
336 		                   (HW_BREAKPOINT_X | HW_BREAKPOINT_RW)) ?
337 		                           "HW_BREAKPOINT_INVALID" :
338 		                           "HW_BREAKPOINT_???");
339 
340 	if (attr->type == PERF_TYPE_BREAKPOINT)
341 		tprintf(", bp_addr=%#" PRIx64, attr->bp_addr);
342 	else
343 		tprintf(", config1=%#" PRIx64, attr->config1);
344 
345 	/*
346 	 * Fields after bp_addr/config1 are optional and may not present; check
347 	 * against size is needed.
348 	 */
349 
350 	_PERF_CHECK_FIELD(bp_len);
351 	if (attr->type == PERF_TYPE_BREAKPOINT)
352 		tprintf(", bp_len=%" PRIu64, attr->bp_len);
353 	else
354 		tprintf(", config2=%#" PRIx64, attr->config2);
355 
356 	_PERF_CHECK_FIELD(branch_sample_type);
357 	if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) {
358 		tprintf(", branch_sample_type=");
359 		printflags64(perf_branch_sample_type, attr->branch_sample_type,
360 		             "PERF_SAMPLE_BRANCH_???");
361 	}
362 
363 	_PERF_CHECK_FIELD(sample_regs_user);
364 	/*
365 	 * "This bit mask defines the set of user CPU registers to dump on
366 	 * samples. The layout of the register mask is architecture-specific and
367 	 * described in the kernel header
368 	 * arch/ARCH/include/uapi/asm/perf_regs.h."
369 	 */
370 	tprintf(", sample_regs_user=%#" PRIx64, attr->sample_regs_user);
371 
372 	_PERF_CHECK_FIELD(sample_stack_user);
373 	/*
374 	 * "size of the user stack to dump if PERF_SAMPLE_STACK_USER is
375 	 * specified."
376 	 */
377 	if (attr->sample_type & PERF_SAMPLE_STACK_USER)
378 		tprintf(", sample_stack_user=%#" PRIx32,
379 		        attr->sample_stack_user);
380 
381 	if (attr->use_clockid) {
382 		_PERF_CHECK_FIELD(clockid);
383 		tprintf(", clockid=");
384 		printxval(clocknames, attr->clockid, "CLOCK_???");
385 	}
386 
387 	_PERF_CHECK_FIELD(sample_regs_intr);
388 	tprintf(", sample_regs_intr=%#" PRIx64, attr->sample_regs_intr);
389 
390 	_PERF_CHECK_FIELD(aux_watermark);
391 	tprintf(", aux_watermark=%" PRIu32, attr->aux_watermark);
392 
393 	_PERF_CHECK_FIELD(sample_max_stack);
394 	tprintf(", sample_max_stack=%" PRIu16, attr->sample_max_stack);
395 
396 	/* _PERF_CHECK_FIELD(__reserved_2);
397 	tprintf(", __reserved2=%" PRIu16, attr->__reserved_2); */
398 
399 print_perf_event_attr_out:
400 	if ((attr->size && (attr->size > size)) ||
401 	    (!attr->size && (size < PERF_ATTR_SIZE_VER0)))
402 		tprintf(", ...");
403 
404 	tprintf("}");
405 }
406 
SYS_FUNC(perf_event_open)407 SYS_FUNC(perf_event_open)
408 {
409 	/*
410 	 * We try to copy out the whole structure on entering in order to check
411 	 * size value on exiting. We do not check the rest of the fields because
412 	 * they shouldn't be changed, but copy the whole structure instead
413 	 * of just size field because they could.
414 	 */
415 	if (entering(tcp)) {
416 		if (!fetch_perf_event_attr(tcp, tcp->u_arg[0]))
417 			return 0;
418 	} else {
419 		print_perf_event_attr(tcp, tcp->u_arg[0]);
420 	}
421 
422 	tprintf(", %d, %d, %d, ",
423 		(int) tcp->u_arg[1],
424 		(int) tcp->u_arg[2],
425 		(int) tcp->u_arg[3]);
426 	printflags64(perf_event_open_flags, tcp->u_arg[4], "PERF_FLAG_???");
427 
428 	return RVAL_DECODED | RVAL_FD;
429 }
430