[mirror_ubuntu-focal-kernel.git] / tools / perf / tests / sample-parsing.c

// SPDX-License-Identifier: GPL-2.0
#include <stdbool.h>
#include <inttypes.h>
#include <linux/kernel.h>
#include <linux/types.h>

#include "util.h"
#include "event.h"
#include "evsel.h"
#include "debug.h"

#include "tests.h"

#define COMP(m) do {					\
	if (s1->m != s2->m) {				\
		pr_debug("Samples differ at '"#m"'\n");	\
		return false;				\
	}						\
} while (0)

#define MCOMP(m) do {					\
	if (memcmp(&s1->m, &s2->m, sizeof(s1->m))) {	\
		pr_debug("Samples differ at '"#m"'\n");	\
		return false;				\
	}						\
} while (0)

static bool samples_same(const struct perf_sample *s1,
			 const struct perf_sample *s2,
			 u64 type, u64 read_format)
{
	size_t i;

	if (type & PERF_SAMPLE_IDENTIFIER)
		COMP(id);

	if (type & PERF_SAMPLE_IP)
		COMP(ip);

	if (type & PERF_SAMPLE_TID) {
		COMP(pid);
		COMP(tid);
	}

	if (type & PERF_SAMPLE_TIME)
		COMP(time);

	if (type & PERF_SAMPLE_ADDR)
		COMP(addr);

	if (type & PERF_SAMPLE_ID)
		COMP(id);

	if (type & PERF_SAMPLE_STREAM_ID)
		COMP(stream_id);

	if (type & PERF_SAMPLE_CPU)
		COMP(cpu);

	if (type & PERF_SAMPLE_PERIOD)
		COMP(period);

	if (type & PERF_SAMPLE_READ) {
		if (read_format & PERF_FORMAT_GROUP)
			COMP(read.group.nr);
		else
			COMP(read.one.value);
		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
			COMP(read.time_enabled);
		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
			COMP(read.time_running);
		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
		if (read_format & PERF_FORMAT_GROUP) {
			for (i = 0; i < s1->read.group.nr; i++)
				MCOMP(read.group.values[i]);
		} else {
			COMP(read.one.id);
		}
	}

	if (type & PERF_SAMPLE_CALLCHAIN) {
		COMP(callchain->nr);
		for (i = 0; i < s1->callchain->nr; i++)
			COMP(callchain->ips[i]);
	}

	if (type & PERF_SAMPLE_RAW) {
		COMP(raw_size);
		if (memcmp(s1->raw_data, s2->raw_data, s1->raw_size)) {
			pr_debug("Samples differ at 'raw_data'\n");
			return false;
		}
	}

	if (type & PERF_SAMPLE_BRANCH_STACK) {
		COMP(branch_stack->nr);
		for (i = 0; i < s1->branch_stack->nr; i++)
			MCOMP(branch_stack->entries[i]);
	}

	if (type & PERF_SAMPLE_REGS_USER) {
		size_t sz = hweight_long(s1->user_regs.mask) * sizeof(u64);

		COMP(user_regs.mask);
		COMP(user_regs.abi);
		if (s1->user_regs.abi &&
		    (!s1->user_regs.regs || !s2->user_regs.regs ||
		     memcmp(s1->user_regs.regs, s2->user_regs.regs, sz))) {
			pr_debug("Samples differ at 'user_regs'\n");
			return false;
		}
	}

	if (type & PERF_SAMPLE_STACK_USER) {
		COMP(user_stack.size);
		if (memcmp(s1->user_stack.data, s2->user_stack.data,
			   s1->user_stack.size)) {
			pr_debug("Samples differ at 'user_stack'\n");
			return false;
		}
	}

	if (type & PERF_SAMPLE_WEIGHT)
		COMP(weight);

	if (type & PERF_SAMPLE_DATA_SRC)
		COMP(data_src);

	if (type & PERF_SAMPLE_TRANSACTION)
		COMP(transaction);

	if (type & PERF_SAMPLE_REGS_INTR) {
		size_t sz = hweight_long(s1->intr_regs.mask) * sizeof(u64);

		COMP(intr_regs.mask);
		COMP(intr_regs.abi);
		if (s1->intr_regs.abi &&
		    (!s1->intr_regs.regs || !s2->intr_regs.regs ||
		     memcmp(s1->intr_regs.regs, s2->intr_regs.regs, sz))) {
			pr_debug("Samples differ at 'intr_regs'\n");
			return false;
		}
	}

	if (type & PERF_SAMPLE_PHYS_ADDR)
		COMP(phys_addr);

	return true;
}

static int do_test(u64 sample_type, u64 sample_regs, u64 read_format)
{
	struct perf_evsel evsel = {
		.needs_swap = false,
		.attr = {
			.sample_type = sample_type,
			.read_format = read_format,
		},
	};
	union perf_event *event;
	union {
		struct ip_callchain callchain;
		u64 data[64];
	} callchain = {
		/* 3 ips */
		.data = {3, 201, 202, 203},
	};
	union {
		struct branch_stack branch_stack;
		u64 data[64];
	} branch_stack = {
		/* 1 branch_entry */
		.data = {1, 211, 212, 213},
	};
	u64 regs[64];
	const u64 raw_data[] = {0x123456780a0b0c0dULL, 0x1102030405060708ULL};
	const u64 data[] = {0x2211443366558877ULL, 0, 0xaabbccddeeff4321ULL};
	struct perf_sample sample = {
		.ip		= 101,
		.pid		= 102,
		.tid		= 103,
		.time		= 104,
		.addr		= 105,
		.id		= 106,
		.stream_id	= 107,
		.period		= 108,
		.weight		= 109,
		.cpu		= 110,
		.raw_size	= sizeof(raw_data),
		.data_src	= 111,
		.transaction	= 112,
		.raw_data	= (void *)raw_data,
		.callchain	= &callchain.callchain,
		.branch_stack	= &branch_stack.branch_stack,
		.user_regs	= {
			.abi	= PERF_SAMPLE_REGS_ABI_64,
			.mask	= sample_regs,
			.regs	= regs,
		},
		.user_stack	= {
			.size	= sizeof(data),
			.data	= (void *)data,
		},
		.read		= {
			.time_enabled = 0x030a59d664fca7deULL,
			.time_running = 0x011b6ae553eb98edULL,
		},
		.intr_regs	= {
			.abi	= PERF_SAMPLE_REGS_ABI_64,
			.mask	= sample_regs,
			.regs	= regs,
		},
		.phys_addr	= 113,
	};
	struct sample_read_value values[] = {{1, 5}, {9, 3}, {2, 7}, {6, 4},};
	struct perf_sample sample_out;
	size_t i, sz, bufsz;
	int err, ret = -1;

	if (sample_type & PERF_SAMPLE_REGS_USER)
		evsel.attr.sample_regs_user = sample_regs;

	if (sample_type & PERF_SAMPLE_REGS_INTR)
		evsel.attr.sample_regs_intr = sample_regs;

	for (i = 0; i < sizeof(regs); i++)
		*(i + (u8 *)regs) = i & 0xfe;

	if (read_format & PERF_FORMAT_GROUP) {
		sample.read.group.nr     = 4;
		sample.read.group.values = values;
	} else {
		sample.read.one.value = 0x08789faeb786aa87ULL;
		sample.read.one.id    = 99;
	}

	sz = perf_event__sample_event_size(&sample, sample_type, read_format);
	bufsz = sz + 4096; /* Add a bit for overrun checking */
	event = malloc(bufsz);
	if (!event) {
		pr_debug("malloc failed\n");
		return -1;
	}

	memset(event, 0xff, bufsz);
	event->header.type = PERF_RECORD_SAMPLE;
	event->header.misc = 0;
	event->header.size = sz;

	err = perf_event__synthesize_sample(event, sample_type, read_format,
					    &sample, false);
	if (err) {
		pr_debug("%s failed for sample_type %#"PRIx64", error %d\n",
			 "perf_event__synthesize_sample", sample_type, err);
		goto out_free;
	}

	/* The data does not contain 0xff so we use that to check the size */
	for (i = bufsz; i > 0; i--) {
		if (*(i - 1 + (u8 *)event) != 0xff)
			break;
	}
	if (i != sz) {
		pr_debug("Event size mismatch: actual %zu vs expected %zu\n",
			 i, sz);
		goto out_free;
	}

	evsel.sample_size = __perf_evsel__sample_size(sample_type);

	err = perf_evsel__parse_sample(&evsel, event, &sample_out);
	if (err) {
		pr_debug("%s failed for sample_type %#"PRIx64", error %d\n",
			 "perf_evsel__parse_sample", sample_type, err);
		goto out_free;
	}

	if (!samples_same(&sample, &sample_out, sample_type, read_format)) {
		pr_debug("parsing failed for sample_type %#"PRIx64"\n",
			 sample_type);
		goto out_free;
	}

	ret = 0;
out_free:
	free(event);
	if (ret && read_format)
		pr_debug("read_format %#"PRIx64"\n", read_format);
	return ret;
}

/**
 * test__sample_parsing - test sample parsing.
 *
 * This function implements a test that synthesizes a sample event, parses it
 * and then checks that the parsed sample matches the original sample.  The test
 * checks sample format bits separately and together.  If the test passes %0 is
 * returned, otherwise %-1 is returned.
 */
int test__sample_parsing(struct test *test __maybe_unused, int subtest __maybe_unused)
{
	const u64 rf[] = {4, 5, 6, 7, 12, 13, 14, 15};
	u64 sample_type;
	u64 sample_regs;
	size_t i;
	int err;

	/*
	 * Fail the test if it has not been updated when new sample format bits
	 * were added.  Please actually update the test rather than just change
	 * the condition below.
	 */
	if (PERF_SAMPLE_MAX > PERF_SAMPLE_PHYS_ADDR << 1) {
		pr_debug("sample format has changed, some new PERF_SAMPLE_ bit was introduced - test needs updating\n");
		return -1;
	}

	/* Test each sample format bit separately */
	for (sample_type = 1; sample_type != PERF_SAMPLE_MAX;
	     sample_type <<= 1) {
		/* Test read_format variations */
		if (sample_type == PERF_SAMPLE_READ) {
			for (i = 0; i < ARRAY_SIZE(rf); i++) {
				err = do_test(sample_type, 0, rf[i]);
				if (err)
					return err;
			}
			continue;
		}
		sample_regs = 0;

		if (sample_type == PERF_SAMPLE_REGS_USER)
			sample_regs = 0x3fff;

		if (sample_type == PERF_SAMPLE_REGS_INTR)
			sample_regs = 0xff0fff;

		err = do_test(sample_type, sample_regs, 0);
		if (err)
			return err;
	}

	/* Test all sample format bits together */
	sample_type = PERF_SAMPLE_MAX - 1;
	sample_regs = 0x3fff; /* shared yb intr and user regs */
	for (i = 0; i < ARRAY_SIZE(rf); i++) {
		err = do_test(sample_type, sample_regs, rf[i]);
		if (err)
			return err;
	}

	return 0;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
045f8cd8	2	#include <stdbool.h>
fd20e811	3	#include <inttypes.h>
877a7a11	4	#include <linux/kernel.h>
d944c4ee	5	#include <linux/types.h>
045f8cd8 AH	6
	7	#include "util.h"
	8	#include "event.h"
	9	#include "evsel.h"
84f5d36f	10	#include "debug.h"
045f8cd8 AH	11
	12	#include "tests.h"
	13
	14	#define COMP(m) do { \
	15	if (s1->m != s2->m) { \
	16	pr_debug("Samples differ at '"#m"'\n"); \
	17	return false; \
	18	} \
	19	} while (0)
	20
	21	#define MCOMP(m) do { \
	22	if (memcmp(&s1->m, &s2->m, sizeof(s1->m))) { \
	23	pr_debug("Samples differ at '"#m"'\n"); \
	24	return false; \
	25	} \
	26	} while (0)
	27
	28	static bool samples_same(const struct perf_sample *s1,
352ea45a JO	29	const struct perf_sample *s2,
352ea45a JO	30	u64 type, u64 read_format)
045f8cd8 AH	31	{
	32	size_t i;
	33
	34	if (type & PERF_SAMPLE_IDENTIFIER)
	35	COMP(id);
	36
	37	if (type & PERF_SAMPLE_IP)
	38	COMP(ip);
	39
	40	if (type & PERF_SAMPLE_TID) {
	41	COMP(pid);
	42	COMP(tid);
	43	}
	44
	45	if (type & PERF_SAMPLE_TIME)
	46	COMP(time);
	47
	48	if (type & PERF_SAMPLE_ADDR)
	49	COMP(addr);
	50
	51	if (type & PERF_SAMPLE_ID)
	52	COMP(id);
	53
	54	if (type & PERF_SAMPLE_STREAM_ID)
	55	COMP(stream_id);
	56
	57	if (type & PERF_SAMPLE_CPU)
	58	COMP(cpu);
	59
	60	if (type & PERF_SAMPLE_PERIOD)
	61	COMP(period);
	62
	63	if (type & PERF_SAMPLE_READ) {
	64	if (read_format & PERF_FORMAT_GROUP)
	65	COMP(read.group.nr);
	66	else
	67	COMP(read.one.value);
	68	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
	69	COMP(read.time_enabled);
	70	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
	71	COMP(read.time_running);
	72	/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
	73	if (read_format & PERF_FORMAT_GROUP) {
	74	for (i = 0; i < s1->read.group.nr; i++)
	75	MCOMP(read.group.values[i]);
	76	} else {
	77	COMP(read.one.id);
	78	}
	79	}
	80
	81	if (type & PERF_SAMPLE_CALLCHAIN) {
	82	COMP(callchain->nr);
	83	for (i = 0; i < s1->callchain->nr; i++)
	84	COMP(callchain->ips[i]);
	85	}
	86
	87	if (type & PERF_SAMPLE_RAW) {
	88	COMP(raw_size);
	89	if (memcmp(s1->raw_data, s2->raw_data, s1->raw_size)) {
	90	pr_debug("Samples differ at 'raw_data'\n");
	91	return false;
	92	}
	93	}
	94
95	if (type & PERF_SAMPLE_BRANCH_STACK) {
96	COMP(branch_stack->nr);
97	for (i = 0; i < s1->branch_stack->nr; i++)
98	MCOMP(branch_stack->entries[i]);
99	}
100
101	if (type & PERF_SAMPLE_REGS_USER) {
352ea45a	102	size_t sz = hweight_long(s1->user_regs.mask) * sizeof(u64);
045f8cd8	103
352ea45a	104	COMP(user_regs.mask);
045f8cd8 AH	105	COMP(user_regs.abi);
	106	if (s1->user_regs.abi &&
	107	(!s1->user_regs.regs \|\| !s2->user_regs.regs \|\|
	108	memcmp(s1->user_regs.regs, s2->user_regs.regs, sz))) {
	109	pr_debug("Samples differ at 'user_regs'\n");
	110	return false;
	111	}
	112	}
	113
	114	if (type & PERF_SAMPLE_STACK_USER) {
	115	COMP(user_stack.size);
605a3069	116	if (memcmp(s1->user_stack.data, s2->user_stack.data,
045f8cd8 AH	117	s1->user_stack.size)) {
	118	pr_debug("Samples differ at 'user_stack'\n");
	119	return false;
	120	}
	121	}
	122
	123	if (type & PERF_SAMPLE_WEIGHT)
	124	COMP(weight);
	125
	126	if (type & PERF_SAMPLE_DATA_SRC)
	127	COMP(data_src);
	128
091a4ef5 AH	129	if (type & PERF_SAMPLE_TRANSACTION)
	130	COMP(transaction);
	131
26ff0f0a SE	132	if (type & PERF_SAMPLE_REGS_INTR) {
	133	size_t sz = hweight_long(s1->intr_regs.mask) * sizeof(u64);
	134
	135	COMP(intr_regs.mask);
	136	COMP(intr_regs.abi);
	137	if (s1->intr_regs.abi &&
	138	(!s1->intr_regs.regs \|\| !s2->intr_regs.regs \|\|
	139	memcmp(s1->intr_regs.regs, s2->intr_regs.regs, sz))) {
	140	pr_debug("Samples differ at 'intr_regs'\n");
	141	return false;
	142	}
	143	}
	144
fc33dccb KL	145	if (type & PERF_SAMPLE_PHYS_ADDR)
	146	COMP(phys_addr);
	147
045f8cd8 AH	148	return true;
	149	}
	150
26ff0f0a	151	static int do_test(u64 sample_type, u64 sample_regs, u64 read_format)
045f8cd8 AH	152	{
	153	struct perf_evsel evsel = {
	154	.needs_swap = false,
	155	.attr = {
	156	.sample_type = sample_type,
045f8cd8 AH	157	.read_format = read_format,
	158	},
	159	};
	160	union perf_event *event;
	161	union {
	162	struct ip_callchain callchain;
	163	u64 data[64];
	164	} callchain = {
	165	/* 3 ips */
	166	.data = {3, 201, 202, 203},
	167	};
	168	union {
	169	struct branch_stack branch_stack;
	170	u64 data[64];
	171	} branch_stack = {
	172	/* 1 branch_entry */
	173	.data = {1, 211, 212, 213},
	174	};
26ff0f0a	175	u64 regs[64];
045f8cd8 AH	176	const u64 raw_data[] = {0x123456780a0b0c0dULL, 0x1102030405060708ULL};
	177	const u64 data[] = {0x2211443366558877ULL, 0, 0xaabbccddeeff4321ULL};
	178	struct perf_sample sample = {
	179	.ip = 101,
	180	.pid = 102,
	181	.tid = 103,
	182	.time = 104,
	183	.addr = 105,
	184	.id = 106,
	185	.stream_id = 107,
	186	.period = 108,
	187	.weight = 109,
	188	.cpu = 110,
	189	.raw_size = sizeof(raw_data),
	190	.data_src = 111,
091a4ef5	191	.transaction = 112,
045f8cd8 AH	192	.raw_data = (void *)raw_data,
	193	.callchain = &callchain.callchain,
	194	.branch_stack = &branch_stack.branch_stack,
	195	.user_regs = {
	196	.abi = PERF_SAMPLE_REGS_ABI_64,
26ff0f0a SE	197	.mask = sample_regs,
26ff0f0a SE	198	.regs = regs,
045f8cd8 AH	199	},
	200	.user_stack = {
	201	.size = sizeof(data),
	202	.data = (void *)data,
	203	},
	204	.read = {
	205	.time_enabled = 0x030a59d664fca7deULL,
	206	.time_running = 0x011b6ae553eb98edULL,
	207	},
26ff0f0a SE	208	.intr_regs = {
	209	.abi = PERF_SAMPLE_REGS_ABI_64,
	210	.mask = sample_regs,
	211	.regs = regs,
	212	},
fc33dccb	213	.phys_addr = 113,
045f8cd8 AH	214	};
	215	struct sample_read_value values[] = {{1, 5}, {9, 3}, {2, 7}, {6, 4},};
	216	struct perf_sample sample_out;
	217	size_t i, sz, bufsz;
	218	int err, ret = -1;
	219
26ff0f0a SE	220	if (sample_type & PERF_SAMPLE_REGS_USER)
	221	evsel.attr.sample_regs_user = sample_regs;
	222
	223	if (sample_type & PERF_SAMPLE_REGS_INTR)
	224	evsel.attr.sample_regs_intr = sample_regs;
	225
	226	for (i = 0; i < sizeof(regs); i++)
	227	(i + (u8 )regs) = i & 0xfe;
045f8cd8 AH	228
	229	if (read_format & PERF_FORMAT_GROUP) {
	230	sample.read.group.nr = 4;
	231	sample.read.group.values = values;
	232	} else {
	233	sample.read.one.value = 0x08789faeb786aa87ULL;
	234	sample.read.one.id = 99;
	235	}
	236
352ea45a	237	sz = perf_event__sample_event_size(&sample, sample_type, read_format);
045f8cd8 AH	238	bufsz = sz + 4096; /* Add a bit for overrun checking */
	239	event = malloc(bufsz);
	240	if (!event) {
	241	pr_debug("malloc failed\n");
	242	return -1;
	243	}
	244
	245	memset(event, 0xff, bufsz);
	246	event->header.type = PERF_RECORD_SAMPLE;
	247	event->header.misc = 0;
	248	event->header.size = sz;
	249
352ea45a	250	err = perf_event__synthesize_sample(event, sample_type, read_format,
045f8cd8 AH	251	&sample, false);
	252	if (err) {
	253	pr_debug("%s failed for sample_type %#"PRIx64", error %d\n",
	254	"perf_event__synthesize_sample", sample_type, err);
	255	goto out_free;
	256	}
	257
	258	/* The data does not contain 0xff so we use that to check the size */
	259	for (i = bufsz; i > 0; i--) {
	260	if ((i - 1 + (u8 )event) != 0xff)
	261	break;
	262	}
	263	if (i != sz) {
	264	pr_debug("Event size mismatch: actual %zu vs expected %zu\n",
	265	i, sz);
	266	goto out_free;
	267	}
	268
	269	evsel.sample_size = __perf_evsel__sample_size(sample_type);
	270
	271	err = perf_evsel__parse_sample(&evsel, event, &sample_out);
	272	if (err) {
	273	pr_debug("%s failed for sample_type %#"PRIx64", error %d\n",
	274	"perf_evsel__parse_sample", sample_type, err);
	275	goto out_free;
	276	}
	277
352ea45a	278	if (!samples_same(&sample, &sample_out, sample_type, read_format)) {
045f8cd8 AH	279	pr_debug("parsing failed for sample_type %#"PRIx64"\n",
	280	sample_type);
	281	goto out_free;
	282	}
	283
	284	ret = 0;
	285	out_free:
	286	free(event);
	287	if (ret && read_format)
	288	pr_debug("read_format %#"PRIx64"\n", read_format);
	289	return ret;
	290	}
	291
	292	/**
	293	* test__sample_parsing - test sample parsing.
	294	*
	295	* This function implements a test that synthesizes a sample event, parses it
	296	* and then checks that the parsed sample matches the original sample. The test
	297	* checks sample format bits separately and together. If the test passes %0 is
	298	* returned, otherwise %-1 is returned.
	299	*/
81f17c90	300	int test__sample_parsing(struct test *test __maybe_unused, int subtest __maybe_unused)
045f8cd8 AH	301	{
	302	const u64 rf[] = {4, 5, 6, 7, 12, 13, 14, 15};
	303	u64 sample_type;
26ff0f0a	304	u64 sample_regs;
045f8cd8 AH	305	size_t i;
	306	int err;
	307
	308	/*
	309	* Fail the test if it has not been updated when new sample format bits
091a4ef5 AH	310	* were added. Please actually update the test rather than just change
091a4ef5 AH	311	* the condition below.
045f8cd8	312	*/
fc33dccb	313	if (PERF_SAMPLE_MAX > PERF_SAMPLE_PHYS_ADDR << 1) {
11a4d435	314	pr_debug("sample format has changed, some new PERF_SAMPLE_ bit was introduced - test needs updating\n");
045f8cd8 AH	315	return -1;
	316	}
	317
	318	/* Test each sample format bit separately */
	319	for (sample_type = 1; sample_type != PERF_SAMPLE_MAX;
	320	sample_type <<= 1) {
	321	/* Test read_format variations */
	322	if (sample_type == PERF_SAMPLE_READ) {
	323	for (i = 0; i < ARRAY_SIZE(rf); i++) {
	324	err = do_test(sample_type, 0, rf[i]);
	325	if (err)
	326	return err;
	327	}
	328	continue;
	329	}
26ff0f0a	330	sample_regs = 0;
045f8cd8 AH	331
045f8cd8 AH	332	if (sample_type == PERF_SAMPLE_REGS_USER)
26ff0f0a SE	333	sample_regs = 0x3fff;
	334
	335	if (sample_type == PERF_SAMPLE_REGS_INTR)
	336	sample_regs = 0xff0fff;
045f8cd8	337
26ff0f0a	338	err = do_test(sample_type, sample_regs, 0);
045f8cd8 AH	339	if (err)
	340	return err;
	341	}
	342
	343	/* Test all sample format bits together */
	344	sample_type = PERF_SAMPLE_MAX - 1;
26ff0f0a	345	sample_regs = 0x3fff; /* shared yb intr and user regs */
045f8cd8	346	for (i = 0; i < ARRAY_SIZE(rf); i++) {
26ff0f0a	347	err = do_test(sample_type, sample_regs, rf[i]);
045f8cd8 AH	348	if (err)
	349	return err;
	350	}
	351
	352	return 0;
	353	}