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-rw-r--r--lib/dns/stats.c564
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diff --git a/lib/dns/stats.c b/lib/dns/stats.c
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--- /dev/null
+++ b/lib/dns/stats.c
@@ -0,0 +1,564 @@
+/*
+ * Copyright (C) 2004, 2005, 2007, 2008 Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 2000, 2001 Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: stats.c,v 1.16 2008/04/03 06:09:04 tbox Exp $ */
+
+/*! \file */
+
+#include <config.h>
+
+#include <string.h>
+
+#include <isc/atomic.h>
+#include <isc/buffer.h>
+#include <isc/magic.h>
+#include <isc/mem.h>
+#include <isc/platform.h>
+#include <isc/print.h>
+#include <isc/rwlock.h>
+#include <isc/util.h>
+
+#include <dns/opcode.h>
+#include <dns/rdatatype.h>
+#include <dns/stats.h>
+
+#define DNS_STATS_MAGIC ISC_MAGIC('D', 's', 't', 't')
+#define DNS_STATS_VALID(x) ISC_MAGIC_VALID(x, DNS_STATS_MAGIC)
+
+/*%
+ * Statistics types.
+ */
+typedef enum {
+ dns_statstype_general = 0,
+ dns_statstype_rdtype = 1,
+ dns_statstype_rdataset = 2,
+ dns_statstype_opcode = 3
+} dns_statstype_t;
+
+/*%
+ * It doesn't make sense to have 2^16 counters for all possible types since
+ * most of them won't be used. We have counters for the first 256 types and
+ * those explicitly supported in the rdata implementation.
+ * XXXJT: this introduces tight coupling with the rdata implementation.
+ * Ideally, we should have rdata handle this type of details.
+ */
+enum {
+ /* For 0-255, we use the rdtype value as counter indices */
+ rdtypecounter_dlv = 256, /* for dns_rdatatype_dlv */
+ rdtypecounter_others = 257, /* anything else */
+ rdtypecounter_max = 258,
+ /* The following are used for rdataset */
+ rdtypenxcounter_max = rdtypecounter_max * 2,
+ rdtypecounter_nxdomain = rdtypenxcounter_max,
+ rdatasettypecounter_max = rdtypecounter_nxdomain + 1
+};
+
+#ifndef DNS_STATS_USEMULTIFIELDS
+#if defined(ISC_RWLOCK_USEATOMIC) && defined(ISC_PLATFORM_HAVEXADD) && !defined(ISC_PLATFORM_HAVEXADDQ)
+#define DNS_STATS_USEMULTIFIELDS 1
+#else
+#define DNS_STATS_USEMULTIFIELDS 0
+#endif
+#endif /* DNS_STATS_USEMULTIFIELDS */
+
+#if DNS_STATS_USEMULTIFIELDS
+typedef struct {
+ isc_uint32_t hi;
+ isc_uint32_t lo;
+} dns_stat_t;
+#else
+typedef isc_uint64_t dns_stat_t;
+#endif
+
+struct dns_stats {
+ /*% Unlocked */
+ unsigned int magic;
+ dns_statstype_t type;
+ isc_mem_t *mctx;
+ int ncounters;
+
+ isc_mutex_t lock;
+ unsigned int references; /* locked by lock */
+
+ /*%
+ * Locked by counterlock or unlocked if efficient rwlock is not
+ * available.
+ */
+#ifdef ISC_RWLOCK_USEATOMIC
+ isc_rwlock_t counterlock;
+#endif
+ dns_stat_t *counters;
+
+ /*%
+ * We don't want to lock the counters while we are dumping, so we first
+ * copy the current counter values into a local array. This buffer
+ * will be used as the copy destination. It's allocated on creation
+ * of the stats structure so that the dump operation won't fail due
+ * to memory allocation failure.
+ * XXX: this approach is weird for non-threaded build because the
+ * additional memory and the copy overhead could be avoided. We prefer
+ * simplicity here, however, under the assumption that this function
+ * should be only rarely called.
+ */
+ isc_uint64_t *copiedcounters;
+};
+
+static isc_result_t
+create_stats(isc_mem_t *mctx, dns_statstype_t type, int ncounters,
+ dns_stats_t **statsp)
+{
+ dns_stats_t *stats;
+ isc_result_t result = ISC_R_SUCCESS;
+
+ REQUIRE(statsp != NULL && *statsp == NULL);
+
+ stats = isc_mem_get(mctx, sizeof(*stats));
+ if (stats == NULL)
+ return (ISC_R_NOMEMORY);
+
+ result = isc_mutex_init(&stats->lock);
+ if (result != ISC_R_SUCCESS)
+ goto clean_stats;
+
+ stats->counters = isc_mem_get(mctx, sizeof(dns_stat_t) * ncounters);
+ if (stats->counters == NULL) {
+ result = ISC_R_NOMEMORY;
+ goto clean_mutex;
+ }
+ stats->copiedcounters = isc_mem_get(mctx,
+ sizeof(isc_uint64_t) * ncounters);
+ if (stats->copiedcounters == NULL) {
+ result = ISC_R_NOMEMORY;
+ goto clean_counters;
+ }
+
+#ifdef ISC_RWLOCK_USEATOMIC
+ result = isc_rwlock_init(&stats->counterlock, 0, 0);
+ if (result != ISC_R_SUCCESS)
+ goto clean_copiedcounters;
+#endif
+
+ stats->type = type;
+ stats->references = 1;
+ memset(stats->counters, 0, sizeof(dns_stat_t) * ncounters);
+ stats->mctx = NULL;
+ isc_mem_attach(mctx, &stats->mctx);
+ stats->ncounters = ncounters;
+ stats->magic = DNS_STATS_MAGIC;
+
+ *statsp = stats;
+
+ return (result);
+
+clean_counters:
+ isc_mem_put(mctx, stats->counters, sizeof(dns_stat_t) * ncounters);
+
+#ifdef ISC_RWLOCK_USEATOMIC
+clean_copiedcounters:
+ isc_mem_put(mctx, stats->copiedcounters,
+ sizeof(dns_stat_t) * ncounters);
+#endif
+
+clean_mutex:
+ DESTROYLOCK(&stats->lock);
+
+clean_stats:
+ isc_mem_put(mctx, stats, sizeof(*stats));
+
+ return (result);
+}
+
+void
+dns_stats_attach(dns_stats_t *stats, dns_stats_t **statsp) {
+ REQUIRE(DNS_STATS_VALID(stats));
+ REQUIRE(statsp != NULL && *statsp == NULL);
+
+ LOCK(&stats->lock);
+ stats->references++;
+ UNLOCK(&stats->lock);
+
+ *statsp = stats;
+}
+
+void
+dns_stats_detach(dns_stats_t **statsp) {
+ dns_stats_t *stats;
+
+ REQUIRE(statsp != NULL && DNS_STATS_VALID(*statsp));
+
+ stats = *statsp;
+ *statsp = NULL;
+
+ LOCK(&stats->lock);
+ stats->references--;
+ UNLOCK(&stats->lock);
+
+ if (stats->references == 0) {
+ isc_mem_put(stats->mctx, stats->copiedcounters,
+ sizeof(dns_stat_t) * stats->ncounters);
+ isc_mem_put(stats->mctx, stats->counters,
+ sizeof(dns_stat_t) * stats->ncounters);
+ DESTROYLOCK(&stats->lock);
+#ifdef ISC_RWLOCK_USEATOMIC
+ isc_rwlock_destroy(&stats->counterlock);
+#endif
+ isc_mem_putanddetach(&stats->mctx, stats, sizeof(*stats));
+ }
+}
+
+static inline void
+incrementcounter(dns_stats_t *stats, int counter) {
+ isc_int32_t prev;
+
+#ifdef ISC_RWLOCK_USEATOMIC
+ /*
+ * We use a "read" lock to prevent other threads from reading the
+ * counter while we "writing" a counter field. The write access itself
+ * is protected by the atomic operation.
+ */
+ isc_rwlock_lock(&stats->counterlock, isc_rwlocktype_read);
+#endif
+
+#if DNS_STATS_USEMULTIFIELDS
+ prev = isc_atomic_xadd((isc_int32_t *)&stats->counters[counter].lo, 1);
+ /*
+ * If the lower 32-bit field overflows, increment the higher field.
+ * Note that it's *theoretically* possible that the lower field
+ * overlaps again before the higher field is incremented. It doesn't
+ * matter, however, because we don't read the value until
+ * dns_stats_copy() is called where the whole process is protected
+ * by the write (exclusive) lock.
+ */
+ if (prev == (isc_int32_t)0xffffffff)
+ isc_atomic_xadd((isc_int32_t *)&stats->counters[counter].hi, 1);
+#elif defined(ISC_PLATFORM_HAVEXADDQ)
+ UNUSED(prev);
+ isc_atomic_xaddq((isc_int64_t *)&stats->counters[counter], 1);
+#else
+ UNUSED(prev);
+ stats->counters[counter]++;
+#endif
+
+#ifdef ISC_RWLOCK_USEATOMIC
+ isc_rwlock_unlock(&stats->counterlock, isc_rwlocktype_read);
+#endif
+}
+
+static inline void
+decrementcounter(dns_stats_t *stats, int counter) {
+ isc_int32_t prev;
+
+#ifdef ISC_RWLOCK_USEATOMIC
+ isc_rwlock_lock(&stats->counterlock, isc_rwlocktype_read);
+#endif
+
+#if DNS_STATS_USEMULTIFIELDS
+ prev = isc_atomic_xadd((isc_int32_t *)&stats->counters[counter].lo, -1);
+ if (prev == 0)
+ isc_atomic_xadd((isc_int32_t *)&stats->counters[counter].hi,
+ -1);
+#elif defined(ISC_PLATFORM_HAVEXADDQ)
+ UNUSED(prev);
+ isc_atomic_xaddq((isc_int64_t *)&stats->counters[counter], -1);
+#else
+ UNUSED(prev);
+ stats->counters[counter]--;
+#endif
+
+#ifdef ISC_RWLOCK_USEATOMIC
+ isc_rwlock_unlock(&stats->counterlock, isc_rwlocktype_read);
+#endif
+}
+
+static void
+copy_counters(dns_stats_t *stats) {
+ int i;
+
+#ifdef ISC_RWLOCK_USEATOMIC
+ /*
+ * We use a "write" lock before "reading" the statistics counters as
+ * an exclusive lock.
+ */
+ isc_rwlock_lock(&stats->counterlock, isc_rwlocktype_write);
+#endif
+
+#if DNS_STATS_USEMULTIFIELDS
+ for (i = 0; i < stats->ncounters; i++) {
+ stats->copiedcounters[i] =
+ (isc_uint64_t)(stats->counters[i].hi) << 32 |
+ stats->counters[i].lo;
+ }
+#else
+ UNUSED(i);
+ memcpy(stats->copiedcounters, stats->counters,
+ stats->ncounters * sizeof(dns_stat_t));
+#endif
+
+#ifdef ISC_RWLOCK_USEATOMIC
+ isc_rwlock_unlock(&stats->counterlock, isc_rwlocktype_write);
+#endif
+}
+
+/*%
+ * Create methods
+ */
+isc_result_t
+dns_generalstats_create(isc_mem_t *mctx, dns_stats_t **statsp, int ncounters) {
+ REQUIRE(statsp != NULL && *statsp == NULL);
+
+ return (create_stats(mctx, dns_statstype_general, ncounters, statsp));
+}
+
+isc_result_t
+dns_rdatatypestats_create(isc_mem_t *mctx, dns_stats_t **statsp) {
+ REQUIRE(statsp != NULL && *statsp == NULL);
+
+ return (create_stats(mctx, dns_statstype_rdtype, rdtypecounter_max,
+ statsp));
+}
+
+isc_result_t
+dns_rdatasetstats_create(isc_mem_t *mctx, dns_stats_t **statsp) {
+ REQUIRE(statsp != NULL && *statsp == NULL);
+
+ return (create_stats(mctx, dns_statstype_rdataset,
+ (rdtypecounter_max * 2) + 1, statsp));
+}
+
+isc_result_t
+dns_opcodestats_create(isc_mem_t *mctx, dns_stats_t **statsp) {
+ REQUIRE(statsp != NULL && *statsp == NULL);
+
+ return (create_stats(mctx, dns_statstype_opcode, 16, statsp));
+}
+
+/*%
+ * Increment/Decrement methods
+ */
+void
+dns_generalstats_increment(dns_stats_t *stats, dns_statscounter_t counter) {
+ REQUIRE(DNS_STATS_VALID(stats) && stats->type == dns_statstype_general);
+ REQUIRE(counter < stats->ncounters);
+
+ incrementcounter(stats, (int)counter);
+}
+
+void
+dns_rdatatypestats_increment(dns_stats_t *stats, dns_rdatatype_t type) {
+ int counter;
+
+ REQUIRE(DNS_STATS_VALID(stats) && stats->type == dns_statstype_rdtype);
+
+ if (type == dns_rdatatype_dlv)
+ counter = rdtypecounter_dlv;
+ else if (type > dns_rdatatype_any)
+ counter = rdtypecounter_others;
+ else
+ counter = (int)type;
+
+ incrementcounter(stats, counter);
+}
+
+static inline void
+update_rdatasetstats(dns_stats_t *stats, dns_rdatastatstype_t rrsettype,
+ isc_boolean_t increment)
+{
+ int counter;
+ dns_rdatatype_t rdtype;
+
+ if ((DNS_RDATASTATSTYPE_ATTR(rrsettype) &
+ DNS_RDATASTATSTYPE_ATTR_NXDOMAIN) != 0) {
+ counter = rdtypecounter_nxdomain;
+ } else {
+ rdtype = DNS_RDATASTATSTYPE_BASE(rrsettype);
+ if (rdtype == dns_rdatatype_dlv)
+ counter = (int)rdtypecounter_dlv;
+ else if (rdtype > dns_rdatatype_any)
+ counter = (int)rdtypecounter_others;
+ else
+ counter = (int)rdtype;
+
+ if ((DNS_RDATASTATSTYPE_ATTR(rrsettype) &
+ DNS_RDATASTATSTYPE_ATTR_NXRRSET) != 0)
+ counter += rdtypecounter_max;
+ }
+
+ if (increment)
+ incrementcounter(stats, counter);
+ else
+ decrementcounter(stats, counter);
+}
+
+void
+dns_rdatasetstats_increment(dns_stats_t *stats, dns_rdatastatstype_t rrsettype)
+{
+ REQUIRE(DNS_STATS_VALID(stats) &&
+ stats->type == dns_statstype_rdataset);
+
+ update_rdatasetstats(stats, rrsettype, ISC_TRUE);
+}
+
+void
+dns_rdatasetstats_decrement(dns_stats_t *stats, dns_rdatastatstype_t rrsettype)
+{
+ REQUIRE(DNS_STATS_VALID(stats) &&
+ stats->type == dns_statstype_rdataset);
+
+ update_rdatasetstats(stats, rrsettype, ISC_FALSE);
+}
+void
+dns_opcodestats_increment(dns_stats_t *stats, dns_opcode_t code) {
+ REQUIRE(DNS_STATS_VALID(stats) && stats->type == dns_statstype_opcode);
+
+ incrementcounter(stats, (int)code);
+}
+
+/*%
+ * Dump methods
+ */
+void
+dns_generalstats_dump(dns_stats_t *stats, dns_generalstats_dumper_t dump_fn,
+ void *arg, unsigned int options)
+{
+ int i;
+
+ REQUIRE(DNS_STATS_VALID(stats) && stats->type == dns_statstype_general);
+
+ copy_counters(stats);
+
+ for (i = 0; i < stats->ncounters; i++) {
+ if ((options & DNS_STATSDUMP_VERBOSE) == 0 &&
+ stats->copiedcounters[i] == 0)
+ continue;
+ dump_fn(i, stats->copiedcounters[i], arg);
+ }
+}
+
+static void
+dump_rdentry(dns_stats_t *stats, int counter, int rdcounter,
+ dns_rdatastatstype_t attributes,
+ dns_rdatatypestats_dumper_t dump_fn, void * arg,
+ unsigned int options)
+{
+ dns_rdatatype_t rdtype = dns_rdatatype_none; /* sentinel */
+ dns_rdatastatstype_t type;
+
+ if ((options & DNS_STATSDUMP_VERBOSE) == 0 &&
+ stats->copiedcounters[counter] == 0)
+ return;
+ if (rdcounter == rdtypecounter_others)
+ attributes |= DNS_RDATASTATSTYPE_ATTR_OTHERTYPE;
+ else {
+ if (rdcounter == rdtypecounter_dlv)
+ rdtype = dns_rdatatype_dlv;
+ else
+ rdtype = (dns_rdatatype_t)rdcounter;
+ }
+ type = DNS_RDATASTATSTYPE_VALUE((dns_rdatastatstype_t)rdtype,
+ attributes);
+ dump_fn(type, stats->copiedcounters[counter], arg);
+}
+
+void
+dns_rdatatypestats_dump(dns_stats_t *stats, dns_rdatatypestats_dumper_t dump_fn,
+ void *arg, unsigned int options)
+{
+ int i;
+
+ REQUIRE(DNS_STATS_VALID(stats) && stats->type == dns_statstype_rdtype);
+
+ copy_counters(stats);
+
+ for (i = 0; i < stats->ncounters; i++)
+ dump_rdentry(stats, i, i, 0, dump_fn, arg, options);
+}
+
+void
+dns_rdatasetstats_dump(dns_stats_t *stats, dns_rdatatypestats_dumper_t dump_fn,
+ void *arg, unsigned int options)
+{
+ int i;
+
+ REQUIRE(DNS_STATS_VALID(stats) &&
+ stats->type == dns_statstype_rdataset);
+
+ copy_counters(stats);
+
+ for (i = 0; i < rdtypecounter_max; i++)
+ dump_rdentry(stats, i, i, 0, dump_fn, arg, options);
+ for (i = rdtypecounter_max; i < rdtypenxcounter_max; i++) {
+ dump_rdentry(stats, i, i - rdtypecounter_max,
+ DNS_RDATASTATSTYPE_ATTR_NXRRSET,
+ dump_fn, arg, options);
+ }
+ dump_rdentry(stats, rdtypecounter_nxdomain, 0,
+ DNS_RDATASTATSTYPE_ATTR_NXDOMAIN, dump_fn, arg, options);
+
+ INSIST(i < stats->ncounters);
+}
+
+void
+dns_opcodestats_dump(dns_stats_t *stats, dns_opcodestats_dumper_t dump_fn,
+ void *arg, unsigned int options)
+{
+ int i;
+
+ REQUIRE(DNS_STATS_VALID(stats) && stats->type == dns_statstype_opcode);
+
+ copy_counters(stats);
+
+ for (i = 0; i < stats->ncounters; i++) {
+ if ((options & DNS_STATSDUMP_VERBOSE) == 0 &&
+ stats->copiedcounters[i] == 0)
+ continue;
+ dump_fn((dns_opcode_t)i, stats->copiedcounters[i], arg);
+ }
+}
+
+/***
+ *** Obsolete variables and functions follow:
+ ***/
+LIBDNS_EXTERNAL_DATA const char *dns_statscounter_names[DNS_STATS_NCOUNTERS] =
+ {
+ "success",
+ "referral",
+ "nxrrset",
+ "nxdomain",
+ "recursion",
+ "failure",
+ "duplicate",
+ "dropped"
+ };
+
+isc_result_t
+dns_stats_alloccounters(isc_mem_t *mctx, isc_uint64_t **ctrp) {
+ int i;
+ isc_uint64_t *p =
+ isc_mem_get(mctx, DNS_STATS_NCOUNTERS * sizeof(isc_uint64_t));
+ if (p == NULL)
+ return (ISC_R_NOMEMORY);
+ for (i = 0; i < DNS_STATS_NCOUNTERS; i++)
+ p[i] = 0;
+ *ctrp = p;
+ return (ISC_R_SUCCESS);
+}
+
+void
+dns_stats_freecounters(isc_mem_t *mctx, isc_uint64_t **ctrp) {
+ isc_mem_put(mctx, *ctrp, DNS_STATS_NCOUNTERS * sizeof(isc_uint64_t));
+ *ctrp = NULL;
+}
generated by cgit (git 2.34.1) at 2024-04-26 03:20:54 +0000