VLOG_DEFINE_THIS_MODULE(ofproto_dpif_upcall);
+COVERAGE_DEFINE(upcall_duplicate_flow);
+COVERAGE_DEFINE(revalidate_missed_dp_flow);
+
/* A thread that reads upcalls from dpif, forwards each upcall's packet,
* and possibly sets up a kernel flow as a cache. */
struct handler {
struct udpif *udpif; /* Parent udpif. */
pthread_t thread; /* Thread ID. */
- char *name; /* Thread name. */
uint32_t handler_id; /* Handler id. */
};
-/* A thread that processes each kernel flow handed to it by the flow_dumper
- * thread, updates OpenFlow statistics, and updates or removes the kernel flow
- * as necessary. */
+/* A thread that processes datapath flows, updates OpenFlow statistics, and
+ * updates or removes them if necessary. */
struct revalidator {
struct udpif *udpif; /* Parent udpif. */
- char *name; /* Thread name. */
-
pthread_t thread; /* Thread ID. */
- struct hmap ukeys; /* Datapath flow keys. */
-
- uint64_t dump_seq;
-
- struct ovs_mutex mutex; /* Mutex guarding the following. */
- pthread_cond_t wake_cond;
- struct list udumps OVS_GUARDED; /* Unprocessed udumps. */
- size_t n_udumps OVS_GUARDED; /* Number of unprocessed udumps. */
+ unsigned int id; /* ovsthread_id_self(). */
+ struct hmap *ukeys; /* Points into udpif->ukeys for this
+ revalidator. Used for GC phase. */
};
/* An upcall handler for ofproto_dpif.
* flow revalidation
* -----------------
*
- * - An array of 'struct revalidator's for flow revalidation and
- * stats collection.
- *
- * - A "flow_dumper" thread that reads the kernel flow table and dispatches
- * flows to one of several "revalidator" threads (see struct
- * revalidator).
- * */
+ * - Revalidation threads which read the datapath flow table and maintains
+ * them.
+ */
struct udpif {
struct list list_node; /* In all_udpifs list. */
uint32_t secret; /* Random seed for upcall hash. */
- pthread_t flow_dumper; /* Flow dumper thread ID. */
-
struct handler *handlers; /* Upcall handlers. */
size_t n_handlers;
struct revalidator *revalidators; /* Flow revalidators. */
size_t n_revalidators;
- uint64_t last_reval_seq; /* 'reval_seq' at last revalidation. */
- struct seq *reval_seq; /* Incremented to force revalidation. */
-
- struct seq *dump_seq; /* Increments each dump iteration. */
-
struct latch exit_latch; /* Tells child threads to exit. */
+ /* Revalidation. */
+ struct seq *reval_seq; /* Incremented to force revalidation. */
+ bool need_revalidate; /* As indicated by 'reval_seq'. */
+ bool reval_exit; /* Set by leader on 'exit_latch. */
+ struct ovs_barrier reval_barrier; /* Barrier used by revalidators. */
+ struct dpif_flow_dump dump; /* DPIF flow dump state. */
long long int dump_duration; /* Duration of the last flow dump. */
+ struct seq *dump_seq; /* Increments each dump iteration. */
+
+ /* There are 'n_revalidators' ukey hmaps. Each revalidator retains a
+ * reference to one of these for garbage collection.
+ *
+ * During the flow dump phase, revalidators insert into these with a random
+ * distribution. During the garbage collection phase, each revalidator
+ * takes care of garbage collecting one of these hmaps. */
+ struct {
+ struct ovs_mutex mutex; /* Guards the following. */
+ struct hmap hmap OVS_GUARDED; /* Datapath flow keys. */
+ } *ukeys;
/* Datapath flow statistics. */
unsigned int max_n_flows;
atomic_uint flow_limit; /* Datapath flow hard limit. */
/* n_flows_mutex prevents multiple threads updating these concurrently. */
- atomic_uint64_t n_flows; /* Number of flows in the datapath. */
+ atomic_ulong n_flows; /* Number of flows in the datapath. */
atomic_llong n_flows_timestamp; /* Last time n_flows was updated. */
struct ovs_mutex n_flows_mutex;
};
/* 'udpif_key's are responsible for tracking the little bit of state udpif
* needs to do flow expiration which can't be pulled directly from the
- * datapath. They are owned, created by, maintained, and destroyed by a single
- * revalidator making them easy to efficiently handle with multiple threads. */
+ * datapath. They may be created or maintained by any revalidator during
+ * the dump phase, but are owned by a single revalidator, and are destroyed
+ * by that revalidator during the garbage-collection phase.
+ *
+ * While some elements of a udpif_key are protected by a mutex, the ukey itself
+ * is not. Therefore it is not safe to destroy a udpif_key except when all
+ * revalidators are in garbage collection phase, or they aren't running. */
struct udpif_key {
struct hmap_node hmap_node; /* In parent revalidator 'ukeys' map. */
- struct nlattr *key; /* Datapath flow key. */
+ /* These elements are read only once created, and therefore aren't
+ * protected by a mutex. */
+ const struct nlattr *key; /* Datapath flow key. */
size_t key_len; /* Length of 'key'. */
- struct dpif_flow_stats stats; /* Stats at most recent flow dump. */
- long long int created; /* Estimation of creation time. */
-
- bool mark; /* Used by mark and sweep GC algorithm. */
-
- struct odputil_keybuf key_buf; /* Memory for 'key'. */
- struct xlate_cache *xcache; /* Cache for xlate entries that
- * are affected by this ukey.
- * Used for stats and learning.*/
-};
-
-/* 'udpif_flow_dump's hold the state associated with one iteration in a flow
- * dump operation. This is created by the flow_dumper thread and handed to the
- * appropriate revalidator thread to be processed. */
-struct udpif_flow_dump {
- struct list list_node;
-
- struct nlattr *key; /* Datapath flow key. */
- size_t key_len; /* Length of 'key'. */
- uint32_t key_hash; /* Hash of 'key'. */
-
- struct odputil_keybuf mask_buf;
- struct nlattr *mask; /* Datapath mask for 'key'. */
- size_t mask_len; /* Length of 'mask'. */
-
- struct dpif_flow_stats stats; /* Stats pulled from the datapath. */
-
- bool need_revalidate; /* Key needs revalidation? */
-
- struct odputil_keybuf key_buf;
+ struct ovs_mutex mutex; /* Guards the following. */
+ struct dpif_flow_stats stats OVS_GUARDED; /* Last known stats.*/
+ long long int created OVS_GUARDED; /* Estimate of creation time. */
+ bool mark OVS_GUARDED; /* For mark and sweep garbage
+ collection. */
+ bool flow_exists OVS_GUARDED; /* Ensures flows are only deleted
+ once. */
+
+ struct xlate_cache *xcache OVS_GUARDED; /* Cache for xlate entries that
+ * are affected by this ukey.
+ * Used for stats and learning.*/
+ struct odputil_keybuf key_buf; /* Memory for 'key'. */
};
/* Flow miss batching.
static void udpif_stop_threads(struct udpif *);
static void udpif_start_threads(struct udpif *, size_t n_handlers,
size_t n_revalidators);
-static void *udpif_flow_dumper(void *);
static void *udpif_upcall_handler(void *);
static void *udpif_revalidator(void *);
-static uint64_t udpif_get_n_flows(struct udpif *);
-static void revalidate_udumps(struct revalidator *, struct list *udumps);
+static unsigned long udpif_get_n_flows(struct udpif *);
+static void revalidate(struct revalidator *);
static void revalidator_sweep(struct revalidator *);
static void revalidator_purge(struct revalidator *);
static void upcall_unixctl_show(struct unixctl_conn *conn, int argc,
const char *argv[], void *aux);
static void upcall_unixctl_set_flow_limit(struct unixctl_conn *conn, int argc,
const char *argv[], void *aux);
+
+static struct udpif_key *ukey_create(const struct nlattr *key, size_t key_len,
+ long long int used);
static void ukey_delete(struct revalidator *, struct udpif_key *);
static atomic_bool enable_megaflows = ATOMIC_VAR_INIT(true);
}
for (i = 0; i < udpif->n_revalidators; i++) {
- struct revalidator *revalidator = &udpif->revalidators[i];
-
- ovs_mutex_lock(&revalidator->mutex);
- xpthread_cond_signal(&revalidator->wake_cond);
- ovs_mutex_unlock(&revalidator->mutex);
- xpthread_join(revalidator->thread, NULL);
+ xpthread_join(udpif->revalidators[i].thread, NULL);
}
- xpthread_join(udpif->flow_dumper, NULL);
-
for (i = 0; i < udpif->n_revalidators; i++) {
struct revalidator *revalidator = &udpif->revalidators[i];
- struct udpif_flow_dump *udump, *next_udump;
-
- LIST_FOR_EACH_SAFE (udump, next_udump, list_node,
- &revalidator->udumps) {
- list_remove(&udump->list_node);
- free(udump);
- }
/* Delete ukeys, and delete all flows from the datapath to prevent
* double-counting stats. */
revalidator_purge(revalidator);
- hmap_destroy(&revalidator->ukeys);
- ovs_mutex_destroy(&revalidator->mutex);
- free(revalidator->name);
+ hmap_destroy(&udpif->ukeys[i].hmap);
+ ovs_mutex_destroy(&udpif->ukeys[i].mutex);
}
- for (i = 0; i < udpif->n_handlers; i++) {
- free(udpif->handlers[i].name);
- }
latch_poll(&udpif->exit_latch);
+ ovs_barrier_destroy(&udpif->reval_barrier);
+
free(udpif->revalidators);
udpif->revalidators = NULL;
udpif->n_revalidators = 0;
free(udpif->handlers);
udpif->handlers = NULL;
udpif->n_handlers = 0;
+
+ free(udpif->ukeys);
+ udpif->ukeys = NULL;
}
}
udpif_start_threads(struct udpif *udpif, size_t n_handlers,
size_t n_revalidators)
{
- if (udpif && (!udpif->handlers && !udpif->revalidators)) {
+ if (udpif && n_handlers && n_revalidators) {
size_t i;
udpif->n_handlers = n_handlers;
handler->udpif = udpif;
handler->handler_id = i;
- xpthread_create(&handler->thread, NULL, udpif_upcall_handler,
- handler);
+ handler->thread = ovs_thread_create(
+ "handler", udpif_upcall_handler, handler);
}
+ ovs_barrier_init(&udpif->reval_barrier, udpif->n_revalidators);
+ udpif->reval_exit = false;
udpif->revalidators = xzalloc(udpif->n_revalidators
* sizeof *udpif->revalidators);
+ udpif->ukeys = xmalloc(sizeof *udpif->ukeys * n_revalidators);
for (i = 0; i < udpif->n_revalidators; i++) {
struct revalidator *revalidator = &udpif->revalidators[i];
revalidator->udpif = udpif;
- list_init(&revalidator->udumps);
- hmap_init(&revalidator->ukeys);
- ovs_mutex_init(&revalidator->mutex);
- xpthread_cond_init(&revalidator->wake_cond, NULL);
- xpthread_create(&revalidator->thread, NULL, udpif_revalidator,
- revalidator);
+ hmap_init(&udpif->ukeys[i].hmap);
+ ovs_mutex_init(&udpif->ukeys[i].mutex);
+ revalidator->ukeys = &udpif->ukeys[i].hmap;
+ revalidator->thread = ovs_thread_create(
+ "revalidator", udpif_revalidator, revalidator);
}
- xpthread_create(&udpif->flow_dumper, NULL, udpif_flow_dumper, udpif);
}
}
udpif_set_threads(struct udpif *udpif, size_t n_handlers,
size_t n_revalidators)
{
- int error;
-
ovs_assert(udpif);
ovs_assert(n_handlers && n_revalidators);
udpif_stop_threads(udpif);
}
- error = dpif_handlers_set(udpif->dpif, n_handlers);
- if (error) {
- VLOG_ERR("failed to configure handlers in dpif %s: %s",
- dpif_name(udpif->dpif), ovs_strerror(error));
- return;
- }
-
if (!udpif->handlers && !udpif->revalidators) {
+ int error;
+
+ error = dpif_handlers_set(udpif->dpif, n_handlers);
+ if (error) {
+ VLOG_ERR("failed to configure handlers in dpif %s: %s",
+ dpif_name(udpif->dpif), ovs_strerror(error));
+ return;
+ }
+
udpif_start_threads(udpif, n_handlers, n_revalidators);
}
ovsrcu_quiesce_end();
{
size_t i;
- simap_increase(usage, "flow_dumpers", 1);
-
simap_increase(usage, "handlers", udpif->n_handlers);
simap_increase(usage, "revalidators", udpif->n_revalidators);
for (i = 0; i < udpif->n_revalidators; i++) {
- struct revalidator *revalidator = &udpif->revalidators[i];
- ovs_mutex_lock(&revalidator->mutex);
- simap_increase(usage, "revalidator dumps", revalidator->n_udumps);
-
- /* XXX: This isn't technically thread safe because the revalidator
- * ukeys maps isn't protected by a mutex since it's per thread. */
- simap_increase(usage, "revalidator keys",
- hmap_count(&revalidator->ukeys));
- ovs_mutex_unlock(&revalidator->mutex);
+ ovs_mutex_lock(&udpif->ukeys[i].mutex);
+ simap_increase(usage, "udpif keys", hmap_count(&udpif->ukeys[i].hmap));
+ ovs_mutex_unlock(&udpif->ukeys[i].mutex);
}
}
}
\f
-static uint64_t
+static unsigned long
udpif_get_n_flows(struct udpif *udpif)
{
long long int time, now;
- uint64_t flow_count;
+ unsigned long flow_count;
now = time_msec();
atomic_read(&udpif->n_flows_timestamp, &time);
return flow_count;
}
-static void *
-udpif_flow_dumper(void *arg)
-{
- struct udpif *udpif = arg;
-
- set_subprogram_name("flow_dumper");
- while (!latch_is_set(&udpif->exit_latch)) {
- const struct dpif_flow_stats *stats;
- long long int start_time, duration;
- const struct nlattr *key, *mask;
- struct dpif_flow_dump dump;
- size_t key_len, mask_len;
- unsigned int flow_limit;
- bool need_revalidate;
- uint64_t reval_seq;
- size_t n_flows, i;
- int error;
- void *state = NULL;
-
- reval_seq = seq_read(udpif->reval_seq);
- need_revalidate = udpif->last_reval_seq != reval_seq;
- udpif->last_reval_seq = reval_seq;
-
- n_flows = udpif_get_n_flows(udpif);
- udpif->max_n_flows = MAX(n_flows, udpif->max_n_flows);
- udpif->avg_n_flows = (udpif->avg_n_flows + n_flows) / 2;
-
- start_time = time_msec();
- error = dpif_flow_dump_start(&dump, udpif->dpif);
- if (error) {
- VLOG_INFO("Failed to start flow dump (%s)", ovs_strerror(error));
- goto skip;
- }
- dpif_flow_dump_state_init(udpif->dpif, &state);
- while (dpif_flow_dump_next(&dump, state, &key, &key_len,
- &mask, &mask_len, NULL, NULL, &stats)
- && !latch_is_set(&udpif->exit_latch)) {
- struct udpif_flow_dump *udump = xmalloc(sizeof *udump);
- struct revalidator *revalidator;
-
- udump->key_hash = hash_bytes(key, key_len, udpif->secret);
- memcpy(&udump->key_buf, key, key_len);
- udump->key = (struct nlattr *) &udump->key_buf;
- udump->key_len = key_len;
-
- memcpy(&udump->mask_buf, mask, mask_len);
- udump->mask = (struct nlattr *) &udump->mask_buf;
- udump->mask_len = mask_len;
-
- udump->stats = *stats;
- udump->need_revalidate = need_revalidate;
-
- revalidator = &udpif->revalidators[udump->key_hash
- % udpif->n_revalidators];
-
- ovs_mutex_lock(&revalidator->mutex);
- while (revalidator->n_udumps >= REVALIDATE_MAX_BATCH * 3
- && !latch_is_set(&udpif->exit_latch)) {
- ovs_mutex_cond_wait(&revalidator->wake_cond,
- &revalidator->mutex);
- }
- list_push_back(&revalidator->udumps, &udump->list_node);
- revalidator->n_udumps++;
- xpthread_cond_signal(&revalidator->wake_cond);
- ovs_mutex_unlock(&revalidator->mutex);
- }
- dpif_flow_dump_state_uninit(udpif->dpif, state);
- dpif_flow_dump_done(&dump);
-
- /* Let all the revalidators finish and garbage collect. */
- seq_change(udpif->dump_seq);
- for (i = 0; i < udpif->n_revalidators; i++) {
- struct revalidator *revalidator = &udpif->revalidators[i];
- ovs_mutex_lock(&revalidator->mutex);
- xpthread_cond_signal(&revalidator->wake_cond);
- ovs_mutex_unlock(&revalidator->mutex);
- }
-
- for (i = 0; i < udpif->n_revalidators; i++) {
- struct revalidator *revalidator = &udpif->revalidators[i];
-
- ovs_mutex_lock(&revalidator->mutex);
- while (revalidator->dump_seq != seq_read(udpif->dump_seq)
- && !latch_is_set(&udpif->exit_latch)) {
- ovs_mutex_cond_wait(&revalidator->wake_cond,
- &revalidator->mutex);
- }
- ovs_mutex_unlock(&revalidator->mutex);
- }
-
- duration = MAX(time_msec() - start_time, 1);
- udpif->dump_duration = duration;
- atomic_read(&udpif->flow_limit, &flow_limit);
- if (duration > 2000) {
- flow_limit /= duration / 1000;
- } else if (duration > 1300) {
- flow_limit = flow_limit * 3 / 4;
- } else if (duration < 1000 && n_flows > 2000
- && flow_limit < n_flows * 1000 / duration) {
- flow_limit += 1000;
- }
- flow_limit = MIN(ofproto_flow_limit, MAX(flow_limit, 1000));
- atomic_store(&udpif->flow_limit, flow_limit);
-
- if (duration > 2000) {
- VLOG_INFO("Spent an unreasonably long %lldms dumping flows",
- duration);
- }
-
-skip:
- poll_timer_wait_until(start_time + MIN(ofproto_max_idle, 500));
- seq_wait(udpif->reval_seq, udpif->last_reval_seq);
- latch_wait(&udpif->exit_latch);
- poll_block();
- }
-
- return NULL;
-}
-
/* The upcall handler thread tries to read a batch of FLOW_MISS_MAX_BATCH
* upcalls from dpif, processes the batch and installs corresponding flows
* in dpif. */
struct udpif *udpif = handler->udpif;
struct hmap misses = HMAP_INITIALIZER(&misses);
- handler->name = xasprintf("handler_%u", ovsthread_id_self());
- set_subprogram_name("%s", handler->name);
-
while (!latch_is_set(&handler->udpif->exit_latch)) {
struct upcall upcalls[FLOW_MISS_MAX_BATCH];
struct flow_miss miss_buf[FLOW_MISS_MAX_BATCH];
static void *
udpif_revalidator(void *arg)
{
+ /* Used by all revalidators. */
struct revalidator *revalidator = arg;
+ struct udpif *udpif = revalidator->udpif;
+ bool leader = revalidator == &udpif->revalidators[0];
+
+ /* Used only by the leader. */
+ long long int start_time = 0;
+ uint64_t last_reval_seq = 0;
+ unsigned int flow_limit = 0;
+ size_t n_flows = 0;
- revalidator->name = xasprintf("revalidator_%u", ovsthread_id_self());
- set_subprogram_name("%s", revalidator->name);
+ revalidator->id = ovsthread_id_self();
for (;;) {
- struct list udumps = LIST_INITIALIZER(&udumps);
- struct udpif *udpif = revalidator->udpif;
- size_t i;
+ if (leader) {
+ uint64_t reval_seq;
- ovs_mutex_lock(&revalidator->mutex);
- if (latch_is_set(&udpif->exit_latch)) {
- ovs_mutex_unlock(&revalidator->mutex);
- return NULL;
- }
+ reval_seq = seq_read(udpif->reval_seq);
+ udpif->need_revalidate = last_reval_seq != reval_seq;
+ last_reval_seq = reval_seq;
- if (!revalidator->n_udumps) {
- if (revalidator->dump_seq != seq_read(udpif->dump_seq)) {
- revalidator->dump_seq = seq_read(udpif->dump_seq);
- revalidator_sweep(revalidator);
- } else {
- ovs_mutex_cond_wait(&revalidator->wake_cond,
- &revalidator->mutex);
+ n_flows = udpif_get_n_flows(udpif);
+ udpif->max_n_flows = MAX(n_flows, udpif->max_n_flows);
+ udpif->avg_n_flows = (udpif->avg_n_flows + n_flows) / 2;
+
+ /* Only the leader checks the exit latch to prevent a race where
+ * some threads think it's true and exit and others think it's
+ * false and block indefinitely on the reval_barrier */
+ udpif->reval_exit = latch_is_set(&udpif->exit_latch);
+
+ start_time = time_msec();
+ if (!udpif->reval_exit) {
+ dpif_flow_dump_start(&udpif->dump, udpif->dpif);
}
}
- for (i = 0; i < REVALIDATE_MAX_BATCH && revalidator->n_udumps; i++) {
- list_push_back(&udumps, list_pop_front(&revalidator->udumps));
- revalidator->n_udumps--;
+ /* Wait for the leader to start the flow dump. */
+ ovs_barrier_block(&udpif->reval_barrier);
+ if (udpif->reval_exit) {
+ break;
}
+ revalidate(revalidator);
+
+ /* Wait for all flows to have been dumped before we garbage collect. */
+ ovs_barrier_block(&udpif->reval_barrier);
+ revalidator_sweep(revalidator);
+
+ /* Wait for all revalidators to finish garbage collection. */
+ ovs_barrier_block(&udpif->reval_barrier);
+
+ if (leader) {
+ long long int duration;
+
+ dpif_flow_dump_done(&udpif->dump);
+ seq_change(udpif->dump_seq);
+
+ duration = MAX(time_msec() - start_time, 1);
+ atomic_read(&udpif->flow_limit, &flow_limit);
+ udpif->dump_duration = duration;
+ if (duration > 2000) {
+ flow_limit /= duration / 1000;
+ } else if (duration > 1300) {
+ flow_limit = flow_limit * 3 / 4;
+ } else if (duration < 1000 && n_flows > 2000
+ && flow_limit < n_flows * 1000 / duration) {
+ flow_limit += 1000;
+ }
+ flow_limit = MIN(ofproto_flow_limit, MAX(flow_limit, 1000));
+ atomic_store(&udpif->flow_limit, flow_limit);
- /* Wake up the flow dumper. */
- xpthread_cond_signal(&revalidator->wake_cond);
- ovs_mutex_unlock(&revalidator->mutex);
+ if (duration > 2000) {
+ VLOG_INFO("Spent an unreasonably long %lldms dumping flows",
+ duration);
+ }
- if (!list_is_empty(&udumps)) {
- revalidate_udumps(revalidator, &udumps);
+ poll_timer_wait_until(start_time + MIN(ofproto_max_idle, 500));
+ seq_wait(udpif->reval_seq, last_reval_seq);
+ latch_wait(&udpif->exit_latch);
+ poll_block();
}
}
* in the kernel. */
VLOG_INFO_RL(&rl, "received packet on unassociated datapath "
"port %"PRIu32, odp_in_port);
- dpif_flow_put(udpif->dpif, DPIF_FP_CREATE | DPIF_FP_MODIFY,
+ dpif_flow_put(udpif->dpif, DPIF_FP_CREATE,
dupcall->key, dupcall->key_len, NULL, 0, NULL, 0,
NULL);
}
op = &ops[n_ops++];
op->type = DPIF_OP_FLOW_PUT;
- op->u.flow_put.flags = DPIF_FP_CREATE | DPIF_FP_MODIFY;
+ op->u.flow_put.flags = DPIF_FP_CREATE;
op->u.flow_put.key = miss->key;
op->u.flow_put.key_len = miss->key_len;
op->u.flow_put.mask = ofpbuf_data(&mask);
dpif_operate(udpif->dpif, opsp, n_ops);
}
+/* Must be called with udpif->ukeys[hash % udpif->n_revalidators].mutex. */
static struct udpif_key *
-ukey_lookup(struct revalidator *revalidator, struct udpif_flow_dump *udump)
+ukey_lookup__(struct udpif *udpif, const struct nlattr *key, size_t key_len,
+ uint32_t hash)
{
struct udpif_key *ukey;
+ struct hmap *hmap = &udpif->ukeys[hash % udpif->n_revalidators].hmap;
- HMAP_FOR_EACH_WITH_HASH (ukey, hmap_node, udump->key_hash,
- &revalidator->ukeys) {
- if (ukey->key_len == udump->key_len
- && !memcmp(ukey->key, udump->key, udump->key_len)) {
+ HMAP_FOR_EACH_WITH_HASH (ukey, hmap_node, hash, hmap) {
+ if (ukey->key_len == key_len && !memcmp(ukey->key, key, key_len)) {
return ukey;
}
}
return NULL;
}
+static struct udpif_key *
+ukey_lookup(struct udpif *udpif, const struct nlattr *key, size_t key_len,
+ uint32_t hash)
+{
+ struct udpif_key *ukey;
+ uint32_t idx = hash % udpif->n_revalidators;
+
+ ovs_mutex_lock(&udpif->ukeys[idx].mutex);
+ ukey = ukey_lookup__(udpif, key, key_len, hash);
+ ovs_mutex_unlock(&udpif->ukeys[idx].mutex);
+
+ return ukey;
+}
+
static struct udpif_key *
ukey_create(const struct nlattr *key, size_t key_len, long long int used)
{
struct udpif_key *ukey = xmalloc(sizeof *ukey);
+ ovs_mutex_init(&ukey->mutex);
ukey->key = (struct nlattr *) &ukey->key_buf;
memcpy(&ukey->key_buf, key, key_len);
ukey->key_len = key_len;
+ ovs_mutex_lock(&ukey->mutex);
ukey->mark = false;
+ ukey->flow_exists = true;
ukey->created = used ? used : time_msec();
memset(&ukey->stats, 0, sizeof ukey->stats);
ukey->xcache = NULL;
+ ovs_mutex_unlock(&ukey->mutex);
return ukey;
}
+/* Checks for a ukey in 'udpif->ukeys' with the same 'ukey->key' and 'hash',
+ * and inserts 'ukey' if it does not exist.
+ *
+ * Returns true if 'ukey' was inserted into 'udpif->ukeys', false otherwise. */
+static bool
+udpif_insert_ukey(struct udpif *udpif, struct udpif_key *ukey, uint32_t hash)
+{
+ struct udpif_key *duplicate;
+ uint32_t idx = hash % udpif->n_revalidators;
+ bool ok;
+
+ ovs_mutex_lock(&udpif->ukeys[idx].mutex);
+ duplicate = ukey_lookup__(udpif, ukey->key, ukey->key_len, hash);
+ if (duplicate) {
+ ok = false;
+ } else {
+ hmap_insert(&udpif->ukeys[idx].hmap, &ukey->hmap_node, hash);
+ ok = true;
+ }
+ ovs_mutex_unlock(&udpif->ukeys[idx].mutex);
+
+ return ok;
+}
+
static void
ukey_delete(struct revalidator *revalidator, struct udpif_key *ukey)
+ OVS_NO_THREAD_SAFETY_ANALYSIS
{
- hmap_remove(&revalidator->ukeys, &ukey->hmap_node);
+ if (revalidator) {
+ hmap_remove(revalidator->ukeys, &ukey->hmap_node);
+ }
xlate_cache_delete(ukey->xcache);
+ ovs_mutex_destroy(&ukey->mutex);
free(ukey);
}
static bool
-should_revalidate(uint64_t packets, long long int used)
+should_revalidate(const struct udpif *udpif, uint64_t packets,
+ long long int used)
{
long long int metric, now, duration;
+ if (udpif->dump_duration < 200) {
+ /* We are likely to handle full revalidation for the flows. */
+ return true;
+ }
+
/* Calculate the mean time between seeing these packets. If this
* exceeds the threshold, then delete the flow rather than performing
* costly revalidation for flows that aren't being hit frequently.
duration = now - used;
metric = duration / packets;
- if (metric > 200) {
- return false;
+ if (metric < 200) {
+ /* The flow is receiving more than ~5pps, so keep it. */
+ return true;
}
- return true;
+ return false;
}
static bool
-revalidate_ukey(struct udpif *udpif, struct udpif_flow_dump *udump,
- struct udpif_key *ukey)
+revalidate_ukey(struct udpif *udpif, struct udpif_key *ukey,
+ const struct nlattr *mask, size_t mask_len,
+ const struct nlattr *actions, size_t actions_len,
+ const struct dpif_flow_stats *stats)
+ OVS_REQUIRES(ukey->mutex)
{
- struct ofpbuf xout_actions, *actions;
uint64_t slow_path_buf[128 / 8];
struct xlate_out xout, *xoutp;
struct netflow *netflow;
- struct flow flow, udump_mask;
struct ofproto_dpif *ofproto;
struct dpif_flow_stats push;
- uint32_t *udump32, *xout32;
+ struct ofpbuf xout_actions;
+ struct flow flow, dp_mask;
+ uint32_t *dp32, *xout32;
odp_port_t odp_in_port;
struct xlate_in xin;
long long int last_used;
ok = false;
xoutp = NULL;
- actions = NULL;
netflow = NULL;
- /* If we don't need to revalidate, we can simply push the stats contained
- * in the udump, otherwise we'll have to get the actions so we can check
- * them. */
- if (udump->need_revalidate) {
- if (dpif_flow_get(udpif->dpif, ukey->key, ukey->key_len, &actions,
- &udump->stats)) {
- goto exit;
- }
- }
-
last_used = ukey->stats.used;
- push.used = udump->stats.used;
- push.tcp_flags = udump->stats.tcp_flags;
- push.n_packets = udump->stats.n_packets > ukey->stats.n_packets
- ? udump->stats.n_packets - ukey->stats.n_packets
+ push.used = stats->used;
+ push.tcp_flags = stats->tcp_flags;
+ push.n_packets = stats->n_packets > ukey->stats.n_packets
+ ? stats->n_packets - ukey->stats.n_packets
: 0;
- push.n_bytes = udump->stats.n_bytes > ukey->stats.n_bytes
- ? udump->stats.n_bytes - ukey->stats.n_bytes
+ push.n_bytes = stats->n_bytes > ukey->stats.n_bytes
+ ? stats->n_bytes - ukey->stats.n_bytes
: 0;
- ukey->stats = udump->stats;
- if (udump->need_revalidate && last_used
- && !should_revalidate(push.n_packets, last_used)) {
+ if (udpif->need_revalidate && last_used
+ && !should_revalidate(udpif, push.n_packets, last_used)) {
ok = false;
goto exit;
}
- if (!push.n_packets && !udump->need_revalidate) {
+ /* We will push the stats, so update the ukey stats cache. */
+ ukey->stats = *stats;
+ if (!push.n_packets && !udpif->need_revalidate) {
ok = true;
goto exit;
}
may_learn = push.n_packets > 0;
- if (ukey->xcache && !udump->need_revalidate) {
+ if (ukey->xcache && !udpif->need_revalidate) {
xlate_push_stats(ukey->xcache, may_learn, &push);
ok = true;
goto exit;
goto exit;
}
- if (udump->need_revalidate) {
+ if (udpif->need_revalidate) {
xlate_cache_clear(ukey->xcache);
}
if (!ukey->xcache) {
xin.resubmit_stats = push.n_packets ? &push : NULL;
xin.xcache = ukey->xcache;
xin.may_learn = may_learn;
- xin.skip_wildcards = !udump->need_revalidate;
+ xin.skip_wildcards = !udpif->need_revalidate;
xlate_actions(&xin, &xout);
xoutp = &xout;
- if (!udump->need_revalidate) {
+ if (!udpif->need_revalidate) {
ok = true;
goto exit;
}
compose_slow_path(udpif, &xout, &flow, odp_in_port, &xout_actions);
}
- if (!ofpbuf_equal(&xout_actions, actions)) {
+ if (actions_len != ofpbuf_size(&xout_actions)
+ || memcmp(ofpbuf_data(&xout_actions), actions, actions_len)) {
goto exit;
}
- if (odp_flow_key_to_mask(udump->mask, udump->mask_len, &udump_mask, &flow)
+ if (odp_flow_key_to_mask(mask, mask_len, &dp_mask, &flow)
== ODP_FIT_ERROR) {
goto exit;
}
* mask in the kernel is more specific i.e. less wildcarded, than what
* we've calculated here. This guarantees we don't catch any packets we
* shouldn't with the megaflow. */
- udump32 = (uint32_t *) &udump_mask;
+ dp32 = (uint32_t *) &dp_mask;
xout32 = (uint32_t *) &xout.wc.masks;
for (i = 0; i < FLOW_U32S; i++) {
- if ((udump32[i] | xout32[i]) != udump32[i]) {
+ if ((dp32[i] | xout32[i]) != dp32[i]) {
goto exit;
}
}
exit:
if (netflow) {
if (!ok) {
- netflow_expire(netflow, &flow);
netflow_flow_clear(netflow, &flow);
}
netflow_unref(netflow);
}
- ofpbuf_delete(actions);
xlate_out_uninit(xoutp);
return ok;
}
struct dump_op {
struct udpif_key *ukey;
- struct udpif_flow_dump *udump;
struct dpif_flow_stats stats; /* Stats for 'op'. */
struct dpif_op op; /* Flow del operation. */
};
static void
dump_op_init(struct dump_op *op, const struct nlattr *key, size_t key_len,
- struct udpif_key *ukey, struct udpif_flow_dump *udump)
+ struct udpif_key *ukey)
{
op->ukey = ukey;
- op->udump = udump;
op->op.type = DPIF_OP_FLOW_DEL;
op->op.u.flow_del.key = key;
op->op.u.flow_del.key_len = key_len;
}
static void
-push_dump_ops(struct revalidator *revalidator,
- struct dump_op *ops, size_t n_ops)
+push_dump_ops__(struct udpif *udpif, struct dump_op *ops, size_t n_ops)
{
- struct udpif *udpif = revalidator->udpif;
struct dpif_op *opsp[REVALIDATE_MAX_BATCH];
size_t i;
stats = op->op.u.flow_del.stats;
if (op->ukey) {
push = &push_buf;
+ ovs_mutex_lock(&op->ukey->mutex);
push->used = MAX(stats->used, op->ukey->stats.used);
push->tcp_flags = stats->tcp_flags | op->ukey->stats.tcp_flags;
push->n_packets = stats->n_packets - op->ukey->stats.n_packets;
push->n_bytes = stats->n_bytes - op->ukey->stats.n_bytes;
+ ovs_mutex_unlock(&op->ukey->mutex);
} else {
push = stats;
}
bool may_learn;
may_learn = push->n_packets > 0;
- if (op->ukey && op->ukey->xcache) {
- xlate_push_stats(op->ukey->xcache, may_learn, push);
- continue;
+ if (op->ukey) {
+ ovs_mutex_lock(&op->ukey->mutex);
+ if (op->ukey->xcache) {
+ xlate_push_stats(op->ukey->xcache, may_learn, push);
+ ovs_mutex_unlock(&op->ukey->mutex);
+ continue;
+ }
+ ovs_mutex_unlock(&op->ukey->mutex);
}
if (!xlate_receive(udpif->backer, NULL, op->op.u.flow_del.key,
xlate_actions_for_side_effects(&xin);
if (netflow) {
- netflow_expire(netflow, &flow);
netflow_flow_clear(netflow, &flow);
netflow_unref(netflow);
}
}
}
}
+}
- for (i = 0; i < n_ops; i++) {
- struct udpif_key *ukey;
+static void
+push_dump_ops(struct revalidator *revalidator,
+ struct dump_op *ops, size_t n_ops)
+{
+ int i;
- /* If there's a udump, this ukey came directly from a datapath flow
- * dump. Sometimes a datapath can send duplicates in flow dumps, in
- * which case we wouldn't want to double-free a ukey, so avoid that by
- * looking up the ukey again.
- *
- * If there's no udump then we know what we're doing. */
- ukey = (ops[i].udump
- ? ukey_lookup(revalidator, ops[i].udump)
- : ops[i].ukey);
- if (ukey) {
- ukey_delete(revalidator, ukey);
- }
+ push_dump_ops__(revalidator->udpif, ops, n_ops);
+ for (i = 0; i < n_ops; i++) {
+ ukey_delete(revalidator, ops[i].ukey);
}
}
static void
-revalidate_udumps(struct revalidator *revalidator, struct list *udumps)
+revalidate(struct revalidator *revalidator)
{
struct udpif *udpif = revalidator->udpif;
struct dump_op ops[REVALIDATE_MAX_BATCH];
- struct udpif_flow_dump *udump, *next_udump;
- size_t n_ops, n_flows;
+ const struct nlattr *key, *mask, *actions;
+ size_t key_len, mask_len, actions_len;
+ const struct dpif_flow_stats *stats;
+ long long int now;
unsigned int flow_limit;
- long long int max_idle;
- bool must_del;
+ size_t n_ops;
+ void *state;
+ n_ops = 0;
+ now = time_msec();
atomic_read(&udpif->flow_limit, &flow_limit);
- n_flows = udpif_get_n_flows(udpif);
+ dpif_flow_dump_state_init(udpif->dpif, &state);
+ while (dpif_flow_dump_next(&udpif->dump, state, &key, &key_len, &mask,
+ &mask_len, &actions, &actions_len, &stats)) {
+ struct udpif_key *ukey;
+ bool mark, may_destroy;
+ long long int used, max_idle;
+ uint32_t hash;
+ size_t n_flows;
+
+ hash = hash_bytes(key, key_len, udpif->secret);
+ ukey = ukey_lookup(udpif, key, key_len, hash);
- must_del = false;
- max_idle = ofproto_max_idle;
- if (n_flows > flow_limit) {
- must_del = n_flows > 2 * flow_limit;
- max_idle = 100;
- }
+ used = stats->used;
+ if (!ukey) {
+ ukey = ukey_create(key, key_len, used);
+ if (!udpif_insert_ukey(udpif, ukey, hash)) {
+ /* The same ukey has already been created. This means that
+ * another revalidator is processing this flow
+ * concurrently, so don't bother processing it. */
+ COVERAGE_INC(upcall_duplicate_flow);
+ ukey_delete(NULL, ukey);
+ goto next;
+ }
+ }
- n_ops = 0;
- LIST_FOR_EACH_SAFE (udump, next_udump, list_node, udumps) {
- long long int used, now;
- struct udpif_key *ukey;
+ if (ovs_mutex_trylock(&ukey->mutex)) {
+ /* The flow has been dumped, and is being handled by another
+ * revalidator concurrently. This can occasionally occur if the
+ * datapath is changed in the middle of a flow dump. Rather than
+ * perform the same work twice, skip the flow this time. */
+ COVERAGE_INC(upcall_duplicate_flow);
+ goto next;
+ }
- now = time_msec();
- ukey = ukey_lookup(revalidator, udump);
+ if (ukey->mark || !ukey->flow_exists) {
+ /* The flow has already been dumped and handled by another
+ * revalidator during this flow dump operation. Skip it. */
+ COVERAGE_INC(upcall_duplicate_flow);
+ ovs_mutex_unlock(&ukey->mutex);
+ goto next;
+ }
- used = udump->stats.used;
- if (!used && ukey) {
+ if (!used) {
used = ukey->created;
}
+ n_flows = udpif_get_n_flows(udpif);
+ max_idle = ofproto_max_idle;
+ if (n_flows > flow_limit) {
+ max_idle = 100;
+ }
- if (must_del || (used && used < now - max_idle)) {
- struct dump_op *dop = &ops[n_ops++];
+ if ((used && used < now - max_idle) || n_flows > flow_limit * 2) {
+ mark = false;
+ } else {
+ mark = revalidate_ukey(udpif, ukey, mask, mask_len, actions,
+ actions_len, stats);
+ }
+ ukey->mark = ukey->flow_exists = mark;
- dump_op_init(dop, udump->key, udump->key_len, ukey, udump);
- continue;
+ if (!mark) {
+ dump_op_init(&ops[n_ops++], key, key_len, ukey);
}
+ ovs_mutex_unlock(&ukey->mutex);
- if (!ukey) {
- ukey = ukey_create(udump->key, udump->key_len, used);
- hmap_insert(&revalidator->ukeys, &ukey->hmap_node,
- udump->key_hash);
+ next:
+ may_destroy = dpif_flow_dump_next_may_destroy_keys(&udpif->dump,
+ state);
+
+ /* Only update 'now' immediately before 'buffer' will be updated.
+ * This gives us the current time relative to the time the datapath
+ * will write into 'stats'. */
+ if (may_destroy) {
+ now = time_msec();
}
- ukey->mark = true;
- if (!revalidate_ukey(udpif, udump, ukey)) {
- dpif_flow_del(udpif->dpif, udump->key, udump->key_len, NULL);
- ukey_delete(revalidator, ukey);
+ /* Only do a dpif_operate when we've hit our maximum batch, or when our
+ * memory is about to be clobbered by the next call to
+ * dpif_flow_dump_next(). */
+ if (n_ops == REVALIDATE_MAX_BATCH || (n_ops && may_destroy)) {
+ push_dump_ops__(udpif, ops, n_ops);
+ n_ops = 0;
}
+ }
- list_remove(&udump->list_node);
- free(udump);
+ if (n_ops) {
+ push_dump_ops__(udpif, ops, n_ops);
}
- push_dump_ops(revalidator, ops, n_ops);
+ dpif_flow_dump_state_uninit(udpif->dpif, state);
+}
- LIST_FOR_EACH_SAFE (udump, next_udump, list_node, udumps) {
- list_remove(&udump->list_node);
- free(udump);
+/* Called with exclusive access to 'revalidator' and 'ukey'. */
+static bool
+handle_missed_revalidation(struct revalidator *revalidator,
+ struct udpif_key *ukey)
+ OVS_NO_THREAD_SAFETY_ANALYSIS
+{
+ struct udpif *udpif = revalidator->udpif;
+ struct nlattr *mask, *actions;
+ size_t mask_len, actions_len;
+ struct dpif_flow_stats stats;
+ struct ofpbuf *buf;
+ bool keep = false;
+
+ COVERAGE_INC(revalidate_missed_dp_flow);
+
+ if (!dpif_flow_get(udpif->dpif, ukey->key, ukey->key_len, &buf,
+ &mask, &mask_len, &actions, &actions_len, &stats)) {
+ keep = revalidate_ukey(udpif, ukey, mask, mask_len, actions,
+ actions_len, &stats);
+ ofpbuf_delete(buf);
}
+
+ return keep;
}
static void
revalidator_sweep__(struct revalidator *revalidator, bool purge)
+ OVS_NO_THREAD_SAFETY_ANALYSIS
{
struct dump_op ops[REVALIDATE_MAX_BATCH];
struct udpif_key *ukey, *next;
n_ops = 0;
- HMAP_FOR_EACH_SAFE (ukey, next, hmap_node, &revalidator->ukeys) {
- if (!purge && ukey->mark) {
+ /* During garbage collection, this revalidator completely owns its ukeys
+ * map, and therefore doesn't need to do any locking. */
+ HMAP_FOR_EACH_SAFE (ukey, next, hmap_node, revalidator->ukeys) {
+ if (ukey->flow_exists) {
+ bool missed_flow = !ukey->mark;
+
ukey->mark = false;
- } else {
- struct dump_op *op = &ops[n_ops++];
-
- /* If we have previously seen a flow in the datapath, but didn't
- * see it during the most recent dump, delete it. This allows us
- * to clean up the ukey and keep the statistics consistent. */
- dump_op_init(op, ukey->key, ukey->key_len, ukey, NULL);
- if (n_ops == REVALIDATE_MAX_BATCH) {
- push_dump_ops(revalidator, ops, n_ops);
- n_ops = 0;
+ if (purge
+ || (missed_flow
+ && revalidator->udpif->need_revalidate
+ && !handle_missed_revalidation(revalidator, ukey))) {
+ struct dump_op *op = &ops[n_ops++];
+
+ dump_op_init(op, ukey->key, ukey->key_len, ukey);
+ if (n_ops == REVALIDATE_MAX_BATCH) {
+ push_dump_ops(revalidator, ops, n_ops);
+ n_ops = 0;
+ }
}
+ } else {
+ ukey_delete(revalidator, ukey);
}
}
atomic_read(&udpif->flow_limit, &flow_limit);
ds_put_format(&ds, "%s:\n", dpif_name(udpif->dpif));
- ds_put_format(&ds, "\tflows : (current %"PRIu64")"
+ ds_put_format(&ds, "\tflows : (current %lu)"
" (avg %u) (max %u) (limit %u)\n", udpif_get_n_flows(udpif),
udpif->avg_n_flows, udpif->max_n_flows, flow_limit);
ds_put_format(&ds, "\tdump duration : %lldms\n", udpif->dump_duration);
for (i = 0; i < n_revalidators; i++) {
struct revalidator *revalidator = &udpif->revalidators[i];
- /* XXX: The result of hmap_count(&revalidator->ukeys) may not be
- * accurate because it's not protected by the revalidator mutex. */
- ovs_mutex_lock(&revalidator->mutex);
- ds_put_format(&ds, "\t%s: (dump queue %"PRIuSIZE") (keys %"PRIuSIZE
- ")\n", revalidator->name, revalidator->n_udumps,
- hmap_count(&revalidator->ukeys));
- ovs_mutex_unlock(&revalidator->mutex);
+ ovs_mutex_lock(&udpif->ukeys[i].mutex);
+ ds_put_format(&ds, "\t%u: (keys %"PRIuSIZE")\n",
+ revalidator->id, hmap_count(&udpif->ukeys[i].hmap));
+ ovs_mutex_unlock(&udpif->ukeys[i].mutex);
}
}