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+/*
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * counter.h: simple and packet/byte counters
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef included_vlib_counter_h
+#define included_vlib_counter_h
+
+/** \file
+
+ Optimized thread-safe counters.
+
+ Each vlib_[simple|combined]_counter_main_t consists of a single
+ vector of thread-safe / atomically-updated u64 counters [the
+ "maxi" vector], and a (u16 **) per-thread vector [the "minis"
+ vector] of narrow, per-thread counters.
+
+ The idea is to drastically reduce the number of atomic operations.
+ In the case of packet counts, we divide the number of atomic ops
+ by 2**16, etc.
+*/
+
+/** A collection of simple counters */
+
+typedef struct
+{
+ u16 **minis; /**< Per-thread u16 non-atomic counters */
+ u64 *maxi; /**< Shared wide counters */
+ u64 *value_at_last_clear; /**< Counter values as of last clear. */
+ u64 *value_at_last_serialize; /**< Values as of last serialize. */
+ u32 last_incremental_serialize_index; /**< Last counter index
+ serialized incrementally. */
+
+ char *name; /**< The counter collection's name. */
+} vlib_simple_counter_main_t;
+
+/** Increment a simple counter
+ @param cm - (vlib_simple_counter_main_t *) simple counter main pointer
+ @param cpu_index - (u32) the current cpu index
+ @param index - (u32) index of the counter to increment
+ @param increment - (u32) quantitiy to add to the counter
+*/
+always_inline void
+vlib_increment_simple_counter (vlib_simple_counter_main_t * cm,
+ u32 cpu_index, u32 index, u32 increment)
+{
+ u16 *my_minis;
+ u16 *mini;
+ u32 old, new;
+
+ my_minis = cm->minis[cpu_index];
+ mini = vec_elt_at_index (my_minis, index);
+ old = mini[0];
+ new = old + increment;
+ mini[0] = new;
+
+ if (PREDICT_FALSE (mini[0] != new))
+ {
+ __sync_fetch_and_add (&cm->maxi[index], new);
+ my_minis[index] = 0;
+ }
+}
+
+/** Get the value of a simple counter
+ Scrapes the entire set of mini counters. Innacurate unless
+ worker threads which might increment the counter are
+ barrier-synchronized
+
+ @param cm - (vlib_simple_counter_main_t *) simple counter main pointer
+ @param index - (u32) index of the counter to fetch
+ @returns - (u64) current counter value
+*/
+always_inline u64
+vlib_get_simple_counter (vlib_simple_counter_main_t * cm, u32 index)
+{
+ u16 *my_minis, *mini;
+ u64 v;
+ int i;
+
+ ASSERT (index < vec_len (cm->maxi));
+
+ v = 0;
+
+ for (i = 0; i < vec_len (cm->minis); i++)
+ {
+ my_minis = cm->minis[i];
+ mini = vec_elt_at_index (my_minis, index);
+ v += mini[0];
+ }
+
+ v += cm->maxi[index];
+
+ if (index < vec_len (cm->value_at_last_clear))
+ {
+ ASSERT (v >= cm->value_at_last_clear[index]);
+ v -= cm->value_at_last_clear[index];
+ }
+
+ return v;
+}
+
+/** Clear a simple counter
+ Clears the set of per-thread u16 counters, and the u64 counter
+
+ @param cm - (vlib_simple_counter_main_t *) simple counter main pointer
+ @param index - (u32) index of the counter to clear
+*/
+always_inline void
+vlib_zero_simple_counter (vlib_simple_counter_main_t * cm, u32 index)
+{
+ u16 *my_minis;
+ int i;
+
+ ASSERT (index < vec_len (cm->maxi));
+
+ for (i = 0; i < vec_len (cm->minis); i++)
+ {
+ my_minis = cm->minis[i];
+ my_minis[index] = 0;
+ }
+
+ cm->maxi[index] = 0;
+
+ if (index < vec_len (cm->value_at_last_clear))
+ cm->value_at_last_clear[index] = 0;
+}
+
+/** Combined counter to hold both packets and byte differences.
+ */
+typedef struct
+{
+ u64 packets; /**< packet counter */
+ u64 bytes; /**< byte counter */
+} vlib_counter_t;
+
+/** Add two combined counters, results in the first counter
+ @param [in,out] a - (vlib_counter_t *) dst counter
+ @param b - (vlib_counter_t *) src counter
+*/
+
+always_inline void
+vlib_counter_add (vlib_counter_t * a, vlib_counter_t * b)
+{
+ a->packets += b->packets;
+ a->bytes += b->bytes;
+}
+
+/** Subtract combined counters, results in the first counter
+ @param [in,out] a - (vlib_counter_t *) dst counter
+ @param b - (vlib_counter_t *) src counter
+*/
+always_inline void
+vlib_counter_sub (vlib_counter_t * a, vlib_counter_t * b)
+{
+ ASSERT (a->packets >= b->packets);
+ ASSERT (a->bytes >= b->bytes);
+ a->packets -= b->packets;
+ a->bytes -= b->bytes;
+}
+
+/** Clear a combined counter
+ @param a - (vlib_counter_t *) counter to clear
+*/
+always_inline void
+vlib_counter_zero (vlib_counter_t * a)
+{
+ a->packets = a->bytes = 0;
+}
+
+/** Mini combined counter */
+typedef struct
+{
+ u16 packets; /**< Packet count */
+ i16 bytes; /**< Byte count */
+} vlib_mini_counter_t;
+
+/** A collection of combined counters */
+typedef struct
+{
+ vlib_mini_counter_t **minis; /**< Per-thread u16 non-atomic counter pairs */
+ vlib_counter_t *maxi; /**< Shared wide counter pairs */
+ vlib_counter_t *value_at_last_clear; /**< Counter values as of last clear. */
+ vlib_counter_t *value_at_last_serialize; /**< Counter values as of last serialize. */
+ u32 last_incremental_serialize_index; /**< Last counter index serialized incrementally. */
+ char *name; /**< The counter collection's name. */
+} vlib_combined_counter_main_t;
+
+/** Clear a collection of simple counters
+ @param cm - (vlib_simple_counter_main_t *) collection to clear
+*/
+void vlib_clear_simple_counters (vlib_simple_counter_main_t * cm);
+
+/** Clear a collection of combined counters
+ @param cm - (vlib_combined_counter_main_t *) collection to clear
+*/
+void vlib_clear_combined_counters (vlib_combined_counter_main_t * cm);
+
+/** Increment a combined counter
+ @param cm - (vlib_combined_counter_main_t *) comined counter main pointer
+ @param cpu_index - (u32) the current cpu index
+ @param index - (u32) index of the counter to increment
+ @param packet_increment - (u32) number of packets to add to the counter
+ @param byte_increment - (u32) number of bytes to add to the counter
+*/
+
+always_inline void
+vlib_increment_combined_counter (vlib_combined_counter_main_t * cm,
+ u32 cpu_index,
+ u32 index,
+ u32 packet_increment, u32 byte_increment)
+{
+ vlib_mini_counter_t *my_minis, *mini;
+ u32 old_packets, new_packets;
+ i32 old_bytes, new_bytes;
+
+ /* Use this CPU's mini counter array */
+ my_minis = cm->minis[cpu_index];
+
+ mini = vec_elt_at_index (my_minis, index);
+ old_packets = mini->packets;
+ old_bytes = mini->bytes;
+
+ new_packets = old_packets + packet_increment;
+ new_bytes = old_bytes + byte_increment;
+
+ mini->packets = new_packets;
+ mini->bytes = new_bytes;
+
+ /* Bytes always overflow before packets.. */
+ if (PREDICT_FALSE (mini->bytes != new_bytes))
+ {
+ vlib_counter_t *maxi = vec_elt_at_index (cm->maxi, index);
+
+ __sync_fetch_and_add (&maxi->packets, new_packets);
+ __sync_fetch_and_add (&maxi->bytes, new_bytes);
+
+ mini->packets = 0;
+ mini->bytes = 0;
+ }
+}
+
+/** Get the value of a combined counter, never called in the speed path
+ Scrapes the entire set of mini counters. Innacurate unless
+ worker threads which might increment the counter are
+ barrier-synchronized
+
+ @param cm - (vlib_combined_counter_main_t *) combined counter main pointer
+ @param index - (u32) index of the combined counter to fetch
+ @param result [out] - (vlib_counter_t *) result stored here
+*/
+
+static inline void
+vlib_get_combined_counter (vlib_combined_counter_main_t * cm,
+ u32 index, vlib_counter_t * result)
+{
+ vlib_mini_counter_t *my_minis, *mini;
+ vlib_counter_t *maxi;
+ int i;
+
+ result->packets = 0;
+ result->bytes = 0;
+
+ for (i = 0; i < vec_len (cm->minis); i++)
+ {
+ my_minis = cm->minis[i];
+
+ mini = vec_elt_at_index (my_minis, index);
+ result->packets += mini->packets;
+ result->bytes += mini->bytes;
+ }
+
+ maxi = vec_elt_at_index (cm->maxi, index);
+ result->packets += maxi->packets;
+ result->bytes += maxi->bytes;
+
+ if (index < vec_len (cm->value_at_last_clear))
+ vlib_counter_sub (result, &cm->value_at_last_clear[index]);
+}
+
+/** Clear a combined counter
+ Clears the set of per-thread u16 counters, and the shared vlib_counter_t
+
+ @param cm - (vlib_combined_counter_main_t *) combined counter main pointer
+ @param index - (u32) index of the counter to clear
+*/
+always_inline void
+vlib_zero_combined_counter (vlib_combined_counter_main_t * cm, u32 index)
+{
+ vlib_mini_counter_t *mini, *my_minis;
+ int i;
+
+ for (i = 0; i < vec_len (cm->minis); i++)
+ {
+ my_minis = cm->minis[i];
+
+ mini = vec_elt_at_index (my_minis, index);
+ mini->packets = 0;
+ mini->bytes = 0;
+ }
+
+ vlib_counter_zero (&cm->maxi[index]);
+ if (index < vec_len (cm->value_at_last_clear))
+ vlib_counter_zero (&cm->value_at_last_clear[index]);
+}
+
+/** validate a simple counter
+ @param cm - (vlib_simple_counter_main_t *) pointer to the counter collection
+ @param index - (u32) index of the counter to validate
+*/
+
+void vlib_validate_simple_counter (vlib_simple_counter_main_t * cm,
+ u32 index);
+/** validate a combined counter
+ @param cm - (vlib_combined_counter_main_t *) pointer to the counter
+ collection
+ @param index - (u32) index of the counter to validate
+*/
+
+void vlib_validate_combined_counter (vlib_combined_counter_main_t * cm,
+ u32 index);
+
+/** Obtain the number of simple or combined counters allocated.
+ A macro which reduces to to vec_len(cm->maxi), the answer in either
+ case.
+
+ @param cm - (vlib_simple_counter_main_t) or
+ (vlib_combined_counter_main_t) the counter collection to interrogate
+ @returns vec_len(cm->maxi)
+*/
+#define vlib_counter_len(cm) vec_len((cm)->maxi)
+
+serialize_function_t serialize_vlib_simple_counter_main,
+ unserialize_vlib_simple_counter_main;
+serialize_function_t serialize_vlib_combined_counter_main,
+ unserialize_vlib_combined_counter_main;
+
+#endif /* included_vlib_counter_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */