diff options
Diffstat (limited to 'src/vlib/counter.h')
-rw-r--r-- | src/vlib/counter.h | 207 |
1 files changed, 72 insertions, 135 deletions
diff --git a/src/vlib/counter.h b/src/vlib/counter.h index abfa89eea6d..17a8521776b 100644 --- a/src/vlib/counter.h +++ b/src/vlib/counter.h @@ -44,59 +44,48 @@ 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. + Each vlib_[simple|combined]_counter_main_t consists of a per-thread + vector of per-object counters. + + The idea is to drastically eliminate atomic operations. */ +/** 64bit counters */ +typedef u64 counter_t; + /** 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. */ + counter_t **counters; /**< Per-thread u64 non-atomic counters */ + counter_t *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; +/** The number of counters (not the number of per-thread counters) */ +u32 vlib_simple_counter_n_counters (const vlib_simple_counter_main_t * cm); + /** 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 + @param increment - (u64) 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) + u32 cpu_index, u32 index, u64 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; + counter_t *my_counters; - if (PREDICT_FALSE (mini[0] != new)) - { - __sync_fetch_and_add (&cm->maxi[index], new); - my_minis[index] = 0; - } + my_counters = cm->counters[cpu_index]; + my_counters[index] += increment; } /** Get the value of a simple counter - Scrapes the entire set of mini counters. Innacurate unless + Scrapes the entire set of per-thread counters. Innacurate unless worker threads which might increment the counter are barrier-synchronized @@ -104,30 +93,21 @@ vlib_increment_simple_counter (vlib_simple_counter_main_t * cm, @param index - (u32) index of the counter to fetch @returns - (u64) current counter value */ -always_inline u64 +always_inline counter_t vlib_get_simple_counter (vlib_simple_counter_main_t * cm, u32 index) { - u16 *my_minis, *mini; - u64 v; + counter_t *my_counters; + counter_t v; int i; - ASSERT (index < vec_len (cm->maxi)); + ASSERT (index < vlib_simple_counter_n_counters (cm)); v = 0; - for (i = 0; i < vec_len (cm->minis); i++) + for (i = 0; i < vec_len (cm->counters); 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]; + my_counters = cm->counters[i]; + v += my_counters[index]; } return v; @@ -142,29 +122,24 @@ vlib_get_simple_counter (vlib_simple_counter_main_t * cm, u32 index) always_inline void vlib_zero_simple_counter (vlib_simple_counter_main_t * cm, u32 index) { - u16 *my_minis; + counter_t *my_counters; int i; - ASSERT (index < vec_len (cm->maxi)); + ASSERT (index < vlib_simple_counter_n_counters (cm)); - for (i = 0; i < vec_len (cm->minis); i++) + for (i = 0; i < vec_len (cm->counters); i++) { - my_minis = cm->minis[i]; - my_minis[index] = 0; + my_counters = cm->counters[i]; + my_counters[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 */ + counter_t packets; /**< packet counter */ + counter_t bytes; /**< byte counter */ } vlib_counter_t; /** Add two combined counters, results in the first counter @@ -201,24 +176,19 @@ 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 **counters; /**< Per-thread u64 non-atomic counter pairs */ 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; +/** The number of counters (not the number of per-thread counters) */ +u32 vlib_combined_counter_n_counters (const vlib_combined_counter_main_t * + cm); + /** Clear a collection of simple counters @param cm - (vlib_simple_counter_main_t *) collection to clear */ @@ -233,62 +203,41 @@ void vlib_clear_combined_counters (vlib_combined_counter_main_t * cm); @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 + @param packet_increment - (u64) number of packets to add to the counter + @param byte_increment - (u64) 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) + u32 index, u64 n_packets, u64 n_bytes) { - 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); + vlib_counter_t *my_counters; - __sync_fetch_and_add (&maxi->packets, new_packets); - __sync_fetch_and_add (&maxi->bytes, new_bytes); + /* Use this CPU's counter array */ + my_counters = cm->counters[cpu_index]; - mini->packets = 0; - mini->bytes = 0; - } + my_counters[index].packets += n_packets; + my_counters[index].bytes += n_bytes; } -#define vlib_prefetch_combined_counter(_cm, _cpu_index, _index) \ -{ \ - vlib_mini_counter_t *_cpu_minis; \ - \ - /* \ - * This CPU's mini index is assumed to already be in cache \ - */ \ - _cpu_minis = (_cm)->minis[(_cpu_index)]; \ - CLIB_PREFETCH(_cpu_minis + (_index), \ - sizeof(*_cpu_minis), \ - STORE); \ +/** Pre-fetch a per-thread combined counter for the given object index */ +always_inline void +vlib_prefetch_combined_counter (const vlib_combined_counter_main_t * cm, + u32 cpu_index, u32 index) +{ + vlib_counter_t *cpu_counters; + + /* + * This CPU's index is assumed to already be in cache + */ + cpu_counters = cm->counters[cpu_index]; + CLIB_PREFETCH (cpu_counters + index, CLIB_CACHE_LINE_BYTES, STORE); } /** Get the value of a combined counter, never called in the speed path - Scrapes the entire set of mini counters. Innacurate unless + Scrapes the entire set of per-thread counters. Innacurate unless worker threads which might increment the counter are barrier-synchronized @@ -298,35 +247,27 @@ vlib_increment_combined_counter (vlib_combined_counter_main_t * cm, */ static inline void -vlib_get_combined_counter (vlib_combined_counter_main_t * cm, +vlib_get_combined_counter (const vlib_combined_counter_main_t * cm, u32 index, vlib_counter_t * result) { - vlib_mini_counter_t *my_minis, *mini; - vlib_counter_t *maxi; + vlib_counter_t *my_counters, *counter; int i; result->packets = 0; result->bytes = 0; - for (i = 0; i < vec_len (cm->minis); i++) + for (i = 0; i < vec_len (cm->counters); i++) { - my_minis = cm->minis[i]; + my_counters = cm->counters[i]; - mini = vec_elt_at_index (my_minis, index); - result->packets += mini->packets; - result->bytes += mini->bytes; + counter = vec_elt_at_index (my_counters, index); + result->packets += counter->packets; + result->bytes += counter->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 + Clears the set of per-thread counters. @param cm - (vlib_combined_counter_main_t *) combined counter main pointer @param index - (u32) index of the counter to clear @@ -334,21 +275,17 @@ vlib_get_combined_counter (vlib_combined_counter_main_t * cm, always_inline void vlib_zero_combined_counter (vlib_combined_counter_main_t * cm, u32 index) { - vlib_mini_counter_t *mini, *my_minis; + vlib_counter_t *my_counters, *counter; int i; - for (i = 0; i < vec_len (cm->minis); i++) + for (i = 0; i < vec_len (cm->counters); i++) { - my_minis = cm->minis[i]; + my_counters = cm->counters[i]; - mini = vec_elt_at_index (my_minis, index); - mini->packets = 0; - mini->bytes = 0; + counter = vec_elt_at_index (my_counters, index); + counter->packets = 0; + counter->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 |