1 /* 2 * CDDL HEADER START 3 * 4 * This file and its contents are supplied under the terms of the 5 * Common Development and Distribution License ("CDDL"), version 1.0. 6 * You may only use this file in accordance with the terms of version 7 * 1.0 of the CDDL. 8 * 9 * A full copy of the text of the CDDL should have accompanied this 10 * source. A copy of the CDDL is also available via the Internet at 11 * http://www.illumos.org/license/CDDL. 12 * 13 * CDDL HEADER END 14 */ 15 16 /* 17 * wmsum counters are a reduced version of aggsum counters, optimized for 18 * write-mostly scenarios. They do not provide optimized read functions, 19 * but instead allow much cheaper add function. The primary usage is 20 * infrequently read statistic counters, not requiring exact precision. 21 * 22 * The FreeBSD implementation is directly mapped into counter(9) KPI. 23 */ 24 25 #ifndef _SYS_WMSUM_H 26 #define _SYS_WMSUM_H 27 28 #include <sys/types.h> 29 #include <sys/systm.h> 30 #include <sys/counter.h> 31 #include <sys/malloc.h> 32 33 #ifdef __cplusplus 34 extern "C" { 35 #endif 36 37 #define wmsum_t counter_u64_t 38 39 static inline void 40 wmsum_init(wmsum_t *ws, uint64_t value) 41 { 42 43 *ws = counter_u64_alloc(M_WAITOK); 44 counter_u64_add(*ws, value); 45 } 46 47 static inline void 48 wmsum_fini(wmsum_t *ws) 49 { 50 51 counter_u64_free(*ws); 52 } 53 54 static inline uint64_t 55 wmsum_value(wmsum_t *ws) 56 { 57 58 return (counter_u64_fetch(*ws)); 59 } 60 61 static inline void 62 wmsum_add(wmsum_t *ws, int64_t delta) 63 { 64 65 counter_u64_add(*ws, delta); 66 } 67 68 #ifdef __cplusplus 69 } 70 #endif 71 72 #endif /* _SYS_WMSUM_H */ 73