xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/aggsum.h (revision 3a2d8a1b18794077eff4c504197c1d6f9d7ee487)
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  * Copyright (c) 2017 by Delphix. All rights reserved.
17  */
18 
19 #ifndef	_SYS_AGGSUM_H
20 #define	_SYS_AGGSUM_H
21 
22 #include <sys/zfs_context.h>
23 
24 #ifdef	__cplusplus
25 extern "C" {
26 #endif
27 
28 #define	CACHE_LINE_SIZE	64
29 
30 typedef struct aggsum_bucket {
31 	kmutex_t asc_lock;
32 	int64_t asc_delta;
33 	uint64_t asc_borrowed;
34 	uint64_t asc_pad[4]; /* pad out to cache line (64 bytes) */
35 } aggsum_bucket_t __aligned(CACHE_LINE_SIZE);
36 
37 /*
38  * Fan out over FANOUT cpus.
39  */
40 typedef struct aggsum {
41 	kmutex_t as_lock;
42 	int64_t as_lower_bound;
43 	int64_t as_upper_bound;
44 	uint64_t as_numbuckets;
45 	aggsum_bucket_t *as_buckets;
46 } aggsum_t;
47 
48 void aggsum_init(aggsum_t *, uint64_t);
49 void aggsum_fini(aggsum_t *);
50 int64_t aggsum_lower_bound(aggsum_t *);
51 int64_t aggsum_upper_bound(aggsum_t *);
52 int aggsum_compare(aggsum_t *, uint64_t);
53 uint64_t aggsum_value(aggsum_t *);
54 void aggsum_add(aggsum_t *, int64_t);
55 
56 #ifdef	__cplusplus
57 }
58 #endif
59 
60 #endif /* _SYS_AGGSUM_H */
61