1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #ifndef _SYS_CLOCK_IMPL_H 28 #define _SYS_CLOCK_IMPL_H 29 30 #ifdef __cplusplus 31 extern "C" { 32 #endif 33 34 #if (defined(_KERNEL) || defined(_KMEMUSER)) 35 #include <sys/types.h> 36 #include <sys/cpuvar.h> 37 #include <sys/cyclic.h> 38 #include <sys/time.h> 39 40 /* 41 * Default clock rate in Hz. 42 */ 43 #define HZ_DEFAULT 100 44 45 /* 46 * Thresholds over which we switch between event and cyclic driven lbolt. The 47 * current default values were derived experimentally and will keep the 48 * system on event driven mode when idle and respond to activity around the 49 * lbolt DDI functions by switching to cyclic mode. 50 */ 51 #define LBOLT_THRESH_CALLS (75) 52 #define LBOLT_THRESH_INTERVAL (1) 53 54 /* 55 * Both lbolt_cpu_t and lbolt_info_t are cache line sized and aligned, 56 * please take that in consideration if modifying these. 57 */ 58 typedef struct lbolt_cpu { 59 int64_t lbc_counter; /* number of calls to the DDI lbolt routines */ 60 int64_t lbc_cnt_start; /* beggining of the cnt interval (in ticks) */ 61 char lbc_pad[CPU_CACHE_COHERENCE_SIZE - (2 * sizeof (int64_t))]; 62 } lbolt_cpu_t; 63 64 typedef struct lbolt_info { 65 cyclic_id_t lbi_cyclic_id; /* lbolt's cyclic id */ 66 int64_t lbi_internal; /* lbolt source when on cyclic mode */ 67 int64_t lbi_debug_time; /* time spent in the debugger */ 68 int64_t lbi_debug_ts; /* last time we dropped into kmdb */ 69 int64_t lbi_thresh_calls; /* max calls per interval */ 70 int64_t lbi_thresh_interval; /* interval window for the # of calls */ 71 uint32_t lbi_token; /* synchronize cyclic mode switch */ 72 boolean_t lbi_cyc_deactivate; /* lbolt_cyclic self deactivation */ 73 int64_t lbi_cyc_deac_start; /* deactivation interval */ 74 } lbolt_info_t; 75 76 extern int64_t lbolt_event_driven(void); 77 extern int64_t lbolt_cyclic_driven(void); 78 extern int64_t (*lbolt_hybrid)(void); 79 extern uint_t lbolt_ev_to_cyclic(caddr_t, caddr_t); 80 81 extern void lbolt_softint_add(void); 82 extern void lbolt_softint_post(void); 83 84 extern void lbolt_debug_entry(void); 85 extern void lbolt_debug_return(void); 86 87 extern lbolt_info_t *lb_info; 88 89 /* 90 * LBOLT_WAITFREE provides a non-waiting version of lbolt. 91 */ 92 #define LBOLT_WAITFREE \ 93 (lbolt_hybrid == lbolt_event_driven ? \ 94 ((gethrtime_waitfree()/nsec_per_tick) - \ 95 lb_info->lbi_debug_time) : \ 96 (lb_info->lbi_internal - lb_info->lbi_debug_time)) 97 98 /* 99 * LBOLT_FASTPATH should *only* be used where the cost of calling 100 * ddi_get_lbolt() affects performance. This is currently only used by the 101 * TCP/IP code and will be removed once it's no longer required. 102 */ 103 #define LBOLT_FASTPATH \ 104 (lbolt_hybrid == lbolt_event_driven ? ddi_get_lbolt() : \ 105 (clock_t)(lb_info->lbi_internal - lb_info->lbi_debug_time)) 106 107 /* 108 * LBOLT_NO_ACCOUNT is used by lbolt consumers who fire at a periodic rate, 109 * such as clock(), for which the lbolt usage statistics are not updated. 110 * This is specially important for consumers whose rate may be modified by 111 * the user, resulting in an unaccounted for increase in activity around the 112 * lbolt routines that could cause a mode switch. 113 */ 114 #define LBOLT_NO_ACCOUNT \ 115 (lbolt_hybrid == lbolt_event_driven ? \ 116 ((gethrtime()/nsec_per_tick) - lb_info->lbi_debug_time) : \ 117 (lb_info->lbi_internal - lb_info->lbi_debug_time)) 118 119 #endif /* _KERNEL || _KMEMUSER */ 120 121 #ifdef __cplusplus 122 } 123 #endif 124 125 #endif /* _SYS_CLOCK_IMPL_H */ 126