diff options
author | jhb <jhb@FreeBSD.org> | 2000-10-20 07:26:37 +0000 |
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committer | jhb <jhb@FreeBSD.org> | 2000-10-20 07:26:37 +0000 |
commit | f671832d7667351a66ab594f63d8cd4ef66e8e91 (patch) | |
tree | 99efa7c13c407257b68406e364261eeb1b2c1972 /sys/alpha | |
parent | 787712af1c7ffb2642f8250f2111301ad77fdaf8 (diff) | |
download | FreeBSD-src-f671832d7667351a66ab594f63d8cd4ef66e8e91.zip FreeBSD-src-f671832d7667351a66ab594f63d8cd4ef66e8e91.tar.gz |
- Make the mutex code almost completely machine independent. This greatly
reducues the maintenance load for the mutex code. The only MD portions
of the mutex code are in machine/mutex.h now, which include the assembly
macros for handling mutexes as well as optionally overriding the mutex
micro-operations. For example, we use optimized micro-ops on the x86
platform #ifndef I386_CPU.
- Change the behavior of the SMP_DEBUG kernel option. In the new code,
mtx_assert() only depends on INVARIANTS, allowing other kernel developers
to have working mutex assertiions without having to include all of the
mutex debugging code. The SMP_DEBUG kernel option has been renamed to
MUTEX_DEBUG and now just controls extra mutex debugging code.
- Abolish the ugly mtx_f hack. Instead, we dynamically allocate
seperate mtx_debug structures on the fly in mtx_init, except for mutexes
that are initiated very early in the boot process. These mutexes
are declared using a special MUTEX_DECLARE() macro, and use a new
flag MTX_COLD when calling mtx_init. This is still somewhat hackish,
but it is less evil than the mtx_f filler struct, and the mtx struct is
now the same size with and without mutex debugging code.
- Add some micro-micro-operation macros for doing the actual atomic
operations on the mutex mtx_lock field to make it easier for other archs
to override/optimize mutex ops if needed. These new tiny ops also clean
up the code in some places by replacing long atomic operation function
calls that spanned 2-3 lines with a short 1-line macro call.
- Don't call mi_switch() from mtx_enter_hard() when we block while trying
to obtain a sleep mutex. Calling mi_switch() would bogusly release
Giant before switching to the next process. Instead, inline most of the
code from mi_switch() in the mtx_enter_hard() function. Note that when
we finally kill Giant we can back this out and go back to calling
mi_switch().
Diffstat (limited to 'sys/alpha')
-rw-r--r-- | sys/alpha/alpha/synch_machdep.c | 550 | ||||
-rw-r--r-- | sys/alpha/include/mutex.h | 480 |
2 files changed, 12 insertions, 1018 deletions
diff --git a/sys/alpha/alpha/synch_machdep.c b/sys/alpha/alpha/synch_machdep.c deleted file mode 100644 index 184da83..0000000 --- a/sys/alpha/alpha/synch_machdep.c +++ /dev/null @@ -1,550 +0,0 @@ -/*- - * Copyright (c) 1997, 1998 Berkeley Software Design, Inc. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Berkeley Software Design Inc's name may not be used to endorse or - * promote products derived from this software without specific prior - * written permission. - * - * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - * - * from BSDI $Id: synch_machdep.c,v 2.3.2.39 2000/04/27 03:10:25 cp Exp $ - * $FreeBSD$ - */ - -#define MTX_STRS /* define common strings */ - -#include <sys/param.h> -#include <sys/proc.h> -#include <sys/systm.h> -#include <sys/kernel.h> -#include <sys/ktr.h> -#include <vm/vm.h> -#include <vm/vm_extern.h> -#include <ddb/ddb.h> -#include <machine/atomic.h> -#include <machine/clock.h> -#include <machine/cpu.h> -#include <machine/mutex.h> - -/* All mutexes in system (used for debug/panic) */ -struct mtx all_mtx = { MTX_UNOWNED, 0, 0, "All mutexes queue head", - TAILQ_HEAD_INITIALIZER(all_mtx.mtx_blocked), - { NULL, NULL }, &all_mtx, &all_mtx -#ifdef SMP_DEBUG - , NULL, { NULL, NULL }, NULL, 0 -#endif -}; - -int mtx_cur_cnt; -int mtx_max_cnt; - -extern void _mtx_enter_giant_def(void); -extern void _mtx_exit_giant_def(void); - -static void propagate_priority(struct proc *) __unused; - -#define mtx_unowned(m) ((m)->mtx_lock == MTX_UNOWNED) -#define mtx_owner(m) (mtx_unowned(m) ? NULL \ - : (struct proc *)((m)->mtx_lock & MTX_FLAGMASK)) - -#define RETIP(x) *(((u_int64_t *)(&x)) - 1) -#define SET_PRIO(p, pri) (p)->p_priority = (pri) - -/* - * XXX Temporary, for use from assembly language - */ - -void -_mtx_enter_giant_def(void) -{ - - mtx_enter(&Giant, MTX_DEF); -} - -void -_mtx_exit_giant_def(void) -{ - - mtx_exit(&Giant, MTX_DEF); -} - -static void -propagate_priority(struct proc *p) -{ - int pri = p->p_priority; - struct mtx *m = p->p_blocked; - - for (;;) { - struct proc *p1; - - p = mtx_owner(m); - - if (p == NULL) { - /* - * This really isn't quite right. Really - * ought to bump priority of process that - * next acquires the mutex. - */ - MPASS(m->mtx_lock == MTX_CONTESTED); - return; - } - MPASS(p->p_magic == P_MAGIC); - if (p->p_priority <= pri) - return; - /* - * If lock holder is actually running, just bump priority. - */ - if (TAILQ_NEXT(p, p_procq) == NULL) { - MPASS(p->p_stat == SRUN || p->p_stat == SZOMB); - SET_PRIO(p, pri); - return; - } - /* - * If on run queue move to new run queue, and - * quit. - */ - if (p->p_stat == SRUN) { - MPASS(p->p_blocked == NULL); - remrunqueue(p); - SET_PRIO(p, pri); - setrunqueue(p); - return; - } - - /* - * If we aren't blocked on a mutex, give up and quit. - */ - if (p->p_stat != SMTX) { - return; - } - - /* - * Pick up the mutex that p is blocked on. - */ - m = p->p_blocked; - MPASS(m != NULL); - - /* - * Check if the proc needs to be moved up on - * the blocked chain - */ - if ((p1 = TAILQ_PREV(p, rq, p_procq)) == NULL || - p1->p_priority <= pri) - continue; - - /* - * Remove proc from blocked chain - */ - TAILQ_REMOVE(&m->mtx_blocked, p, p_procq); - TAILQ_FOREACH(p1, &m->mtx_blocked, p_procq) { - MPASS(p1->p_magic == P_MAGIC); - if (p1->p_priority > pri) - break; - } - if (p1) - TAILQ_INSERT_BEFORE(p1, p, p_procq); - else - TAILQ_INSERT_TAIL(&m->mtx_blocked, p, p_procq); - CTR4(KTR_LOCK, - "propagate priority: p 0x%p moved before 0x%p on [0x%p] %s", - p, p1, m, m->mtx_description); - } -} - -void -mtx_enter_hard(struct mtx *m, int type, int ipl) -{ - struct proc *p = CURPROC; - - KASSERT(p != NULL, ("curproc is NULL in mutex")); - - switch (type) { - case MTX_DEF: - if ((m->mtx_lock & MTX_FLAGMASK) == (u_int64_t)p) { - m->mtx_recurse++; - atomic_set_64(&m->mtx_lock, MTX_RECURSE); - CTR1(KTR_LOCK, "mtx_enter: 0x%p recurse", m); - return; - } - CTR3(KTR_LOCK, "mtx_enter: 0x%p contested (lock=%lx) [0x%lx]", - m, m->mtx_lock, RETIP(m)); - while (!atomic_cmpset_64(&m->mtx_lock, MTX_UNOWNED, - (u_int64_t)p)) { - int v; - struct proc *p1; - - mtx_enter(&sched_lock, MTX_SPIN | MTX_RLIKELY); - /* - * check if the lock has been released while - * waiting for the schedlock. - */ - if ((v = m->mtx_lock) == MTX_UNOWNED) { - mtx_exit(&sched_lock, MTX_SPIN); - continue; - } - /* - * The mutex was marked contested on release. This - * means that there are processes blocked on it. - */ - if (v == MTX_CONTESTED) { - p1 = TAILQ_FIRST(&m->mtx_blocked); - KASSERT(p1 != NULL, ("contested mutex has no contesters")); - KASSERT(p != NULL, ("curproc is NULL for contested mutex")); - m->mtx_lock = (u_int64_t)p | MTX_CONTESTED; - if (p1->p_priority < p->p_priority) { - SET_PRIO(p, p1->p_priority); - } - mtx_exit(&sched_lock, MTX_SPIN); - return; - } - /* - * If the mutex isn't already contested and - * a failure occurs setting the contested bit the - * mutex was either release or the - * state of the RECURSION bit changed. - */ - if ((v & MTX_CONTESTED) == 0 && - !atomic_cmpset_64(&m->mtx_lock, v, - v | MTX_CONTESTED)) { - mtx_exit(&sched_lock, MTX_SPIN); - continue; - } - - /* We definitely have to sleep for this lock */ - mtx_assert(m, MA_NOTOWNED); - -#ifdef notyet - /* - * If we're borrowing an interrupted thread's VM - * context must clean up before going to sleep. - */ - if (p->p_flag & (P_ITHD | P_SITHD)) { - ithd_t *it = (ithd_t *)p; - - if (it->it_interrupted) { - CTR2(KTR_LOCK, - "mtx_enter: 0x%x interrupted 0x%x", - it, it->it_interrupted); - intr_thd_fixup(it); - } - } -#endif - - /* Put us on the list of procs blocked on this mutex */ - if (TAILQ_EMPTY(&m->mtx_blocked)) { - p1 = (struct proc *)(m->mtx_lock & - MTX_FLAGMASK); - LIST_INSERT_HEAD(&p1->p_contested, m, - mtx_contested); - TAILQ_INSERT_TAIL(&m->mtx_blocked, p, p_procq); - } else { - TAILQ_FOREACH(p1, &m->mtx_blocked, p_procq) - if (p1->p_priority > p->p_priority) - break; - if (p1) - TAILQ_INSERT_BEFORE(p1, p, p_procq); - else - TAILQ_INSERT_TAIL(&m->mtx_blocked, p, - p_procq); - } - - p->p_blocked = m; /* Who we're blocked on */ - p->p_stat = SMTX; -#if 0 - propagate_priority(p); -#endif - CTR3(KTR_LOCK, "mtx_enter: p 0x%p blocked on [0x%p] %s", - p, m, m->mtx_description); - mi_switch(); - CTR3(KTR_LOCK, - "mtx_enter: p 0x%p free from blocked on [0x%p] %s", - p, m, m->mtx_description); - mtx_exit(&sched_lock, MTX_SPIN); - } - alpha_mb(); - return; - case MTX_SPIN: - case MTX_SPIN | MTX_FIRST: - case MTX_SPIN | MTX_TOPHALF: - { - int i = 0; - - if (m->mtx_lock == (u_int64_t)p) { - m->mtx_recurse++; - return; - } - CTR1(KTR_LOCK, "mtx_enter: %p spinning", m); - for (;;) { - if (atomic_cmpset_64(&m->mtx_lock, MTX_UNOWNED, - (u_int64_t)p)) { - alpha_mb(); - break; - } - while (m->mtx_lock != MTX_UNOWNED) { - if (i++ < 1000000) - continue; - if (i++ < 6000000) - DELAY (1); -#ifdef DDB - else if (!db_active) -#else - else -#endif - panic( - "spin lock %s held by 0x%lx for > 5 seconds", - m->mtx_description, m->mtx_lock); - } - } - -#ifdef SMP_DEBUG - if (type != MTX_SPIN) - m->mtx_saveipl = 0xbeefface; - else -#endif - m->mtx_saveipl = ipl; - CTR1(KTR_LOCK, "mtx_enter: 0x%p spin done", m); - return; - } - } -} - -void -mtx_exit_hard(struct mtx *m, int type) -{ - struct proc *p, *p1; - struct mtx *m1; - int pri; - - switch (type) { - case MTX_DEF: - case MTX_DEF | MTX_NOSWITCH: - if (m->mtx_recurse != 0) { - if (--(m->mtx_recurse) == 0) - atomic_clear_64(&m->mtx_lock, MTX_RECURSE); - CTR1(KTR_LOCK, "mtx_exit: 0x%p unrecurse", m); - return; - } - mtx_enter(&sched_lock, MTX_SPIN); - CTR1(KTR_LOCK, "mtx_exit: 0x%p contested", m); - p = CURPROC; - p1 = TAILQ_FIRST(&m->mtx_blocked); - MPASS(p->p_magic == P_MAGIC); - MPASS(p1->p_magic == P_MAGIC); - TAILQ_REMOVE(&m->mtx_blocked, p1, p_procq); - if (TAILQ_EMPTY(&m->mtx_blocked)) { - LIST_REMOVE(m, mtx_contested); - atomic_cmpset_64(&m->mtx_lock, m->mtx_lock, - MTX_UNOWNED); - CTR1(KTR_LOCK, "mtx_exit: 0x%p not held", m); - } else - m->mtx_lock = MTX_CONTESTED; - pri = MAXPRI; - LIST_FOREACH(m1, &p->p_contested, mtx_contested) { - int cp = TAILQ_FIRST(&m1->mtx_blocked)->p_priority; - if (cp < pri) - pri = cp; - } - if (pri > p->p_nativepri) - pri = p->p_nativepri; - SET_PRIO(p, pri); - CTR2(KTR_LOCK, "mtx_exit: 0x%p contested setrunqueue 0x%p", - m, p1); - p1->p_blocked = NULL; - p1->p_stat = SRUN; - setrunqueue(p1); - if ((type & MTX_NOSWITCH) == 0 && p1->p_priority < pri) { -#ifdef notyet - if (p->p_flag & (P_ITHD | P_SITHD)) { - ithd_t *it = (ithd_t *)p; - - if (it->it_interrupted) { - CTR2(KTR_LOCK, - "mtx_exit: 0x%x interruped 0x%x", - it, it->it_interrupted); - intr_thd_fixup(it); - } - } -#endif - setrunqueue(p); - CTR2(KTR_LOCK, "mtx_exit: 0x%p switching out lock=0x%lx", - m, m->mtx_lock); - mi_switch(); - CTR2(KTR_LOCK, "mtx_exit: 0x%p resuming lock=0x%lx", - m, m->mtx_lock); - } - mtx_exit(&sched_lock, MTX_SPIN); - return; - case MTX_SPIN: - case MTX_SPIN | MTX_FIRST: - if (m->mtx_recurse != 0) { - m->mtx_recurse--; - return; - } - alpha_mb(); - if (atomic_cmpset_64(&m->mtx_lock, CURTHD, MTX_UNOWNED)) { - if (type & MTX_FIRST) - enable_intr(); /* XXX is this kosher? */ - else { - MPASS(m->mtx_saveipl != 0xbeefface); - alpha_pal_swpipl(m->mtx_saveipl); - } - return; - } - panic("unsucuessful release of spin lock"); - case MTX_SPIN | MTX_TOPHALF: - if (m->mtx_recurse != 0) { - m->mtx_recurse--; - return; - } - alpha_mb(); - if (atomic_cmpset_64(&m->mtx_lock, CURTHD, MTX_UNOWNED)) - return; - panic("unsucuessful release of spin lock"); - default: - panic("mtx_exit_hard: unsupported type 0x%x\n", type); - } -} - -#define MV_DESTROY 0 /* validate before destory */ -#define MV_INIT 1 /* validate before init */ - -#ifdef SMP_DEBUG - -#define ISK0SEG(va) \ - ((va >= ALPHA_K0SEG_BASE && va <= ALPHA_K0SEG_END)) - -int mtx_validate __P((struct mtx *, int)); - -int -mtx_validate(struct mtx *m, int when) -{ - struct mtx *mp; - int i; - int retval = 0; - - if (m == &all_mtx || cold) - return 0; - - mtx_enter(&all_mtx, MTX_DEF); - ASS(ISK0SEG((vm_offset_t)all_mtx.mtx_next) || - kernacc((caddr_t)all_mtx.mtx_next, 4, 1) == 1); - ASS(all_mtx.mtx_next->mtx_prev == &all_mtx); - for (i = 0, mp = all_mtx.mtx_next; mp != &all_mtx; mp = mp->mtx_next) { - if (!ISK0SEG((vm_offset_t)all_mtx.mtx_next) && - kernacc((caddr_t)mp->mtx_next, 4, 1) != 1) { - panic("mtx_validate: mp=%p mp->mtx_next=%p", - mp, mp->mtx_next); - } - i++; - if (i > mtx_cur_cnt) { - panic("mtx_validate: too many in chain, known=%d\n", - mtx_cur_cnt); - } - } - ASS(i == mtx_cur_cnt); - switch (when) { - case MV_DESTROY: - for (mp = all_mtx.mtx_next; mp != &all_mtx; mp = mp->mtx_next) - if (mp == m) - break; - ASS(mp == m); - break; - case MV_INIT: - for (mp = all_mtx.mtx_next; mp != &all_mtx; mp = mp->mtx_next) - if (mp == m) { - /* - * Not good. This mutex already exists. - */ - retval = 1; -#if 1 - printf("re-initing existing mutex %s\n", - m->mtx_description); - ASS(m->mtx_lock == MTX_UNOWNED); - retval = 1; -#else - panic("re-initing existing mutex %s", - m->mtx_description); -#endif - } - } - mtx_exit(&all_mtx, MTX_DEF); - return (retval); -} -#endif - -void -mtx_init(struct mtx *m, char *t, int flag) -{ - - CTR2(KTR_LOCK, "mtx_init 0x%p (%s)", m, t); -#ifdef SMP_DEBUG - if (mtx_validate(m, MV_INIT)) /* diagnostic and error correction */ - return; -#endif - bzero((void *)m, sizeof *m); - TAILQ_INIT(&m->mtx_blocked); - m->mtx_description = t; - m->mtx_lock = MTX_UNOWNED; - /* Put on all mutex queue */ - mtx_enter(&all_mtx, MTX_DEF); - m->mtx_next = &all_mtx; - m->mtx_prev = all_mtx.mtx_prev; - m->mtx_prev->mtx_next = m; - all_mtx.mtx_prev = m; - if (++mtx_cur_cnt > mtx_max_cnt) - mtx_max_cnt = mtx_cur_cnt; - mtx_exit(&all_mtx, MTX_DEF); - witness_init(m, flag); -} - -void -mtx_destroy(struct mtx *m) -{ - - CTR2(KTR_LOCK, "mtx_destroy 0x%p (%s)", m, m->mtx_description); -#ifdef SMP_DEBUG - if (m->mtx_next == NULL) - panic("mtx_destroy: %p (%s) already destroyed", - m, m->mtx_description); - - if (!mtx_owned(m)) { - ASS(m->mtx_lock == MTX_UNOWNED); - } else { - ASS((m->mtx_lock & (MTX_RECURSE|MTX_CONTESTED)) == 0); - } - mtx_validate(m, MV_DESTROY); /* diagnostic */ -#endif - -#ifdef WITNESS - if (m->mtx_witness) - witness_destroy(m); -#endif /* WITNESS */ - - /* Remove from the all mutex queue */ - mtx_enter(&all_mtx, MTX_DEF); - m->mtx_next->mtx_prev = m->mtx_prev; - m->mtx_prev->mtx_next = m->mtx_next; -#ifdef SMP_DEBUG - m->mtx_next = m->mtx_prev = NULL; -#endif - mtx_cur_cnt--; - mtx_exit(&all_mtx, MTX_DEF); -} diff --git a/sys/alpha/include/mutex.h b/sys/alpha/include/mutex.h index 12b12a8..5ccc28d 100644 --- a/sys/alpha/include/mutex.h +++ b/sys/alpha/include/mutex.h @@ -33,293 +33,39 @@ #define _MACHINE_MUTEX_H_ #ifndef LOCORE -#include <sys/queue.h> #ifdef _KERNEL -#include <sys/ktr.h> -#include <sys/proc.h> /* Needed for curproc. */ -#include <machine/atomic.h> -#include <machine/cpufunc.h> -#include <machine/globaldata.h> -#include <machine/globals.h> - -/* - * If kern_mutex.c is being built, compile non-inlined versions of various - * functions so that kernel modules can use them. - */ -#ifndef _KERN_MUTEX_C_ -#define _MTX_INLINE static __inline -#else -#define _MTX_INLINE -#endif - -/* - * Mutex flags - * - * Types - */ -#define MTX_DEF 0x1 /* Default (spin/sleep) */ -#define MTX_SPIN 0x2 /* Spin only lock */ - -/* Options */ -#define MTX_RLIKELY 0x4 /* (opt) Recursion likely */ -#define MTX_NORECURSE 0x8 /* No recursion possible */ -#define MTX_NOSPIN 0x10 /* Don't spin before sleeping */ -#define MTX_NOSWITCH 0x20 /* Do not switch on release */ -#define MTX_FIRST 0x40 /* First spin lock holder */ -#define MTX_TOPHALF 0x80 /* Interrupts not disabled on spin */ - -/* options that should be passed on to mtx_enter_hard, mtx_exit_hard */ -#define MTX_HARDOPTS (MTX_DEF | MTX_SPIN | MTX_FIRST | MTX_TOPHALF | MTX_NOSWITCH) - -/* Flags/value used in mtx_lock */ -#define MTX_RECURSE 0x01 /* (non-spin) lock held recursively */ -#define MTX_CONTESTED 0x02 /* (non-spin) lock contested */ -#define MTX_FLAGMASK ~(MTX_RECURSE | MTX_CONTESTED) -#define MTX_UNOWNED 0x8 /* Cookie for free mutex */ - -#endif /* _KERNEL */ - -/* - * Sleep/spin mutex - */ -struct mtx { - volatile u_int64_t mtx_lock; /* lock owner/gate/flags */ - volatile u_int32_t mtx_recurse; /* number of recursive holds */ - u_int32_t mtx_saveipl; /* saved ipl (for spin locks) */ - char *mtx_description; - TAILQ_HEAD(, proc) mtx_blocked; - LIST_ENTRY(mtx) mtx_contested; - struct mtx *mtx_next; /* all locks in system */ - struct mtx *mtx_prev; -#ifdef SMP_DEBUG - /* If you add anything here, adjust the mtxf_t definition below */ - struct witness *mtx_witness; - LIST_ENTRY(mtx) mtx_held; - const char *mtx_file; - int mtx_line; -#endif /* SMP_DEBUG */ -}; - -/* - * Filler for structs which need to remain the same size - * whether or not SMP_DEBUG is turned on. - */ -typedef struct mtxf { -#ifdef SMP_DEBUG - char mtxf_data[0]; -#else - char mtxf_data[4*sizeof(void *) + sizeof(int)]; -#endif -} mtxf_t; - -#define mp_fixme(string) - -#ifdef _KERNEL -/* Misc */ -#define CURTHD ((u_int64_t)CURPROC) /* Current thread ID */ - -/* Prototypes */ -void mtx_init(struct mtx *m, char *description, int flag); -void mtx_enter_hard(struct mtx *, int type, int ipl); -void mtx_exit_hard(struct mtx *, int type); -void mtx_destroy(struct mtx *m); - -/* - * Wrap the following functions with cpp macros so that filenames and line - * numbers are embedded in the code correctly. - */ -#if (defined(KLD_MODULE) || defined(_KERN_MUTEX_C_)) -void _mtx_enter(struct mtx *mtxp, int type, const char *file, int line); -int _mtx_try_enter(struct mtx *mtxp, int type, const char *file, int line); -void _mtx_exit(struct mtx *mtxp, int type, const char *file, int line); -#endif - -#define mtx_enter(mtxp, type) \ - _mtx_enter((mtxp), (type), __FILE__, __LINE__) - -#define mtx_try_enter(mtxp, type) \ - _mtx_try_enter((mtxp), (type), __FILE__, __LINE__) - -#define mtx_exit(mtxp, type) \ - _mtx_exit((mtxp), (type), __FILE__, __LINE__) - -/* Global locks */ -extern struct mtx sched_lock; -extern struct mtx Giant; - -/* - * Used to replace return with an exit Giant and return. - */ - -#define EGAR(a) \ -do { \ - mtx_exit(&Giant, MTX_DEF); \ - return (a); \ -} while (0) - -#define VEGAR \ -do { \ - mtx_exit(&Giant, MTX_DEF); \ - return; \ -} while (0) - -#define DROP_GIANT() \ -do { \ - int _giantcnt; \ - WITNESS_SAVE_DECL(Giant); \ - \ - WITNESS_SAVE(&Giant, Giant); \ - for (_giantcnt = 0; mtx_owned(&Giant); _giantcnt++) \ - mtx_exit(&Giant, MTX_DEF) - -#define PICKUP_GIANT() \ - mtx_assert(&Giant, MA_NOTOWNED); \ - while (_giantcnt--) \ - mtx_enter(&Giant, MTX_DEF); \ - WITNESS_RESTORE(&Giant, Giant); \ -} while (0) - -#define PARTIAL_PICKUP_GIANT() \ - mtx_assert(&Giant, MA_NOTOWNED); \ - while (_giantcnt--) \ - mtx_enter(&Giant, MTX_DEF); \ - WITNESS_RESTORE(&Giant, Giant) - /* * Debugging */ -#ifndef SMP_DEBUG -#define mtx_assert(m, what) -#else /* SMP_DEBUG */ +#ifdef MUTEX_DEBUG -#define MA_OWNED 1 -#define MA_NOTOWNED 2 -#define mtx_assert(m, what) { \ - switch ((what)) { \ - case MA_OWNED: \ - ASS(mtx_owned((m))); \ - break; \ - case MA_NOTOWNED: \ - ASS(!mtx_owned((m))); \ - break; \ - default: \ - panic("unknown mtx_assert at %s:%d", __FILE__, __LINE__); \ - } \ -} - -#ifdef INVARIANTS -#define ASS(ex) MPASS(ex) -#define MPASS(ex) if (!(ex)) panic("Assertion %s failed at %s:%d", \ - #ex, __FILE__, __LINE__) -#define MPASS2(ex, what) if (!(ex)) panic("Assertion %s failed at %s:%d", \ - what, __FILE__, __LINE__) - -#ifdef MTX_STRS -char STR_IEN[] = "fl & 0x200"; -char STR_IDIS[] = "!(fl & 0x200)"; -#else /* MTX_STRS */ +#ifdef _KERN_MUTEX_C_ +char STR_IEN[] = "ps & IPL != IPL_HIGH"; +char STR_IDIS[] = "ps & IPL == IPL_HIGH"; +char STR_SIEN[] = "mpp->mtx_saveintr != IPL_HIGH"; +#else /* _KERN_MUTEX_C_ */ extern char STR_IEN[]; extern char STR_IDIS[]; -#endif /* MTX_STRS */ +extern char STR_SIEN[]; +#endif /* _KERN_MUTEX_C_ */ + +#endif /* MUTEX_DEBUG */ + #define ASS_IEN MPASS2((alpha_pal_rdps() & ALPHA_PSL_IPL_MASK) \ == ALPHA_PSL_IPL_HIGH, STR_IEN) #define ASS_IDIS MPASS2((alpha_pal_rdps() & ALPHA_PSL_IPL_MASK) \ != ALPHA_PSL_IPL_HIGH, STR_IDIS) -#endif /* INVARIANTS */ - -#endif /* SMP_DEBUG */ - -#if !defined(SMP_DEBUG) || !defined(INVARIANTS) -#define ASS(ex) -#define MPASS(ex) -#define MPASS2(ex, where) -#define ASS_IEN -#define ASS_IDIS -#endif /* !defined(SMP_DEBUG) || !defined(INVARIANTS) */ - -#ifdef WITNESS -#ifndef SMP_DEBUG -#error WITNESS requires SMP_DEBUG -#endif /* SMP_DEBUG */ -#define WITNESS_ENTER(m, t, f, l) \ - if ((m)->mtx_witness != NULL) \ - witness_enter((m), (t), (f), (l)) -#define WITNESS_EXIT(m, t, f, l) \ - if ((m)->mtx_witness != NULL) \ - witness_exit((m), (t), (f), (l)) - -#define WITNESS_SLEEP(check, m) witness_sleep(check, (m), __FILE__, __LINE__) -#define WITNESS_SAVE_DECL(n) \ - const char * __CONCAT(n, __wf); \ - int __CONCAT(n, __wl) - -#define WITNESS_SAVE(m, n) \ -do { \ - if ((m)->mtx_witness != NULL) \ - witness_save(m, &__CONCAT(n, __wf), &__CONCAT(n, __wl)); \ -} while (0) - -#define WITNESS_RESTORE(m, n) \ -do { \ - if ((m)->mtx_witness != NULL) \ - witness_restore(m, __CONCAT(n, __wf), __CONCAT(n, __wl)); \ -} while (0) - -void witness_init(struct mtx *, int flag); -void witness_destroy(struct mtx *); -void witness_enter(struct mtx *, int, const char *, int); -void witness_try_enter(struct mtx *, int, const char *, int); -void witness_exit(struct mtx *, int, const char *, int); -void witness_display(void(*)(const char *fmt, ...)); -void witness_list(struct proc *); -int witness_sleep(int, struct mtx *, const char *, int); -void witness_save(struct mtx *, const char **, int *); -void witness_restore(struct mtx *, const char *, int); -#else /* WITNESS */ -#define WITNESS_ENTER(m, t, f, l) -#define WITNESS_EXIT(m, t, f, l) -#define WITNESS_SLEEP(check, m) -#define WITNESS_SAVE_DECL(n) -#define WITNESS_SAVE(m, n) -#define WITNESS_RESTORE(m, n) - -/* - * flag++ is slezoid way of shutting up unused parameter warning - * in mtx_init() - */ -#define witness_init(m, flag) flag++ -#define witness_destroy(m) -#define witness_enter(m, t, f, l) -#define witness_try_enter(m, t, f, l) -#define witness_exit(m, t, f, l) -#endif /* WITNESS */ +#define ASS_SIEN(mpp) MPASS2((mpp)->saveintr != ALPHA_PSL_IPL_HIGH, STR_SIEN) /* * Assembly macros (for internal use only) *-------------------------------------------------------------------------- */ -/* - * Get a sleep lock, deal with recursion inline - */ - #define _V(x) __STRING(x) -#define _getlock_sleep(mp, tid, type) do { \ - if (atomic_cmpset_64(&(mp)->mtx_lock, MTX_UNOWNED, (tid)) == 0) { \ - if (((mp)->mtx_lock & MTX_FLAGMASK) != (tid)) \ - mtx_enter_hard(mp, (type) & MTX_HARDOPTS, 0); \ - else { \ - atomic_set_64(&(mp)->mtx_lock, MTX_RECURSE); \ - (mp)->mtx_recurse++; \ - } \ - } else { \ - alpha_mb(); \ - } \ -} while (0) - /* * Get a spin lock, handle recusion inline (as the less common case) */ @@ -334,208 +80,6 @@ void witness_restore(struct mtx *, const char *, int); } \ } while (0) -/* - * Get a lock without any recursion handling. Calls the hard enter - * function if we can't get it inline. - */ - -#define _getlock_norecurse(mp, tid, type) do { \ - if (atomic_cmpset_64(&(mp)->mtx_lock, MTX_UNOWNED, (tid)) == 0) \ - mtx_enter_hard((mp), (type) & MTX_HARDOPTS, 0); \ - else \ - alpha_mb(); \ -} while (0) - -/* - * Release a sleep lock assuming we haven't recursed on it, recursion is - * handled in the hard function. - */ - -#define _exitlock_norecurse(mp, tid, type) do { \ - alpha_mb(); \ - if (atomic_cmpset_64(&(mp)->mtx_lock, (tid), MTX_UNOWNED) == 0) \ - mtx_exit_hard((mp), (type) & MTX_HARDOPTS); \ -} while (0) - -/* - * Release a sleep lock when its likely we recursed (the code to - * deal with simple recursion is inline). - */ - -#define _exitlock(mp, tid, type) do { \ - alpha_mb(); \ - if (atomic_cmpset_64(&(mp)->mtx_lock, (tid), MTX_UNOWNED) == 0) {\ - if (((mp)->mtx_lock & MTX_RECURSE) && \ - (--(mp)->mtx_recurse == 0)) \ - atomic_clear_64(&(mp)->mtx_lock, MTX_RECURSE); \ - else \ - mtx_exit_hard((mp), (type) & MTX_HARDOPTS); \ - } \ -} while (0) - -/* - * Release a spin lock (with possible recursion) - */ - -#define _exitlock_spin(mp) do { \ - alpha_mb(); \ - if ((mp)->mtx_recurse == 0) { \ - int _ipl = (mp)->mtx_saveipl; \ - atomic_cmpset_64(&(mp)->mtx_lock, (mp)->mtx_lock, \ - MTX_UNOWNED); \ - alpha_pal_swpipl(_ipl); \ - } else { \ - (mp)->mtx_recurse--; \ - } \ -} while (0) - -/* - * Externally visible mutex functions - *------------------------------------------------------------------------ - */ - -/* - * Return non-zero if a mutex is already owned by the current thread - */ -#define mtx_owned(m) (((m)->mtx_lock & MTX_FLAGMASK) == CURTHD) - -/* Common strings */ -#ifdef MTX_STRS -char STR_mtx_enter_fmt[] = "GOT %s [%p] at %s:%d r=%d"; -char STR_mtx_bad_type[] = "((type) & (MTX_NORECURSE | MTX_NOSWITCH)) == 0"; -char STR_mtx_exit_fmt[] = "REL %s [%p] at %s:%d r=%d"; -char STR_mtx_owned[] = "mtx_owned(mpp)"; -char STR_mtx_recurse[] = "mpp->mtx_recurse == 0"; -char STR_mtx_try_enter_fmt[] = "TRY_ENTER %s [%p] at %s:%d result=%d"; -#else /* MTX_STRS */ -extern char STR_mtx_enter_fmt[]; -extern char STR_mtx_bad_type[]; -extern char STR_mtx_exit_fmt[]; -extern char STR_mtx_owned[]; -extern char STR_mtx_recurse[]; -extern char STR_mtx_try_enter_fmt[]; -#endif /* MTX_STRS */ - -#ifndef KLD_MODULE -/* - * Get lock 'm', the macro handles the easy (and most common cases) and - * leaves the slow stuff to the mtx_enter_hard() function. - * - * Note: since type is usually a constant much of this code is optimized out - */ -_MTX_INLINE void -_mtx_enter(struct mtx *mtxp, int type, const char *file, int line) -{ - struct mtx *mpp = mtxp; - - /* bits only valid on mtx_exit() */ - MPASS2(((type) & (MTX_NORECURSE | MTX_NOSWITCH)) == 0, - STR_mtx_bad_type); - - if ((type) & MTX_SPIN) { - /* - * Easy cases of spin locks: - * - * 1) We already own the lock and will simply recurse on it (if - * RLIKELY) - * - * 2) The lock is free, we just get it - */ - if ((type) & MTX_RLIKELY) { - /* - * Check for recursion, if we already have this lock we - * just bump the recursion count. - */ - if (mpp->mtx_lock == CURTHD) { - mpp->mtx_recurse++; - goto done; - } - } - - if (((type) & MTX_TOPHALF) == 0) { - /* - * If an interrupt thread uses this we must block - * interrupts here. - */ - _getlock_spin_block(mpp, CURTHD, (type) & MTX_HARDOPTS); - } else - _getlock_norecurse(mpp, CURTHD, (type) & MTX_HARDOPTS); - } else { - /* Sleep locks */ - if ((type) & MTX_RLIKELY) - _getlock_sleep(mpp, CURTHD, (type) & MTX_HARDOPTS); - else - _getlock_norecurse(mpp, CURTHD, (type) & MTX_HARDOPTS); - } - done: - WITNESS_ENTER(mpp, type, file, line); - CTR5(KTR_LOCK, STR_mtx_enter_fmt, - mpp->mtx_description, mpp, file, line, - mpp->mtx_recurse); -} - -/* - * Attempt to get MTX_DEF lock, return non-zero if lock acquired - * - * XXX DOES NOT HANDLE RECURSION - */ -_MTX_INLINE int -_mtx_try_enter(struct mtx *mtxp, int type, const char *file, int line) -{ - struct mtx *const mpp = mtxp; - int rval; - - rval = atomic_cmpset_64(&mpp->mtx_lock, MTX_UNOWNED, CURTHD); -#ifdef SMP_DEBUG - if (rval && mpp->mtx_witness != NULL) { - ASS(mpp->mtx_recurse == 0); - witness_try_enter(mpp, type, file, line); - } -#endif - CTR5(KTR_LOCK, STR_mtx_try_enter_fmt, - mpp->mtx_description, mpp, file, line, rval); - - return rval; -} - -/* - * Release lock m - */ -_MTX_INLINE void -_mtx_exit(struct mtx *mtxp, int type, const char *file, int line) -{ - struct mtx *const mpp = mtxp; - - MPASS2(mtx_owned(mpp), STR_mtx_owned); - WITNESS_EXIT(mpp, type, file, line); - CTR5(KTR_LOCK, STR_mtx_exit_fmt, - mpp->mtx_description, mpp, file, line, - mpp->mtx_recurse); - if ((type) & MTX_SPIN) { - if ((type) & MTX_NORECURSE) { - MPASS2(mpp->mtx_recurse == 0, STR_mtx_recurse); - atomic_cmpset_64(&mpp->mtx_lock, mpp->mtx_lock, - MTX_UNOWNED); - if (((type) & MTX_TOPHALF) == 0) - alpha_pal_swpipl(mpp->mtx_saveipl); - } else - if ((type) & MTX_TOPHALF) { - _exitlock_norecurse(mpp, CURTHD, - (type) & MTX_HARDOPTS); - } else - _exitlock_spin(mpp); - } else { - /* Handle sleep locks */ - if ((type) & MTX_RLIKELY) - _exitlock(mpp, CURTHD, (type) & MTX_HARDOPTS); - else { - _exitlock_norecurse(mpp, CURTHD, - (type) & MTX_HARDOPTS); - } - } -} - -#endif /* KLD_MODULE */ #endif /* _KERNEL */ #else /* !LOCORE */ |