[apple/xnu.git] / bsd / dev / dtrace / lockstat.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/* #pragma ident	"@(#)lockstat.c	1.12	08/01/16 SMI" */


#ifdef KERNEL
#ifndef _KERNEL
#define _KERNEL /* Solaris vs. Darwin */
#endif
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <miscfs/devfs/devfs.h>

#include <sys/dtrace.h>
#include <sys/dtrace_impl.h>

#include <sys/dtrace_glue.h>

#include <sys/lockstat.h>

#include <kern/processor.h>

#define membar_producer dtrace_membar_producer

/*
 * Hot patch values, x86
 */
#if defined(__i386__) || defined(__x86_64__)
#define	NOP	0x90
#define	RET	0xc3
#define LOCKSTAT_AFRAMES 1
#else
#error "not ported to this architecture"
#endif


typedef struct lockstat_probe {
	const char	*lsp_func;
	const char	*lsp_name;
	int		lsp_probe;
	dtrace_id_t	lsp_id;
} lockstat_probe_t;

lockstat_probe_t lockstat_probes[] =
{
#if defined(__i386__) || defined(__x86_64__)
	/* Not implemented yet on PPC... */
	{ LS_LCK_MTX_LOCK,	LSA_ACQUIRE,	LS_LCK_MTX_LOCK_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_MTX_LOCK,	LSA_SPIN,	LS_LCK_MTX_LOCK_SPIN, DTRACE_IDNONE },
	{ LS_LCK_MTX_TRY_LOCK,	LSA_ACQUIRE,	LS_LCK_MTX_TRY_LOCK_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_MTX_TRY_SPIN_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_SPIN_LOCK_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_MTX_UNLOCK,	LSA_RELEASE,	LS_LCK_MTX_UNLOCK_RELEASE, DTRACE_IDNONE },
	{ LS_LCK_MTX_EXT_LOCK,	LSA_ACQUIRE,	LS_LCK_MTX_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_MTX_EXT_LOCK,	LSA_SPIN,	LS_LCK_MTX_EXT_LOCK_SPIN, DTRACE_IDNONE },
	{ LS_LCK_MTX_EXT_TRY_LOCK, LSA_ACQUIRE,	LS_LCK_MTX_TRY_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_MTX_UNLOCK,	LSA_RELEASE,	LS_LCK_MTX_EXT_UNLOCK_RELEASE, DTRACE_IDNONE },
	{ LS_LCK_MTX_LOCK_SPIN_LOCK,	LSA_ACQUIRE,	LS_LCK_MTX_LOCK_SPIN_ACQUIRE, DTRACE_IDNONE },
#endif
	{ LS_LCK_MTX_LOCK,	LSA_BLOCK,	LS_LCK_MTX_LOCK_BLOCK, DTRACE_IDNONE },
	{ LS_LCK_MTX_EXT_LOCK,	LSA_BLOCK,	LS_LCK_MTX_EXT_LOCK_BLOCK, DTRACE_IDNONE },

	{ LS_LCK_RW_LOCK_SHARED,	LSR_ACQUIRE,	LS_LCK_RW_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_SHARED,	LSR_BLOCK,	LS_LCK_RW_LOCK_SHARED_BLOCK, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_SHARED,	LSR_SPIN,	LS_LCK_RW_LOCK_SHARED_SPIN, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_EXCL,		LSR_ACQUIRE,	LS_LCK_RW_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_EXCL,		LSR_BLOCK,	LS_LCK_RW_LOCK_EXCL_BLOCK, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_EXCL,		LSR_SPIN,	LS_LCK_RW_LOCK_EXCL_SPIN, DTRACE_IDNONE },
	{ LS_LCK_RW_DONE,		LSR_RELEASE,	LS_LCK_RW_DONE_RELEASE, DTRACE_IDNONE },
	{ LS_LCK_RW_TRY_LOCK_SHARED,	LSR_ACQUIRE,	LS_LCK_RW_TRY_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_RW_TRY_LOCK_EXCL,	LSR_ACQUIRE,	LS_LCK_RW_TRY_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_UPGRADE,	LS_LCK_RW_LOCK_SHARED_TO_EXCL_UPGRADE, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL,	LSR_BLOCK,	LS_LCK_RW_LOCK_SHARED_TO_EXCL_BLOCK, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL,	LSR_SPIN,	LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN, DTRACE_IDNONE },
	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED,	LSR_DOWNGRADE,	LS_LCK_RW_LOCK_EXCL_TO_SHARED_DOWNGRADE, DTRACE_IDNONE },


#ifdef	LATER
	/* Interlock and spinlock measurements would be nice, but later */
	{ LS_LCK_SPIN_LOCK,	LSS_ACQUIRE,	LS_LCK_SPIN_LOCK_ACQUIRE, DTRACE_IDNONE },
	{ LS_LCK_SPIN_LOCK,	LSS_SPIN,	LS_LCK_SPIN_LOCK_SPIN, DTRACE_IDNONE },
	{ LS_LCK_SPIN_UNLOCK,	LSS_RELEASE,	LS_LCK_SPIN_UNLOCK_RELEASE, DTRACE_IDNONE },

	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED,	LSA_ILK_SPIN,	LS_LCK_RW_LOCK_EXCL_TO_SHARED_ILK_SPIN, DTRACE_IDNONE },
	{ LS_LCK_MTX_LOCK,	LSA_ILK_SPIN,	LS_LCK_MTX_LOCK_ILK_SPIN, DTRACE_IDNONE },
	{ LS_LCK_MTX_EXT_LOCK,	LSA_ILK_SPIN,	LS_LCK_MTX_EXT_LOCK_ILK_SPIN, DTRACE_IDNONE },
	{ LS_LCK_RW_TRY_LOCK_EXCL,	LSA_ILK_SPIN,	LS_LCK_RW_TRY_LOCK_EXCL_ILK_SPIN, DTRACE_IDNONE },
	{ LS_LCK_RW_TRY_LOCK_SHARED,	LSA_SPIN,	LS_LCK_RW_TRY_LOCK_SHARED_SPIN, DTRACE_IDNONE },
#endif

	{ NULL, NULL, 0, 0 }
};

dtrace_id_t lockstat_probemap[LS_NPROBES];

#if CONFIG_DTRACE
extern void lck_mtx_lock_lockstat_patch_point(void);
extern void lck_mtx_try_lock_lockstat_patch_point(void);
extern void lck_mtx_try_lock_spin_lockstat_patch_point(void);
extern void lck_mtx_unlock_lockstat_patch_point(void);
extern void lck_mtx_lock_ext_lockstat_patch_point(void);
extern void lck_mtx_ext_unlock_lockstat_patch_point(void);

extern void lck_rw_lock_shared_lockstat_patch_point(void);
extern void lck_rw_lock_exclusive_lockstat_patch_point(void);
extern void lck_rw_lock_shared_to_exclusive_lockstat_patch_point(void);
extern void lck_rw_try_lock_shared_lockstat_patch_point(void);
extern void lck_rw_try_lock_exclusive_lockstat_patch_point(void);
extern void lck_mtx_lock_spin_lockstat_patch_point(void);
#endif /* CONFIG_DTRACE */

vm_offset_t *assembly_probes[] = {
#if CONFIG_DTRACE
#if defined(__i386__) || defined(__x86_64__)
	/*
	 * On x86 these points are better done via hot patches, which ensure
	 * there is zero overhead when not in use.  On x86 these patch points
	 * are swapped between the return instruction and a no-op, with the
	 * Dtrace call following the return.
	 */ 
	(vm_offset_t *) lck_mtx_lock_lockstat_patch_point,
	(vm_offset_t *) lck_mtx_try_lock_lockstat_patch_point,
	(vm_offset_t *) lck_mtx_try_lock_spin_lockstat_patch_point,
	(vm_offset_t *) lck_mtx_unlock_lockstat_patch_point,
	(vm_offset_t *) lck_mtx_lock_ext_lockstat_patch_point,
	(vm_offset_t *) lck_mtx_ext_unlock_lockstat_patch_point,
	(vm_offset_t *) lck_rw_lock_shared_lockstat_patch_point,
	(vm_offset_t *) lck_rw_lock_exclusive_lockstat_patch_point,
	(vm_offset_t *) lck_rw_lock_shared_to_exclusive_lockstat_patch_point,
	(vm_offset_t *) lck_rw_try_lock_shared_lockstat_patch_point,
	(vm_offset_t *) lck_rw_try_lock_exclusive_lockstat_patch_point,
	(vm_offset_t *) lck_mtx_lock_spin_lockstat_patch_point,
#else
	(vm_offset_t *) lck_mtx_unlock_lockstat_patch_point,
#endif
#endif /* CONFIG_DTRACE */
	NULL
};
/*
 * Hot patch switches back and forth the probe points between NOP and RET.
 * The argument indicates whether the probe point is on or off.
 */
#if defined(__APPLE__)
static
#endif /* __APPLE__ */
void lockstat_hot_patch(boolean_t active)
{
#pragma unused(active)
	int i;


	for (i = 0; assembly_probes[i]; i++) {
#if defined(__i386__) || defined(__x86_64__)
		uint8_t instr;
		instr = (active ? NOP : RET );
		(void) ml_nofault_copy( (vm_offset_t)&instr, *(assembly_probes[i]), 
								sizeof(instr));
#endif
	}
}


void (*lockstat_probe)(dtrace_id_t, uint64_t, uint64_t,
				    uint64_t, uint64_t, uint64_t);

static dev_info_t	*lockstat_devi;	/* saved in xxattach() for xxinfo() */
static dtrace_provider_id_t lockstat_id;

/*ARGSUSED*/
static int
lockstat_enable(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg) /* __APPLE__ */
    
	lockstat_probe_t *probe = parg;

	ASSERT(!lockstat_probemap[probe->lsp_probe]);

	lockstat_probemap[probe->lsp_probe] = id;
	membar_producer();

	lockstat_hot_patch(TRUE);
	membar_producer();
	return(0);

}

/*ARGSUSED*/
static void
lockstat_disable(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg, id) /* __APPLE__ */

	lockstat_probe_t *probe = parg;
	int i;

	ASSERT(lockstat_probemap[probe->lsp_probe]);

	lockstat_probemap[probe->lsp_probe] = 0;
	lockstat_hot_patch(FALSE);
	membar_producer();

	/*
	 * See if we have any probes left enabled.
	 */
	for (i = 0; i < LS_NPROBES; i++) {
		if (lockstat_probemap[i]) {
			/*
			 * This probe is still enabled.  We don't need to deal
			 * with waiting for all threads to be out of the
			 * lockstat critical sections; just return.
			 */
			return;
		}
	}

}

/*ARGSUSED*/
static void
lockstat_provide(void *arg, const dtrace_probedesc_t *desc)
{
#pragma unused(arg, desc) /* __APPLE__ */
    
	int i = 0;

	for (i = 0; lockstat_probes[i].lsp_func != NULL; i++) {
		lockstat_probe_t *probe = &lockstat_probes[i];

		if (dtrace_probe_lookup(lockstat_id, "mach_kernel",
		    probe->lsp_func, probe->lsp_name) != 0)
			continue;

		ASSERT(!probe->lsp_id);
		probe->lsp_id = dtrace_probe_create(lockstat_id,
		    "mach_kernel", probe->lsp_func, probe->lsp_name,
		    LOCKSTAT_AFRAMES, probe);
	}
}


/*ARGSUSED*/
static void
lockstat_destroy(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg, id) /* __APPLE__ */
    
	lockstat_probe_t *probe = parg;

	ASSERT(!lockstat_probemap[probe->lsp_probe]);
	probe->lsp_id = 0;
}

static dtrace_pattr_t lockstat_attr = {
{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
};

static dtrace_pops_t lockstat_pops = {
	lockstat_provide,
	NULL,
	lockstat_enable,
	lockstat_disable,
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
	lockstat_destroy
};

static int
lockstat_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
{
	switch (cmd) {
	case DDI_ATTACH:
		break;
	case DDI_RESUME:
		return (DDI_SUCCESS);
	default:
		return (DDI_FAILURE);
	}

	if (ddi_create_minor_node(devi, "lockstat", S_IFCHR, 0,
	    DDI_PSEUDO, 0) == DDI_FAILURE ||
	    dtrace_register("lockstat", &lockstat_attr, DTRACE_PRIV_KERNEL,
	    NULL, &lockstat_pops, NULL, &lockstat_id) != 0) {
		ddi_remove_minor_node(devi, NULL);
		return (DDI_FAILURE);
	}

	lockstat_probe = dtrace_probe;
	membar_producer();

	ddi_report_dev(devi);
	lockstat_devi = devi;
	return (DDI_SUCCESS);
}

d_open_t _lockstat_open;

int _lockstat_open(dev_t dev, int flags, int devtype, struct proc *p)
{
#pragma unused(dev,flags,devtype,p)
	return 0;
}

#define LOCKSTAT_MAJOR  -24 /* let the kernel pick the device number */

/*
 * A struct describing which functions will get invoked for certain
 * actions.
 */
static struct cdevsw lockstat_cdevsw =
{
	_lockstat_open,		/* open */
	eno_opcl,			/* close */
	eno_rdwrt,			/* read */
	eno_rdwrt,			/* write */
	eno_ioctl,			/* ioctl */
	(stop_fcn_t *)nulldev, /* stop */
	(reset_fcn_t *)nulldev, /* reset */
	NULL,				/* tty's */
	eno_select,			/* select */
	eno_mmap,			/* mmap */
	eno_strat,			/* strategy */
	eno_getc,			/* getc */
	eno_putc,			/* putc */
	0					/* type */
};

static int gLockstatInited = 0;

void lockstat_init( void );

void lockstat_init( void )
{
	if (0 == gLockstatInited)
	{
		int majdevno = cdevsw_add(LOCKSTAT_MAJOR, &lockstat_cdevsw);
		
		if (majdevno < 0) {
			printf("lockstat_init: failed to allocate a major number!\n");
			gLockstatInited = 0;
			return;
		}

		lockstat_attach( (dev_info_t	*)(uintptr_t)majdevno, DDI_ATTACH );
		gLockstatInited = 1;
	} else
		panic("lockstat_init: called twice!\n");
}
#undef LOCKSTAT_MAJOR
Commit	Line	Data
2d21ac55 A	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	/*
6d2010ae	22	* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
2d21ac55 A	23	* Use is subject to license terms.
	24	*/
	25
b0d623f7	26	/* #pragma ident "@(#)lockstat.c 1.12 08/01/16 SMI" */
2d21ac55 A	27
	28
	29	#ifdef KERNEL
	30	#ifndef _KERNEL
	31	#define _KERNEL /* Solaris vs. Darwin */
	32	#endif
	33	#endif
	34
	35	#include <sys/param.h>
	36	#include <sys/systm.h>
	37	#include <sys/errno.h>
	38	#include <sys/stat.h>
	39	#include <sys/ioctl.h>
	40	#include <sys/conf.h>
	41	#include <sys/fcntl.h>
	42	#include <miscfs/devfs/devfs.h>
	43
	44	#include <sys/dtrace.h>
	45	#include <sys/dtrace_impl.h>
	46
	47	#include <sys/dtrace_glue.h>
	48
	49	#include <sys/lockstat.h>
	50
	51	#include <kern/processor.h>
	52
	53	#define membar_producer dtrace_membar_producer
	54
	55	/*
	56	* Hot patch values, x86
	57	*/
b0d623f7	58	#if defined(__i386__) \|\| defined(__x86_64__)
2d21ac55 A	59	#define NOP 0x90
	60	#define RET 0xc3
	61	#define LOCKSTAT_AFRAMES 1
2d21ac55 A	62	#else
	63	#error "not ported to this architecture"
	64	#endif
	65
	66
	67	typedef struct lockstat_probe {
	68	const char *lsp_func;
	69	const char *lsp_name;
	70	int lsp_probe;
	71	dtrace_id_t lsp_id;
	72	} lockstat_probe_t;
	73
	74	lockstat_probe_t lockstat_probes[] =
	75	{
b0d623f7	76	#if defined(__i386__) \|\| defined(__x86_64__)
2d21ac55 A	77	/* Not implemented yet on PPC... */
	78	{ LS_LCK_MTX_LOCK, LSA_ACQUIRE, LS_LCK_MTX_LOCK_ACQUIRE, DTRACE_IDNONE },
	79	{ LS_LCK_MTX_LOCK, LSA_SPIN, LS_LCK_MTX_LOCK_SPIN, DTRACE_IDNONE },
	80	{ LS_LCK_MTX_TRY_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_LOCK_ACQUIRE, DTRACE_IDNONE },
	81	{ LS_LCK_MTX_TRY_SPIN_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_SPIN_LOCK_ACQUIRE, DTRACE_IDNONE },
	82	{ LS_LCK_MTX_UNLOCK, LSA_RELEASE, LS_LCK_MTX_UNLOCK_RELEASE, DTRACE_IDNONE },
	83	{ LS_LCK_MTX_EXT_LOCK, LSA_ACQUIRE, LS_LCK_MTX_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },
	84	{ LS_LCK_MTX_EXT_LOCK, LSA_SPIN, LS_LCK_MTX_EXT_LOCK_SPIN, DTRACE_IDNONE },
	85	{ LS_LCK_MTX_EXT_TRY_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },
	86	{ LS_LCK_MTX_UNLOCK, LSA_RELEASE, LS_LCK_MTX_EXT_UNLOCK_RELEASE, DTRACE_IDNONE },
b0d623f7	87	{ LS_LCK_MTX_LOCK_SPIN_LOCK, LSA_ACQUIRE, LS_LCK_MTX_LOCK_SPIN_ACQUIRE, DTRACE_IDNONE },
2d21ac55 A	88	#endif
	89	{ LS_LCK_MTX_LOCK, LSA_BLOCK, LS_LCK_MTX_LOCK_BLOCK, DTRACE_IDNONE },
	90	{ LS_LCK_MTX_EXT_LOCK, LSA_BLOCK, LS_LCK_MTX_EXT_LOCK_BLOCK, DTRACE_IDNONE },
	91
2d21ac55 A	92	{ LS_LCK_RW_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	93	{ LS_LCK_RW_LOCK_SHARED, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_BLOCK, DTRACE_IDNONE },
	94	{ LS_LCK_RW_LOCK_SHARED, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_SPIN, DTRACE_IDNONE },
	95	{ LS_LCK_RW_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	96	{ LS_LCK_RW_LOCK_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_EXCL_BLOCK, DTRACE_IDNONE },
	97	{ LS_LCK_RW_LOCK_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_EXCL_SPIN, DTRACE_IDNONE },
	98	{ LS_LCK_RW_DONE, LSR_RELEASE, LS_LCK_RW_DONE_RELEASE, DTRACE_IDNONE },
	99	{ LS_LCK_RW_TRY_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	100	{ LS_LCK_RW_TRY_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	101	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_UPGRADE, LS_LCK_RW_LOCK_SHARED_TO_EXCL_UPGRADE, DTRACE_IDNONE },
	102	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_TO_EXCL_BLOCK, DTRACE_IDNONE },
	103	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN, DTRACE_IDNONE },
	104	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED, LSR_DOWNGRADE, LS_LCK_RW_LOCK_EXCL_TO_SHARED_DOWNGRADE, DTRACE_IDNONE },
	105
	106
	107	#ifdef LATER
	108	/* Interlock and spinlock measurements would be nice, but later */
	109	{ LS_LCK_SPIN_LOCK, LSS_ACQUIRE, LS_LCK_SPIN_LOCK_ACQUIRE, DTRACE_IDNONE },
	110	{ LS_LCK_SPIN_LOCK, LSS_SPIN, LS_LCK_SPIN_LOCK_SPIN, DTRACE_IDNONE },
	111	{ LS_LCK_SPIN_UNLOCK, LSS_RELEASE, LS_LCK_SPIN_UNLOCK_RELEASE, DTRACE_IDNONE },
	112
	113	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED, LSA_ILK_SPIN, LS_LCK_RW_LOCK_EXCL_TO_SHARED_ILK_SPIN, DTRACE_IDNONE },
	114	{ LS_LCK_MTX_LOCK, LSA_ILK_SPIN, LS_LCK_MTX_LOCK_ILK_SPIN, DTRACE_IDNONE },
	115	{ LS_LCK_MTX_EXT_LOCK, LSA_ILK_SPIN, LS_LCK_MTX_EXT_LOCK_ILK_SPIN, DTRACE_IDNONE },
	116	{ LS_LCK_RW_TRY_LOCK_EXCL, LSA_ILK_SPIN, LS_LCK_RW_TRY_LOCK_EXCL_ILK_SPIN, DTRACE_IDNONE },
	117	{ LS_LCK_RW_TRY_LOCK_SHARED, LSA_SPIN, LS_LCK_RW_TRY_LOCK_SHARED_SPIN, DTRACE_IDNONE },
	118	#endif
	119
b0d623f7	120	{ NULL, NULL, 0, 0 }
2d21ac55 A	121	};
	122
	123	dtrace_id_t lockstat_probemap[LS_NPROBES];
	124
b0d623f7 A	125	#if CONFIG_DTRACE
	126	extern void lck_mtx_lock_lockstat_patch_point(void);
	127	extern void lck_mtx_try_lock_lockstat_patch_point(void);
	128	extern void lck_mtx_try_lock_spin_lockstat_patch_point(void);
	129	extern void lck_mtx_unlock_lockstat_patch_point(void);
	130	extern void lck_mtx_lock_ext_lockstat_patch_point(void);
	131	extern void lck_mtx_ext_unlock_lockstat_patch_point(void);
	132
	133	extern void lck_rw_lock_shared_lockstat_patch_point(void);
	134	extern void lck_rw_lock_exclusive_lockstat_patch_point(void);
	135	extern void lck_rw_lock_shared_to_exclusive_lockstat_patch_point(void);
	136	extern void lck_rw_try_lock_shared_lockstat_patch_point(void);
	137	extern void lck_rw_try_lock_exclusive_lockstat_patch_point(void);
	138	extern void lck_mtx_lock_spin_lockstat_patch_point(void);
	139	#endif /* CONFIG_DTRACE */
2d21ac55 A	140
2d21ac55 A	141	vm_offset_t *assembly_probes[] = {
b0d623f7 A	142	#if CONFIG_DTRACE
b0d623f7 A	143	#if defined(__i386__) \|\| defined(__x86_64__)
2d21ac55 A	144	/*
	145	* On x86 these points are better done via hot patches, which ensure
	146	* there is zero overhead when not in use. On x86 these patch points
	147	* are swapped between the return instruction and a no-op, with the
	148	* Dtrace call following the return.
	149	*/
	150	(vm_offset_t *) lck_mtx_lock_lockstat_patch_point,
	151	(vm_offset_t *) lck_mtx_try_lock_lockstat_patch_point,
	152	(vm_offset_t *) lck_mtx_try_lock_spin_lockstat_patch_point,
	153	(vm_offset_t *) lck_mtx_unlock_lockstat_patch_point,
2d21ac55 A	154	(vm_offset_t *) lck_mtx_lock_ext_lockstat_patch_point,
2d21ac55 A	155	(vm_offset_t *) lck_mtx_ext_unlock_lockstat_patch_point,
b0d623f7 A	156	(vm_offset_t *) lck_rw_lock_shared_lockstat_patch_point,
	157	(vm_offset_t *) lck_rw_lock_exclusive_lockstat_patch_point,
	158	(vm_offset_t *) lck_rw_lock_shared_to_exclusive_lockstat_patch_point,
	159	(vm_offset_t *) lck_rw_try_lock_shared_lockstat_patch_point,
	160	(vm_offset_t *) lck_rw_try_lock_exclusive_lockstat_patch_point,
	161	(vm_offset_t *) lck_mtx_lock_spin_lockstat_patch_point,
	162	#else
2d21ac55	163	(vm_offset_t *) lck_mtx_unlock_lockstat_patch_point,
b0d623f7 A	164	#endif
b0d623f7 A	165	#endif /* CONFIG_DTRACE */
2d21ac55 A	166	NULL
	167	};
	168	/*
	169	* Hot patch switches back and forth the probe points between NOP and RET.
	170	* The argument indicates whether the probe point is on or off.
	171	*/
b0d623f7 A	172	#if defined(__APPLE__)
	173	static
	174	#endif /* __APPLE__ */
2d21ac55 A	175	void lockstat_hot_patch(boolean_t active)
2d21ac55 A	176	{
c910b4d9	177	#pragma unused(active)
2d21ac55 A	178	int i;
	179
	180
	181	for (i = 0; assembly_probes[i]; i++) {
b0d623f7	182	#if defined(__i386__) \|\| defined(__x86_64__)
2d21ac55 A	183	uint8_t instr;
	184	instr = (active ? NOP : RET );
	185	(void) ml_nofault_copy( (vm_offset_t)&instr, *(assembly_probes[i]),
	186	sizeof(instr));
2d21ac55 A	187	#endif
	188	}
	189	}
	190
	191
	192
	193	void (*lockstat_probe)(dtrace_id_t, uint64_t, uint64_t,
	194	uint64_t, uint64_t, uint64_t);
	195
2d21ac55 A	196	static dev_info_t lockstat_devi; / saved in xxattach() for xxinfo() */
	197	static dtrace_provider_id_t lockstat_id;
	198
	199	/ARGSUSED/
6d2010ae	200	static int
2d21ac55 A	201	lockstat_enable(void arg, dtrace_id_t id, void parg)
2d21ac55 A	202	{
b0d623f7 A	203	#pragma unused(arg) /* __APPLE__ */
b0d623f7 A	204
2d21ac55 A	205	lockstat_probe_t *probe = parg;
	206
	207	ASSERT(!lockstat_probemap[probe->lsp_probe]);
	208
	209	lockstat_probemap[probe->lsp_probe] = id;
	210	membar_producer();
	211
2d21ac55 A	212	lockstat_hot_patch(TRUE);
2d21ac55 A	213	membar_producer();
6d2010ae	214	return(0);
2d21ac55 A	215
	216	}
	217
	218	/ARGSUSED/
	219	static void
	220	lockstat_disable(void arg, dtrace_id_t id, void parg)
	221	{
b0d623f7 A	222	#pragma unused(arg, id) /* __APPLE__ */
b0d623f7 A	223
2d21ac55 A	224	lockstat_probe_t *probe = parg;
	225	int i;
	226
	227	ASSERT(lockstat_probemap[probe->lsp_probe]);
	228
	229	lockstat_probemap[probe->lsp_probe] = 0;
	230	lockstat_hot_patch(FALSE);
	231	membar_producer();
	232
	233	/*
	234	* See if we have any probes left enabled.
	235	*/
	236	for (i = 0; i < LS_NPROBES; i++) {
	237	if (lockstat_probemap[i]) {
	238	/*
	239	* This probe is still enabled. We don't need to deal
	240	* with waiting for all threads to be out of the
	241	* lockstat critical sections; just return.
	242	*/
	243	return;
	244	}
	245	}
	246
	247	}
	248
	249	/ARGSUSED/
	250	static void
	251	lockstat_provide(void arg, const dtrace_probedesc_t desc)
	252	{
b0d623f7 A	253	#pragma unused(arg, desc) /* __APPLE__ */
b0d623f7 A	254
2d21ac55 A	255	int i = 0;
	256
	257	for (i = 0; lockstat_probes[i].lsp_func != NULL; i++) {
	258	lockstat_probe_t *probe = &lockstat_probes[i];
	259
	260	if (dtrace_probe_lookup(lockstat_id, "mach_kernel",
	261	probe->lsp_func, probe->lsp_name) != 0)
	262	continue;
	263
	264	ASSERT(!probe->lsp_id);
	265	probe->lsp_id = dtrace_probe_create(lockstat_id,
	266	"mach_kernel", probe->lsp_func, probe->lsp_name,
	267	LOCKSTAT_AFRAMES, probe);
	268	}
	269	}
	270
	271
	272	/ARGSUSED/
	273	static void
	274	lockstat_destroy(void arg, dtrace_id_t id, void parg)
	275	{
b0d623f7 A	276	#pragma unused(arg, id) /* __APPLE__ */
b0d623f7 A	277
2d21ac55 A	278	lockstat_probe_t *probe = parg;
	279
	280	ASSERT(!lockstat_probemap[probe->lsp_probe]);
	281	probe->lsp_id = 0;
	282	}
	283
	284	static dtrace_pattr_t lockstat_attr = {
	285	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	286	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
	287	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
	288	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	289	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	290	};
	291
	292	static dtrace_pops_t lockstat_pops = {
	293	lockstat_provide,
	294	NULL,
	295	lockstat_enable,
	296	lockstat_disable,
	297	NULL,
	298	NULL,
	299	NULL,
	300	NULL,
	301	NULL,
	302	lockstat_destroy
	303	};
	304
	305	static int
	306	lockstat_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
	307	{
	308	switch (cmd) {
	309	case DDI_ATTACH:
	310	break;
	311	case DDI_RESUME:
	312	return (DDI_SUCCESS);
	313	default:
	314	return (DDI_FAILURE);
	315	}
	316
	317	if (ddi_create_minor_node(devi, "lockstat", S_IFCHR, 0,
	318	DDI_PSEUDO, 0) == DDI_FAILURE \|\|
	319	dtrace_register("lockstat", &lockstat_attr, DTRACE_PRIV_KERNEL,
	320	NULL, &lockstat_pops, NULL, &lockstat_id) != 0) {
	321	ddi_remove_minor_node(devi, NULL);
	322	return (DDI_FAILURE);
	323	}
	324
b0d623f7 A	325	lockstat_probe = dtrace_probe;
	326	membar_producer();
	327
2d21ac55 A	328	ddi_report_dev(devi);
2d21ac55 A	329	lockstat_devi = devi;
2d21ac55 A	330	return (DDI_SUCCESS);
	331	}
	332
	333	d_open_t _lockstat_open;
	334
	335	int _lockstat_open(dev_t dev, int flags, int devtype, struct proc *p)
	336	{
	337	#pragma unused(dev,flags,devtype,p)
	338	return 0;
	339	}
	340
	341	#define LOCKSTAT_MAJOR -24 /* let the kernel pick the device number */
	342
	343	/*
	344	* A struct describing which functions will get invoked for certain
	345	* actions.
	346	*/
	347	static struct cdevsw lockstat_cdevsw =
	348	{
	349	_lockstat_open, /* open */
	350	eno_opcl, /* close */
	351	eno_rdwrt, /* read */
	352	eno_rdwrt, /* write */
	353	eno_ioctl, /* ioctl */
	354	(stop_fcn_t )nulldev, / stop */
	355	(reset_fcn_t )nulldev, / reset */
	356	NULL, /* tty's */
	357	eno_select, /* select */
	358	eno_mmap, /* mmap */
	359	eno_strat, /* strategy */
	360	eno_getc, /* getc */
	361	eno_putc, /* putc */
	362	0 /* type */
	363	};
	364
	365	static int gLockstatInited = 0;
	366
	367	void lockstat_init( void );
	368
	369	void lockstat_init( void )
	370	{
	371	if (0 == gLockstatInited)
	372	{
	373	int majdevno = cdevsw_add(LOCKSTAT_MAJOR, &lockstat_cdevsw);
	374
	375	if (majdevno < 0) {
	376	printf("lockstat_init: failed to allocate a major number!\n");
	377	gLockstatInited = 0;
	378	return;
	379	}
	380
b0d623f7	381	lockstat_attach( (dev_info_t *)(uintptr_t)majdevno, DDI_ATTACH );
2d21ac55 A	382	gLockstatInited = 1;
	383	} else
	384	panic("lockstat_init: called twice!\n");
	385	}
	386	#undef LOCKSTAT_MAJOR