[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(__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(__x86_64__)
	/* Only provide implemented probes for each architecture  */
	{ 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_LOCK,	LSA_BLOCK,	LS_LCK_MTX_LOCK_BLOCK, 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_LOCK,	LSA_BLOCK,	LS_LCK_MTX_EXT_LOCK_BLOCK, DTRACE_IDNONE },
//	{ LS_LCK_MTX_EXT_TRY_LOCK, LSA_ACQUIRE,	LS_LCK_MTX_TRY_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },	
	{ LS_LCK_MTX_EXT_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 },
	{ 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_SPIN,	LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN, 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_EXCL_TO_SHARED,	LSR_DOWNGRADE,	LS_LCK_RW_LOCK_EXCL_TO_SHARED_DOWNGRADE, DTRACE_IDNONE },
#endif
#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
#if defined(__x86_64__)
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

#endif /* CONFIG_DTRACE */

typedef struct lockstat_assembly_probe {
	int lsap_probe;
	vm_offset_t * lsap_patch_point;
} lockstat_assembly_probe_t;
	

	lockstat_assembly_probe_t assembly_probes[] =
	{
#if CONFIG_DTRACE
#if 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.
		 */ 
		{ LS_LCK_MTX_LOCK_ACQUIRE,		(vm_offset_t *) lck_mtx_lock_lockstat_patch_point },
		{ LS_LCK_MTX_TRY_LOCK_ACQUIRE,		(vm_offset_t *) lck_mtx_try_lock_lockstat_patch_point },
		{ LS_LCK_MTX_TRY_SPIN_LOCK_ACQUIRE,	(vm_offset_t *) lck_mtx_try_lock_spin_lockstat_patch_point },
		{ LS_LCK_MTX_UNLOCK_RELEASE,		(vm_offset_t *) lck_mtx_unlock_lockstat_patch_point },
		{ LS_LCK_MTX_EXT_LOCK_ACQUIRE,		(vm_offset_t *) lck_mtx_lock_ext_lockstat_patch_point },
		{ LS_LCK_MTX_EXT_UNLOCK_RELEASE,	(vm_offset_t *) lck_mtx_ext_unlock_lockstat_patch_point },
		{ LS_LCK_RW_LOCK_SHARED_ACQUIRE,	(vm_offset_t *) lck_rw_lock_shared_lockstat_patch_point },
		{ LS_LCK_RW_LOCK_EXCL_ACQUIRE,		(vm_offset_t *) lck_rw_lock_exclusive_lockstat_patch_point },
		{ LS_LCK_RW_LOCK_SHARED_TO_EXCL_UPGRADE,(vm_offset_t *) lck_rw_lock_shared_to_exclusive_lockstat_patch_point },
		{ LS_LCK_RW_TRY_LOCK_SHARED_ACQUIRE,	(vm_offset_t *) lck_rw_try_lock_shared_lockstat_patch_point },
		{ LS_LCK_RW_TRY_LOCK_EXCL_ACQUIRE,	(vm_offset_t *) lck_rw_try_lock_exclusive_lockstat_patch_point },
		{ LS_LCK_MTX_LOCK_SPIN_ACQUIRE,		(vm_offset_t *) lck_mtx_lock_spin_lockstat_patch_point },
#endif
		/* No assembly patch points for ARM */
#endif /* CONFIG_DTRACE */
		{ LS_LCK_INVALID, NULL }
};


/*
 * APPLE NOTE:
 * Hot patch is used to manipulate probe points by swapping between
 * no-op and return instructions.
 * The active flag indicates whether the probe point will turn on or off.
 *	on == plant a NOP and thus fall through to the probe call
 *     off == plant a RET and thus avoid the probe call completely
 * The ls_probe identifies which probe we will patch.
 */
static
void lockstat_hot_patch(boolean_t active, int ls_probe)
{
#pragma unused(active)
	int i;

	/*
	 * Loop through entire table, in case there are
	 * multiple patch points per probe. 
	 */
	for (i = 0; assembly_probes[i].lsap_patch_point; i++) {
		if (ls_probe == assembly_probes[i].lsap_probe)
#if defined(__x86_64__)
		{			
			uint8_t instr;
			instr = (active ? NOP : RET );
			(void) ml_nofault_copy( (vm_offset_t)&instr, *(assembly_probes[i].lsap_patch_point), 
								sizeof(instr));
		}
#endif
	} /* for */
}

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


/*
 * APPLE NOTE:
 * This wrapper is used only by assembler hot patched probes.
 */
void
lockstat_probe_wrapper(int probe, uintptr_t lp, int rwflag)
{
	dtrace_id_t id;
	id = lockstat_probemap[probe];
	if (id != 0)
	{
		(*lockstat_probe)(id, (uintptr_t)lp, (uint64_t)rwflag, 0,0,0);
	}
}

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, probe->lsp_probe);
	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, probe->lsp_probe);
	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	*/
39236c6e	58	#if 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
2d21ac55 A	66	typedef struct lockstat_probe {
	67	const char *lsp_func;
	68	const char *lsp_name;
	69	int lsp_probe;
	70	dtrace_id_t lsp_id;
	71	} lockstat_probe_t;
	72
	73	lockstat_probe_t lockstat_probes[] =
	74	{
39236c6e	75	#if defined(__x86_64__)
316670eb	76	/* Only provide implemented probes for each architecture */
2d21ac55 A	77	{ LS_LCK_MTX_LOCK, LSA_ACQUIRE, LS_LCK_MTX_LOCK_ACQUIRE, DTRACE_IDNONE },
2d21ac55 A	78	{ LS_LCK_MTX_LOCK, LSA_SPIN, LS_LCK_MTX_LOCK_SPIN, DTRACE_IDNONE },
316670eb	79	{ LS_LCK_MTX_LOCK, LSA_BLOCK, LS_LCK_MTX_LOCK_BLOCK, DTRACE_IDNONE },
2d21ac55 A	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 },
2d21ac55	85	{ LS_LCK_MTX_EXT_LOCK, LSA_BLOCK, LS_LCK_MTX_EXT_LOCK_BLOCK, DTRACE_IDNONE },
316670eb A	86	// { LS_LCK_MTX_EXT_TRY_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },
	87	{ LS_LCK_MTX_EXT_UNLOCK, LSA_RELEASE, LS_LCK_MTX_EXT_UNLOCK_RELEASE, DTRACE_IDNONE },
	88	{ LS_LCK_MTX_LOCK_SPIN_LOCK, LSA_ACQUIRE, LS_LCK_MTX_LOCK_SPIN_ACQUIRE, DTRACE_IDNONE },
2d21ac55 A	89	{ LS_LCK_RW_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	90	{ LS_LCK_RW_LOCK_SHARED, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_BLOCK, DTRACE_IDNONE },
	91	{ LS_LCK_RW_LOCK_SHARED, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_SPIN, DTRACE_IDNONE },
	92	{ LS_LCK_RW_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	93	{ LS_LCK_RW_LOCK_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_EXCL_BLOCK, DTRACE_IDNONE },
	94	{ LS_LCK_RW_LOCK_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_EXCL_SPIN, DTRACE_IDNONE },
	95	{ LS_LCK_RW_DONE, LSR_RELEASE, LS_LCK_RW_DONE_RELEASE, DTRACE_IDNONE },
	96	{ LS_LCK_RW_TRY_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	97	{ LS_LCK_RW_TRY_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	98	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_UPGRADE, LS_LCK_RW_LOCK_SHARED_TO_EXCL_UPGRADE, DTRACE_IDNONE },
2d21ac55	99	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN, DTRACE_IDNONE },
316670eb	100	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_TO_EXCL_BLOCK, DTRACE_IDNONE },
2d21ac55	101	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED, LSR_DOWNGRADE, LS_LCK_RW_LOCK_EXCL_TO_SHARED_DOWNGRADE, DTRACE_IDNONE },
316670eb	102	#endif
2d21ac55 A	103	#ifdef LATER
	104	/* Interlock and spinlock measurements would be nice, but later */
	105	{ LS_LCK_SPIN_LOCK, LSS_ACQUIRE, LS_LCK_SPIN_LOCK_ACQUIRE, DTRACE_IDNONE },
	106	{ LS_LCK_SPIN_LOCK, LSS_SPIN, LS_LCK_SPIN_LOCK_SPIN, DTRACE_IDNONE },
	107	{ LS_LCK_SPIN_UNLOCK, LSS_RELEASE, LS_LCK_SPIN_UNLOCK_RELEASE, DTRACE_IDNONE },
	108
	109	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED, LSA_ILK_SPIN, LS_LCK_RW_LOCK_EXCL_TO_SHARED_ILK_SPIN, DTRACE_IDNONE },
	110	{ LS_LCK_MTX_LOCK, LSA_ILK_SPIN, LS_LCK_MTX_LOCK_ILK_SPIN, DTRACE_IDNONE },
	111	{ LS_LCK_MTX_EXT_LOCK, LSA_ILK_SPIN, LS_LCK_MTX_EXT_LOCK_ILK_SPIN, DTRACE_IDNONE },
	112	{ LS_LCK_RW_TRY_LOCK_EXCL, LSA_ILK_SPIN, LS_LCK_RW_TRY_LOCK_EXCL_ILK_SPIN, DTRACE_IDNONE },
	113	{ LS_LCK_RW_TRY_LOCK_SHARED, LSA_SPIN, LS_LCK_RW_TRY_LOCK_SHARED_SPIN, DTRACE_IDNONE },
	114	#endif
	115
b0d623f7	116	{ NULL, NULL, 0, 0 }
2d21ac55 A	117	};
	118
	119	dtrace_id_t lockstat_probemap[LS_NPROBES];
	120
b0d623f7	121	#if CONFIG_DTRACE
39236c6e	122	#if defined(__x86_64__)
b0d623f7 A	123	extern void lck_mtx_lock_lockstat_patch_point(void);
	124	extern void lck_mtx_try_lock_lockstat_patch_point(void);
	125	extern void lck_mtx_try_lock_spin_lockstat_patch_point(void);
	126	extern void lck_mtx_unlock_lockstat_patch_point(void);
	127	extern void lck_mtx_lock_ext_lockstat_patch_point(void);
	128	extern void lck_mtx_ext_unlock_lockstat_patch_point(void);
b0d623f7 A	129	extern void lck_rw_lock_shared_lockstat_patch_point(void);
	130	extern void lck_rw_lock_exclusive_lockstat_patch_point(void);
	131	extern void lck_rw_lock_shared_to_exclusive_lockstat_patch_point(void);
	132	extern void lck_rw_try_lock_shared_lockstat_patch_point(void);
	133	extern void lck_rw_try_lock_exclusive_lockstat_patch_point(void);
	134	extern void lck_mtx_lock_spin_lockstat_patch_point(void);
39236c6e A	135	#endif
39236c6e A	136
b0d623f7	137	#endif /* CONFIG_DTRACE */
2d21ac55	138
316670eb A	139	typedef struct lockstat_assembly_probe {
	140	int lsap_probe;
	141	vm_offset_t * lsap_patch_point;
	142	} lockstat_assembly_probe_t;
	143
	144
	145	lockstat_assembly_probe_t assembly_probes[] =
	146	{
b0d623f7	147	#if CONFIG_DTRACE
39236c6e	148	#if defined(__x86_64__)
316670eb A	149	/*
	150	* On x86 these points are better done via hot patches, which ensure
	151	* there is zero overhead when not in use. On x86 these patch points
	152	* are swapped between the return instruction and a no-op, with the
	153	* Dtrace call following the return.
	154	*/
	155	{ LS_LCK_MTX_LOCK_ACQUIRE, (vm_offset_t *) lck_mtx_lock_lockstat_patch_point },
	156	{ LS_LCK_MTX_TRY_LOCK_ACQUIRE, (vm_offset_t *) lck_mtx_try_lock_lockstat_patch_point },
	157	{ LS_LCK_MTX_TRY_SPIN_LOCK_ACQUIRE, (vm_offset_t *) lck_mtx_try_lock_spin_lockstat_patch_point },
	158	{ LS_LCK_MTX_UNLOCK_RELEASE, (vm_offset_t *) lck_mtx_unlock_lockstat_patch_point },
	159	{ LS_LCK_MTX_EXT_LOCK_ACQUIRE, (vm_offset_t *) lck_mtx_lock_ext_lockstat_patch_point },
	160	{ LS_LCK_MTX_EXT_UNLOCK_RELEASE, (vm_offset_t *) lck_mtx_ext_unlock_lockstat_patch_point },
	161	{ LS_LCK_RW_LOCK_SHARED_ACQUIRE, (vm_offset_t *) lck_rw_lock_shared_lockstat_patch_point },
	162	{ LS_LCK_RW_LOCK_EXCL_ACQUIRE, (vm_offset_t *) lck_rw_lock_exclusive_lockstat_patch_point },
	163	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL_UPGRADE,(vm_offset_t *) lck_rw_lock_shared_to_exclusive_lockstat_patch_point },
	164	{ LS_LCK_RW_TRY_LOCK_SHARED_ACQUIRE, (vm_offset_t *) lck_rw_try_lock_shared_lockstat_patch_point },
	165	{ LS_LCK_RW_TRY_LOCK_EXCL_ACQUIRE, (vm_offset_t *) lck_rw_try_lock_exclusive_lockstat_patch_point },
	166	{ LS_LCK_MTX_LOCK_SPIN_ACQUIRE, (vm_offset_t *) lck_mtx_lock_spin_lockstat_patch_point },
b0d623f7	167	#endif
3e170ce0	168	/* No assembly patch points for ARM */
b0d623f7	169	#endif /* CONFIG_DTRACE */
316670eb	170	{ LS_LCK_INVALID, NULL }
2d21ac55	171	};
39236c6e A	172
39236c6e A	173
2d21ac55	174	/*
fe8ab488 A	175	* APPLE NOTE:
	176	* Hot patch is used to manipulate probe points by swapping between
	177	* no-op and return instructions.
	178	* The active flag indicates whether the probe point will turn on or off.
316670eb A	179	* on == plant a NOP and thus fall through to the probe call
316670eb A	180	* off == plant a RET and thus avoid the probe call completely
fe8ab488	181	* The ls_probe identifies which probe we will patch.
2d21ac55	182	*/
b0d623f7	183	static
316670eb	184	void lockstat_hot_patch(boolean_t active, int ls_probe)
2d21ac55	185	{
c910b4d9	186	#pragma unused(active)
2d21ac55 A	187	int i;
2d21ac55 A	188
316670eb A	189	/*
	190	* Loop through entire table, in case there are
	191	* multiple patch points per probe.
	192	*/
	193	for (i = 0; assembly_probes[i].lsap_patch_point; i++) {
	194	if (ls_probe == assembly_probes[i].lsap_probe)
39236c6e	195	#if defined(__x86_64__)
316670eb A	196	{
	197	uint8_t instr;
	198	instr = (active ? NOP : RET );
	199	(void) ml_nofault_copy( (vm_offset_t)&instr, *(assembly_probes[i].lsap_patch_point),
2d21ac55	200	sizeof(instr));
316670eb	201	}
2d21ac55	202	#endif
316670eb	203	} /* for */
2d21ac55	204	}
2d21ac55 A	205
	206	void (*lockstat_probe)(dtrace_id_t, uint64_t, uint64_t,
	207	uint64_t, uint64_t, uint64_t);
	208
fe8ab488 A	209
	210	/*
	211	* APPLE NOTE:
	212	* This wrapper is used only by assembler hot patched probes.
	213	*/
316670eb A	214	void
	215	lockstat_probe_wrapper(int probe, uintptr_t lp, int rwflag)
	216	{
	217	dtrace_id_t id;
	218	id = lockstat_probemap[probe];
	219	if (id != 0)
	220	{
	221	(*lockstat_probe)(id, (uintptr_t)lp, (uint64_t)rwflag, 0,0,0);
	222	}
	223	}
316670eb	224
2d21ac55 A	225	static dev_info_t lockstat_devi; / saved in xxattach() for xxinfo() */
	226	static dtrace_provider_id_t lockstat_id;
	227
	228	/ARGSUSED/
6d2010ae	229	static int
2d21ac55 A	230	lockstat_enable(void arg, dtrace_id_t id, void parg)
2d21ac55 A	231	{
b0d623f7 A	232	#pragma unused(arg) /* __APPLE__ */
b0d623f7 A	233
2d21ac55 A	234	lockstat_probe_t *probe = parg;
	235
	236	ASSERT(!lockstat_probemap[probe->lsp_probe]);
	237
	238	lockstat_probemap[probe->lsp_probe] = id;
	239	membar_producer();
	240
316670eb	241	lockstat_hot_patch(TRUE, probe->lsp_probe);
2d21ac55	242	membar_producer();
6d2010ae	243	return(0);
2d21ac55 A	244
	245	}
	246
	247	/ARGSUSED/
	248	static void
	249	lockstat_disable(void arg, dtrace_id_t id, void parg)
	250	{
b0d623f7 A	251	#pragma unused(arg, id) /* __APPLE__ */
b0d623f7 A	252
2d21ac55 A	253	lockstat_probe_t *probe = parg;
	254	int i;
	255
	256	ASSERT(lockstat_probemap[probe->lsp_probe]);
	257
	258	lockstat_probemap[probe->lsp_probe] = 0;
316670eb	259	lockstat_hot_patch(FALSE, probe->lsp_probe);
2d21ac55 A	260	membar_producer();
	261
	262	/*
	263	* See if we have any probes left enabled.
	264	*/
	265	for (i = 0; i < LS_NPROBES; i++) {
	266	if (lockstat_probemap[i]) {
	267	/*
	268	* This probe is still enabled. We don't need to deal
	269	* with waiting for all threads to be out of the
	270	* lockstat critical sections; just return.
	271	*/
	272	return;
	273	}
	274	}
	275
	276	}
	277
	278	/ARGSUSED/
	279	static void
	280	lockstat_provide(void arg, const dtrace_probedesc_t desc)
	281	{
b0d623f7 A	282	#pragma unused(arg, desc) /* __APPLE__ */
b0d623f7 A	283
2d21ac55 A	284	int i = 0;
	285
	286	for (i = 0; lockstat_probes[i].lsp_func != NULL; i++) {
	287	lockstat_probe_t *probe = &lockstat_probes[i];
	288
	289	if (dtrace_probe_lookup(lockstat_id, "mach_kernel",
	290	probe->lsp_func, probe->lsp_name) != 0)
	291	continue;
	292
	293	ASSERT(!probe->lsp_id);
	294	probe->lsp_id = dtrace_probe_create(lockstat_id,
	295	"mach_kernel", probe->lsp_func, probe->lsp_name,
	296	LOCKSTAT_AFRAMES, probe);
	297	}
	298	}
	299
	300
	301	/ARGSUSED/
	302	static void
	303	lockstat_destroy(void arg, dtrace_id_t id, void parg)
	304	{
b0d623f7 A	305	#pragma unused(arg, id) /* __APPLE__ */
b0d623f7 A	306
2d21ac55 A	307	lockstat_probe_t *probe = parg;
	308
	309	ASSERT(!lockstat_probemap[probe->lsp_probe]);
	310	probe->lsp_id = 0;
	311	}
	312
	313	static dtrace_pattr_t lockstat_attr = {
	314	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	315	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
	316	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
	317	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	318	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	319	};
	320
	321	static dtrace_pops_t lockstat_pops = {
	322	lockstat_provide,
	323	NULL,
	324	lockstat_enable,
	325	lockstat_disable,
	326	NULL,
	327	NULL,
	328	NULL,
	329	NULL,
	330	NULL,
	331	lockstat_destroy
	332	};
	333
	334	static int
	335	lockstat_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
	336	{
	337	switch (cmd) {
	338	case DDI_ATTACH:
	339	break;
	340	case DDI_RESUME:
	341	return (DDI_SUCCESS);
	342	default:
	343	return (DDI_FAILURE);
	344	}
	345
	346	if (ddi_create_minor_node(devi, "lockstat", S_IFCHR, 0,
	347	DDI_PSEUDO, 0) == DDI_FAILURE \|\|
	348	dtrace_register("lockstat", &lockstat_attr, DTRACE_PRIV_KERNEL,
	349	NULL, &lockstat_pops, NULL, &lockstat_id) != 0) {
	350	ddi_remove_minor_node(devi, NULL);
	351	return (DDI_FAILURE);
	352	}
	353
b0d623f7 A	354	lockstat_probe = dtrace_probe;
	355	membar_producer();
	356
2d21ac55 A	357	ddi_report_dev(devi);
2d21ac55 A	358	lockstat_devi = devi;
2d21ac55 A	359	return (DDI_SUCCESS);
	360	}
	361
	362	d_open_t _lockstat_open;
	363
	364	int _lockstat_open(dev_t dev, int flags, int devtype, struct proc *p)
	365	{
	366	#pragma unused(dev,flags,devtype,p)
	367	return 0;
	368	}
	369
	370	#define LOCKSTAT_MAJOR -24 /* let the kernel pick the device number */
	371
	372	/*
	373	* A struct describing which functions will get invoked for certain
	374	* actions.
	375	*/
	376	static struct cdevsw lockstat_cdevsw =
	377	{
	378	_lockstat_open, /* open */
	379	eno_opcl, /* close */
	380	eno_rdwrt, /* read */
	381	eno_rdwrt, /* write */
	382	eno_ioctl, /* ioctl */
	383	(stop_fcn_t )nulldev, / stop */
	384	(reset_fcn_t )nulldev, / reset */
	385	NULL, /* tty's */
	386	eno_select, /* select */
	387	eno_mmap, /* mmap */
	388	eno_strat, /* strategy */
	389	eno_getc, /* getc */
	390	eno_putc, /* putc */
	391	0 /* type */
	392	};
	393
	394	static int gLockstatInited = 0;
	395
	396	void lockstat_init( void );
	397
	398	void lockstat_init( void )
	399	{
	400	if (0 == gLockstatInited)
	401	{
	402	int majdevno = cdevsw_add(LOCKSTAT_MAJOR, &lockstat_cdevsw);
	403
	404	if (majdevno < 0) {
	405	printf("lockstat_init: failed to allocate a major number!\n");
	406	gLockstatInited = 0;
	407	return;
	408	}
	409
b0d623f7	410	lockstat_attach( (dev_info_t *)(uintptr_t)majdevno, DDI_ATTACH );
2d21ac55 A	411	gLockstatInited = 1;
	412	} else
	413	panic("lockstat_init: called twice!\n");
	414	}
	415	#undef LOCKSTAT_MAJOR