[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 2008 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
#elif	__ppc__
#define	NOP	0x60000000
#define RET	0x4e800020	/* blr */
#define LOCKSTAT_AFRAMES 2
#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
#ifdef __ppc__
		uint32_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 void
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();

}

/*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	/*
b0d623f7	22	* Copyright 2008 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
	62	#elif __ppc__
	63	#define NOP 0x60000000
	64	#define RET 0x4e800020 /* blr */
	65	#define LOCKSTAT_AFRAMES 2
	66	#else
	67	#error "not ported to this architecture"
	68	#endif
	69
	70
	71	typedef struct lockstat_probe {
	72	const char *lsp_func;
	73	const char *lsp_name;
	74	int lsp_probe;
	75	dtrace_id_t lsp_id;
	76	} lockstat_probe_t;
	77
	78	lockstat_probe_t lockstat_probes[] =
	79	{
b0d623f7	80	#if defined(__i386__) \|\| defined(__x86_64__)
2d21ac55 A	81	/* Not implemented yet on PPC... */
	82	{ LS_LCK_MTX_LOCK, LSA_ACQUIRE, LS_LCK_MTX_LOCK_ACQUIRE, DTRACE_IDNONE },
	83	{ LS_LCK_MTX_LOCK, LSA_SPIN, LS_LCK_MTX_LOCK_SPIN, DTRACE_IDNONE },
	84	{ LS_LCK_MTX_TRY_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_LOCK_ACQUIRE, DTRACE_IDNONE },
	85	{ LS_LCK_MTX_TRY_SPIN_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_SPIN_LOCK_ACQUIRE, DTRACE_IDNONE },
	86	{ LS_LCK_MTX_UNLOCK, LSA_RELEASE, LS_LCK_MTX_UNLOCK_RELEASE, DTRACE_IDNONE },
	87	{ LS_LCK_MTX_EXT_LOCK, LSA_ACQUIRE, LS_LCK_MTX_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },
	88	{ LS_LCK_MTX_EXT_LOCK, LSA_SPIN, LS_LCK_MTX_EXT_LOCK_SPIN, DTRACE_IDNONE },
	89	{ LS_LCK_MTX_EXT_TRY_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_EXT_LOCK_ACQUIRE, DTRACE_IDNONE },
	90	{ LS_LCK_MTX_UNLOCK, LSA_RELEASE, LS_LCK_MTX_EXT_UNLOCK_RELEASE, DTRACE_IDNONE },
b0d623f7	91	{ LS_LCK_MTX_LOCK_SPIN_LOCK, LSA_ACQUIRE, LS_LCK_MTX_LOCK_SPIN_ACQUIRE, DTRACE_IDNONE },
2d21ac55 A	92	#endif
	93	{ LS_LCK_MTX_LOCK, LSA_BLOCK, LS_LCK_MTX_LOCK_BLOCK, DTRACE_IDNONE },
	94	{ LS_LCK_MTX_EXT_LOCK, LSA_BLOCK, LS_LCK_MTX_EXT_LOCK_BLOCK, DTRACE_IDNONE },
	95
2d21ac55 A	96	{ LS_LCK_RW_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	97	{ LS_LCK_RW_LOCK_SHARED, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_BLOCK, DTRACE_IDNONE },
	98	{ LS_LCK_RW_LOCK_SHARED, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_SPIN, DTRACE_IDNONE },
	99	{ LS_LCK_RW_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	100	{ LS_LCK_RW_LOCK_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_EXCL_BLOCK, DTRACE_IDNONE },
	101	{ LS_LCK_RW_LOCK_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_EXCL_SPIN, DTRACE_IDNONE },
	102	{ LS_LCK_RW_DONE, LSR_RELEASE, LS_LCK_RW_DONE_RELEASE, DTRACE_IDNONE },
	103	{ LS_LCK_RW_TRY_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_SHARED_ACQUIRE, DTRACE_IDNONE },
	104	{ LS_LCK_RW_TRY_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_EXCL_ACQUIRE, DTRACE_IDNONE },
	105	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_UPGRADE, LS_LCK_RW_LOCK_SHARED_TO_EXCL_UPGRADE, DTRACE_IDNONE },
	106	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_TO_EXCL_BLOCK, DTRACE_IDNONE },
	107	{ LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN, DTRACE_IDNONE },
	108	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED, LSR_DOWNGRADE, LS_LCK_RW_LOCK_EXCL_TO_SHARED_DOWNGRADE, DTRACE_IDNONE },
	109
	110
	111	#ifdef LATER
	112	/* Interlock and spinlock measurements would be nice, but later */
	113	{ LS_LCK_SPIN_LOCK, LSS_ACQUIRE, LS_LCK_SPIN_LOCK_ACQUIRE, DTRACE_IDNONE },
	114	{ LS_LCK_SPIN_LOCK, LSS_SPIN, LS_LCK_SPIN_LOCK_SPIN, DTRACE_IDNONE },
	115	{ LS_LCK_SPIN_UNLOCK, LSS_RELEASE, LS_LCK_SPIN_UNLOCK_RELEASE, DTRACE_IDNONE },
	116
	117	{ LS_LCK_RW_LOCK_EXCL_TO_SHARED, LSA_ILK_SPIN, LS_LCK_RW_LOCK_EXCL_TO_SHARED_ILK_SPIN, DTRACE_IDNONE },
	118	{ LS_LCK_MTX_LOCK, LSA_ILK_SPIN, LS_LCK_MTX_LOCK_ILK_SPIN, DTRACE_IDNONE },
	119	{ LS_LCK_MTX_EXT_LOCK, LSA_ILK_SPIN, LS_LCK_MTX_EXT_LOCK_ILK_SPIN, DTRACE_IDNONE },
	120	{ LS_LCK_RW_TRY_LOCK_EXCL, LSA_ILK_SPIN, LS_LCK_RW_TRY_LOCK_EXCL_ILK_SPIN, DTRACE_IDNONE },
	121	{ LS_LCK_RW_TRY_LOCK_SHARED, LSA_SPIN, LS_LCK_RW_TRY_LOCK_SHARED_SPIN, DTRACE_IDNONE },
	122	#endif
	123
b0d623f7	124	{ NULL, NULL, 0, 0 }
2d21ac55 A	125	};
	126
	127	dtrace_id_t lockstat_probemap[LS_NPROBES];
	128
b0d623f7 A	129	#if CONFIG_DTRACE
	130	extern void lck_mtx_lock_lockstat_patch_point(void);
	131	extern void lck_mtx_try_lock_lockstat_patch_point(void);
	132	extern void lck_mtx_try_lock_spin_lockstat_patch_point(void);
	133	extern void lck_mtx_unlock_lockstat_patch_point(void);
	134	extern void lck_mtx_lock_ext_lockstat_patch_point(void);
	135	extern void lck_mtx_ext_unlock_lockstat_patch_point(void);
	136
	137	extern void lck_rw_lock_shared_lockstat_patch_point(void);
	138	extern void lck_rw_lock_exclusive_lockstat_patch_point(void);
	139	extern void lck_rw_lock_shared_to_exclusive_lockstat_patch_point(void);
	140	extern void lck_rw_try_lock_shared_lockstat_patch_point(void);
	141	extern void lck_rw_try_lock_exclusive_lockstat_patch_point(void);
	142	extern void lck_mtx_lock_spin_lockstat_patch_point(void);
	143	#endif /* CONFIG_DTRACE */
2d21ac55 A	144
2d21ac55 A	145	vm_offset_t *assembly_probes[] = {
b0d623f7 A	146	#if CONFIG_DTRACE
b0d623f7 A	147	#if defined(__i386__) \|\| defined(__x86_64__)
2d21ac55 A	148	/*
	149	* On x86 these points are better done via hot patches, which ensure
	150	* there is zero overhead when not in use. On x86 these patch points
	151	* are swapped between the return instruction and a no-op, with the
	152	* Dtrace call following the return.
	153	*/
	154	(vm_offset_t *) lck_mtx_lock_lockstat_patch_point,
	155	(vm_offset_t *) lck_mtx_try_lock_lockstat_patch_point,
	156	(vm_offset_t *) lck_mtx_try_lock_spin_lockstat_patch_point,
	157	(vm_offset_t *) lck_mtx_unlock_lockstat_patch_point,
2d21ac55 A	158	(vm_offset_t *) lck_mtx_lock_ext_lockstat_patch_point,
2d21ac55 A	159	(vm_offset_t *) lck_mtx_ext_unlock_lockstat_patch_point,
b0d623f7 A	160	(vm_offset_t *) lck_rw_lock_shared_lockstat_patch_point,
	161	(vm_offset_t *) lck_rw_lock_exclusive_lockstat_patch_point,
	162	(vm_offset_t *) lck_rw_lock_shared_to_exclusive_lockstat_patch_point,
	163	(vm_offset_t *) lck_rw_try_lock_shared_lockstat_patch_point,
	164	(vm_offset_t *) lck_rw_try_lock_exclusive_lockstat_patch_point,
	165	(vm_offset_t *) lck_mtx_lock_spin_lockstat_patch_point,
	166	#else
2d21ac55	167	(vm_offset_t *) lck_mtx_unlock_lockstat_patch_point,
b0d623f7 A	168	#endif
b0d623f7 A	169	#endif /* CONFIG_DTRACE */
2d21ac55 A	170	NULL
	171	};
	172	/*
	173	* Hot patch switches back and forth the probe points between NOP and RET.
	174	* The argument indicates whether the probe point is on or off.
	175	*/
b0d623f7 A	176	#if defined(__APPLE__)
	177	static
	178	#endif /* __APPLE__ */
2d21ac55 A	179	void lockstat_hot_patch(boolean_t active)
2d21ac55 A	180	{
c910b4d9	181	#pragma unused(active)
2d21ac55 A	182	int i;
	183
	184
	185	for (i = 0; assembly_probes[i]; i++) {
b0d623f7	186	#if defined(__i386__) \|\| defined(__x86_64__)
2d21ac55 A	187	uint8_t instr;
	188	instr = (active ? NOP : RET );
	189	(void) ml_nofault_copy( (vm_offset_t)&instr, *(assembly_probes[i]),
	190	sizeof(instr));
	191	#endif
	192	#ifdef __ppc__
	193	uint32_t instr;
	194	instr = (active ? NOP : RET );
	195	(void) ml_nofault_copy( (vm_offset_t)&instr, *(assembly_probes[i]), sizeof(instr));
	196	#endif
	197	}
	198	}
	199
	200
	201
	202	void (*lockstat_probe)(dtrace_id_t, uint64_t, uint64_t,
	203	uint64_t, uint64_t, uint64_t);
	204
2d21ac55 A	205	static dev_info_t lockstat_devi; / saved in xxattach() for xxinfo() */
	206	static dtrace_provider_id_t lockstat_id;
	207
	208	/ARGSUSED/
	209	static void
	210	lockstat_enable(void arg, dtrace_id_t id, void parg)
	211	{
b0d623f7 A	212	#pragma unused(arg) /* __APPLE__ */
b0d623f7 A	213
2d21ac55 A	214	lockstat_probe_t *probe = parg;
	215
	216	ASSERT(!lockstat_probemap[probe->lsp_probe]);
	217
	218	lockstat_probemap[probe->lsp_probe] = id;
	219	membar_producer();
	220
2d21ac55 A	221	lockstat_hot_patch(TRUE);
	222	membar_producer();
	223
	224	}
	225
	226	/ARGSUSED/
	227	static void
	228	lockstat_disable(void arg, dtrace_id_t id, void parg)
	229	{
b0d623f7 A	230	#pragma unused(arg, id) /* __APPLE__ */
b0d623f7 A	231
2d21ac55 A	232	lockstat_probe_t *probe = parg;
	233	int i;
	234
	235	ASSERT(lockstat_probemap[probe->lsp_probe]);
	236
	237	lockstat_probemap[probe->lsp_probe] = 0;
	238	lockstat_hot_patch(FALSE);
	239	membar_producer();
	240
	241	/*
	242	* See if we have any probes left enabled.
	243	*/
	244	for (i = 0; i < LS_NPROBES; i++) {
	245	if (lockstat_probemap[i]) {
	246	/*
	247	* This probe is still enabled. We don't need to deal
	248	* with waiting for all threads to be out of the
	249	* lockstat critical sections; just return.
	250	*/
	251	return;
	252	}
	253	}
	254
	255	}
	256
	257	/ARGSUSED/
	258	static void
	259	lockstat_provide(void arg, const dtrace_probedesc_t desc)
	260	{
b0d623f7 A	261	#pragma unused(arg, desc) /* __APPLE__ */
b0d623f7 A	262
2d21ac55 A	263	int i = 0;
	264
	265	for (i = 0; lockstat_probes[i].lsp_func != NULL; i++) {
	266	lockstat_probe_t *probe = &lockstat_probes[i];
	267
	268	if (dtrace_probe_lookup(lockstat_id, "mach_kernel",
	269	probe->lsp_func, probe->lsp_name) != 0)
	270	continue;
	271
	272	ASSERT(!probe->lsp_id);
	273	probe->lsp_id = dtrace_probe_create(lockstat_id,
	274	"mach_kernel", probe->lsp_func, probe->lsp_name,
	275	LOCKSTAT_AFRAMES, probe);
	276	}
	277	}
	278
	279
	280	/ARGSUSED/
	281	static void
	282	lockstat_destroy(void arg, dtrace_id_t id, void parg)
	283	{
b0d623f7 A	284	#pragma unused(arg, id) /* __APPLE__ */
b0d623f7 A	285
2d21ac55 A	286	lockstat_probe_t *probe = parg;
	287
	288	ASSERT(!lockstat_probemap[probe->lsp_probe]);
	289	probe->lsp_id = 0;
	290	}
	291
	292	static dtrace_pattr_t lockstat_attr = {
	293	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	294	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
	295	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
	296	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	297	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
	298	};
	299
	300	static dtrace_pops_t lockstat_pops = {
	301	lockstat_provide,
	302	NULL,
	303	lockstat_enable,
	304	lockstat_disable,
	305	NULL,
	306	NULL,
	307	NULL,
	308	NULL,
	309	NULL,
	310	lockstat_destroy
	311	};
	312
	313	static int
	314	lockstat_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
	315	{
	316	switch (cmd) {
	317	case DDI_ATTACH:
	318	break;
	319	case DDI_RESUME:
	320	return (DDI_SUCCESS);
	321	default:
	322	return (DDI_FAILURE);
	323	}
	324
	325	if (ddi_create_minor_node(devi, "lockstat", S_IFCHR, 0,
	326	DDI_PSEUDO, 0) == DDI_FAILURE \|\|
	327	dtrace_register("lockstat", &lockstat_attr, DTRACE_PRIV_KERNEL,
	328	NULL, &lockstat_pops, NULL, &lockstat_id) != 0) {
	329	ddi_remove_minor_node(devi, NULL);
	330	return (DDI_FAILURE);
	331	}
	332
b0d623f7 A	333	lockstat_probe = dtrace_probe;
	334	membar_producer();
	335
2d21ac55 A	336	ddi_report_dev(devi);
2d21ac55 A	337	lockstat_devi = devi;
2d21ac55 A	338	return (DDI_SUCCESS);
	339	}
	340
	341	d_open_t _lockstat_open;
	342
	343	int _lockstat_open(dev_t dev, int flags, int devtype, struct proc *p)
	344	{
	345	#pragma unused(dev,flags,devtype,p)
	346	return 0;
	347	}
	348
	349	#define LOCKSTAT_MAJOR -24 /* let the kernel pick the device number */
	350
	351	/*
	352	* A struct describing which functions will get invoked for certain
	353	* actions.
	354	*/
	355	static struct cdevsw lockstat_cdevsw =
	356	{
	357	_lockstat_open, /* open */
	358	eno_opcl, /* close */
	359	eno_rdwrt, /* read */
	360	eno_rdwrt, /* write */
	361	eno_ioctl, /* ioctl */
	362	(stop_fcn_t )nulldev, / stop */
	363	(reset_fcn_t )nulldev, / reset */
	364	NULL, /* tty's */
	365	eno_select, /* select */
	366	eno_mmap, /* mmap */
	367	eno_strat, /* strategy */
	368	eno_getc, /* getc */
	369	eno_putc, /* putc */
	370	0 /* type */
	371	};
	372
	373	static int gLockstatInited = 0;
	374
	375	void lockstat_init( void );
	376
	377	void lockstat_init( void )
	378	{
	379	if (0 == gLockstatInited)
	380	{
	381	int majdevno = cdevsw_add(LOCKSTAT_MAJOR, &lockstat_cdevsw);
	382
	383	if (majdevno < 0) {
	384	printf("lockstat_init: failed to allocate a major number!\n");
	385	gLockstatInited = 0;
	386	return;
	387	}
	388
b0d623f7	389	lockstat_attach( (dev_info_t *)(uintptr_t)majdevno, DDI_ATTACH );
2d21ac55 A	390	gLockstatInited = 1;
	391	} else
	392	panic("lockstat_init: called twice!\n");
	393	}
	394	#undef LOCKSTAT_MAJOR