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bsd/dev/dtrace/lockprof.c xnu-12377.121.6 /dev/null
--- xnu/xnu-12377.121.6/bsd/dev/dtrace/lockprof.c
+++ /dev/null
@@ -1,424 +0,0 @@
-/*
- * Copyright (c) 2019 Apple Inc. All rights reserved.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- *
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
- */
-#include <sys/ioctl.h>
-
-#include <sys/stat.h>
-#include <miscfs/devfs/devfs.h>
-#include <sys/conf.h>
-#include <sys/systm.h>
-#include <sys/dtrace.h>
-#include <sys/dtrace_impl.h>
-#include <kern/lock_group.h>
-#include <kern/lock_stat.h>
-
-#if LOCK_STATS
-
-#define LP_NODE "lockprof"
-
-#define LOCKPROF_AFRAMES 3
-#define LOCKPROF_LEN 64
-
-static dtrace_provider_id_t lockprof_id;
-
-#define LOCKPROF_MAX 10000 /* maximum number of lockprof probes */
-static uint32_t lockprof_count; /* current number of lockprof probes */
-
-enum probe_flags {
-	/*
-	 * Counts time spent spinning/blocking
-	 */
-	TIME_EVENT = 0x01,
-	/*
-	 * Requires LCK_GRP_ATTR_STAT to be set on the lock
-	 * group, either via lck_grp_attr_setsta on the lock group,
-	 * or globally via the lcks=3 boot-arg
-	 */
-	STAT_NEEDED = 0x02
-};
-
-static const struct {
-	const char *prefix;
-	int flags;
-	size_t count_offset;
-	size_t stat_offset;
-} probes[] = {
-	{"spin-held-", 0, offsetof(lck_grp_t, lck_grp_spincnt), offsetof(lck_grp_stats_t, lgss_spin_held)},
-	{"spin-miss-", 0, offsetof(lck_grp_t, lck_grp_spincnt), offsetof(lck_grp_stats_t, lgss_spin_miss)},
-	{"spin-spin-", TIME_EVENT, offsetof(lck_grp_t, lck_grp_spincnt), offsetof(lck_grp_stats_t, lgss_spin_spin)},
-	{"ticket-held-", 0, offsetof(lck_grp_t, lck_grp_ticketcnt), offsetof(lck_grp_stats_t, lgss_ticket_held)},
-	{"ticket-miss-", 0, offsetof(lck_grp_t, lck_grp_ticketcnt), offsetof(lck_grp_stats_t, lgss_ticket_miss)},
-	{"ticket-spin-", TIME_EVENT, offsetof(lck_grp_t, lck_grp_ticketcnt), offsetof(lck_grp_stats_t, lgss_ticket_spin)},
-	{"adaptive-held-", STAT_NEEDED, offsetof(lck_grp_t, lck_grp_mtxcnt), offsetof(lck_grp_stats_t, lgss_mtx_held)},
-	{"adaptive-miss-", STAT_NEEDED, offsetof(lck_grp_t, lck_grp_mtxcnt), offsetof(lck_grp_stats_t, lgss_mtx_miss)},
-	{"adaptive-wait-", STAT_NEEDED, offsetof(lck_grp_t, lck_grp_mtxcnt), offsetof(lck_grp_stats_t, lgss_mtx_wait)},
-	{"adaptive-direct-wait-", STAT_NEEDED, offsetof(lck_grp_t, lck_grp_mtxcnt), offsetof(lck_grp_stats_t, lgss_mtx_direct_wait)},
-	{NULL, false, 0, 0}
-};
-
-/*
- * Default defined probes for counting events
- */
-const static int hold_defaults[] = {
-	10000 /* 10000 events */
-};
-
-/*
- * Default defined probes for time events
- */
-const static struct {
-	unsigned int time;
-	const char *suffix;
-	uint64_t mult;
-} cont_defaults[] = {
-	{100, "ms", NANOSEC / MILLISEC} /* 100 ms */
-};
-
-typedef struct lockprof_probe {
-	int lockprof_kind;
-	dtrace_id_t lockprof_id;
-	uint64_t lockprof_limit;
-	lck_grp_t *lockprof_grp;
-} lockprof_probe_t;
-
-static int
-lockprof_lock_count(lck_grp_t *grp, int kind)
-{
-	return *(int*)((uintptr_t)(grp) + probes[kind].count_offset);
-}
-
-static void
-probe_create(int kind, const char *suffix, const char *grp_name, uint64_t count, uint64_t mult)
-{
-	uint64_t limit = count * mult;
-
-	if (probes[kind].flags & TIME_EVENT) {
-		nanoseconds_to_absolutetime(limit, &limit);
-	}
-
-	lck_grp_foreach(^bool (lck_grp_t *grp) {
-		char name[LOCKPROF_LEN];
-
-		if (!grp_name || grp_name[0] == '\0' || strcmp(grp_name, grp->lck_grp_name) == 0) {
-		        snprintf(name, sizeof(name), "%s%llu%s", probes[kind].prefix, count, suffix ?: "");
-
-		        if (dtrace_probe_lookup(lockprof_id, grp->lck_grp_name, NULL, name) != 0) {
-		                return true;
-			}
-		        if (lockprof_lock_count(grp, kind) == 0) {
-		                return true;
-			}
-		        if ((probes[kind].flags & STAT_NEEDED) && !lck_grp_has_stats(grp)) {
-		                return true;
-			}
-		        if (lockprof_count >= LOCKPROF_MAX) {
-		                return false;
-			}
-
-		        lockprof_probe_t *probe = kmem_zalloc(sizeof(lockprof_probe_t), KM_SLEEP);
-		        probe->lockprof_kind = kind;
-		        probe->lockprof_limit = limit;
-		        probe->lockprof_grp = grp;
-
-		        lck_grp_reference(grp, NULL);
-
-		        probe->lockprof_id = dtrace_probe_create(lockprof_id, grp->lck_grp_name, NULL, name,
-		        LOCKPROF_AFRAMES, probe);
-
-		        lockprof_count++;
-		}
-
-		return true;
-	});
-}
-
-static void
-lockprof_provide(void *arg, const dtrace_probedesc_t *desc)
-{
-#pragma unused(arg)
-	size_t event_id, i, j, len;
-
-	if (desc == NULL) {
-		for (i = 0; i < sizeof(hold_defaults) / sizeof(hold_defaults[0]); i++) {
-			for (j = 0; probes[j].prefix != NULL; j++) {
-				if (!(probes[j].flags & TIME_EVENT)) {
-					probe_create(j, NULL, NULL, hold_defaults[i], 1);
-				}
-			}
-		}
-		for (i = 0; i < sizeof(cont_defaults) / sizeof(cont_defaults[0]); i++) {
-			for (j = 0; probes[j].prefix != NULL; j++) {
-				if (probes[j].flags & TIME_EVENT) {
-					probe_create(j, cont_defaults[i].suffix, NULL, cont_defaults[i].time, cont_defaults[i].mult);
-				}
-			}
-		}
-		return;
-	}
-
-	const char *name, *suffix = NULL;
-	hrtime_t val = 0, mult = 1;
-
-	const struct {
-		const char *name;
-		hrtime_t mult;
-	} suffixes[] = {
-		{ "us", NANOSEC / MICROSEC },
-		{ "usec", NANOSEC / MICROSEC },
-		{ "ms", NANOSEC / MILLISEC },
-		{ "msec", NANOSEC / MILLISEC },
-		{ "s", NANOSEC / SEC },
-		{ "sec", NANOSEC / SEC },
-		{ NULL, 0 }
-	};
-
-	name = desc->dtpd_name;
-
-	for (event_id = 0; probes[event_id].prefix != NULL; event_id++) {
-		len = strlen(probes[event_id].prefix);
-
-		if (strncmp(name, probes[event_id].prefix, len) != 0) {
-			continue;
-		}
-		break;
-	}
-
-	if (probes[event_id].prefix == NULL) {
-		return;
-	}
-
-
-	/*
-	 * We need to start before any time suffix.
-	 */
-	for (i = strlen(name); i >= len; i--) {
-		if (name[i] >= '0' && name[i] <= '9') {
-			break;
-		}
-		suffix = &name[i];
-	}
-
-	/*
-	 * Now determine the numerical value present in the probe name.
-	 */
-	for (uint64_t m = 1; i >= len; i--) {
-		if (name[i] < '0' || name[i] > '9') {
-			return;
-		}
-
-		val += (name[i] - '0') * m;
-		m *= (hrtime_t)10;
-	}
-
-	if (val == 0) {
-		return;
-	}
-
-	if (probes[event_id].flags & TIME_EVENT) {
-		for (i = 0, mult = 0; suffixes[i].name != NULL; i++) {
-			if (suffix && (strncasecmp(suffixes[i].name, suffix, strlen(suffixes[i].name) + 1) == 0)) {
-				mult = suffixes[i].mult;
-				break;
-			}
-		}
-		if (suffixes[i].name == NULL) {
-			return;
-		}
-	} else if (suffix && (*suffix != '\0')) {
-		return;
-	}
-
-	probe_create(event_id, suffix, desc->dtpd_mod, val, mult);
-}
-
-
-static lck_grp_stat_t*
-lockprof_stat(lck_grp_t *grp, int kind)
-{
-	return (lck_grp_stat_t*)((uintptr_t)&grp->lck_grp_stats + probes[kind].stat_offset);
-}
-
-static int
-lockprof_enable(void *arg, dtrace_id_t id, void *parg)
-{
-#pragma unused(arg, id, parg)
-	lockprof_probe_t *probe = (lockprof_probe_t*)parg;
-	lck_grp_t *grp = probe->lockprof_grp;
-	lck_grp_stat_t *stat;
-
-	if (grp == NULL) {
-		return -1;
-	}
-
-	if ((stat = lockprof_stat(grp, probe->lockprof_kind)) == NULL) {
-		return -1;
-	}
-
-	/*
-	 * lockprof_enable/disable are called with
-	 * dtrace_lock held
-	 */
-	if (stat->lgs_limit != 0) {
-		return -1;
-	}
-
-	stat->lgs_limit = probe->lockprof_limit;
-	stat->lgs_probeid = probe->lockprof_id;
-	lck_grp_stat_enable(stat);
-	lck_grp_enable_feature(LCK_DEBUG_LOCKPROF);
-
-	return 0;
-}
-
-static void
-lockprof_disable(void *arg, dtrace_id_t id, void *parg)
-{
-#pragma unused(arg, id)
-	lockprof_probe_t *probe = (lockprof_probe_t*)parg;
-	lck_grp_t *grp = probe->lockprof_grp;
-	lck_grp_stat_t *stat;
-
-	if (grp == NULL) {
-		return;
-	}
-
-	if ((stat = lockprof_stat(grp, probe->lockprof_kind)) == NULL) {
-		return;
-	}
-
-	if (stat->lgs_limit == 0 || !lck_grp_stat_enabled(stat)) {
-		return;
-	}
-
-	stat->lgs_limit = 0;
-	stat->lgs_probeid = 0;
-	lck_grp_stat_disable(stat);
-	lck_grp_disable_feature(LCK_DEBUG_LOCKPROF);
-}
-
-static void
-lockprof_destroy(void *arg, dtrace_id_t id, void *parg)
-{
-#pragma unused(arg, id)
-	lockprof_probe_t *probe = (lockprof_probe_t*)parg;
-	lck_grp_deallocate(probe->lockprof_grp, NULL);
-	kmem_free(probe, sizeof(lockprof_probe_t));
-	lockprof_count--;
-}
-
-static void
-lockprof_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc)
-{
-#pragma unused(arg, id, parg)
-	const char *argdesc = NULL;
-	switch (desc->dtargd_ndx) {
-	case 0:
-		argdesc = "lck_grp_t*";
-		break;
-	case 1:
-		argdesc = "uint64_t";
-		break;
-	}
-
-	if (argdesc) {
-		strlcpy(desc->dtargd_native, argdesc, DTRACE_ARGTYPELEN);
-	} else {
-		desc->dtargd_ndx = DTRACE_ARGNONE;
-	}
-}
-static dtrace_pattr_t lockprof_attr = {
-	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
-	{ DTRACE_STABILITY_UNSTABLE, DTRACE_STABILITY_UNSTABLE, 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 lockprof_pops = {
-	.dtps_provide =         lockprof_provide,
-	.dtps_provide_module =  NULL,
-	.dtps_enable =          lockprof_enable,
-	.dtps_disable =         lockprof_disable,
-	.dtps_suspend =         NULL,
-	.dtps_resume =          NULL,
-	.dtps_getargdesc =      lockprof_getargdesc,
-	.dtps_getargval =       NULL,
-	.dtps_usermode =        NULL,
-	.dtps_destroy =         lockprof_destroy
-};
-
-static int
-_lockprof_open(dev_t dev, int flags, int devtype, struct proc *p)
-{
-#pragma unused(dev,flags,devtype,p)
-	return 0;
-}
-
-static const struct cdevsw lockprof_cdevsw =
-{
-	.d_open = _lockprof_open,
-	.d_close = eno_opcl,
-	.d_read = eno_rdwrt,
-	.d_write = eno_rdwrt,
-	.d_ioctl = eno_ioctl,
-	.d_stop = eno_stop,
-	.d_reset = eno_reset,
-	.d_select = eno_select,
-	.d_mmap = eno_mmap,
-	.d_strategy = eno_strat,
-	.d_reserved_1 = eno_getc,
-	.d_reserved_2 = eno_putc,
-};
-
-
-#endif /* LOCK_STATS */
-void lockprof_init(void);
-void
-lockprof_init(void)
-{
-#if LOCK_STATS
-	int majorno = cdevsw_add(-1, &lockprof_cdevsw);
-
-	if (majorno < 0) {
-		panic("dtrace: failed to allocate a major number");
-		return;
-	}
-
-	if (dtrace_register(LP_NODE, &lockprof_attr, DTRACE_PRIV_KERNEL,
-	    NULL, &lockprof_pops, NULL, &lockprof_id) != 0) {
-		panic("dtrace: failed to register lockprof provider");
-	}
-
-	dev_t dev = makedev(majorno, 0);
-
-	if (devfs_make_node( dev, DEVFS_CHAR, UID_ROOT, GID_WHEEL, 0666,
-	    LP_NODE ) == NULL) {
-		panic("dtrace: devfs_make_node failed for lockprof");
-	}
-
-#endif /* LOCK_STATS */
-}