X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/4d15aeb193b2c68f1d38666c317f8d3734f5f083..5ba3f43ea354af8ad55bea84372a2bc834d8757c:/bsd/dev/monotonic.c

diff --git a/bsd/dev/monotonic.c b/bsd/dev/monotonic.c
new file mode 100644
index 000000000..91ef1f2bd
--- /dev/null
+++ b/bsd/dev/monotonic.c
@@ -0,0 +1,459 @@
+/*
+ * Copyright (c) 2017 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 <kern/monotonic.h>
+#include <machine/machine_routines.h>
+#include <machine/monotonic.h>
+#include <pexpert/pexpert.h>
+#include <sys/param.h> /* NULL */
+#include <sys/stat.h> /* dev_t */
+#include <miscfs/devfs/devfs.h> /* must come after sys/stat.h */
+#include <sys/conf.h> /* must come after sys/stat.h */
+#include <sys/sysctl.h>
+#include <sys/sysproto.h>
+#include <sys/systm.h>
+#include <sys/types.h>
+#include <sys/monotonic.h>
+
+static int mt_dev_open(dev_t dev, int flags, int devtype, struct proc *p);
+static int mt_dev_close(dev_t dev, int flags, int devtype, struct proc *p);
+static int mt_dev_ioctl(dev_t dev, unsigned long cmd, char *uptr, int fflag,
+		struct proc *p);
+
+static struct cdevsw mt_cdevsw = {
+	.d_open = mt_dev_open,
+	.d_close = mt_dev_close,
+	.d_read = eno_rdwrt,
+	.d_write = eno_rdwrt,
+	.d_ioctl = mt_dev_ioctl,
+	.d_stop = eno_stop,
+	.d_reset = eno_reset,
+	.d_ttys = NULL,
+	.d_select = eno_select,
+	.d_mmap = eno_mmap,
+	.d_strategy = eno_strat,
+	.d_type = 0
+};
+
+/*
+ * Written at initialization, read-only thereafter.
+ */
+lck_grp_t *mt_lock_grp = NULL;
+
+static int mt_dev_major;
+decl_lck_mtx_data(static, mt_dev_mtxs[MT_NDEVS]);
+static bool mt_dev_owned[MT_NDEVS];
+
+static void
+mt_dev_lock(dev_t dev)
+{
+	lck_mtx_lock(&mt_dev_mtxs[minor(dev)]);
+}
+
+static void
+mt_dev_unlock(dev_t dev)
+{
+	lck_mtx_unlock(&mt_dev_mtxs[minor(dev)]);
+}
+
+static void
+mt_dev_assert_lock_held(__assert_only dev_t dev)
+{
+	LCK_MTX_ASSERT(&mt_dev_mtxs[minor(dev)], LCK_MTX_ASSERT_OWNED);
+}
+
+int
+mt_dev_init(void)
+{
+	lck_grp_attr_t *lock_grp_attr = NULL;
+	int devices = 0;
+
+	lock_grp_attr = lck_grp_attr_alloc_init();
+	mt_lock_grp = lck_grp_alloc_init("monotonic", lock_grp_attr);
+	lck_grp_attr_free(lock_grp_attr);
+
+	mt_dev_major = cdevsw_add(-1 /* allocate a major number */, &mt_cdevsw);
+	if (mt_dev_major < 0) {
+		panic("monotonic: cdevsw_add failed: %d", mt_dev_major);
+		__builtin_trap();
+	}
+
+	for (int i = 0; i < MT_NDEVS; i++) {
+		dev_t dev;
+		void *dn;
+		int error;
+
+		error = monotonic_devs[i].mtd_init();
+		if (error) {
+			continue;
+		}
+
+		dev = makedev(mt_dev_major, i);
+		dn = devfs_make_node(dev,
+				DEVFS_CHAR, UID_ROOT, GID_WINDOWSERVER, 0666,
+				monotonic_devs[i].mtd_name);
+		if (dn == NULL) {
+			panic("monotonic: devfs_make_node failed for '%s'",
+					monotonic_devs[i].mtd_name);
+			__builtin_trap();
+		}
+
+		lck_mtx_init(&mt_dev_mtxs[i], mt_lock_grp, LCK_ATTR_NULL);
+
+		devices++;
+	}
+
+	return 0;
+}
+
+static int
+mt_dev_open(dev_t dev, __unused int flags, __unused int devtype,
+		__unused struct proc *p)
+{
+	int error = 0;
+
+	mt_dev_lock(dev);
+
+	if (mt_dev_owned[minor(dev)]) {
+		error = EBUSY;
+		goto out;
+	}
+
+	mt_dev_owned[minor(dev)] = true;
+
+out:
+	mt_dev_unlock(dev);
+	return error;
+}
+
+static int
+mt_dev_close(dev_t dev, __unused int flags, __unused int devtype,
+		__unused struct proc *p)
+{
+	mt_dev_lock(dev);
+
+	assert(mt_dev_owned[minor(dev)]);
+	mt_dev_owned[minor(dev)] = false;
+
+	monotonic_devs[minor(dev)].mtd_reset();
+
+	mt_dev_unlock(dev);
+
+	return 0;
+}
+
+static int
+mt_ctl_add(dev_t dev, user_addr_t uptr, __unused int flags,
+		__unused struct proc *p)
+{
+	int error;
+	uint32_t ctr;
+	union monotonic_ctl_add ctl;
+
+	mt_dev_assert_lock_held(dev);
+
+	error = copyin(uptr, &ctl, sizeof(ctl.in));
+	if (error) {
+		return error;
+	}
+
+	error = monotonic_devs[minor(dev)].mtd_add(&ctl.in.config, &ctr);
+	if (error) {
+		return error;
+	}
+
+	ctl.out.ctr = ctr;
+
+	error = copyout(&ctl, uptr, sizeof(ctl.out));
+	if (error) {
+		return error;
+	}
+
+	return 0;
+}
+
+static int
+mt_ctl_counts(dev_t dev, user_addr_t uptr, __unused int flags,
+		__unused struct proc *p)
+{
+	int error;
+	uint64_t ctrs;
+	union monotonic_ctl_counts ctl;
+
+	mt_dev_assert_lock_held(dev);
+
+	error = copyin(uptr, &ctl, sizeof(ctl.in));
+	if (error) {
+		return error;
+	}
+
+	if (ctl.in.ctr_mask == 0) {
+		return EINVAL;
+	}
+	ctrs = __builtin_popcountll(ctl.in.ctr_mask);
+
+	{
+		uint64_t counts[ctrs];
+		error = monotonic_devs[minor(dev)].mtd_read(ctl.in.ctr_mask, counts);
+		if (error) {
+			return error;
+		}
+
+		error = copyout(&counts, uptr, sizeof(counts));
+		if (error) {
+			return error;
+		}
+	}
+
+	return 0;
+}
+
+static int
+mt_ctl_enable(dev_t dev, user_addr_t uptr)
+{
+	int error;
+	union monotonic_ctl_enable ctl;
+
+	mt_dev_assert_lock_held(dev);
+
+	error = copyin(uptr, &ctl, sizeof(ctl));
+	if (error) {
+		return error;
+	}
+
+	monotonic_devs[minor(dev)].mtd_enable(ctl.in.enable);
+
+	return 0;
+}
+
+static int
+mt_ctl_reset(dev_t dev)
+{
+	mt_dev_assert_lock_held(dev);
+	monotonic_devs[minor(dev)].mtd_reset();
+	return 0;
+}
+
+static int
+mt_dev_ioctl(dev_t dev, unsigned long cmd, char *arg, int flags,
+		struct proc *p)
+{
+	int error;
+	user_addr_t uptr = *(user_addr_t *)(void *)arg;
+
+	mt_dev_lock(dev);
+
+	switch (cmd) {
+	case MT_IOC_RESET:
+		error = mt_ctl_reset(dev);
+		break;
+
+	case MT_IOC_ADD:
+		error = mt_ctl_add(dev, uptr, flags, p);
+		break;
+
+	case MT_IOC_ENABLE:
+		error = mt_ctl_enable(dev, uptr);
+		break;
+
+	case MT_IOC_COUNTS:
+		error = mt_ctl_counts(dev, uptr, flags, p);
+		break;
+
+	default:
+		error = ENODEV;
+		break;
+	}
+
+	mt_dev_unlock(dev);
+
+	return error;
+}
+
+int thread_selfcounts(__unused struct proc *p,
+		struct thread_selfcounts_args *uap, __unused int *ret_out)
+{
+	switch (uap->type) {
+	case 1: {
+		uint64_t counts[2] = {};
+		uint64_t thread_counts[MT_CORE_NFIXED];
+
+		mt_cur_thread_fixed_counts(thread_counts);
+
+#ifdef MT_CORE_INSTRS
+		counts[0] = thread_counts[MT_CORE_INSTRS];
+#endif /* defined(MT_CORE_INSTRS) */
+		counts[1] = thread_counts[MT_CORE_CYCLES];
+
+		return copyout(counts, uap->buf, MIN(sizeof(counts), uap->nbytes));
+	}
+	default:
+		return EINVAL;
+	}
+}
+
+enum mt_sysctl {
+	MT_SUPPORTED,
+	MT_PMIS,
+	MT_RETROGRADE,
+	MT_TASK_THREAD,
+	MT_DEBUG,
+	MT_KDBG_TEST,
+	MT_FIX_CPU_PERF,
+	MT_FIX_THREAD_PERF,
+	MT_FIX_TASK_PERF,
+};
+
+static int
+mt_sysctl SYSCTL_HANDLER_ARGS
+{
+#pragma unused(oidp, arg2)
+	uint64_t start[MT_CORE_NFIXED], end[MT_CORE_NFIXED];
+	uint64_t counts[2] = {};
+
+	switch ((enum mt_sysctl)arg1) {
+	case MT_SUPPORTED:
+		return sysctl_io_number(req, mt_core_supported, sizeof(mt_core_supported), NULL, NULL);
+	case MT_PMIS:
+		return sysctl_io_number(req, mt_pmis, sizeof(mt_pmis), NULL, NULL);
+	case MT_RETROGRADE:
+		return sysctl_io_number(req, mt_retrograde, sizeof(mt_retrograde), NULL, NULL);
+	case MT_TASK_THREAD:
+		return sysctl_io_number(req, mt_core_supported, sizeof(mt_core_supported), NULL, NULL);
+	case MT_DEBUG: {
+		int value = mt_debug;
+
+		int r = sysctl_io_number(req, value, sizeof(value), &value, NULL);
+		if (r) {
+			return r;
+		}
+		mt_debug = value;
+
+		return 0;
+	}
+	case MT_KDBG_TEST: {
+		if (req->newptr == USER_ADDR_NULL) {
+			return EINVAL;
+		}
+
+		int intrs_en = ml_set_interrupts_enabled(FALSE);
+		MT_KDBG_TMPCPU_START(0x3fff);
+		MT_KDBG_TMPCPU_END(0x3fff);
+
+		MT_KDBG_TMPTH_START(0x3fff);
+		MT_KDBG_TMPTH_END(0x3fff);
+		ml_set_interrupts_enabled(intrs_en);
+
+		return 0;
+	}
+	case MT_FIX_CPU_PERF: {
+		int intrs_en = ml_set_interrupts_enabled(FALSE);
+		mt_fixed_counts(start);
+		mt_fixed_counts(end);
+		ml_set_interrupts_enabled(intrs_en);
+
+		goto copyout_counts;
+	}
+	case MT_FIX_THREAD_PERF: {
+		int intrs_en = ml_set_interrupts_enabled(FALSE);
+		mt_cur_thread_fixed_counts(start);
+		mt_cur_thread_fixed_counts(end);
+		ml_set_interrupts_enabled(intrs_en);
+
+		goto copyout_counts;
+	}
+	case MT_FIX_TASK_PERF: {
+		int intrs_en = ml_set_interrupts_enabled(FALSE);
+		mt_cur_task_fixed_counts(start);
+		mt_cur_task_fixed_counts(end);
+		ml_set_interrupts_enabled(intrs_en);
+
+		goto copyout_counts;
+	}
+	default:
+		return ENOENT;
+	}
+
+copyout_counts:
+
+#ifdef MT_CORE_INSTRS
+	counts[0] = end[MT_CORE_INSTRS] - start[MT_CORE_INSTRS];
+#endif /* defined(MT_CORE_INSTRS) */
+	counts[1] = end[MT_CORE_CYCLES] - start[MT_CORE_CYCLES];
+
+	return copyout(counts, req->oldptr, MIN(req->oldlen, sizeof(counts)));
+}
+
+SYSCTL_DECL(_kern_monotonic);
+SYSCTL_NODE(_kern, OID_AUTO, monotonic, CTLFLAG_RW | CTLFLAG_LOCKED, 0,
+		"monotonic");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, supported,
+		CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MASKED | CTLFLAG_LOCKED,
+		(void *)MT_SUPPORTED, sizeof(int), mt_sysctl, "I",
+		"whether monotonic is supported");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, debug,
+		CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MASKED,
+		(void *)MT_DEBUG, sizeof(int), mt_sysctl, "I",
+		"whether monotonic is printing debug messages");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, pmis,
+		CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MASKED | CTLFLAG_LOCKED,
+		(void *)MT_PMIS, sizeof(uint64_t), mt_sysctl, "Q",
+		"how many PMIs have been seen");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, retrograde_updates,
+		CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MASKED | CTLFLAG_LOCKED,
+		(void *)MT_RETROGRADE, sizeof(uint64_t), mt_sysctl, "Q",
+		"how many times a counter appeared to go backwards");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, task_thread_counting,
+		CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MASKED,
+		(void *)MT_TASK_THREAD, sizeof(int), mt_sysctl, "I",
+		"task and thread counting enabled");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, kdebug_test,
+		CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MASKED | CTLFLAG_LOCKED,
+		(void *)MT_KDBG_TEST, sizeof(int), mt_sysctl, "O",
+		"test that kdebug integration works");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, fixed_cpu_perf,
+		CTLFLAG_RW | CTLFLAG_MASKED | CTLFLAG_LOCKED,
+		(void *)MT_FIX_CPU_PERF, sizeof(uint64_t) * 2, mt_sysctl, "O",
+		"overhead of accessing the current CPU's counters");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, fixed_thread_perf,
+		CTLFLAG_RW | CTLFLAG_MASKED | CTLFLAG_LOCKED,
+		(void *)MT_FIX_THREAD_PERF, sizeof(uint64_t) * 2, mt_sysctl, "O",
+		"overhead of accessing the current thread's counters");
+
+SYSCTL_PROC(_kern_monotonic, OID_AUTO, fixed_task_perf,
+		CTLFLAG_RW | CTLFLAG_MASKED | CTLFLAG_LOCKED,
+		(void *)MT_FIX_TASK_PERF, sizeof(uint64_t) * 2, mt_sysctl, "O",
+		"overhead of accessing the current task's counters");