1 files changed, 0 insertions, 518 deletions
diff --git a/kernel/marker.c b/kernel/marker.c
deleted file mode 100644
index 5323cfaedbc..00000000000
--- a/kernel/marker.c
+++ /dev/null
@@ -1,518 +0,0 @@
-/*
- * Copyright (C) 2007 Mathieu Desnoyers
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/types.h>
-#include <linux/jhash.h>
-#include <linux/list.h>
-#include <linux/rcupdate.h>
-#include <linux/marker.h>
-#include <linux/err.h>
-
-extern struct marker __start___markers[];
-extern struct marker __stop___markers[];
-
-/*
- * markers_mutex nests inside module_mutex. Markers mutex protects the builtin
- * and module markers, the hash table and deferred_sync.
- */
-static DEFINE_MUTEX(markers_mutex);
-
-/*
- * Marker deferred synchronization.
- * Upon marker probe_unregister, we delay call to synchronize_sched() to
- * accelerate mass unregistration (only when there is no more reference to a
- * given module do we call synchronize_sched()). However, we need to make sure
- * every critical region has ended before we re-arm a marker that has been
- * unregistered and then registered back with a different probe data.
- */
-static int deferred_sync;
-
-/*
- * Marker hash table, containing the active markers.
- * Protected by module_mutex.
- */
-#define MARKER_HASH_BITS 6
-#define MARKER_TABLE_SIZE (1 << MARKER_HASH_BITS)
-
-struct marker_entry {
-	struct hlist_node hlist;
-	char *format;
-	marker_probe_func *probe;
-	void *private;
-	int refcount;	/* Number of times armed. 0 if disarmed. */
-	char name[0];	/* Contains name'\0'format'\0' */
-};
-
-static struct hlist_head marker_table[MARKER_TABLE_SIZE];
-
-/**
- * __mark_empty_function - Empty probe callback
- * @mdata: pointer of type const struct marker
- * @fmt: format string
- * @...: variable argument list
- *
- * Empty callback provided as a probe to the markers. By providing this to a
- * disabled marker, we make sure the  execution flow is always valid even
- * though the function pointer change and the marker enabling are two distinct
- * operations that modifies the execution flow of preemptible code.
- */
-void __mark_empty_function(const struct marker *mdata, void *private,
-	const char *fmt, ...)
-{
-}
-EXPORT_SYMBOL_GPL(__mark_empty_function);
-
-/*
- * Get marker if the marker is present in the marker hash table.
- * Must be called with markers_mutex held.
- * Returns NULL if not present.
- */
-static struct marker_entry *get_marker(const char *name)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	u32 hash = jhash(name, strlen(name), 0);
-
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name))
-			return e;
-	}
-	return NULL;
-}
-
-/*
- * Add the marker to the marker hash table. Must be called with markers_mutex
- * held.
- */
-static int add_marker(const char *name, const char *format,
-	marker_probe_func *probe, void *private)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	size_t name_len = strlen(name) + 1;
-	size_t format_len = 0;
-	u32 hash = jhash(name, name_len-1, 0);
-
-	if (format)
-		format_len = strlen(format) + 1;
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name)) {
-			printk(KERN_NOTICE
-				"Marker %s busy, probe %p already installed\n",
-				name, e->probe);
-			return -EBUSY;	/* Already there */
-		}
-	}
-	/*
-	 * Using kmalloc here to allocate a variable length element. Could
-	 * cause some memory fragmentation if overused.
-	 */
-	e = kmalloc(sizeof(struct marker_entry) + name_len + format_len,
-			GFP_KERNEL);
-	if (!e)
-		return -ENOMEM;
-	memcpy(&e->name[0], name, name_len);
-	if (format) {
-		e->format = &e->name[name_len];
-		memcpy(e->format, format, format_len);
-		trace_mark(core_marker_format, "name %s format %s",
-				e->name, e->format);
-	} else
-		e->format = NULL;
-	e->probe = probe;
-	e->private = private;
-	e->refcount = 0;
-	hlist_add_head(&e->hlist, head);
-	return 0;
-}
-
-/*
- * Remove the marker from the marker hash table. Must be called with mutex_lock
- * held.
- */
-static void *remove_marker(const char *name)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	int found = 0;
-	size_t len = strlen(name) + 1;
-	void *private = NULL;
-	u32 hash = jhash(name, len-1, 0);
-
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name)) {
-			found = 1;
-			break;
-		}
-	}
-	if (found) {
-		private = e->private;
-		hlist_del(&e->hlist);
-		kfree(e);
-	}
-	return private;
-}
-
-/*
- * Set the mark_entry format to the format found in the element.
- */
-static int marker_set_format(struct marker_entry **entry, const char *format)
-{
-	struct marker_entry *e;
-	size_t name_len = strlen((*entry)->name) + 1;
-	size_t format_len = strlen(format) + 1;
-
-	e = kmalloc(sizeof(struct marker_entry) + name_len + format_len,
-			GFP_KERNEL);
-	if (!e)
-		return -ENOMEM;
-	memcpy(&e->name[0], (*entry)->name, name_len);
-	e->format = &e->name[name_len];
-	memcpy(e->format, format, format_len);
-	e->probe = (*entry)->probe;
-	e->private = (*entry)->private;
-	e->refcount = (*entry)->refcount;
-	hlist_add_before(&e->hlist, &(*entry)->hlist);
-	hlist_del(&(*entry)->hlist);
-	kfree(*entry);
-	*entry = e;
-	trace_mark(core_marker_format, "name %s format %s",
-			e->name, e->format);
-	return 0;
-}
-
-/*
- * Sets the probe callback corresponding to one marker.
- */
-static int set_marker(struct marker_entry **entry, struct marker *elem)
-{
-	int ret;
-	WARN_ON(strcmp((*entry)->name, elem->name) != 0);
-
-	if ((*entry)->format) {
-		if (strcmp((*entry)->format, elem->format) != 0) {
-			printk(KERN_NOTICE
-				"Format mismatch for probe %s "
-				"(%s), marker (%s)\n",
-				(*entry)->name,
-				(*entry)->format,
-				elem->format);
-			return -EPERM;
-		}
-	} else {
-		ret = marker_set_format(entry, elem->format);
-		if (ret)
-			return ret;
-	}
-	elem->call = (*entry)->probe;
-	elem->private = (*entry)->private;
-	elem->state = 1;
-	return 0;
-}
-
-/*
- * Disable a marker and its probe callback.
- * Note: only after a synchronize_sched() issued after setting elem->call to the
- * empty function insures that the original callback is not used anymore. This
- * insured by preemption disabling around the call site.
- */
-static void disable_marker(struct marker *elem)
-{
-	elem->state = 0;
-	elem->call = __mark_empty_function;
-	/*
-	 * Leave the private data and id there, because removal is racy and
-	 * should be done only after a synchronize_sched(). These are never used
-	 * until the next initialization anyway.
-	 */
-}
-
-/**
- * marker_update_probe_range - Update a probe range
- * @begin: beginning of the range
- * @end: end of the range
- * @probe_module: module address of the probe being updated
- * @refcount: number of references left to the given probe_module (out)
- *
- * Updates the probe callback corresponding to a range of markers.
- */
-void marker_update_probe_range(struct marker *begin,
-	struct marker *end, struct module *probe_module,
-	int *refcount)
-{
-	struct marker *iter;
-	struct marker_entry *mark_entry;
-
-	mutex_lock(&markers_mutex);
-	for (iter = begin; iter < end; iter++) {
-		mark_entry = get_marker(iter->name);
-		if (mark_entry && mark_entry->refcount) {
-			set_marker(&mark_entry, iter);
-			/*
-			 * ignore error, continue
-			 */
-			if (probe_module)
-				if (probe_module ==
-			__module_text_address((unsigned long)mark_entry->probe))
-					(*refcount)++;
-		} else {
-			disable_marker(iter);
-		}
-	}
-	mutex_unlock(&markers_mutex);
-}
-
-/*
- * Update probes, removing the faulty probes.
- * Issues a synchronize_sched() when no reference to the module passed
- * as parameter is found in the probes so the probe module can be
- * safely unloaded from now on.
- */
-static void marker_update_probes(struct module *probe_module)
-{
-	int refcount = 0;
-
-	/* Core kernel markers */
-	marker_update_probe_range(__start___markers,
-			__stop___markers, probe_module, &refcount);
-	/* Markers in modules. */
-	module_update_markers(probe_module, &refcount);
-	if (probe_module && refcount == 0) {
-		synchronize_sched();
-		deferred_sync = 0;
-	}
-}
-
-/**
- * marker_probe_register -  Connect a probe to a marker
- * @name: marker name
- * @format: format string
- * @probe: probe handler
- * @private: probe private data
- *
- * private data must be a valid allocated memory address, or NULL.
- * Returns 0 if ok, error value on error.
- */
-int marker_probe_register(const char *name, const char *format,
-			marker_probe_func *probe, void *private)
-{
-	struct marker_entry *entry;
-	int ret = 0;
-
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (entry && entry->refcount) {
-		ret = -EBUSY;
-		goto end;
-	}
-	if (deferred_sync) {
-		synchronize_sched();
-		deferred_sync = 0;
-	}
-	ret = add_marker(name, format, probe, private);
-	if (ret)
-		goto end;
-	mutex_unlock(&markers_mutex);
-	marker_update_probes(NULL);
-	return ret;
-end:
-	mutex_unlock(&markers_mutex);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_register);
-
-/**
- * marker_probe_unregister -  Disconnect a probe from a marker
- * @name: marker name
- *
- * Returns the private data given to marker_probe_register, or an ERR_PTR().
- */
-void *marker_probe_unregister(const char *name)
-{
-	struct module *probe_module;
-	struct marker_entry *entry;
-	void *private;
-
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (!entry) {
-		private = ERR_PTR(-ENOENT);
-		goto end;
-	}
-	entry->refcount = 0;
-	/* In what module is the probe handler ? */
-	probe_module = __module_text_address((unsigned long)entry->probe);
-	private = remove_marker(name);
-	deferred_sync = 1;
-	mutex_unlock(&markers_mutex);
-	marker_update_probes(probe_module);
-	return private;
-end:
-	mutex_unlock(&markers_mutex);
-	return private;
-}
-EXPORT_SYMBOL_GPL(marker_probe_unregister);
-
-/**
- * marker_probe_unregister_private_data -  Disconnect a probe from a marker
- * @private: probe private data
- *
- * Unregister a marker by providing the registered private data.
- * Returns the private data given to marker_probe_register, or an ERR_PTR().
- */
-void *marker_probe_unregister_private_data(void *private)
-{
-	struct module *probe_module;
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *entry;
-	int found = 0;
-	unsigned int i;
-
-	mutex_lock(&markers_mutex);
-	for (i = 0; i < MARKER_TABLE_SIZE; i++) {
-		head = &marker_table[i];
-		hlist_for_each_entry(entry, node, head, hlist) {
-			if (entry->private == private) {
-				found = 1;
-				goto iter_end;
-			}
-		}
-	}
-iter_end:
-	if (!found) {
-		private = ERR_PTR(-ENOENT);
-		goto end;
-	}
-	entry->refcount = 0;
-	/* In what module is the probe handler ? */
-	probe_module = __module_text_address((unsigned long)entry->probe);
-	private = remove_marker(entry->name);
-	deferred_sync = 1;
-	mutex_unlock(&markers_mutex);
-	marker_update_probes(probe_module);
-	return private;
-end:
-	mutex_unlock(&markers_mutex);
-	return private;
-}
-EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data);
-
-/**
- * marker_arm - Arm a marker
- * @name: marker name
- *
- * Activate a marker. It keeps a reference count of the number of
- * arming/disarming done.
- * Returns 0 if ok, error value on error.
- */
-int marker_arm(const char *name)
-{
-	struct marker_entry *entry;
-	int ret = 0;
-
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (!entry) {
-		ret = -ENOENT;
-		goto end;
-	}
-	/*
-	 * Only need to update probes when refcount passes from 0 to 1.
-	 */
-	if (entry->refcount++)
-		goto end;
-end:
-	mutex_unlock(&markers_mutex);
-	marker_update_probes(NULL);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(marker_arm);
-
-/**
- * marker_disarm - Disarm a marker
- * @name: marker name
- *
- * Disarm a marker. It keeps a reference count of the number of arming/disarming
- * done.
- * Returns 0 if ok, error value on error.
- */
-int marker_disarm(const char *name)
-{
-	struct marker_entry *entry;
-	int ret = 0;
-
-	mutex_lock(&markers_mutex);
-	entry = get_marker(name);
-	if (!entry) {
-		ret = -ENOENT;
-		goto end;
-	}
-	/*
-	 * Only permit decrement refcount if higher than 0.
-	 * Do probe update only on 1 -> 0 transition.
-	 */
-	if (entry->refcount) {
-		if (--entry->refcount)
-			goto end;
-	} else {
-		ret = -EPERM;
-		goto end;
-	}
-end:
-	mutex_unlock(&markers_mutex);
-	marker_update_probes(NULL);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(marker_disarm);
-
-/**
- * marker_get_private_data - Get a marker's probe private data
- * @name: marker name
- *
- * Returns the private data pointer, or an ERR_PTR.
- * The private data pointer should _only_ be dereferenced if the caller is the
- * owner of the data, or its content could vanish. This is mostly used to
- * confirm that a caller is the owner of a registered probe.
- */
-void *marker_get_private_data(const char *name)
-{
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct marker_entry *e;
-	size_t name_len = strlen(name) + 1;
-	u32 hash = jhash(name, name_len-1, 0);
-	int found = 0;
-
-	head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
-	hlist_for_each_entry(e, node, head, hlist) {
-		if (!strcmp(name, e->name)) {
-			found = 1;
-			return e->private;
-		}
-	}
-	return ERR_PTR(-ENOENT);
-}
-EXPORT_SYMBOL_GPL(marker_get_private_data);