1 files changed, 63 insertions, 73 deletions

diff --git a/kernel/gcov/base.c b/kernel/gcov/base.c
index 9b22d03cc581..073a3738c5e6 100644
--- a/kernel/gcov/base.c
+++ b/kernel/gcov/base.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  This code maintains a list of active profiling data structures.
  *
@@ -18,119 +19,108 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/sched.h>
 #include "gcov.h"
 
-static struct gcov_info *gcov_info_head;
-static int gcov_events_enabled;
-static DEFINE_MUTEX(gcov_lock);
+int gcov_events_enabled;
+DEFINE_MUTEX(gcov_lock);
 
-/*
- * __gcov_init is called by gcc-generated constructor code for each object
- * file compiled with -fprofile-arcs.
+/**
+ * gcov_enable_events - enable event reporting through gcov_event()
+ *
+ * Turn on reporting of profiling data load/unload-events through the
+ * gcov_event() callback. Also replay all previous events once. This function
+ * is needed because some events are potentially generated too early for the
+ * callback implementation to handle them initially.
  */
-void __gcov_init(struct gcov_info *info)
+void gcov_enable_events(void)
 {
-	static unsigned int gcov_version;
+	struct gcov_info *info = NULL;
 
 	mutex_lock(&gcov_lock);
-	if (gcov_version == 0) {
-		gcov_version = info->version;
-		/*
-		 * Printing gcc's version magic may prove useful for debugging
-		 * incompatibility reports.
-		 */
-		pr_info("version magic: 0x%x\n", gcov_version);
-	}
-	/*
-	 * Add new profiling data structure to list and inform event
-	 * listener.
-	 */
-	info->next = gcov_info_head;
-	gcov_info_head = info;
-	if (gcov_events_enabled)
+	gcov_events_enabled = 1;
+
+	/* Perform event callback for previously registered entries. */
+	while ((info = gcov_info_next(info))) {
 		gcov_event(GCOV_ADD, info);
+		cond_resched();
+	}
+
 	mutex_unlock(&gcov_lock);
 }
-EXPORT_SYMBOL(__gcov_init);
 
-/*
- * These functions may be referenced by gcc-generated profiling code but serve
- * no function for kernel profiling.
+/**
+ * store_gcov_u32 - store 32 bit number in gcov format to buffer
+ * @buffer: target buffer or NULL
+ * @off: offset into the buffer
+ * @v: value to be stored
+ *
+ * Number format defined by gcc: numbers are recorded in the 32 bit
+ * unsigned binary form of the endianness of the machine generating the
+ * file. Returns the number of bytes stored. If @buffer is %NULL, doesn't
+ * store anything.
  */
-void __gcov_flush(void)
+size_t store_gcov_u32(void *buffer, size_t off, u32 v)
 {
-	/* Unused. */
-}
-EXPORT_SYMBOL(__gcov_flush);
+	u32 *data;
 
-void __gcov_merge_add(gcov_type *counters, unsigned int n_counters)
-{
-	/* Unused. */
-}
-EXPORT_SYMBOL(__gcov_merge_add);
-
-void __gcov_merge_single(gcov_type *counters, unsigned int n_counters)
-{
-	/* Unused. */
-}
-EXPORT_SYMBOL(__gcov_merge_single);
+	if (buffer) {
+		data = buffer + off;
+		*data = v;
+	}
 
-void __gcov_merge_delta(gcov_type *counters, unsigned int n_counters)
-{
-	/* Unused. */
+	return sizeof(*data);
 }
-EXPORT_SYMBOL(__gcov_merge_delta);
 
 /**
- * gcov_enable_events - enable event reporting through gcov_event()
+ * store_gcov_u64 - store 64 bit number in gcov format to buffer
+ * @buffer: target buffer or NULL
+ * @off: offset into the buffer
+ * @v: value to be stored
  *
- * Turn on reporting of profiling data load/unload-events through the
- * gcov_event() callback. Also replay all previous events once. This function
- * is needed because some events are potentially generated too early for the
- * callback implementation to handle them initially.
+ * Number format defined by gcc: numbers are recorded in the 32 bit
+ * unsigned binary form of the endianness of the machine generating the
+ * file. 64 bit numbers are stored as two 32 bit numbers, the low part
+ * first. Returns the number of bytes stored. If @buffer is %NULL, doesn't store
+ * anything.
  */
-void gcov_enable_events(void)
+size_t store_gcov_u64(void *buffer, size_t off, u64 v)
 {
-	struct gcov_info *info;
+	u32 *data;
 
-	mutex_lock(&gcov_lock);
-	gcov_events_enabled = 1;
-	/* Perform event callback for previously registered entries. */
-	for (info = gcov_info_head; info; info = info->next)
-		gcov_event(GCOV_ADD, info);
-	mutex_unlock(&gcov_lock);
-}
+	if (buffer) {
+		data = buffer + off;
 
-#ifdef CONFIG_MODULES
-static inline int within(void *addr, void *start, unsigned long size)
-{
-	return ((addr >= start) && (addr < start + size));
+		data[0] = (v & 0xffffffffUL);
+		data[1] = (v >> 32);
+	}
+
+	return sizeof(*data) * 2;
 }
 
+#ifdef CONFIG_MODULES
 /* Update list and generate events when modules are unloaded. */
 static int gcov_module_notifier(struct notifier_block *nb, unsigned long event,
 				void *data)
 {
 	struct module *mod = data;
-	struct gcov_info *info;
-	struct gcov_info *prev;
+	struct gcov_info *info = NULL;
+	struct gcov_info *prev = NULL;
 
 	if (event != MODULE_STATE_GOING)
 		return NOTIFY_OK;
 	mutex_lock(&gcov_lock);
-	prev = NULL;
+
 	/* Remove entries located in module from linked list. */
-	for (info = gcov_info_head; info; info = info->next) {
-		if (within(info, mod->module_core, mod->core_size)) {
-			if (prev)
-				prev->next = info->next;
-			else
-				gcov_info_head = info->next;
+	while ((info = gcov_info_next(info))) {
+		if (gcov_info_within_module(info, mod)) {
+			gcov_info_unlink(prev, info);
 			if (gcov_events_enabled)
 				gcov_event(GCOV_REMOVE, info);
 		} else
 			prev = info;
 	}
+
 	mutex_unlock(&gcov_lock);
 
 	return NOTIFY_OK;