gcov: move gcov structs definitions to a gcc version specific file
authorFrantisek Hrbata <fhrbata@redhat.com>
Tue, 12 Nov 2013 23:11:24 +0000 (15:11 -0800)
committerBen Hutchings <ben@decadent.org.uk>
Mon, 19 Mar 2018 18:58:23 +0000 (18:58 +0000)
commit 8cbce376e3fdf4a21f59365aefbb52eac3c2e312 upstream.

Since also the gcov structures(gcov_info, gcov_fn_info, gcov_ctr_info) can
change between gcc releases, as shown in gcc 4.7, they cannot be defined
in a common header and need to be moved to a specific gcc implemention
file.  This also requires to make the gcov_info structure opaque for the
common code and to introduce simple helpers for accessing data inside
gcov_info.

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Acked-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Gospodarek <agospoda@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
kernel/gcov/base.c
kernel/gcov/fs.c
kernel/gcov/gcc_3_4.c
kernel/gcov/gcov.h

index 9b22d03..912576a 100644 (file)
@@ -20,7 +20,6 @@
 #include <linux/mutex.h>
 #include "gcov.h"
 
-static struct gcov_info *gcov_info_head;
 static int gcov_events_enabled;
 static DEFINE_MUTEX(gcov_lock);
 
@@ -34,7 +33,7 @@ void __gcov_init(struct gcov_info *info)
 
        mutex_lock(&gcov_lock);
        if (gcov_version == 0) {
-               gcov_version = info->version;
+               gcov_version = gcov_info_version(info);
                /*
                 * Printing gcc's version magic may prove useful for debugging
                 * incompatibility reports.
@@ -45,8 +44,7 @@ void __gcov_init(struct gcov_info *info)
         * Add new profiling data structure to list and inform event
         * listener.
         */
-       info->next = gcov_info_head;
-       gcov_info_head = info;
+       gcov_info_link(info);
        if (gcov_events_enabled)
                gcov_event(GCOV_ADD, info);
        mutex_unlock(&gcov_lock);
@@ -91,13 +89,15 @@ EXPORT_SYMBOL(__gcov_merge_delta);
  */
 void gcov_enable_events(void)
 {
-       struct gcov_info *info;
+       struct gcov_info *info = NULL;
 
        mutex_lock(&gcov_lock);
        gcov_events_enabled = 1;
+
        /* Perform event callback for previously registered entries. */
-       for (info = gcov_info_head; info; info = info->next)
+       while ((info = gcov_info_next(info)))
                gcov_event(GCOV_ADD, info);
+
        mutex_unlock(&gcov_lock);
 }
 
@@ -112,25 +112,23 @@ 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) {
+       while ((info = gcov_info_next(info))) {
                if (within(info, mod->module_core, mod->core_size)) {
-                       if (prev)
-                               prev->next = info->next;
-                       else
-                               gcov_info_head = info->next;
+                       gcov_info_unlink(prev, info);
                        if (gcov_events_enabled)
                                gcov_event(GCOV_REMOVE, info);
                } else
                        prev = info;
        }
+
        mutex_unlock(&gcov_lock);
 
        return NOTIFY_OK;
index 9bd0934..27e12ce 100644 (file)
@@ -242,7 +242,7 @@ static struct gcov_node *get_node_by_name(const char *name)
 
        list_for_each_entry(node, &all_head, all) {
                info = get_node_info(node);
-               if (info && (strcmp(info->filename, name) == 0))
+               if (info && (strcmp(gcov_info_filename(info), name) == 0))
                        return node;
        }
 
@@ -279,7 +279,7 @@ static ssize_t gcov_seq_write(struct file *file, const char __user *addr,
        seq = file->private_data;
        info = gcov_iter_get_info(seq->private);
        mutex_lock(&node_lock);
-       node = get_node_by_name(info->filename);
+       node = get_node_by_name(gcov_info_filename(info));
        if (node) {
                /* Reset counts or remove node for unloaded modules. */
                if (node->num_loaded == 0)
@@ -376,8 +376,9 @@ static void add_links(struct gcov_node *node, struct dentry *parent)
        if (!node->links)
                return;
        for (i = 0; i < num; i++) {
-               target = get_link_target(get_node_info(node)->filename,
-                                        &gcov_link[i]);
+               target = get_link_target(
+                               gcov_info_filename(get_node_info(node)),
+                               &gcov_link[i]);
                if (!target)
                        goto out_err;
                basename = strrchr(target, '/');
@@ -576,7 +577,7 @@ static void add_node(struct gcov_info *info)
        struct gcov_node *parent;
        struct gcov_node *node;
 
-       filename = kstrdup(info->filename, GFP_KERNEL);
+       filename = kstrdup(gcov_info_filename(info), GFP_KERNEL);
        if (!filename)
                return;
        parent = &root_node;
@@ -631,7 +632,7 @@ static void add_info(struct gcov_node *node, struct gcov_info *info)
        loaded_info = kcalloc(num + 1, sizeof(struct gcov_info *), GFP_KERNEL);
        if (!loaded_info) {
                pr_warning("could not add '%s' (out of memory)\n",
-                          info->filename);
+                          gcov_info_filename(info));
                return;
        }
        memcpy(loaded_info, node->loaded_info,
@@ -645,7 +646,8 @@ static void add_info(struct gcov_node *node, struct gcov_info *info)
                 */
                if (!gcov_info_is_compatible(node->unloaded_info, info)) {
                        pr_warning("discarding saved data for %s "
-                                  "(incompatible version)\n", info->filename);
+                                  "(incompatible version)\n",
+                                  gcov_info_filename(info));
                        gcov_info_free(node->unloaded_info);
                        node->unloaded_info = NULL;
                }
@@ -656,7 +658,7 @@ static void add_info(struct gcov_node *node, struct gcov_info *info)
                 */
                if (!gcov_info_is_compatible(node->loaded_info[0], info)) {
                        pr_warning("could not add '%s' (incompatible "
-                                  "version)\n", info->filename);
+                                  "version)\n", gcov_info_filename(info));
                        kfree(loaded_info);
                        return;
                }
@@ -692,7 +694,8 @@ static void save_info(struct gcov_node *node, struct gcov_info *info)
                node->unloaded_info = gcov_info_dup(info);
                if (!node->unloaded_info) {
                        pr_warning("could not save data for '%s' "
-                                  "(out of memory)\n", info->filename);
+                                  "(out of memory)\n",
+                                  gcov_info_filename(info));
                }
        }
 }
@@ -708,7 +711,7 @@ static void remove_info(struct gcov_node *node, struct gcov_info *info)
        i = get_info_index(node, info);
        if (i < 0) {
                pr_warning("could not remove '%s' (not found)\n",
-                          info->filename);
+                          gcov_info_filename(info));
                return;
        }
        if (gcov_persist)
@@ -735,7 +738,7 @@ void gcov_event(enum gcov_action action, struct gcov_info *info)
        struct gcov_node *node;
 
        mutex_lock(&node_lock);
-       node = get_node_by_name(info->filename);
+       node = get_node_by_name(gcov_info_filename(info));
        switch (action) {
        case GCOV_ADD:
                if (node)
@@ -748,7 +751,7 @@ void gcov_event(enum gcov_action action, struct gcov_info *info)
                        remove_info(node, info);
                else {
                        pr_warning("could not remove '%s' (not found)\n",
-                                  info->filename);
+                                  gcov_info_filename(info));
                }
                break;
        }
index ae5bb42..27bc88a 100644 (file)
 #include <linux/vmalloc.h>
 #include "gcov.h"
 
+#define GCOV_COUNTERS          5
+
+static struct gcov_info *gcov_info_head;
+
+/**
+ * struct gcov_fn_info - profiling meta data per function
+ * @ident: object file-unique function identifier
+ * @checksum: function checksum
+ * @n_ctrs: number of values per counter type belonging to this function
+ *
+ * This data is generated by gcc during compilation and doesn't change
+ * at run-time.
+ */
+struct gcov_fn_info {
+       unsigned int ident;
+       unsigned int checksum;
+       unsigned int n_ctrs[0];
+};
+
+/**
+ * struct gcov_ctr_info - profiling data per counter type
+ * @num: number of counter values for this type
+ * @values: array of counter values for this type
+ * @merge: merge function for counter values of this type (unused)
+ *
+ * This data is generated by gcc during compilation and doesn't change
+ * at run-time with the exception of the values array.
+ */
+struct gcov_ctr_info {
+       unsigned int    num;
+       gcov_type       *values;
+       void            (*merge)(gcov_type *, unsigned int);
+};
+
+/**
+ * struct gcov_info - profiling data per object file
+ * @version: gcov version magic indicating the gcc version used for compilation
+ * @next: list head for a singly-linked list
+ * @stamp: time stamp
+ * @filename: name of the associated gcov data file
+ * @n_functions: number of instrumented functions
+ * @functions: function data
+ * @ctr_mask: mask specifying which counter types are active
+ * @counts: counter data per counter type
+ *
+ * This data is generated by gcc during compilation and doesn't change
+ * at run-time with the exception of the next pointer.
+ */
+struct gcov_info {
+       unsigned int                    version;
+       struct gcov_info                *next;
+       unsigned int                    stamp;
+       const char                      *filename;
+       unsigned int                    n_functions;
+       const struct gcov_fn_info       *functions;
+       unsigned int                    ctr_mask;
+       struct gcov_ctr_info            counts[0];
+};
+
+/**
+ * gcov_info_filename - return info filename
+ * @info: profiling data set
+ */
+const char *gcov_info_filename(struct gcov_info *info)
+{
+       return info->filename;
+}
+
+/**
+ * gcov_info_version - return info version
+ * @info: profiling data set
+ */
+unsigned int gcov_info_version(struct gcov_info *info)
+{
+       return info->version;
+}
+
+/**
+ * gcov_info_next - return next profiling data set
+ * @info: profiling data set
+ *
+ * Returns next gcov_info following @info or first gcov_info in the chain if
+ * @info is %NULL.
+ */
+struct gcov_info *gcov_info_next(struct gcov_info *info)
+{
+       if (!info)
+               return gcov_info_head;
+
+       return info->next;
+}
+
+/**
+ * gcov_info_link - link/add profiling data set to the list
+ * @info: profiling data set
+ */
+void gcov_info_link(struct gcov_info *info)
+{
+       info->next = gcov_info_head;
+       gcov_info_head = info;
+}
+
+/**
+ * gcov_info_unlink - unlink/remove profiling data set from the list
+ * @prev: previous profiling data set
+ * @info: profiling data set
+ */
+void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info)
+{
+       if (prev)
+               prev->next = info->next;
+       else
+               gcov_info_head = info->next;
+}
+
 /* Symbolic links to be created for each profiling data file. */
 const struct gcov_link gcov_link[] = {
        { OBJ_TREE, "gcno" },   /* Link to .gcno file in $(objtree). */
index 060073e..92c8e22 100644 (file)
@@ -21,7 +21,6 @@
  * gcc and need to be kept as close to the original definition as possible to
  * remain compatible.
  */
-#define GCOV_COUNTERS          5
 #define GCOV_DATA_MAGIC                ((unsigned int) 0x67636461)
 #define GCOV_TAG_FUNCTION      ((unsigned int) 0x01000000)
 #define GCOV_TAG_COUNTER_BASE  ((unsigned int) 0x01a10000)
@@ -34,60 +33,18 @@ typedef long gcov_type;
 typedef long long gcov_type;
 #endif
 
-/**
- * struct gcov_fn_info - profiling meta data per function
- * @ident: object file-unique function identifier
- * @checksum: function checksum
- * @n_ctrs: number of values per counter type belonging to this function
- *
- * This data is generated by gcc during compilation and doesn't change
- * at run-time.
- */
-struct gcov_fn_info {
-       unsigned int ident;
-       unsigned int checksum;
-       unsigned int n_ctrs[0];
-};
-
-/**
- * struct gcov_ctr_info - profiling data per counter type
- * @num: number of counter values for this type
- * @values: array of counter values for this type
- * @merge: merge function for counter values of this type (unused)
- *
- * This data is generated by gcc during compilation and doesn't change
- * at run-time with the exception of the values array.
- */
-struct gcov_ctr_info {
-       unsigned int    num;
-       gcov_type       *values;
-       void            (*merge)(gcov_type *, unsigned int);
-};
+/* Opaque gcov_info. The gcov structures can change as for example in gcc 4.7 so
+ * we cannot use full definition here and they need to be placed in gcc specific
+ * implementation of gcov. This also means no direct access to the members in
+ * generic code and usage of the interface below.*/
+struct gcov_info;
 
-/**
- * struct gcov_info - profiling data per object file
- * @version: gcov version magic indicating the gcc version used for compilation
- * @next: list head for a singly-linked list
- * @stamp: time stamp
- * @filename: name of the associated gcov data file
- * @n_functions: number of instrumented functions
- * @functions: function data
- * @ctr_mask: mask specifying which counter types are active
- * @counts: counter data per counter type
- *
- * This data is generated by gcc during compilation and doesn't change
- * at run-time with the exception of the next pointer.
- */
-struct gcov_info {
-       unsigned int                    version;
-       struct gcov_info                *next;
-       unsigned int                    stamp;
-       const char                      *filename;
-       unsigned int                    n_functions;
-       const struct gcov_fn_info       *functions;
-       unsigned int                    ctr_mask;
-       struct gcov_ctr_info            counts[0];
-};
+/* Interface to access gcov_info data  */
+const char *gcov_info_filename(struct gcov_info *info);
+unsigned int gcov_info_version(struct gcov_info *info);
+struct gcov_info *gcov_info_next(struct gcov_info *info);
+void gcov_info_link(struct gcov_info *info);
+void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info);
 
 /* Base interface. */
 enum gcov_action {