#include <linux/export.h>
#include <linux/init.h>
#include <linux/fs.h>
+#include <linux/minmax.h>
#include <linux/debugfs.h>
#include <asm/debug.h>
char *out_buf, const char *in_buf);
static int debug_sprintf_format_fn(debug_info_t *id, struct debug_view *view,
char *out_buf, debug_sprintf_entry_t *curr_event);
+static void debug_areas_swap(debug_info_t *a, debug_info_t *b);
+static void debug_events_append(debug_info_t *dest, debug_info_t *src);
/* globals */
goto out;
rc->mode = mode & ~S_IFMT;
-
- /* create root directory */
- rc->debugfs_root_entry = debugfs_create_dir(rc->name,
- debug_debugfs_root_entry);
-
- /* append new element to linked list */
- if (!debug_area_first) {
- /* first element in list */
- debug_area_first = rc;
- rc->prev = NULL;
- } else {
- /* append element to end of list */
- debug_area_last->next = rc;
- rc->prev = debug_area_last;
- }
- debug_area_last = rc;
- rc->next = NULL;
-
refcount_set(&rc->ref_count, 1);
out:
return rc;
*/
static void debug_info_put(debug_info_t *db_info)
{
- int i;
-
if (!db_info)
return;
- if (refcount_dec_and_test(&db_info->ref_count)) {
- for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
- if (!db_info->views[i])
- continue;
- debugfs_remove(db_info->debugfs_entries[i]);
- }
- debugfs_remove(db_info->debugfs_root_entry);
- if (db_info == debug_area_first)
- debug_area_first = db_info->next;
- if (db_info == debug_area_last)
- debug_area_last = db_info->prev;
- if (db_info->prev)
- db_info->prev->next = db_info->next;
- if (db_info->next)
- db_info->next->prev = db_info->prev;
+ if (refcount_dec_and_test(&db_info->ref_count))
debug_info_free(db_info);
- }
}
/*
return 0; /* success */
}
+/* Create debugfs entries and add to internal list. */
+static void _debug_register(debug_info_t *id)
+{
+ /* create root directory */
+ id->debugfs_root_entry = debugfs_create_dir(id->name,
+ debug_debugfs_root_entry);
+
+ /* append new element to linked list */
+ if (!debug_area_first) {
+ /* first element in list */
+ debug_area_first = id;
+ id->prev = NULL;
+ } else {
+ /* append element to end of list */
+ debug_area_last->next = id;
+ id->prev = debug_area_last;
+ }
+ debug_area_last = id;
+ id->next = NULL;
+
+ debug_register_view(id, &debug_level_view);
+ debug_register_view(id, &debug_flush_view);
+ debug_register_view(id, &debug_pages_view);
+}
+
/**
* debug_register_mode() - creates and initializes debug area.
*
if ((uid != 0) || (gid != 0))
pr_warn("Root becomes the owner of all s390dbf files in sysfs\n");
BUG_ON(!initialized);
- mutex_lock(&debug_mutex);
/* create new debug_info */
rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
- if (!rc)
- goto out;
- debug_register_view(rc, &debug_level_view);
- debug_register_view(rc, &debug_flush_view);
- debug_register_view(rc, &debug_pages_view);
-out:
- if (!rc)
+ if (rc) {
+ mutex_lock(&debug_mutex);
+ _debug_register(rc);
+ mutex_unlock(&debug_mutex);
+ } else {
pr_err("Registering debug feature %s failed\n", name);
- mutex_unlock(&debug_mutex);
+ }
return rc;
}
EXPORT_SYMBOL(debug_register_mode);
}
EXPORT_SYMBOL(debug_register);
+/**
+ * debug_register_static() - registers a static debug area
+ *
+ * @id: Handle for static debug area
+ * @pages_per_area: Number of pages per area
+ * @nr_areas: Number of debug areas
+ *
+ * Register debug_info_t defined using DEFINE_STATIC_DEBUG_INFO.
+ *
+ * Note: This function is called automatically via an initcall generated by
+ * DEFINE_STATIC_DEBUG_INFO.
+ */
+void debug_register_static(debug_info_t *id, int pages_per_area, int nr_areas)
+{
+ unsigned long flags;
+ debug_info_t *copy;
+
+ if (!initialized) {
+ pr_err("Tried to register debug feature %s too early\n",
+ id->name);
+ return;
+ }
+
+ copy = debug_info_alloc("", pages_per_area, nr_areas, id->buf_size,
+ id->level, ALL_AREAS);
+ if (!copy) {
+ pr_err("Registering debug feature %s failed\n", id->name);
+
+ /* Clear pointers to prevent tracing into released initdata. */
+ spin_lock_irqsave(&id->lock, flags);
+ id->areas = NULL;
+ id->active_pages = NULL;
+ id->active_entries = NULL;
+ spin_unlock_irqrestore(&id->lock, flags);
+
+ return;
+ }
+
+ /* Replace static trace area with dynamic copy. */
+ spin_lock_irqsave(&id->lock, flags);
+ debug_events_append(copy, id);
+ debug_areas_swap(id, copy);
+ spin_unlock_irqrestore(&id->lock, flags);
+
+ /* Clear pointers to initdata and discard copy. */
+ copy->areas = NULL;
+ copy->active_pages = NULL;
+ copy->active_entries = NULL;
+ debug_info_free(copy);
+
+ mutex_lock(&debug_mutex);
+ _debug_register(id);
+ mutex_unlock(&debug_mutex);
+}
+
+/* Remove debugfs entries and remove from internal list. */
+static void _debug_unregister(debug_info_t *id)
+{
+ int i;
+
+ for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
+ if (!id->views[i])
+ continue;
+ debugfs_remove(id->debugfs_entries[i]);
+ }
+ debugfs_remove(id->debugfs_root_entry);
+ if (id == debug_area_first)
+ debug_area_first = id->next;
+ if (id == debug_area_last)
+ debug_area_last = id->prev;
+ if (id->prev)
+ id->prev->next = id->next;
+ if (id->next)
+ id->next->prev = id->prev;
+}
+
/**
* debug_unregister() - give back debug area.
*
if (!id)
return;
mutex_lock(&debug_mutex);
- debug_info_put(id);
+ _debug_unregister(id);
mutex_unlock(&debug_mutex);
+
+ debug_info_put(id);
}
EXPORT_SYMBOL(debug_unregister);
*/
static int debug_set_size(debug_info_t *id, int nr_areas, int pages_per_area)
{
- debug_entry_t ***new_areas;
+ debug_info_t *new_id;
unsigned long flags;
- int rc = 0;
if (!id || (nr_areas <= 0) || (pages_per_area < 0))
return -EINVAL;
- if (pages_per_area > 0) {
- new_areas = debug_areas_alloc(pages_per_area, nr_areas);
- if (!new_areas) {
- pr_info("Allocating memory for %i pages failed\n",
- pages_per_area);
- rc = -ENOMEM;
- goto out;
- }
- } else {
- new_areas = NULL;
+
+ new_id = debug_info_alloc("", pages_per_area, nr_areas, id->buf_size,
+ id->level, ALL_AREAS);
+ if (!new_id) {
+ pr_info("Allocating memory for %i pages failed\n",
+ pages_per_area);
+ return -ENOMEM;
}
+
spin_lock_irqsave(&id->lock, flags);
- debug_areas_free(id);
- id->areas = new_areas;
- id->nr_areas = nr_areas;
- id->pages_per_area = pages_per_area;
- id->active_area = 0;
- memset(id->active_entries, 0, sizeof(int)*id->nr_areas);
- memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
+ debug_events_append(new_id, id);
+ debug_areas_swap(new_id, id);
+ debug_info_free(new_id);
spin_unlock_irqrestore(&id->lock, flags);
pr_info("%s: set new size (%i pages)\n", id->name, pages_per_area);
-out:
- return rc;
+
+ return 0;
}
/**
if (!id)
return;
- spin_lock_irqsave(&id->lock, flags);
+
if (new_level == DEBUG_OFF_LEVEL) {
- id->level = DEBUG_OFF_LEVEL;
pr_info("%s: switched off\n", id->name);
} else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
pr_info("%s: level %i is out of range (%i - %i)\n",
id->name, new_level, 0, DEBUG_MAX_LEVEL);
- } else {
- id->level = new_level;
+ return;
}
+
+ spin_lock_irqsave(&id->lock, flags);
+ id->level = new_level;
spin_unlock_irqrestore(&id->lock, flags);
}
EXPORT_SYMBOL(debug_set_level);
id->active_entries[id->active_area]);
}
+/* Swap debug areas of a and b. */
+static void debug_areas_swap(debug_info_t *a, debug_info_t *b)
+{
+ swap(a->nr_areas, b->nr_areas);
+ swap(a->pages_per_area, b->pages_per_area);
+ swap(a->areas, b->areas);
+ swap(a->active_area, b->active_area);
+ swap(a->active_pages, b->active_pages);
+ swap(a->active_entries, b->active_entries);
+}
+
+/* Append all debug events in active area from source to destination log. */
+static void debug_events_append(debug_info_t *dest, debug_info_t *src)
+{
+ debug_entry_t *from, *to, *last;
+
+ if (!src->areas || !dest->areas)
+ return;
+
+ /* Loop over all entries in src, starting with oldest. */
+ from = get_active_entry(src);
+ last = from;
+ do {
+ if (from->clock != 0LL) {
+ to = get_active_entry(dest);
+ memset(to, 0, dest->entry_size);
+ memcpy(to, from, min(src->entry_size,
+ dest->entry_size));
+ proceed_active_entry(dest);
+ }
+
+ proceed_active_entry(src);
+ from = get_active_entry(src);
+ } while (from != last);
+}
+
/*
* debug_finish_entry:
* - set timestamp, caller address, cpu number etc.
break;
}
if (i == DEBUG_MAX_VIEWS) {
- pr_err("Registering view %s/%s would exceed the maximum "
- "number of views %i\n", id->name, view->name, i);
rc = -1;
} else {
id->views[i] = view;
id->debugfs_entries[i] = pde;
}
spin_unlock_irqrestore(&id->lock, flags);
- if (rc)
+ if (rc) {
+ pr_err("Registering view %s/%s would exceed the maximum "
+ "number of views %i\n", id->name, view->name, i);
debugfs_remove(pde);
+ }
out:
return rc;
}
projects / linux-2.6-microblaze.git / blobdiff