diff mbox

drm/omap: Replace list_for_each with list_for_each_entry

Message ID 20171014200942.27388-1-harshasharmaiitr@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

harsha sharma Oct. 14, 2017, 8:09 p.m. UTC 
Replace use of list_for_each with list_for_each_entry to simplify the
code and remove variables that are used only in list_for_each.
Done with following coccinelle patch:

@r@
identifier fn,i,f,p;
expression e;
iterator name list_for_each, list_for_each_entry;
type T;
@@

fn(...) {
++ T *i;
  <+...
- list_for_each(p,e)
+ list_for_each_entry(i,e,f)
  {
	      ...
-   T *i = list_entry(p,T,f);
	          ...
   }
   ...+>
}

@@
identifier r.fn,r.p;
@@

fn(...) {
  ...
- struct list_head *p;
  ... when != p
}

@@
identifier r.fn,r.i,r.f;
expression r.e;
statement S;
@@

fn(...) {
  <...
  list_for_each_entry(i,e,f)
- {
  S
- }
  ...>
}

@s@
identifier i,f,p;
expression e;
type T;
@@

- list_for_each(p,e)
+ list_for_each_entry(i,e,f)
  {
    ... when != T *i;
-   i = list_entry(p,T,f);
    ...
  }

@@
identifier s.p;
@@

- struct list_head *p;
  ... when != p

@@
identifier s.i,s.f;
expression s.e;
statement S;
@@

  list_for_each_entry(i,e,f)
- {
  S
- }

Signed-off-by: Harsha Sharma <harshasharmaiitr@gmail.com>
---
 drivers/gpu/drm/omapdrm/dss/display.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

Comments

kernel test robot Oct. 16, 2017, 9:06 p.m. UTC | #1 
Hi Harsha,

[auto build test ERROR on drm/drm-next]
[also build test ERROR on v4.14-rc5 next-20171013]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Harsha-Sharma/drm-omap-Replace-list_for_each-with-list_for_each_entry/20171017-014028
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
config: arm-allmodconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=arm 

All error/warnings (new ones prefixed by >>):

   In file included from include/linux/linkage.h:4:0,
                    from include/linux/kernel.h:6,
                    from drivers/gpu//drm/omapdrm/dss/display.c:25:
   drivers/gpu//drm/omapdrm/dss/display.c: In function 'omapdss_register_display':
>> include/linux/list.h:463:43: error: dereferencing pointer to incomplete type 'struct omp_dss_device'
     for (pos = list_first_entry(head, typeof(*pos), member); \
                                               
   include/linux/compiler.h:553:19: note: in definition of macro '__compiletime_assert'
      bool __cond = !(condition);    \
                      ^~~~~~~~~
   include/linux/compiler.h:576:2: note: in expansion of macro '_compiletime_assert'
     _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
     ^~~~~~~~~~~~~~~~~~~
   include/linux/build_bug.h:46:37: note: in expansion of macro 'compiletime_assert'
    #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
                                        ^~~~~~~~~~~~~~~~~~
   include/linux/kernel.h:870:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
     BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \
     ^~~~~~~~~~~~~~~~
   include/linux/kernel.h:870:20: note: in expansion of macro '__same_type'
     BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \
                       ^~~~~~~~~~~
>> include/linux/list.h:365:2: note: in expansion of macro 'container_of'
     container_of(ptr, type, member)
     ^~~~~~~~~~~~
>> include/linux/list.h:376:2: note: in expansion of macro 'list_entry'
     list_entry((ptr)->next, type, member)
     ^~~~~~~~~~
>> include/linux/list.h:463:13: note: in expansion of macro 'list_first_entry'
     for (pos = list_first_entry(head, typeof(*pos), member); \
                ^~~~~~~~~~~~~~~~
>> drivers/gpu//drm/omapdrm/dss/display.c:71:2: note: in expansion of macro 'list_for_each_entry'
     list_for_each_entry(ldev, &panel_list, panel_list)
     ^~~~~~~~~~~~~~~~~~~
--
   In file included from include/linux/linkage.h:4:0,
                    from include/linux/kernel.h:6,
                    from drivers/gpu/drm/omapdrm/dss/display.c:25:
   drivers/gpu/drm/omapdrm/dss/display.c: In function 'omapdss_register_display':
>> include/linux/list.h:463:43: error: dereferencing pointer to incomplete type 'struct omp_dss_device'
     for (pos = list_first_entry(head, typeof(*pos), member); \
                                               
   include/linux/compiler.h:553:19: note: in definition of macro '__compiletime_assert'
      bool __cond = !(condition);    \
                      ^~~~~~~~~
   include/linux/compiler.h:576:2: note: in expansion of macro '_compiletime_assert'
     _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
     ^~~~~~~~~~~~~~~~~~~
   include/linux/build_bug.h:46:37: note: in expansion of macro 'compiletime_assert'
    #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
                                        ^~~~~~~~~~~~~~~~~~
   include/linux/kernel.h:870:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
     BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \
     ^~~~~~~~~~~~~~~~
   include/linux/kernel.h:870:20: note: in expansion of macro '__same_type'
     BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \
                       ^~~~~~~~~~~
>> include/linux/list.h:365:2: note: in expansion of macro 'container_of'
     container_of(ptr, type, member)
     ^~~~~~~~~~~~
>> include/linux/list.h:376:2: note: in expansion of macro 'list_entry'
     list_entry((ptr)->next, type, member)
     ^~~~~~~~~~
>> include/linux/list.h:463:13: note: in expansion of macro 'list_first_entry'
     for (pos = list_first_entry(head, typeof(*pos), member); \
                ^~~~~~~~~~~~~~~~
   drivers/gpu/drm/omapdrm/dss/display.c:71:2: note: in expansion of macro 'list_for_each_entry'
     list_for_each_entry(ldev, &panel_list, panel_list)
     ^~~~~~~~~~~~~~~~~~~

vim +463 include/linux/list.h

^1da177e Linus Torvalds  2005-04-16  357  
^1da177e Linus Torvalds  2005-04-16  358  /**
^1da177e Linus Torvalds  2005-04-16  359   * list_entry - get the struct for this entry
^1da177e Linus Torvalds  2005-04-16  360   * @ptr:	the &struct list_head pointer.
^1da177e Linus Torvalds  2005-04-16  361   * @type:	the type of the struct this is embedded in.
3943f42c Andrey Utkin    2014-11-14  362   * @member:	the name of the list_head within the struct.
^1da177e Linus Torvalds  2005-04-16  363   */
^1da177e Linus Torvalds  2005-04-16  364  #define list_entry(ptr, type, member) \
^1da177e Linus Torvalds  2005-04-16 @365  	container_of(ptr, type, member)
^1da177e Linus Torvalds  2005-04-16  366  
^1da177e Linus Torvalds  2005-04-16  367  /**
b5e61818 Pavel Emelianov 2007-05-08  368   * list_first_entry - get the first element from a list
b5e61818 Pavel Emelianov 2007-05-08  369   * @ptr:	the list head to take the element from.
b5e61818 Pavel Emelianov 2007-05-08  370   * @type:	the type of the struct this is embedded in.
3943f42c Andrey Utkin    2014-11-14  371   * @member:	the name of the list_head within the struct.
b5e61818 Pavel Emelianov 2007-05-08  372   *
b5e61818 Pavel Emelianov 2007-05-08  373   * Note, that list is expected to be not empty.
b5e61818 Pavel Emelianov 2007-05-08  374   */
b5e61818 Pavel Emelianov 2007-05-08  375  #define list_first_entry(ptr, type, member) \
b5e61818 Pavel Emelianov 2007-05-08 @376  	list_entry((ptr)->next, type, member)
b5e61818 Pavel Emelianov 2007-05-08  377  
b5e61818 Pavel Emelianov 2007-05-08  378  /**
93be3c2e Oleg Nesterov   2013-11-12  379   * list_last_entry - get the last element from a list
93be3c2e Oleg Nesterov   2013-11-12  380   * @ptr:	the list head to take the element from.
93be3c2e Oleg Nesterov   2013-11-12  381   * @type:	the type of the struct this is embedded in.
3943f42c Andrey Utkin    2014-11-14  382   * @member:	the name of the list_head within the struct.
93be3c2e Oleg Nesterov   2013-11-12  383   *
93be3c2e Oleg Nesterov   2013-11-12  384   * Note, that list is expected to be not empty.
93be3c2e Oleg Nesterov   2013-11-12  385   */
93be3c2e Oleg Nesterov   2013-11-12  386  #define list_last_entry(ptr, type, member) \
93be3c2e Oleg Nesterov   2013-11-12  387  	list_entry((ptr)->prev, type, member)
93be3c2e Oleg Nesterov   2013-11-12  388  
93be3c2e Oleg Nesterov   2013-11-12  389  /**
6d7581e6 Jiri Pirko      2013-05-29  390   * list_first_entry_or_null - get the first element from a list
6d7581e6 Jiri Pirko      2013-05-29  391   * @ptr:	the list head to take the element from.
6d7581e6 Jiri Pirko      2013-05-29  392   * @type:	the type of the struct this is embedded in.
3943f42c Andrey Utkin    2014-11-14  393   * @member:	the name of the list_head within the struct.
6d7581e6 Jiri Pirko      2013-05-29  394   *
6d7581e6 Jiri Pirko      2013-05-29  395   * Note that if the list is empty, it returns NULL.
6d7581e6 Jiri Pirko      2013-05-29  396   */
12adfd88 Chris Wilson    2016-07-23  397  #define list_first_entry_or_null(ptr, type, member) ({ \
12adfd88 Chris Wilson    2016-07-23  398  	struct list_head *head__ = (ptr); \
12adfd88 Chris Wilson    2016-07-23  399  	struct list_head *pos__ = READ_ONCE(head__->next); \
12adfd88 Chris Wilson    2016-07-23  400  	pos__ != head__ ? list_entry(pos__, type, member) : NULL; \
12adfd88 Chris Wilson    2016-07-23  401  })
6d7581e6 Jiri Pirko      2013-05-29  402  
6d7581e6 Jiri Pirko      2013-05-29  403  /**
008208c6 Oleg Nesterov   2013-11-12  404   * list_next_entry - get the next element in list
008208c6 Oleg Nesterov   2013-11-12  405   * @pos:	the type * to cursor
3943f42c Andrey Utkin    2014-11-14  406   * @member:	the name of the list_head within the struct.
008208c6 Oleg Nesterov   2013-11-12  407   */
008208c6 Oleg Nesterov   2013-11-12  408  #define list_next_entry(pos, member) \
008208c6 Oleg Nesterov   2013-11-12  409  	list_entry((pos)->member.next, typeof(*(pos)), member)
008208c6 Oleg Nesterov   2013-11-12  410  
008208c6 Oleg Nesterov   2013-11-12  411  /**
008208c6 Oleg Nesterov   2013-11-12  412   * list_prev_entry - get the prev element in list
008208c6 Oleg Nesterov   2013-11-12  413   * @pos:	the type * to cursor
3943f42c Andrey Utkin    2014-11-14  414   * @member:	the name of the list_head within the struct.
008208c6 Oleg Nesterov   2013-11-12  415   */
008208c6 Oleg Nesterov   2013-11-12  416  #define list_prev_entry(pos, member) \
008208c6 Oleg Nesterov   2013-11-12  417  	list_entry((pos)->member.prev, typeof(*(pos)), member)
008208c6 Oleg Nesterov   2013-11-12  418  
008208c6 Oleg Nesterov   2013-11-12  419  /**
^1da177e Linus Torvalds  2005-04-16  420   * list_for_each	-	iterate over a list
8e3a67a9 Randy Dunlap    2006-06-25  421   * @pos:	the &struct list_head to use as a loop cursor.
^1da177e Linus Torvalds  2005-04-16  422   * @head:	the head for your list.
^1da177e Linus Torvalds  2005-04-16  423   */
^1da177e Linus Torvalds  2005-04-16  424  #define list_for_each(pos, head) \
e66eed65 Linus Torvalds  2011-05-19  425  	for (pos = (head)->next; pos != (head); pos = pos->next)
^1da177e Linus Torvalds  2005-04-16  426  
^1da177e Linus Torvalds  2005-04-16  427  /**
^1da177e Linus Torvalds  2005-04-16  428   * list_for_each_prev	-	iterate over a list backwards
8e3a67a9 Randy Dunlap    2006-06-25  429   * @pos:	the &struct list_head to use as a loop cursor.
^1da177e Linus Torvalds  2005-04-16  430   * @head:	the head for your list.
^1da177e Linus Torvalds  2005-04-16  431   */
^1da177e Linus Torvalds  2005-04-16  432  #define list_for_each_prev(pos, head) \
e66eed65 Linus Torvalds  2011-05-19  433  	for (pos = (head)->prev; pos != (head); pos = pos->prev)
^1da177e Linus Torvalds  2005-04-16  434  
^1da177e Linus Torvalds  2005-04-16  435  /**
^1da177e Linus Torvalds  2005-04-16  436   * list_for_each_safe - iterate over a list safe against removal of list entry
8e3a67a9 Randy Dunlap    2006-06-25  437   * @pos:	the &struct list_head to use as a loop cursor.
^1da177e Linus Torvalds  2005-04-16  438   * @n:		another &struct list_head to use as temporary storage
^1da177e Linus Torvalds  2005-04-16  439   * @head:	the head for your list.
^1da177e Linus Torvalds  2005-04-16  440   */
^1da177e Linus Torvalds  2005-04-16  441  #define list_for_each_safe(pos, n, head) \
^1da177e Linus Torvalds  2005-04-16  442  	for (pos = (head)->next, n = pos->next; pos != (head); \
^1da177e Linus Torvalds  2005-04-16  443  		pos = n, n = pos->next)
^1da177e Linus Torvalds  2005-04-16  444  
^1da177e Linus Torvalds  2005-04-16  445  /**
8f731f7d Randy Dunlap    2007-10-18  446   * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry
37c42524 Denis V. Lunev  2007-10-16  447   * @pos:	the &struct list_head to use as a loop cursor.
37c42524 Denis V. Lunev  2007-10-16  448   * @n:		another &struct list_head to use as temporary storage
37c42524 Denis V. Lunev  2007-10-16  449   * @head:	the head for your list.
37c42524 Denis V. Lunev  2007-10-16  450   */
37c42524 Denis V. Lunev  2007-10-16  451  #define list_for_each_prev_safe(pos, n, head) \
37c42524 Denis V. Lunev  2007-10-16  452  	for (pos = (head)->prev, n = pos->prev; \
e66eed65 Linus Torvalds  2011-05-19  453  	     pos != (head); \
37c42524 Denis V. Lunev  2007-10-16  454  	     pos = n, n = pos->prev)
37c42524 Denis V. Lunev  2007-10-16  455  
37c42524 Denis V. Lunev  2007-10-16  456  /**
^1da177e Linus Torvalds  2005-04-16  457   * list_for_each_entry	-	iterate over list of given type
8e3a67a9 Randy Dunlap    2006-06-25  458   * @pos:	the type * to use as a loop cursor.
^1da177e Linus Torvalds  2005-04-16  459   * @head:	the head for your list.
3943f42c Andrey Utkin    2014-11-14  460   * @member:	the name of the list_head within the struct.
^1da177e Linus Torvalds  2005-04-16  461   */
^1da177e Linus Torvalds  2005-04-16  462  #define list_for_each_entry(pos, head, member)				\
93be3c2e Oleg Nesterov   2013-11-12 @463  	for (pos = list_first_entry(head, typeof(*pos), member);	\
e66eed65 Linus Torvalds  2011-05-19  464  	     &pos->member != (head);					\
8120e2e5 Oleg Nesterov   2013-11-12  465  	     pos = list_next_entry(pos, member))
^1da177e Linus Torvalds  2005-04-16  466  

:::::: The code at line 463 was first introduced by commit
:::::: 93be3c2eb3371f022ad88acf1ab6bee8e3c38378 list: introduce list_last_entry(), use list_{first,last}_entry()

:::::: TO: Oleg Nesterov <oleg@redhat.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox

Patch

diff --git a/drivers/gpu/drm/omapdrm/dss/display.c b/drivers/gpu/drm/omapdrm/dss/display.c
index 42279933790e..e6f86026dd93 100644
--- a/drivers/gpu/drm/omapdrm/dss/display.c
+++ b/drivers/gpu/drm/omapdrm/dss/display.c
@@ -43,6 +43,7 @@  static int disp_num_counter;
 
 int omapdss_register_display(struct omap_dss_device *dssdev)
 {
+	struct omp_dss_device *ldev;
 	struct omap_dss_driver *drv = dssdev->driver;
 	struct list_head *cur;
 	int id;
@@ -67,13 +68,9 @@  int omapdss_register_display(struct omap_dss_device *dssdev)
 		drv->get_timings = omapdss_default_get_timings;
 
 	mutex_lock(&panel_list_mutex);
-	list_for_each(cur, &panel_list) {
-		struct omap_dss_device *ldev = list_entry(cur,
-							 struct omap_dss_device,
-							 panel_list);
+	list_for_each_entry(ldev, &panel_list, panel_list)
 		if (strcmp(ldev->alias, dssdev->alias) > 0)
 			break;
-	}
 	list_add_tail(&dssdev->panel_list, cur);
 	mutex_unlock(&panel_list_mutex);
 	return 0;
@@ -94,12 +91,11 @@  bool omapdss_component_is_display(struct device_node *node)
 	bool found = false;
 
 	mutex_lock(&panel_list_mutex);
-	list_for_each_entry(dssdev, &panel_list, panel_list) {
+	list_for_each_entry(dssdev, &panel_list, panel_list)
 		if (dssdev->dev->of_node == node) {
 			found = true;
 			goto out;
 		}
-	}
 out:
 	mutex_unlock(&panel_list_mutex);
 	return found;
@@ -152,8 +148,7 @@  struct omap_dss_device *omap_dss_get_next_device(struct omap_dss_device *from)
 
 	omap_dss_put_device(from);
 
-	list_for_each(l, &panel_list) {
-		dssdev = list_entry(l, struct omap_dss_device, panel_list);
+	list_for_each_entry(dssdev, &panel_list, panel_list)
 		if (dssdev == from) {
 			if (list_is_last(l, &panel_list)) {
 				dssdev = NULL;
@@ -165,7 +160,6 @@  struct omap_dss_device *omap_dss_get_next_device(struct omap_dss_device *from)
 			omap_dss_get_device(dssdev);
 			goto out;
 		}
-	}
 
 	WARN(1, "'from' dssdev not found\n");