AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-12-20 13:08:01 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity

tm6000: drop unnecessary list_empty

Browse Source 
list_for_each_entry is able to handle an empty list.
The only effect of avoiding the loop is not initializing the
index variable.
Drop list_empty tests in cases where these variables are not
used.

Note that list_for_each_entry is defined in terms of list_first_entry,
which indicates that it should not be used on an empty list.  But in
list_for_each_entry, the element obtained by list_first_entry is not
really accessed, only the address of its list_head field is compared
to the address of the list head, so the list_first_entry is safe.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

<smpl>
@@
expression x,e;
iterator name list_for_each_entry;
statement S;
identifier i;
@@

-if (!(list_empty(x))) {
   list_for_each_entry(i,x,...) S
- }
 ... when != i
? i = e
</smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Julia Lawall 2020-07-26 12:58:31 +02:00 committed by Mauro Carvalho Chehab
parent a357a78407
commit 3c9c3902e3
1 changed files with 9 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
drivers/media/usb/tm6000/tm6000-core.c
View File

@ -853,11 +853,9 @@ int tm6000_call_fillbuf(struct tm6000_core *dev, enum tm6000_ops_type type,
/* FIXME: tm6000_extension_devlist_lock should be a spinlock */
if (!list_empty(&tm6000_extension_devlist)) {
list_for_each_entry(ops, &tm6000_extension_devlist, next) {
if (ops->fillbuf && ops->type == type)
ops->fillbuf(dev, buf, size);
}
list_for_each_entry(ops, &tm6000_extension_devlist, next) {
if (ops->fillbuf && ops->type == type)
ops->fillbuf(dev, buf, size);
}
return 0;
@ -898,11 +896,9 @@ void tm6000_init_extension(struct tm6000_core *dev)
struct tm6000_ops *ops = NULL;
mutex_lock(&tm6000_devlist_mutex);
if (!list_empty(&tm6000_extension_devlist)) {
list_for_each_entry(ops, &tm6000_extension_devlist, next) {
if (ops->init)
ops->init(dev);
}
list_for_each_entry(ops, &tm6000_extension_devlist, next) {
if (ops->init)
ops->init(dev);
}
mutex_unlock(&tm6000_devlist_mutex);
}
@ -912,11 +908,9 @@ void tm6000_close_extension(struct tm6000_core *dev)
struct tm6000_ops *ops = NULL;
mutex_lock(&tm6000_devlist_mutex);
if (!list_empty(&tm6000_extension_devlist)) {
list_for_each_entry(ops, &tm6000_extension_devlist, next) {
if (ops->fini)
ops->fini(dev);
}
list_for_each_entry(ops, &tm6000_extension_devlist, next) {
if (ops->fini)
ops->fini(dev);
}
mutex_unlock(&tm6000_devlist_mutex);
}