path: root/drivers/char/ds1620.c
diff options
authorArnd Bergmann <arnd@arndb.de>2010-06-02 14:28:52 +0200
committerArnd Bergmann <arnd@arndb.de>2010-10-05 15:01:04 +0200
commit613655fa39ff6957754fa8ceb8559980920eb8ee (patch)
treead19600cb81207b24188683d7fc4ae88013339d1 /drivers/char/ds1620.c
parentipmi: autoconvert trivial BKL users to private mutex (diff)
drivers: autoconvert trivial BKL users to private mutex
All these files use the big kernel lock in a trivial way to serialize their private file operations, typically resulting from an earlier semi-automatic pushdown from VFS. None of these drivers appears to want to lock against other code, and they all use the BKL as the top-level lock in their file operations, meaning that there is no lock-order inversion problem. Consequently, we can remove the BKL completely, replacing it with a per-file mutex in every case. Using a scripted approach means we can avoid typos. These drivers do not seem to be under active maintainance from my brief investigation. Apologies to those maintainers that I have missed. file=$1 name=$2 if grep -q lock_kernel ${file} ; then if grep -q 'include.*linux.mutex.h' ${file} ; then sed -i '/include.*<linux\/smp_lock.h>/d' ${file} else sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file} fi sed -i ${file} \ -e "/^#include.*linux.mutex.h/,$ { 1,/^\(static\|int\|long\)/ { /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex); } }" \ -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \ -e '/[ ]*cycle_kernel_lock();/d' else sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/char/ds1620.c')
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/char/ds1620.c b/drivers/char/ds1620.c
index dbee8688f75c..9aa1fd059aea 100644
--- a/drivers/char/ds1620.c
+++ b/drivers/char/ds1620.c
@@ -8,7 +8,7 @@
#include <linux/proc_fs.h>
#include <linux/capability.h>
#include <linux/init.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <mach/hardware.h>
#include <asm/mach-types.h>
@@ -34,6 +34,7 @@
#define CFG_CPU 2
#define CFG_1SHOT 1
+static DEFINE_MUTEX(ds1620_mutex);
static const char *fan_state[] = { "off", "on", "on (hardwired)" };
@@ -210,7 +211,6 @@ static void ds1620_read_state(struct therm *therm)
static int ds1620_open(struct inode *inode, struct file *file)
- cycle_kernel_lock();
return nonseekable_open(inode, file);
@@ -321,9 +321,9 @@ ds1620_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
int ret;
- lock_kernel();
+ mutex_lock(&ds1620_mutex);
ret = ds1620_ioctl(file, cmd, arg);
- unlock_kernel();
+ mutex_unlock(&ds1620_mutex);
return ret;