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author | Arnd Bergmann <arnd@arndb.de> | 2010-06-02 14:28:52 +0200 |
---|---|---|
committer | Arnd Bergmann <arnd@arndb.de> | 2010-10-05 15:01:04 +0200 |
commit | 613655fa39ff6957754fa8ceb8559980920eb8ee (patch) | |
tree | ad19600cb81207b24188683d7fc4ae88013339d1 /drivers/rtc/rtc-m41t80.c | |
parent | 609146fdb319cebce93be550938ab852f7bade90 (diff) | |
download | linux-stable-613655fa39ff6957754fa8ceb8559980920eb8ee.tar.gz linux-stable-613655fa39ff6957754fa8ceb8559980920eb8ee.tar.bz2 linux-stable-613655fa39ff6957754fa8ceb8559980920eb8ee.zip |
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/rtc/rtc-m41t80.c')
-rw-r--r-- | drivers/rtc/rtc-m41t80.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c index d60557cae8ef..512dca16a42c 100644 --- a/drivers/rtc/rtc-m41t80.c +++ b/drivers/rtc/rtc-m41t80.c @@ -20,7 +20,7 @@ #include <linux/module.h> #include <linux/rtc.h> #include <linux/slab.h> -#include <linux/smp_lock.h> +#include <linux/mutex.h> #include <linux/string.h> #ifdef CONFIG_RTC_DRV_M41T80_WDT #include <linux/fs.h> @@ -68,6 +68,7 @@ #define DRV_VERSION "0.05" +static DEFINE_MUTEX(m41t80_rtc_mutex); static const struct i2c_device_id m41t80_id[] = { { "m41t62", M41T80_FEATURE_SQ | M41T80_FEATURE_SQ_ALT }, { "m41t65", M41T80_FEATURE_HT | M41T80_FEATURE_WD }, @@ -677,9 +678,9 @@ static long wdt_unlocked_ioctl(struct file *file, unsigned int cmd, { int ret; - lock_kernel(); + mutex_lock(&m41t80_rtc_mutex); ret = wdt_ioctl(file, cmd, arg); - unlock_kernel(); + mutex_unlock(&m41t80_rtc_mutex); return ret; } @@ -693,16 +694,16 @@ static long wdt_unlocked_ioctl(struct file *file, unsigned int cmd, static int wdt_open(struct inode *inode, struct file *file) { if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) { - lock_kernel(); + mutex_lock(&m41t80_rtc_mutex); if (test_and_set_bit(0, &wdt_is_open)) { - unlock_kernel(); + mutex_unlock(&m41t80_rtc_mutex); return -EBUSY; } /* * Activate */ wdt_is_open = 1; - unlock_kernel(); + mutex_unlock(&m41t80_rtc_mutex); return nonseekable_open(inode, file); } return -ENODEV; |