From 048cd5888f81713af4597bde5815f32d58fdf5b0 Mon Sep 17 00:00:00 2001 From: David John Date: Thu, 23 Oct 2008 13:55:56 +0530 Subject: [PATCH] RTC: Remove the BKL. Remove calls to the BKL since concurrent access is protected by the spin lock rtc_lock. Signed-off-by: David John Cc: Ingo Molnar Signed-off-by: Jonathan Corbet --- drivers/char/rtc.c | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) diff --git a/drivers/char/rtc.c b/drivers/char/rtc.c index 20d6efb6324e..e0d0f8b2696b 100644 --- a/drivers/char/rtc.c +++ b/drivers/char/rtc.c @@ -48,9 +48,10 @@ * CONFIG_HPET_EMULATE_RTC * 1.12a Maciej W. Rozycki: Handle memory-mapped chips properly. * 1.12ac Alan Cox: Allow read access to the day of week register + * 1.12b David John: Remove calls to the BKL. */ -#define RTC_VERSION "1.12ac" +#define RTC_VERSION "1.12b" /* * Note that *all* calls to CMOS_READ and CMOS_WRITE are done with @@ -73,7 +74,6 @@ #include #include #include -#include #include #include #include @@ -182,8 +182,8 @@ static int rtc_proc_open(struct inode *inode, struct file *file); /* * rtc_status is never changed by rtc_interrupt, and ioctl/open/close is - * protected by the big kernel lock. However, ioctl can still disable the timer - * in rtc_status and then with del_timer after the interrupt has read + * protected by the spin lock rtc_lock. However, ioctl can still disable the + * timer in rtc_status and then with del_timer after the interrupt has read * rtc_status but before mod_timer is called, which would then reenable the * timer (but you would need to have an awful timing before you'd trip on it) */ @@ -720,9 +720,7 @@ static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel) static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { long ret; - lock_kernel(); ret = rtc_do_ioctl(cmd, arg, 0); - unlock_kernel(); return ret; } @@ -731,12 +729,8 @@ static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) * Also clear the previous interrupt data on an open, and clean * up things on a close. */ - -/* We use rtc_lock to protect against concurrent opens. So the BKL is not - * needed here. Or anywhere else in this driver. */ static int rtc_open(struct inode *inode, struct file *file) { - lock_kernel(); spin_lock_irq(&rtc_lock); if (rtc_status & RTC_IS_OPEN) @@ -746,12 +740,10 @@ static int rtc_open(struct inode *inode, struct file *file) rtc_irq_data = 0; spin_unlock_irq(&rtc_lock); - unlock_kernel(); return 0; out_busy: spin_unlock_irq(&rtc_lock); - unlock_kernel(); return -EBUSY; } @@ -800,7 +792,6 @@ no_irq: } #ifdef RTC_IRQ -/* Called without the kernel lock - fine */ static unsigned int rtc_poll(struct file *file, poll_table *wait) { unsigned long l; -- 2.34.1