1 files changed, 94 insertions, 0 deletions

diff --git a/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.24/0082-timekeeping-Provide-hrtimer-update-function.patch b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.24/0082-timekeeping-Provide-hrtimer-update-function.patch
new file mode 100644
index 00000000..a9735408
--- /dev/null
+++ b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.24/0082-timekeeping-Provide-hrtimer-update-function.patch
@@ -0,0 +1,94 @@
+From d6cadfb2bf29a5913562d3f63c49a937bc98540d Mon Sep 17 00:00:00 2001
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Tue, 10 Jul 2012 18:43:24 -0400
+Subject: [PATCH 082/109] timekeeping: Provide hrtimer update function
+
+This is a backport of f6c06abfb3972ad4914cef57d8348fcb2932bc3b
+
+To finally fix the infamous leap second issue and other race windows
+caused by functions which change the offsets between the various time
+bases (CLOCK_MONOTONIC, CLOCK_REALTIME and CLOCK_BOOTTIME) we need a
+function which atomically gets the current monotonic time and updates
+the offsets of CLOCK_REALTIME and CLOCK_BOOTTIME with minimalistic
+overhead. The previous patch which provides ktime_t offsets allows us
+to make this function almost as cheap as ktime_get() which is going to
+be replaced in hrtimer_interrupt().
+
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+Reviewed-by: Ingo Molnar <mingo@kernel.org>
+Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
+Acked-by: Prarit Bhargava <prarit@redhat.com>
+Signed-off-by: John Stultz <johnstul@us.ibm.com>
+Link: http://lkml.kernel.org/r/1341960205-56738-7-git-send-email-johnstul@us.ibm.com
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+[John Stultz: Backported to 3.2]
+Cc: Prarit Bhargava <prarit@redhat.com>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Cc: Linux Kernel <linux-kernel@vger.kernel.org>
+Signed-off-by: John Stultz <johnstul@us.ibm.com>
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+---
+ include/linux/hrtimer.h   |    1 +
+ kernel/time/timekeeping.c |   34 ++++++++++++++++++++++++++++++++++
+ 2 files changed, 35 insertions(+), 0 deletions(-)
+
+diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
+index c9ec940..cc07d27 100644
+--- a/include/linux/hrtimer.h
++++ b/include/linux/hrtimer.h
+@@ -327,6 +327,7 @@ extern ktime_t ktime_get(void);
+ extern ktime_t ktime_get_real(void);
+ extern ktime_t ktime_get_boottime(void);
+ extern ktime_t ktime_get_monotonic_offset(void);
++extern ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot);
+ 
+ DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
+ 
+diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
+index d5d0e5d..4938c5e 100644
+--- a/kernel/time/timekeeping.c
++++ b/kernel/time/timekeeping.c
+@@ -1240,6 +1240,40 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
+        } while (read_seqretry(&xtime_lock, seq));
+ }
+ 
++#ifdef CONFIG_HIGH_RES_TIMERS
++/**
++ * ktime_get_update_offsets - hrtimer helper
++ * @real:      pointer to storage for monotonic -> realtime offset
++ * @_boot:     pointer to storage for monotonic -> boottime offset
++ *
++ * Returns current monotonic time and updates the offsets
++ * Called from hrtimer_interupt() or retrigger_next_event()
++ */
++ktime_t ktime_get_update_offsets(ktime_t *real, ktime_t *boot)
++{
++       ktime_t now;
++       unsigned int seq;
++       u64 secs, nsecs;
++
++       do {
++               seq = read_seqbegin(&xtime_lock);
++
++               secs = xtime.tv_sec;
++               nsecs = xtime.tv_nsec;
++               nsecs += timekeeping_get_ns();
++               /* If arch requires, add in gettimeoffset() */
++               nsecs += arch_gettimeoffset();
++
++               *real = offs_real;
++               *boot = offs_boot;
++       } while (read_seqretry(&xtime_lock, seq));
++
++       now = ktime_add_ns(ktime_set(secs, 0), nsecs);
++       now = ktime_sub(now, *real);
++       return now;
++}
++#endif
++
+ /**
+  * ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format
+  */
+-- 
+1.7.7.6
+