Merge remote-tracking branch 'linus/master' into staging/for_v3.5

* linus/master: (805 commits)
  tty: Fix LED error return
  openvswitch: checking wrong variable in queue_userspace_packet()
  bonding: Fix LACPDU rx_dropped commit.
  Linux 3.4-rc7
  ARM: EXYNOS: fix ctrlbit for exynos5_clk_pdma1
  ARM: EXYNOS: use s5p-timer for UniversalC210 board
  ARM / mach-shmobile: Invalidate caches when booting secondary cores
  ARM / mach-shmobile: sh73a0 SMP TWD boot regression fix
  ARM / mach-shmobile: r8a7779 SMP TWD boot regression fix
  ARM: mach-shmobile: convert ag5evm to use the generic MMC GPIO hotplug helper
  ARM: mach-shmobile: convert mackerel to use the generic MMC GPIO hotplug helper
  MAINTAINERS: Add myself as the cpufreq maintainer
  dm mpath: check if scsi_dh module already loaded before trying to load
  dm thin: correct module description
  dm thin: fix unprotected use of prepared_discards list
  dm thin: reinstate missing mempool_free in cell_release_singleton
  gpio/exynos: Fix compiler warnings when non-exynos machines are selected
  gpio: pch9: Use proper flow type handlers
  powerpc/irq: Fix another case of lazy IRQ state getting out of sync
  ks8851: Update link status during link change interrupt
  ...

Conflicts:
	drivers/media/common/tuners/xc5000.c
	drivers/media/common/tuners/xc5000.h
	drivers/usb/gadget/uvc_queue.c

1 files changed, 22 insertions, 1 deletions

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index c6db9fb33c4..600060e25ec 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -141,7 +141,7 @@ static inline unsigned __read_seqcount_begin(const seqcount_t *s)
 	unsigned ret;
 
 repeat:
-	ret = s->sequence;
+	ret = ACCESS_ONCE(s->sequence);
 	if (unlikely(ret & 1)) {
 		cpu_relax();
 		goto repeat;
@@ -166,6 +166,27 @@ static inline unsigned read_seqcount_begin(const seqcount_t *s)
 }
 
 /**
+ * raw_seqcount_begin - begin a seq-read critical section
+ * @s: pointer to seqcount_t
+ * Returns: count to be passed to read_seqcount_retry
+ *
+ * raw_seqcount_begin opens a read critical section of the given seqcount.
+ * Validity of the critical section is tested by checking read_seqcount_retry
+ * function.
+ *
+ * Unlike read_seqcount_begin(), this function will not wait for the count
+ * to stabilize. If a writer is active when we begin, we will fail the
+ * read_seqcount_retry() instead of stabilizing at the beginning of the
+ * critical section.
+ */
+static inline unsigned raw_seqcount_begin(const seqcount_t *s)
+{
+	unsigned ret = ACCESS_ONCE(s->sequence);
+	smp_rmb();
+	return ret & ~1;
+}
+
+/**
  * __read_seqcount_retry - end a seq-read critical section (without barrier)
  * @s: pointer to seqcount_t
  * @start: count, from read_seqcount_begin