Merge tag 'v4.17-rc4' into patchwork

Linux 4.17-rc4

* tag 'v4.17-rc4': (920 commits)
  Linux 4.17-rc4
  KVM: x86: remove APIC Timer periodic/oneshot spikes
  genksyms: fix typo in parse.tab.{c,h} generation rules
  kbuild: replace hardcoded bison in cmd_bison_h with $(YACC)
  gcc-plugins: fix build condition of SANCOV plugin
  MAINTAINERS: Update Kbuild entry with a few paths
  Revert "usb: host: ehci: Use dma_pool_zalloc()"
  platform/x86: Kconfig: Fix dell-laptop dependency chain.
  platform/x86: asus-wireless: Fix NULL pointer dereference
  arm64: vgic-v2: Fix proxying of cpuif access
  KVM: arm/arm64: vgic_init: Cleanup reference to process_maintenance
  KVM: arm64: Fix order of vcpu_write_sys_reg() arguments
  MAINTAINERS & files: Canonize the e-mails I use at files
  media: imx-media-csi: Fix inconsistent IS_ERR and PTR_ERR
  tools: power/acpi, revert to LD = gcc
  bdi: Fix oops in wb_workfn()
  RDMA/cma: Do not query GID during QP state transition to RTR
  IB/mlx4: Fix integer overflow when calculating optimal MTT size
  IB/hfi1: Fix memory leak in exception path in get_irq_affinity()
  IB/{hfi1, rdmavt}: Fix memory leak in hfi1_alloc_devdata() upon failure
  ...

1 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/wait_bit.h b/include/linux/wait_bit.h
index 9318b2166439..2b0072fa5e92 100644
--- a/include/linux/wait_bit.h
+++ b/include/linux/wait_bit.h
@@ -305,4 +305,21 @@ do {									\
 	__ret;								\
 })
 
+/**
+ * clear_and_wake_up_bit - clear a bit and wake up anyone waiting on that bit
+ *
+ * @bit: the bit of the word being waited on
+ * @word: the word being waited on, a kernel virtual address
+ *
+ * You can use this helper if bitflags are manipulated atomically rather than
+ * non-atomically under a lock.
+ */
+static inline void clear_and_wake_up_bit(int bit, void *word)
+{
+	clear_bit_unlock(bit, word);
+	/* See wake_up_bit() for which memory barrier you need to use. */
+	smp_mb__after_atomic();
+	wake_up_bit(word, bit);
+}
+
 #endif /* _LINUX_WAIT_BIT_H */