Merge branch 'linus' into sched/devel

6 files changed, 103 insertions, 8 deletions

diff --git a/include/linux/cnt32_to_63.h b/include/linux/cnt32_to_63.h
new file mode 100644
index 00000000000..8c0f9505b48
--- /dev/null
+++ b/include/linux/cnt32_to_63.h
@@ -0,0 +1,80 @@
+/*
+ *  Extend a 32-bit counter to 63 bits
+ *
+ *  Author:	Nicolas Pitre
+ *  Created:	December 3, 2006
+ *  Copyright:	MontaVista Software, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ */
+
+#ifndef __LINUX_CNT32_TO_63_H__
+#define __LINUX_CNT32_TO_63_H__
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/byteorder.h>
+
+/* this is used only to give gcc a clue about good code generation */
+union cnt32_to_63 {
+	struct {
+#if defined(__LITTLE_ENDIAN)
+		u32 lo, hi;
+#elif defined(__BIG_ENDIAN)
+		u32 hi, lo;
+#endif
+	};
+	u64 val;
+};
+
+
+/**
+ * cnt32_to_63 - Expand a 32-bit counter to a 63-bit counter
+ * @cnt_lo: The low part of the counter
+ *
+ * Many hardware clock counters are only 32 bits wide and therefore have
+ * a relatively short period making wrap-arounds rather frequent.  This
+ * is a problem when implementing sched_clock() for example, where a 64-bit
+ * non-wrapping monotonic value is expected to be returned.
+ *
+ * To overcome that limitation, let's extend a 32-bit counter to 63 bits
+ * in a completely lock free fashion. Bits 0 to 31 of the clock are provided
+ * by the hardware while bits 32 to 62 are stored in memory.  The top bit in
+ * memory is used to synchronize with the hardware clock half-period.  When
+ * the top bit of both counters (hardware and in memory) differ then the
+ * memory is updated with a new value, incrementing it when the hardware
+ * counter wraps around.
+ *
+ * Because a word store in memory is atomic then the incremented value will
+ * always be in synch with the top bit indicating to any potential concurrent
+ * reader if the value in memory is up to date or not with regards to the
+ * needed increment.  And any race in updating the value in memory is harmless
+ * as the same value would simply be stored more than once.
+ *
+ * The only restriction for the algorithm to work properly is that this
+ * code must be executed at least once per each half period of the 32-bit
+ * counter to properly update the state bit in memory. This is usually not a
+ * problem in practice, but if it is then a kernel timer could be scheduled
+ * to manage for this code to be executed often enough.
+ *
+ * Note that the top bit (bit 63) in the returned value should be considered
+ * as garbage.  It is not cleared here because callers are likely to use a
+ * multiplier on the returned value which can get rid of the top bit
+ * implicitly by making the multiplier even, therefore saving on a runtime
+ * clear-bit instruction. Otherwise caller must remember to clear the top
+ * bit explicitly.
+ */
+#define cnt32_to_63(cnt_lo) \
+({ \
+	static volatile u32 __m_cnt_hi; \
+	union cnt32_to_63 __x; \
+	__x.hi = __m_cnt_hi; \
+	__x.lo = (cnt_lo); \
+	if (unlikely((s32)(__x.hi ^ __x.lo) < 0)) \
+		__m_cnt_hi = __x.hi = (__x.hi ^ 0x80000000) + (__x.hi >> 31); \
+	__x.val; \
+})
+
+#endif
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 6d93dce61cb..2f245fe63bd 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -47,14 +47,22 @@ enum hrtimer_restart {
  *	HRTIMER_CB_IRQSAFE:		Callback may run in hardirq context
  *	HRTIMER_CB_IRQSAFE_NO_RESTART:	Callback may run in hardirq context and
  *					does not restart the timer
- *	HRTIMER_CB_IRQSAFE_NO_SOFTIRQ:	Callback must run in hardirq context
- *					Special mode for tick emultation
+ *	HRTIMER_CB_IRQSAFE_PERCPU:	Callback must run in hardirq context
+ *					Special mode for tick emulation and
+ *					scheduler timer. Such timers are per
+ *					cpu and not allowed to be migrated on
+ *					cpu unplug.
+ *	HRTIMER_CB_IRQSAFE_UNLOCKED:	Callback should run in hardirq context
+ *					with timer->base lock unlocked
+ *					used for timers which call wakeup to
+ *					avoid lock order problems with rq->lock
  */
 enum hrtimer_cb_mode {
 	HRTIMER_CB_SOFTIRQ,
 	HRTIMER_CB_IRQSAFE,
 	HRTIMER_CB_IRQSAFE_NO_RESTART,
-	HRTIMER_CB_IRQSAFE_NO_SOFTIRQ,
+	HRTIMER_CB_IRQSAFE_PERCPU,
+	HRTIMER_CB_IRQSAFE_UNLOCKED,
 };
 
 /*
@@ -67,9 +75,10 @@ enum hrtimer_cb_mode {
  * 0x02		callback function running
  * 0x04		callback pending (high resolution mode)
  *
- * Special case:
+ * Special cases:
  * 0x03		callback function running and enqueued
  *		(was requeued on another CPU)
+ * 0x09		timer was migrated on CPU hotunplug
  * The "callback function running and enqueued" status is only possible on
  * SMP. It happens for example when a posix timer expired and the callback
  * queued a signal. Between dropping the lock which protects the posix timer
@@ -87,6 +96,7 @@ enum hrtimer_cb_mode {
 #define HRTIMER_STATE_ENQUEUED	0x01
 #define HRTIMER_STATE_CALLBACK	0x02
 #define HRTIMER_STATE_PENDING	0x04
+#define HRTIMER_STATE_MIGRATE	0x08
 
 /**
  * struct hrtimer - the basic hrtimer structure
diff --git a/include/linux/pci.h b/include/linux/pci.h
index c0e14008a3c..98dc6243a70 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -534,7 +534,7 @@ extern void pci_sort_breadthfirst(void);
 #ifdef CONFIG_PCI_LEGACY
 struct pci_dev __deprecated *pci_find_device(unsigned int vendor,
 					     unsigned int device,
-					     const struct pci_dev *from);
+					     struct pci_dev *from);
 struct pci_dev __deprecated *pci_find_slot(unsigned int bus,
 					   unsigned int devfn);
 #endif /* CONFIG_PCI_LEGACY */
@@ -550,7 +550,7 @@ struct pci_dev *pci_get_device(unsigned int vendor, unsigned int device,
 				struct pci_dev *from);
 struct pci_dev *pci_get_subsys(unsigned int vendor, unsigned int device,
 				unsigned int ss_vendor, unsigned int ss_device,
-				const struct pci_dev *from);
+				struct pci_dev *from);
 struct pci_dev *pci_get_slot(struct pci_bus *bus, unsigned int devfn);
 struct pci_dev *pci_get_bus_and_slot(unsigned int bus, unsigned int devfn);
 struct pci_dev *pci_get_class(unsigned int class, struct pci_dev *from);
@@ -816,7 +816,7 @@ _PCI_NOP_ALL(write,)
 
 static inline struct pci_dev *pci_find_device(unsigned int vendor,
 					      unsigned int device,
-					      const struct pci_dev *from)
+					      struct pci_dev *from)
 {
 	return NULL;
 }
@@ -838,7 +838,7 @@ static inline struct pci_dev *pci_get_subsys(unsigned int vendor,
 					     unsigned int device,
 					     unsigned int ss_vendor,
 					     unsigned int ss_device,
-					     const struct pci_dev *from)
+					     struct pci_dev *from)
 {
 	return NULL;
 }
diff --git a/include/linux/ramfs.h b/include/linux/ramfs.h
index b160fb18e8d..37aaf2b3986 100644
--- a/include/linux/ramfs.h
+++ b/include/linux/ramfs.h
@@ -6,6 +6,7 @@ extern int ramfs_get_sb(struct file_system_type *fs_type,
 	 int flags, const char *dev_name, void *data, struct vfsmount *mnt);
 
 #ifndef CONFIG_MMU
+extern int ramfs_nommu_expand_for_mapping(struct inode *inode, size_t newsize);
 extern unsigned long ramfs_nommu_get_unmapped_area(struct file *file,
 						   unsigned long addr,
 						   unsigned long len,
diff --git a/include/linux/smb.h b/include/linux/smb.h
index caa43b2370c..82fefddc598 100644
--- a/include/linux/smb.h
+++ b/include/linux/smb.h
@@ -11,7 +11,9 @@
 
 #include <linux/types.h>
 #include <linux/magic.h>
+#ifdef __KERNEL__
 #include <linux/time.h>
+#endif
 
 enum smb_protocol { 
 	SMB_PROTOCOL_NONE, 
diff --git a/include/linux/stacktrace.h b/include/linux/stacktrace.h
index 5da9794b2d7..b106fd8e0d5 100644
--- a/include/linux/stacktrace.h
+++ b/include/linux/stacktrace.h
@@ -1,6 +1,8 @@
 #ifndef __LINUX_STACKTRACE_H
 #define __LINUX_STACKTRACE_H
 
+struct task_struct;
+
 #ifdef CONFIG_STACKTRACE
 struct stack_trace {
 	unsigned int nr_entries, max_entries;