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authorJames Morris <jmorris@namei.org>2011-01-10 09:46:24 +1100
committerJames Morris <jmorris@namei.org>2011-01-10 09:46:24 +1100
commitd2e7ad19229f982fc1eb731827d82ceac90abfb3 (patch)
tree98a3741b4d4b27a48b3c7ea9babe331e539416a8 /lib
parentd03a5d888fb688c832d470b749acc5ed38e0bc1d (diff)
parent0c21e3aaf6ae85bee804a325aa29c325209180fd (diff)
downloadlinux-d2e7ad19229f982fc1eb731827d82ceac90abfb3.tar.gz
Merge branch 'master' into next
Conflicts:
	security/smack/smack_lsm.c

Verified and added fix by Stephen Rothwell <sfr@canb.auug.org.au>
Ok'd by Casey Schaufler <casey@schaufler-ca.com>

Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig3
-rw-r--r--lib/Kconfig.debug3
-rw-r--r--lib/Makefile4
-rw-r--r--lib/average.c61
-rw-r--r--lib/debug_locks.c2
-rw-r--r--lib/nlattr.c22
-rw-r--r--lib/percpu_counter.c8
-rw-r--r--lib/timerqueue.c107
8 files changed, 190 insertions, 20 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index fa9bf2c06199..3116aa631af6 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -210,4 +210,7 @@ config GENERIC_ATOMIC64
 config LRU_CACHE
 	tristate
 
+config AVERAGE
+	bool
+
 endmenu
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 28b42b9274d0..2d05adb98401 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -173,7 +173,8 @@ config LOCKUP_DETECTOR
 	  An NMI is generated every 60 seconds or so to check for hardlockups.
 
 config HARDLOCKUP_DETECTOR
-	def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI
+	def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI && \
+		 !ARCH_HAS_NMI_WATCHDOG
 
 config BOOTPARAM_SOFTLOCKUP_PANIC
 	bool "Panic (Reboot) On Soft Lockups"
diff --git a/lib/Makefile b/lib/Makefile
index e6a3763b8212..d7b6e30a3a1e 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -8,7 +8,7 @@ KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
 endif
 
 lib-y := ctype.o string.o vsprintf.o cmdline.o \
-	 rbtree.o radix-tree.o dump_stack.o \
+	 rbtree.o radix-tree.o dump_stack.o timerqueue.o\
 	 idr.o int_sqrt.o extable.o prio_tree.o \
 	 sha1.o irq_regs.o reciprocal_div.o argv_split.o \
 	 proportions.o prio_heap.o ratelimit.o show_mem.o \
@@ -106,6 +106,8 @@ obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o
 
 obj-$(CONFIG_ATOMIC64_SELFTEST) += atomic64_test.o
 
+obj-$(CONFIG_AVERAGE) += average.o
+
 hostprogs-y	:= gen_crc32table
 clean-files	:= crc32table.h
 
diff --git a/lib/average.c b/lib/average.c
new file mode 100644
index 000000000000..5576c2841496
--- /dev/null
+++ b/lib/average.c
@@ -0,0 +1,61 @@
+/*
+ * lib/average.c
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/average.h>
+#include <linux/bug.h>
+#include <linux/log2.h>
+
+/**
+ * DOC: Exponentially Weighted Moving Average (EWMA)
+ *
+ * These are generic functions for calculating Exponentially Weighted Moving
+ * Averages (EWMA). We keep a structure with the EWMA parameters and a scaled
+ * up internal representation of the average value to prevent rounding errors.
+ * The factor for scaling up and the exponential weight (or decay rate) have to
+ * be specified thru the init fuction. The structure should not be accessed
+ * directly but only thru the helper functions.
+ */
+
+/**
+ * ewma_init() - Initialize EWMA parameters
+ * @avg: Average structure
+ * @factor: Factor to use for the scaled up internal value. The maximum value
+ *	of averages can be ULONG_MAX/(factor*weight). For performance reasons
+ *	factor has to be a power of 2.
+ * @weight: Exponential weight, or decay rate. This defines how fast the
+ *	influence of older values decreases. For performance reasons weight has
+ *	to be a power of 2.
+ *
+ * Initialize the EWMA parameters for a given struct ewma @avg.
+ */
+void ewma_init(struct ewma *avg, unsigned long factor, unsigned long weight)
+{
+	WARN_ON(!is_power_of_2(weight) || !is_power_of_2(factor));
+
+	avg->weight = ilog2(weight);
+	avg->factor = ilog2(factor);
+	avg->internal = 0;
+}
+EXPORT_SYMBOL(ewma_init);
+
+/**
+ * ewma_add() - Exponentially weighted moving average (EWMA)
+ * @avg: Average structure
+ * @val: Current value
+ *
+ * Add a sample to the average.
+ */
+struct ewma *ewma_add(struct ewma *avg, unsigned long val)
+{
+	avg->internal = avg->internal  ?
+		(((avg->internal << avg->weight) - avg->internal) +
+			(val << avg->factor)) >> avg->weight :
+		(val << avg->factor);
+	return avg;
+}
+EXPORT_SYMBOL(ewma_add);
diff --git a/lib/debug_locks.c b/lib/debug_locks.c
index 5bf0020b9248..b1c177307677 100644
--- a/lib/debug_locks.c
+++ b/lib/debug_locks.c
@@ -8,7 +8,6 @@
  *
  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
  */
-#include <linux/kernel.h>
 #include <linux/rwsem.h>
 #include <linux/mutex.h>
 #include <linux/module.h>
@@ -39,7 +38,6 @@ int debug_locks_off(void)
 {
 	if (__debug_locks_off()) {
 		if (!debug_locks_silent) {
-			oops_in_progress = 1;
 			console_verbose();
 			return 1;
 		}
diff --git a/lib/nlattr.c b/lib/nlattr.c
index c4706eb98d3d..00e8a02681a6 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -15,7 +15,7 @@
 #include <linux/types.h>
 #include <net/netlink.h>
 
-static u16 nla_attr_minlen[NLA_TYPE_MAX+1] __read_mostly = {
+static const u16 nla_attr_minlen[NLA_TYPE_MAX+1] = {
 	[NLA_U8]	= sizeof(u8),
 	[NLA_U16]	= sizeof(u16),
 	[NLA_U32]	= sizeof(u32),
@@ -23,7 +23,7 @@ static u16 nla_attr_minlen[NLA_TYPE_MAX+1] __read_mostly = {
 	[NLA_NESTED]	= NLA_HDRLEN,
 };
 
-static int validate_nla(struct nlattr *nla, int maxtype,
+static int validate_nla(const struct nlattr *nla, int maxtype,
 			const struct nla_policy *policy)
 {
 	const struct nla_policy *pt;
@@ -115,10 +115,10 @@ static int validate_nla(struct nlattr *nla, int maxtype,
  *
  * Returns 0 on success or a negative error code.
  */
-int nla_validate(struct nlattr *head, int len, int maxtype,
+int nla_validate(const struct nlattr *head, int len, int maxtype,
 		 const struct nla_policy *policy)
 {
-	struct nlattr *nla;
+	const struct nlattr *nla;
 	int rem, err;
 
 	nla_for_each_attr(nla, head, len, rem) {
@@ -173,10 +173,10 @@ nla_policy_len(const struct nla_policy *p, int n)
  *
  * Returns 0 on success or a negative error code.
  */
-int nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head, int len,
-	      const struct nla_policy *policy)
+int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
+	      int len, const struct nla_policy *policy)
 {
-	struct nlattr *nla;
+	const struct nlattr *nla;
 	int rem, err;
 
 	memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1));
@@ -191,7 +191,7 @@ int nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head, int len,
 					goto errout;
 			}
 
-			tb[type] = nla;
+			tb[type] = (struct nlattr *)nla;
 		}
 	}
 
@@ -212,14 +212,14 @@ errout:
  *
  * Returns the first attribute in the stream matching the specified type.
  */
-struct nlattr *nla_find(struct nlattr *head, int len, int attrtype)
+struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype)
 {
-	struct nlattr *nla;
+	const struct nlattr *nla;
 	int rem;
 
 	nla_for_each_attr(nla, head, len, rem)
 		if (nla_type(nla) == attrtype)
-			return nla;
+			return (struct nlattr *)nla;
 
 	return NULL;
 }
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index 604678d7d06d..28f2c33c6b53 100644
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -72,18 +72,16 @@ EXPORT_SYMBOL(percpu_counter_set);
 void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch)
 {
 	s64 count;
-	s32 *pcount;
 
 	preempt_disable();
-	pcount = this_cpu_ptr(fbc->counters);
-	count = *pcount + amount;
+	count = __this_cpu_read(*fbc->counters) + amount;
 	if (count >= batch || count <= -batch) {
 		spin_lock(&fbc->lock);
 		fbc->count += count;
-		*pcount = 0;
+		__this_cpu_write(*fbc->counters, 0);
 		spin_unlock(&fbc->lock);
 	} else {
-		*pcount = count;
+		__this_cpu_write(*fbc->counters, count);
 	}
 	preempt_enable();
 }
diff --git a/lib/timerqueue.c b/lib/timerqueue.c
new file mode 100644
index 000000000000..e3a1050e6820
--- /dev/null
+++ b/lib/timerqueue.c
@@ -0,0 +1,107 @@
+/*
+ *  Generic Timer-queue
+ *
+ *  Manages a simple queue of timers, ordered by expiration time.
+ *  Uses rbtrees for quick list adds and expiration.
+ *
+ *  NOTE: All of the following functions need to be serialized
+ *  to avoid races. No locking is done by this libary code.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/timerqueue.h>
+#include <linux/rbtree.h>
+#include <linux/module.h>
+
+/**
+ * timerqueue_add - Adds timer to timerqueue.
+ *
+ * @head: head of timerqueue
+ * @node: timer node to be added
+ *
+ * Adds the timer node to the timerqueue, sorted by the
+ * node's expires value.
+ */
+void timerqueue_add(struct timerqueue_head *head, struct timerqueue_node *node)
+{
+	struct rb_node **p = &head->head.rb_node;
+	struct rb_node *parent = NULL;
+	struct timerqueue_node  *ptr;
+
+	/* Make sure we don't add nodes that are already added */
+	WARN_ON_ONCE(!RB_EMPTY_NODE(&node->node));
+
+	while (*p) {
+		parent = *p;
+		ptr = rb_entry(parent, struct timerqueue_node, node);
+		if (node->expires.tv64 < ptr->expires.tv64)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+	rb_link_node(&node->node, parent, p);
+	rb_insert_color(&node->node, &head->head);
+
+	if (!head->next || node->expires.tv64 < head->next->expires.tv64)
+		head->next = node;
+}
+EXPORT_SYMBOL_GPL(timerqueue_add);
+
+/**
+ * timerqueue_del - Removes a timer from the timerqueue.
+ *
+ * @head: head of timerqueue
+ * @node: timer node to be removed
+ *
+ * Removes the timer node from the timerqueue.
+ */
+void timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node)
+{
+	WARN_ON_ONCE(RB_EMPTY_NODE(&node->node));
+
+	/* update next pointer */
+	if (head->next == node) {
+		struct rb_node *rbn = rb_next(&node->node);
+
+		head->next = rbn ?
+			rb_entry(rbn, struct timerqueue_node, node) : NULL;
+	}
+	rb_erase(&node->node, &head->head);
+	RB_CLEAR_NODE(&node->node);
+}
+EXPORT_SYMBOL_GPL(timerqueue_del);
+
+/**
+ * timerqueue_iterate_next - Returns the timer after the provided timer
+ *
+ * @node: Pointer to a timer.
+ *
+ * Provides the timer that is after the given node. This is used, when
+ * necessary, to iterate through the list of timers in a timer list
+ * without modifying the list.
+ */
+struct timerqueue_node *timerqueue_iterate_next(struct timerqueue_node *node)
+{
+	struct rb_node *next;
+
+	if (!node)
+		return NULL;
+	next = rb_next(&node->node);
+	if (!next)
+		return NULL;
+	return container_of(next, struct timerqueue_node, node);
+}
+EXPORT_SYMBOL_GPL(timerqueue_iterate_next);