summaryrefslogtreecommitdiffstats
path: root/lib
diff options
context:
space:
mode:
Diffstat (limited to 'lib')
-rw-r--r--lib/Makefile2
-rw-r--r--lib/average.c6
-rw-r--r--lib/flex_array.c7
-rw-r--r--lib/hash.c39
-rw-r--r--lib/kobject_uevent.c10
-rw-r--r--lib/reciprocal_div.c24
6 files changed, 78 insertions, 10 deletions
diff --git a/lib/Makefile b/lib/Makefile
index 98ec3b8..126b34f 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -26,7 +26,7 @@ obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
gcd.o lcm.o list_sort.o uuid.o flex_array.o iovec.o clz_ctz.o \
bsearch.o find_last_bit.o find_next_bit.o llist.o memweight.o kfifo.o \
- percpu-refcount.o percpu_ida.o
+ percpu-refcount.o percpu_ida.o hash.o
obj-y += string_helpers.o
obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
obj-y += kstrtox.o
diff --git a/lib/average.c b/lib/average.c
index 99a67e6..114d1be 100644
--- a/lib/average.c
+++ b/lib/average.c
@@ -53,8 +53,10 @@ EXPORT_SYMBOL(ewma_init);
*/
struct ewma *ewma_add(struct ewma *avg, unsigned long val)
{
- avg->internal = avg->internal ?
- (((avg->internal << avg->weight) - avg->internal) +
+ unsigned long internal = ACCESS_ONCE(avg->internal);
+
+ ACCESS_ONCE(avg->internal) = internal ?
+ (((internal << avg->weight) - internal) +
(val << avg->factor)) >> avg->weight :
(val << avg->factor);
return avg;
diff --git a/lib/flex_array.c b/lib/flex_array.c
index 6948a66..2eed22f 100644
--- a/lib/flex_array.c
+++ b/lib/flex_array.c
@@ -90,8 +90,8 @@ struct flex_array *flex_array_alloc(int element_size, unsigned int total,
{
struct flex_array *ret;
int elems_per_part = 0;
- int reciprocal_elems = 0;
int max_size = 0;
+ struct reciprocal_value reciprocal_elems = { 0 };
if (element_size) {
elems_per_part = FLEX_ARRAY_ELEMENTS_PER_PART(element_size);
@@ -119,6 +119,11 @@ EXPORT_SYMBOL(flex_array_alloc);
static int fa_element_to_part_nr(struct flex_array *fa,
unsigned int element_nr)
{
+ /*
+ * if element_size == 0 we don't get here, so we never touch
+ * the zeroed fa->reciprocal_elems, which would yield invalid
+ * results
+ */
return reciprocal_divide(element_nr, fa->reciprocal_elems);
}
diff --git a/lib/hash.c b/lib/hash.c
new file mode 100644
index 0000000..fea973f
--- /dev/null
+++ b/lib/hash.c
@@ -0,0 +1,39 @@
+/* General purpose hashing library
+ *
+ * That's a start of a kernel hashing library, which can be extended
+ * with further algorithms in future. arch_fast_hash{2,}() will
+ * eventually resolve to an architecture optimized implementation.
+ *
+ * Copyright 2013 Francesco Fusco <ffusco@redhat.com>
+ * Copyright 2013 Daniel Borkmann <dborkman@redhat.com>
+ * Copyright 2013 Thomas Graf <tgraf@redhat.com>
+ * Licensed under the GNU General Public License, version 2.0 (GPLv2)
+ */
+
+#include <linux/jhash.h>
+#include <linux/hash.h>
+#include <linux/cache.h>
+
+static struct fast_hash_ops arch_hash_ops __read_mostly = {
+ .hash = jhash,
+ .hash2 = jhash2,
+};
+
+u32 arch_fast_hash(const void *data, u32 len, u32 seed)
+{
+ return arch_hash_ops.hash(data, len, seed);
+}
+EXPORT_SYMBOL_GPL(arch_fast_hash);
+
+u32 arch_fast_hash2(const u32 *data, u32 len, u32 seed)
+{
+ return arch_hash_ops.hash2(data, len, seed);
+}
+EXPORT_SYMBOL_GPL(arch_fast_hash2);
+
+static int __init hashlib_init(void)
+{
+ setup_arch_fast_hash(&arch_hash_ops);
+ return 0;
+}
+early_initcall(hashlib_init);
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index 52e5abb..5f72767 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -88,11 +88,17 @@ out:
#ifdef CONFIG_NET
static int kobj_bcast_filter(struct sock *dsk, struct sk_buff *skb, void *data)
{
- struct kobject *kobj = data;
+ struct kobject *kobj = data, *ksobj;
const struct kobj_ns_type_operations *ops;
ops = kobj_ns_ops(kobj);
- if (ops) {
+ if (!ops && kobj->kset) {
+ ksobj = &kobj->kset->kobj;
+ if (ksobj->parent != NULL)
+ ops = kobj_ns_ops(ksobj->parent);
+ }
+
+ if (ops && ops->netlink_ns && kobj->ktype->namespace) {
const void *sock_ns, *ns;
ns = kobj->ktype->namespace(kobj);
sock_ns = ops->netlink_ns(dsk);
diff --git a/lib/reciprocal_div.c b/lib/reciprocal_div.c
index 75510e9..4641524 100644
--- a/lib/reciprocal_div.c
+++ b/lib/reciprocal_div.c
@@ -1,11 +1,27 @@
+#include <linux/kernel.h>
#include <asm/div64.h>
#include <linux/reciprocal_div.h>
#include <linux/export.h>
-u32 reciprocal_value(u32 k)
+/*
+ * For a description of the algorithm please have a look at
+ * include/linux/reciprocal_div.h
+ */
+
+struct reciprocal_value reciprocal_value(u32 d)
{
- u64 val = (1LL << 32) + (k - 1);
- do_div(val, k);
- return (u32)val;
+ struct reciprocal_value R;
+ u64 m;
+ int l;
+
+ l = fls(d - 1);
+ m = ((1ULL << 32) * ((1ULL << l) - d));
+ do_div(m, d);
+ ++m;
+ R.m = (u32)m;
+ R.sh1 = min(l, 1);
+ R.sh2 = max(l - 1, 0);
+
+ return R;
}
EXPORT_SYMBOL(reciprocal_value);
OpenPOWER on IntegriCloud