include/linux/nodemask.h: create next_node_in() helper
Lots of code does
node = next_node(node, XXX);
if (node == MAX_NUMNODES)
node = first_node(XXX);
so create next_node_in() to do this and use it in various places.
[mhocko@suse.com: use next_node_in() helper]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Hui Zhu <zhuhui@xiaomi.com>
Cc: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/tile/kernel/setup.c b/arch/tile/kernel/setup.c
index a992238..153020a 100644
--- a/arch/tile/kernel/setup.c
+++ b/arch/tile/kernel/setup.c
@@ -962,9 +962,7 @@
cpumask_set_cpu(best_cpu, &node_2_cpu_mask[node]);
cpu_2_node[best_cpu] = node;
cpumask_clear_cpu(best_cpu, &unbound_cpus);
- node = next_node(node, default_nodes);
- if (node == MAX_NUMNODES)
- node = first_node(default_nodes);
+ node = next_node_in(node, default_nodes);
}
/* Print out node assignments and set defaults for disabled cpus */
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index f70c1ff..9c086c5 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -617,9 +617,7 @@
if (early_cpu_to_node(i) != NUMA_NO_NODE)
continue;
numa_set_node(i, rr);
- rr = next_node(rr, node_online_map);
- if (rr == MAX_NUMNODES)
- rr = first_node(node_online_map);
+ rr = next_node_in(rr, node_online_map);
}
}
diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
index 6e85889..f746e44 100644
--- a/include/linux/nodemask.h
+++ b/include/linux/nodemask.h
@@ -43,8 +43,10 @@
*
* int first_node(mask) Number lowest set bit, or MAX_NUMNODES
* int next_node(node, mask) Next node past 'node', or MAX_NUMNODES
+ * int next_node_in(node, mask) Next node past 'node', or wrap to first,
+ * or MAX_NUMNODES
* int first_unset_node(mask) First node not set in mask, or
- * MAX_NUMNODES.
+ * MAX_NUMNODES
*
* nodemask_t nodemask_of_node(node) Return nodemask with bit 'node' set
* NODE_MASK_ALL Initializer - all bits set
@@ -259,6 +261,13 @@
return min_t(int,MAX_NUMNODES,find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
}
+/*
+ * Find the next present node in src, starting after node n, wrapping around to
+ * the first node in src if needed. Returns MAX_NUMNODES if src is empty.
+ */
+#define next_node_in(n, src) __next_node_in((n), &(src))
+int __next_node_in(int node, const nodemask_t *srcp);
+
static inline void init_nodemask_of_node(nodemask_t *mask, int node)
{
nodes_clear(*mask);
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 1902956..611cc69 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -2591,13 +2591,7 @@
static int cpuset_spread_node(int *rotor)
{
- int node;
-
- node = next_node(*rotor, current->mems_allowed);
- if (node == MAX_NUMNODES)
- node = first_node(current->mems_allowed);
- *rotor = node;
- return node;
+ return *rotor = next_node_in(*rotor, current->mems_allowed);
}
int cpuset_mem_spread_node(void)
diff --git a/lib/Makefile b/lib/Makefile
index 931396a..42b6918 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -25,7 +25,7 @@
sha1.o md5.o irq_regs.o argv_split.o \
flex_proportions.o ratelimit.o show_mem.o \
is_single_threaded.o plist.o decompress.o kobject_uevent.o \
- earlycpio.o seq_buf.o nmi_backtrace.o
+ earlycpio.o seq_buf.o nmi_backtrace.o nodemask.o
obj-$(CONFIG_ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS) += usercopy.o
lib-$(CONFIG_MMU) += ioremap.o
diff --git a/lib/nodemask.c b/lib/nodemask.c
new file mode 100644
index 0000000..e42a5bf4
--- /dev/null
+++ b/lib/nodemask.c
@@ -0,0 +1,30 @@
+#include <linux/nodemask.h>
+#include <linux/module.h>
+#include <linux/random.h>
+
+int __next_node_in(int node, const nodemask_t *srcp)
+{
+ int ret = __next_node(node, srcp);
+
+ if (ret == MAX_NUMNODES)
+ ret = __first_node(srcp);
+ return ret;
+}
+EXPORT_SYMBOL(__next_node_in);
+
+#ifdef CONFIG_NUMA
+/*
+ * Return the bit number of a random bit set in the nodemask.
+ * (returns NUMA_NO_NODE if nodemask is empty)
+ */
+int node_random(const nodemask_t *maskp)
+{
+ int w, bit = NUMA_NO_NODE;
+
+ w = nodes_weight(*maskp);
+ if (w)
+ bit = bitmap_ord_to_pos(maskp->bits,
+ get_random_int() % w, MAX_NUMNODES);
+ return bit;
+}
+#endif
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 19d0d08..5856093 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -937,9 +937,7 @@
*/
static int next_node_allowed(int nid, nodemask_t *nodes_allowed)
{
- nid = next_node(nid, *nodes_allowed);
- if (nid == MAX_NUMNODES)
- nid = first_node(*nodes_allowed);
+ nid = next_node_in(nid, *nodes_allowed);
VM_BUG_ON(nid >= MAX_NUMNODES);
return nid;
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index fe787f5..6740c4c 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1389,9 +1389,7 @@
mem_cgroup_may_update_nodemask(memcg);
node = memcg->last_scanned_node;
- node = next_node(node, memcg->scan_nodes);
- if (node == MAX_NUMNODES)
- node = first_node(memcg->scan_nodes);
+ node = next_node_in(node, memcg->scan_nodes);
/*
* We call this when we hit limit, not when pages are added to LRU.
* No LRU may hold pages because all pages are UNEVICTABLE or
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 36cc01b..8d369ce 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -97,7 +97,6 @@
#include <asm/tlbflush.h>
#include <asm/uaccess.h>
-#include <linux/random.h>
#include "internal.h"
@@ -347,9 +346,7 @@
BUG();
if (!node_isset(current->il_next, tmp)) {
- current->il_next = next_node(current->il_next, tmp);
- if (current->il_next >= MAX_NUMNODES)
- current->il_next = first_node(tmp);
+ current->il_next = next_node_in(current->il_next, tmp);
if (current->il_next >= MAX_NUMNODES)
current->il_next = numa_node_id();
}
@@ -1709,9 +1706,7 @@
struct task_struct *me = current;
nid = me->il_next;
- next = next_node(nid, policy->v.nodes);
- if (next >= MAX_NUMNODES)
- next = first_node(policy->v.nodes);
+ next = next_node_in(nid, policy->v.nodes);
if (next < MAX_NUMNODES)
me->il_next = next;
return nid;
@@ -1805,21 +1800,6 @@
return interleave_nodes(pol);
}
-/*
- * Return the bit number of a random bit set in the nodemask.
- * (returns NUMA_NO_NODE if nodemask is empty)
- */
-int node_random(const nodemask_t *maskp)
-{
- int w, bit = NUMA_NO_NODE;
-
- w = nodes_weight(*maskp);
- if (w)
- bit = bitmap_ord_to_pos(maskp->bits,
- get_random_int() % w, MAX_NUMNODES);
- return bit;
-}
-
#ifdef CONFIG_HUGETLBFS
/*
* huge_zonelist(@vma, @addr, @gfp_flags, @mpol)
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index c4f5682..67bedd1 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -288,13 +288,10 @@
* accordance with memory policy of the user process if possible. For
* now as a simple work-around, we use the next node for destination.
*/
- if (PageHuge(page)) {
- int node = next_online_node(page_to_nid(page));
- if (node == MAX_NUMNODES)
- node = first_online_node;
+ if (PageHuge(page))
return alloc_huge_page_node(page_hstate(compound_head(page)),
- node);
- }
+ next_node_in(page_to_nid(page),
+ node_online_map));
if (PageHighMem(page))
gfp_mask |= __GFP_HIGHMEM;
diff --git a/mm/slab.c b/mm/slab.c
index d81565a..c11bf50 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -522,22 +522,15 @@
static void init_reap_node(int cpu)
{
- int node;
-
- node = next_node(cpu_to_mem(cpu), node_online_map);
- if (node == MAX_NUMNODES)
- node = first_node(node_online_map);
-
- per_cpu(slab_reap_node, cpu) = node;
+ per_cpu(slab_reap_node, cpu) = next_node_in(cpu_to_mem(cpu),
+ node_online_map);
}
static void next_reap_node(void)
{
int node = __this_cpu_read(slab_reap_node);
- node = next_node(node, node_online_map);
- if (unlikely(node >= MAX_NUMNODES))
- node = first_node(node_online_map);
+ node = next_node_in(node, node_online_map);
__this_cpu_write(slab_reap_node, node);
}