Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:
 "191 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
  slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
  mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
  mm,hwpoison: make get_hwpoison_page() call get_any_page()
  mm,hwpoison: send SIGBUS with error virutal address
  mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
  mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
  mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
  mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
  docs: remove description of DISCONTIGMEM
  arch, mm: remove stale mentions of DISCONIGMEM
  mm: remove CONFIG_DISCONTIGMEM
  m68k: remove support for DISCONTIGMEM
  arc: remove support for DISCONTIGMEM
  arc: update comment about HIGHMEM implementation
  alpha: remove DISCONTIGMEM and NUMA
  mm/page_alloc: move free_the_page
  mm/page_alloc: fix counting of managed_pages
  mm/page_alloc: improve memmap_pages dbg msg
  mm: drop SECTION_SHIFT in code comments
  mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
  mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
  mm/page_alloc: scale the number of pages that are batch freed
  ...

1 files changed, 22 insertions, 11 deletions

diff --git a/mm/mmap_lock.c b/mm/mmap_lock.c
index dcdde4f722a4..2ae3f33b85b1 100644
--- a/mm/mmap_lock.c
+++ b/mm/mmap_lock.c
@@ -11,6 +11,7 @@
 #include <linux/rcupdate.h>
 #include <linux/smp.h>
 #include <linux/trace_events.h>
+#include <linux/local_lock.h>
 
 EXPORT_TRACEPOINT_SYMBOL(mmap_lock_start_locking);
 EXPORT_TRACEPOINT_SYMBOL(mmap_lock_acquire_returned);
@@ -39,21 +40,30 @@ static int reg_refcount; /* Protected by reg_lock. */
  */
 #define CONTEXT_COUNT 4
 
-static DEFINE_PER_CPU(char __rcu *, memcg_path_buf);
+struct memcg_path {
+	local_lock_t lock;
+	char __rcu *buf;
+	local_t buf_idx;
+};
+static DEFINE_PER_CPU(struct memcg_path, memcg_paths) = {
+	.lock = INIT_LOCAL_LOCK(lock),
+	.buf_idx = LOCAL_INIT(0),
+};
+
 static char **tmp_bufs;
-static DEFINE_PER_CPU(int, memcg_path_buf_idx);
 
 /* Called with reg_lock held. */
 static void free_memcg_path_bufs(void)
 {
+	struct memcg_path *memcg_path;
 	int cpu;
 	char **old = tmp_bufs;
 
 	for_each_possible_cpu(cpu) {
-		*(old++) = rcu_dereference_protected(
-			per_cpu(memcg_path_buf, cpu),
+		memcg_path = per_cpu_ptr(&memcg_paths, cpu);
+		*(old++) = rcu_dereference_protected(memcg_path->buf,
 			lockdep_is_held(&reg_lock));
-		rcu_assign_pointer(per_cpu(memcg_path_buf, cpu), NULL);
+		rcu_assign_pointer(memcg_path->buf, NULL);
 	}
 
 	/* Wait for inflight memcg_path_buf users to finish. */
@@ -88,7 +98,7 @@ int trace_mmap_lock_reg(void)
 		new = kmalloc(MEMCG_PATH_BUF_SIZE * CONTEXT_COUNT, GFP_KERNEL);
 		if (new == NULL)
 			goto out_fail_free;
-		rcu_assign_pointer(per_cpu(memcg_path_buf, cpu), new);
+		rcu_assign_pointer(per_cpu_ptr(&memcg_paths, cpu)->buf, new);
 		/* Don't need to wait for inflights, they'd have gotten NULL. */
 	}
 
@@ -122,23 +132,24 @@ out:
 
 static inline char *get_memcg_path_buf(void)
 {
+	struct memcg_path *memcg_path = this_cpu_ptr(&memcg_paths);
 	char *buf;
 	int idx;
 
 	rcu_read_lock();
-	buf = rcu_dereference(*this_cpu_ptr(&memcg_path_buf));
+	buf = rcu_dereference(memcg_path->buf);
 	if (buf == NULL) {
 		rcu_read_unlock();
 		return NULL;
 	}
-	idx = this_cpu_add_return(memcg_path_buf_idx, MEMCG_PATH_BUF_SIZE) -
+	idx = local_add_return(MEMCG_PATH_BUF_SIZE, &memcg_path->buf_idx) -
 	      MEMCG_PATH_BUF_SIZE;
 	return &buf[idx];
 }
 
 static inline void put_memcg_path_buf(void)
 {
-	this_cpu_sub(memcg_path_buf_idx, MEMCG_PATH_BUF_SIZE);
+	local_sub(MEMCG_PATH_BUF_SIZE, &this_cpu_ptr(&memcg_paths)->buf_idx);
 	rcu_read_unlock();
 }
 
@@ -179,14 +190,14 @@ out:
 #define TRACE_MMAP_LOCK_EVENT(type, mm, ...)                                   \
 	do {                                                                   \
 		const char *memcg_path;                                        \
-		preempt_disable();                                             \
+		local_lock(&memcg_paths.lock);				       \
 		memcg_path = get_mm_memcg_path(mm);                            \
 		trace_mmap_lock_##type(mm,                                     \
 				       memcg_path != NULL ? memcg_path : "",   \
 				       ##__VA_ARGS__);                         \
 		if (likely(memcg_path != NULL))                                \
 			put_memcg_path_buf();                                  \
-		preempt_enable();                                              \
+		local_unlock(&memcg_paths.lock);			       \
 	} while (0)
 
 #else /* !CONFIG_MEMCG */