Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:

 - a few random little subsystems

 - almost all of the MM patches which are staged ahead of linux-next
   material. I'll trickle to post-linux-next work in as the dependents
   get merged up.

Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits)
  mm: cleanup kstrto*() usage
  mm: fix fall-through warnings for Clang
  mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
  mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
  mm:backing-dev: use sysfs_emit in macro defining functions
  mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
  mm: use sysfs_emit for struct kobject * uses
  mm: fix kernel-doc markups
  zram: break the strict dependency from lzo
  zram: add stat to gather incompressible pages since zram set up
  zram: support page writeback
  mm/process_vm_access: remove redundant initialization of iov_r
  mm/zsmalloc.c: rework the list_add code in insert_zspage()
  mm/zswap: move to use crypto_acomp API for hardware acceleration
  mm/zswap: fix passing zero to 'PTR_ERR' warning
  mm/zswap: make struct kernel_param_ops definitions const
  userfaultfd/selftests: hint the test runner on required privilege
  userfaultfd/selftests: fix retval check for userfaultfd_open()
  userfaultfd/selftests: always dump something in modes
  userfaultfd: selftests: make __{s,u}64 format specifiers portable
  ...

1 files changed, 89 insertions, 5 deletions

diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h
index 18e7eae9b5ba..0540f0156f58 100644
--- a/include/linux/mmap_lock.h
+++ b/include/linux/mmap_lock.h
@@ -1,11 +1,65 @@
 #ifndef _LINUX_MMAP_LOCK_H
 #define _LINUX_MMAP_LOCK_H
 
+#include <linux/lockdep.h>
+#include <linux/mm_types.h>
 #include <linux/mmdebug.h>
+#include <linux/rwsem.h>
+#include <linux/tracepoint-defs.h>
+#include <linux/types.h>
 
 #define MMAP_LOCK_INITIALIZER(name) \
 	.mmap_lock = __RWSEM_INITIALIZER((name).mmap_lock),
 
+DECLARE_TRACEPOINT(mmap_lock_start_locking);
+DECLARE_TRACEPOINT(mmap_lock_acquire_returned);
+DECLARE_TRACEPOINT(mmap_lock_released);
+
+#ifdef CONFIG_TRACING
+
+void __mmap_lock_do_trace_start_locking(struct mm_struct *mm, bool write);
+void __mmap_lock_do_trace_acquire_returned(struct mm_struct *mm, bool write,
+					   bool success);
+void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write);
+
+static inline void __mmap_lock_trace_start_locking(struct mm_struct *mm,
+						   bool write)
+{
+	if (tracepoint_enabled(mmap_lock_start_locking))
+		__mmap_lock_do_trace_start_locking(mm, write);
+}
+
+static inline void __mmap_lock_trace_acquire_returned(struct mm_struct *mm,
+						      bool write, bool success)
+{
+	if (tracepoint_enabled(mmap_lock_acquire_returned))
+		__mmap_lock_do_trace_acquire_returned(mm, write, success);
+}
+
+static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
+{
+	if (tracepoint_enabled(mmap_lock_released))
+		__mmap_lock_do_trace_released(mm, write);
+}
+
+#else /* !CONFIG_TRACING */
+
+static inline void __mmap_lock_trace_start_locking(struct mm_struct *mm,
+						   bool write)
+{
+}
+
+static inline void __mmap_lock_trace_acquire_returned(struct mm_struct *mm,
+						      bool write, bool success)
+{
+}
+
+static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
+{
+}
+
+#endif /* CONFIG_TRACING */
+
 static inline void mmap_init_lock(struct mm_struct *mm)
 {
 	init_rwsem(&mm->mmap_lock);
@@ -13,57 +67,86 @@ static inline void mmap_init_lock(struct mm_struct *mm)
 
 static inline void mmap_write_lock(struct mm_struct *mm)
 {
+	__mmap_lock_trace_start_locking(mm, true);
 	down_write(&mm->mmap_lock);
+	__mmap_lock_trace_acquire_returned(mm, true, true);
 }
 
 static inline void mmap_write_lock_nested(struct mm_struct *mm, int subclass)
 {
+	__mmap_lock_trace_start_locking(mm, true);
 	down_write_nested(&mm->mmap_lock, subclass);
+	__mmap_lock_trace_acquire_returned(mm, true, true);
 }
 
 static inline int mmap_write_lock_killable(struct mm_struct *mm)
 {
-	return down_write_killable(&mm->mmap_lock);
+	int ret;
+
+	__mmap_lock_trace_start_locking(mm, true);
+	ret = down_write_killable(&mm->mmap_lock);
+	__mmap_lock_trace_acquire_returned(mm, true, ret == 0);
+	return ret;
 }
 
 static inline bool mmap_write_trylock(struct mm_struct *mm)
 {
-	return down_write_trylock(&mm->mmap_lock) != 0;
+	bool ret;
+
+	__mmap_lock_trace_start_locking(mm, true);
+	ret = down_write_trylock(&mm->mmap_lock) != 0;
+	__mmap_lock_trace_acquire_returned(mm, true, ret);
+	return ret;
 }
 
 static inline void mmap_write_unlock(struct mm_struct *mm)
 {
 	up_write(&mm->mmap_lock);
+	__mmap_lock_trace_released(mm, true);
 }
 
 static inline void mmap_write_downgrade(struct mm_struct *mm)
 {
 	downgrade_write(&mm->mmap_lock);
+	__mmap_lock_trace_acquire_returned(mm, false, true);
 }
 
 static inline void mmap_read_lock(struct mm_struct *mm)
 {
+	__mmap_lock_trace_start_locking(mm, false);
 	down_read(&mm->mmap_lock);
+	__mmap_lock_trace_acquire_returned(mm, false, true);
 }
 
 static inline int mmap_read_lock_killable(struct mm_struct *mm)
 {
-	return down_read_killable(&mm->mmap_lock);
+	int ret;
+
+	__mmap_lock_trace_start_locking(mm, false);
+	ret = down_read_killable(&mm->mmap_lock);
+	__mmap_lock_trace_acquire_returned(mm, false, ret == 0);
+	return ret;
 }
 
 static inline bool mmap_read_trylock(struct mm_struct *mm)
 {
-	return down_read_trylock(&mm->mmap_lock) != 0;
+	bool ret;
+
+	__mmap_lock_trace_start_locking(mm, false);
+	ret = down_read_trylock(&mm->mmap_lock) != 0;
+	__mmap_lock_trace_acquire_returned(mm, false, ret);
+	return ret;
 }
 
 static inline void mmap_read_unlock(struct mm_struct *mm)
 {
 	up_read(&mm->mmap_lock);
+	__mmap_lock_trace_released(mm, false);
 }
 
 static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm)
 {
-	if (down_read_trylock(&mm->mmap_lock)) {
+	if (mmap_read_trylock(mm)) {
 		rwsem_release(&mm->mmap_lock.dep_map, _RET_IP_);
 		return true;
 	}
@@ -73,6 +156,7 @@ static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm)
 static inline void mmap_read_unlock_non_owner(struct mm_struct *mm)
 {
 	up_read_non_owner(&mm->mmap_lock);
+	__mmap_lock_trace_released(mm, false);
 }
 
 static inline void mmap_assert_locked(struct mm_struct *mm)