Commit b734b9d9 authored by Lorenzo Stoakes's avatar Lorenzo Stoakes Committed by Andrew Morton
Browse files

mm/vma: small VMA lock cleanups 

We declare vma_start_read() as a static function in mm/mmap_lock.c, so
there is no need to provide a stub for !CONFIG_PER_VMA_LOCK.

__is_vma_write_locked() is declared in a header and should therefore be
static inline.

Put parens around (refcnt & VMA_LOCK_OFFSET) in is_vma_writer_only() to
make precedence clear.

Link: https://lkml.kernel.org/r/20251024090902.1118174-1-lorenzo.stoakes@oracle.com


Signed-off-by: default avatarLorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: default avatarSuren Baghdasaryan <surenb@google.com>
Reviewed-by: default avatarShakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: default avatarVlastimil Babka <vbabka@suse.cz>
Cc: Liam Howlett <liam.howlett@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent ad8b2e09

include/linux/mmap_lock.h

+2 −5
Original line number Diff line number Diff line
@@ -130,7 +130,7 @@ static inline bool is_vma_writer_only(int refcnt) 
	 * a detached vma happens only in vma_mark_detached() and is a rare

	 * case, therefore most of the time there will be no unnecessary wakeup.

	 */

	return refcnt & VMA_LOCK_OFFSET && refcnt <= VMA_LOCK_OFFSET + 1;

	return (refcnt & VMA_LOCK_OFFSET) && refcnt <= VMA_LOCK_OFFSET + 1;

}



static inline void vma_refcount_put(struct vm_area_struct *vma)
@@ -183,7 +183,7 @@ static inline void vma_end_read(struct vm_area_struct *vma) 
}



/* WARNING! Can only be used if mmap_lock is expected to be write-locked */

static bool __is_vma_write_locked(struct vm_area_struct *vma, unsigned int *mm_lock_seq)

static inline bool __is_vma_write_locked(struct vm_area_struct *vma, unsigned int *mm_lock_seq)

{

	mmap_assert_write_locked(vma->vm_mm);
@@ -281,9 +281,6 @@ static inline bool mmap_lock_speculate_retry(struct mm_struct *mm, unsigned int 
	return true;

}

static inline void vma_lock_init(struct vm_area_struct *vma, bool reset_refcnt) {}

static inline struct vm_area_struct *vma_start_read(struct mm_struct *mm,

						    struct vm_area_struct *vma)

		{ return NULL; }

static inline void vma_end_read(struct vm_area_struct *vma) {}

static inline void vma_start_write(struct vm_area_struct *vma) {}

static inline void vma_assert_write_locked(struct vm_area_struct *vma)