* David Hildenbrand [off-list ref] [210823 05:49]:

On 17.08.21 17:47, Liam Howlett wrote:

quoted

From: "Liam R. Howlett" <redacted>

Remove the RB tree and start using the maple tree for vm_area_struct
tracking.

Drop validate_mm() calls in expand_upwards() and expand_downwards() as
the lock is not held.

Signed-off-by: Liam R. Howlett <redacted>

[...]


Why are we reshuffling the code below? This either needs a good
justification or should just be dropped as it introduces noise. Maybe I am
missing something important.

quoted

  	/*

@@ -427,6 +414,11 @@ struct vm_area_struct {
  	pgprot_t vm_page_prot;
  	unsigned long vm_flags;		/* Flags, see mm.h. */
+	/* Information about our backing store: */
+	unsigned long vm_pgoff;		/* Offset (within vm_file) in PAGE_SIZE
+					 * units
+					 */
+	struct file *vm_file;		/* File we map to (can be NULL). */
  	/*
  	 * For areas with an address space and backing store,
  	 * linkage into the address_space->i_mmap interval tree.

@@ -449,12 +441,9 @@ struct vm_area_struct {
  	/* Function pointers to deal with this struct. */
  	const struct vm_operations_struct *vm_ops;
-	/* Information about our backing store: */
-	unsigned long vm_pgoff;		/* Offset (within vm_file) in PAGE_SIZE
-					   units */
-	struct file * vm_file;		/* File we map to (can be NULL). */
  	void * vm_private_data;		/* was vm_pte (shared mem) */
+

Thank you, I will drop this from the next revision.

Another unrelated change (there seem to some more in this patch)

I'll have a look though it again.

Thanks,
Liam