Re: [PATCH v2 11/61] mm: Remove rb tree.

[David Hildenbrand]

On 17.08.21 17:47, Liam Howlett wrote:
> From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
>
> 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 <Liam.Howlett@xxxxxxxxxx>


[...]


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.

>   	/*
> @@ -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) */
>   
> +

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


--
Thanks,

David / dhildenb