mm: swap: add comment for swap_vma_readahead (e9f59873) · Commits · 戴 / test

mm/swap_state.c

+15 −1

Original line number	Original line	Diff line number	Diff line
	@@ -523,7 +523,7 @@ static unsigned long swapin_nr_pages(unsigned long offset)
	* This has been extended to use the NUMA policies from the mm triggering		* This has been extended to use the NUMA policies from the mm triggering
	* the readahead.		* the readahead.
	*		*
	* Caller must hold down_read on the vma->vm_mm if vmf->vma is not NULL.		* Caller must hold read mmap_sem if vmf->vma is not NULL.
	*/		*/
	struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,		struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
	struct vm_fault *vmf)		struct vm_fault *vmf)
	@@ -698,6 +698,20 @@ static void swap_ra_info(struct vm_fault *vmf,
	pte_unmap(orig_pte);		pte_unmap(orig_pte);
	}		}

			/**
			* swap_vma_readahead - swap in pages in hope we need them soon
			* @entry: swap entry of this memory
			* @gfp_mask: memory allocation flags
			* @vmf: fault information
			*
			* Returns the struct page for entry and addr, after queueing swapin.
			*
			* Primitive swap readahead code. We simply read in a few pages whoes
			* virtual addresses are around the fault address in the same vma.
			*
			* Caller must hold read mmap_sem if vmf->vma is not NULL.
			*
			*/
	static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,		static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
	struct vm_fault *vmf)		struct vm_fault *vmf)
	{		{