Commit 3f641cf9 authored by Kairui Song's avatar Kairui Song Committed by Andrew Morton
Browse files

mm, swap: introduce a helper for retrieving cluster from offset 

It's a common operation to retrieve the cluster info from offset,
introduce a helper for this.

Link: https://lkml.kernel.org/r/20250113175732.48099-12-ryncsn@gmail.com


Signed-off-by: default avatarKairui Song <kasong@tencent.com>
Suggested-by: default avatarChris Li <chrisl@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <v-songbaohua@oppo.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickens <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent e3ae2dec

mm/swapfile.c

+10 −4
Original line number Diff line number Diff line
@@ -424,6 +424,12 @@ static inline unsigned int cluster_index(struct swap_info_struct *si, 
	return ci - si->cluster_info;

}



static inline struct swap_cluster_info *offset_to_cluster(struct swap_info_struct *si,

							  unsigned long offset)

{

	return &si->cluster_info[offset / SWAPFILE_CLUSTER];

}



static inline unsigned int cluster_offset(struct swap_info_struct *si,

					  struct swap_cluster_info *ci)

{
@@ -435,7 +441,7 @@ static inline struct swap_cluster_info *lock_cluster(struct swap_info_struct *si 
{

	struct swap_cluster_info *ci;



	ci = &si->cluster_info[offset / SWAPFILE_CLUSTER];

	ci = offset_to_cluster(si, offset);

	spin_lock(&ci->lock);



	return ci;
@@ -1480,10 +1486,10 @@ static void swap_entry_range_free(struct swap_info_struct *si, swp_entry_t entry 
	unsigned char *map_end = map + nr_pages;

	struct swap_cluster_info *ci;



	/* It should never free entries across different clusters */

	VM_BUG_ON((offset / SWAPFILE_CLUSTER) != ((offset + nr_pages - 1) / SWAPFILE_CLUSTER));



	ci = lock_cluster(si, offset);



	/* It should never free entries across different clusters */

	VM_BUG_ON(ci != offset_to_cluster(si, offset + nr_pages - 1));

	VM_BUG_ON(cluster_is_empty(ci));

	VM_BUG_ON(ci->count < nr_pages);