| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20240503005023.174597-3-21cnbao@gmail.com>
Date: Fri, 3 May 2024 12:50:19 +1200
From: Barry Song <21cnbao@...il.com>
To: akpm@...ux-foundation.org,
linux-mm@...ck.org
Cc: baolin.wang@...ux.alibaba.com,
chrisl@...nel.org,
david@...hat.com,
hanchuanhua@...o.com,
hannes@...xchg.org,
hughd@...gle.com,
kasong@...cent.com,
linux-kernel@...r.kernel.org,
ryan.roberts@....com,
surenb@...gle.com,
v-songbaohua@...o.com,
willy@...radead.org,
xiang@...nel.org,
ying.huang@...el.com,
yosryahmed@...gle.com,
yuzhao@...gle.com,
ziy@...dia.com,
"Rafael J. Wysocki" <rafael@...nel.org>,
Pavel Machek <pavel@....cz>,
Len Brown <len.brown@...el.com>
Subject: [PATCH v3 2/6] mm: remove swap_free() and always use swap_free_nr()
From: Barry Song <v-songbaohua@...o.com>
To streamline maintenance efforts, we propose discontinuing the use of
swap_free(). Instead, we can simply invoke swap_free_nr() with nr set
to 1. This adjustment offers the advantage of enabling batch processing
within kernel/power/swap.c. Furthermore, swap_free_nr() is designed with
a bitmap consisting of only one long, resulting in overhead that can be
ignored for cases where nr equals 1.
Suggested-by: "Huang, Ying" <ying.huang@...el.com>
Signed-off-by: Barry Song <v-songbaohua@...o.com>
Cc: "Rafael J. Wysocki" <rafael@...nel.org>
Cc: Pavel Machek <pavel@....cz>
Cc: Len Brown <len.brown@...el.com>
Cc: Hugh Dickins <hughd@...gle.com>
---
include/linux/swap.h | 5 -----
kernel/power/swap.c | 7 +++----
mm/memory.c | 2 +-
mm/rmap.c | 4 ++--
mm/shmem.c | 4 ++--
mm/swapfile.c | 19 +++++--------------
6 files changed, 13 insertions(+), 28 deletions(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index d1d35e92d7e9..f03cb446124e 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -482,7 +482,6 @@ extern int add_swap_count_continuation(swp_entry_t, gfp_t);
extern void swap_shmem_alloc(swp_entry_t);
extern int swap_duplicate(swp_entry_t);
extern int swapcache_prepare(swp_entry_t);
-extern void swap_free(swp_entry_t);
extern void swap_free_nr(swp_entry_t entry, int nr_pages);
extern void swapcache_free_entries(swp_entry_t *entries, int n);
extern void free_swap_and_cache_nr(swp_entry_t entry, int nr);
@@ -561,10 +560,6 @@ static inline int swapcache_prepare(swp_entry_t swp)
return 0;
}
-static inline void swap_free(swp_entry_t swp)
-{
-}
-
static inline void swap_free_nr(swp_entry_t entry, int nr_pages)
{
}
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 5bc04bfe2db1..6befaa88a342 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -181,7 +181,7 @@ sector_t alloc_swapdev_block(int swap)
offset = swp_offset(get_swap_page_of_type(swap));
if (offset) {
if (swsusp_extents_insert(offset))
- swap_free(swp_entry(swap, offset));
+ swap_free_nr(swp_entry(swap, offset), 1);
else
return swapdev_block(swap, offset);
}
@@ -200,12 +200,11 @@ void free_all_swap_pages(int swap)
while ((node = swsusp_extents.rb_node)) {
struct swsusp_extent *ext;
- unsigned long offset;
ext = rb_entry(node, struct swsusp_extent, node);
rb_erase(node, &swsusp_extents);
- for (offset = ext->start; offset <= ext->end; offset++)
- swap_free(swp_entry(swap, offset));
+ swap_free_nr(swp_entry(swap, ext->start),
+ ext->end - ext->start + 1);
kfree(ext);
}
diff --git a/mm/memory.c b/mm/memory.c
index eea6e4984eae..f033eb3528ba 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4225,7 +4225,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
* We're already holding a reference on the page but haven't mapped it
* yet.
*/
- swap_free(entry);
+ swap_free_nr(entry, 1);
if (should_try_to_free_swap(folio, vma, vmf->flags))
folio_free_swap(folio);
diff --git a/mm/rmap.c b/mm/rmap.c
index 087a79f1f611..39ec7742acec 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1865,7 +1865,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
goto walk_done_err;
}
if (arch_unmap_one(mm, vma, address, pteval) < 0) {
- swap_free(entry);
+ swap_free_nr(entry, 1);
set_pte_at(mm, address, pvmw.pte, pteval);
goto walk_done_err;
}
@@ -1873,7 +1873,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
/* See folio_try_share_anon_rmap(): clear PTE first. */
if (anon_exclusive &&
folio_try_share_anon_rmap_pte(folio, subpage)) {
- swap_free(entry);
+ swap_free_nr(entry, 1);
set_pte_at(mm, address, pvmw.pte, pteval);
goto walk_done_err;
}
diff --git a/mm/shmem.c b/mm/shmem.c
index fa2a0ed97507..bfc8a2beb24f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1836,7 +1836,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
* in shmem_evict_inode().
*/
shmem_recalc_inode(inode, -1, -1);
- swap_free(swap);
+ swap_free_nr(swap, 1);
}
/*
@@ -1927,7 +1927,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
delete_from_swap_cache(folio);
folio_mark_dirty(folio);
- swap_free(swap);
+ swap_free_nr(swap, 1);
put_swap_device(si);
*foliop = folio;
diff --git a/mm/swapfile.c b/mm/swapfile.c
index ec12f2b9d229..ddcd0f24b9a1 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1343,19 +1343,6 @@ static void swap_entry_free(struct swap_info_struct *p, swp_entry_t entry)
swap_range_free(p, offset, 1);
}
-/*
- * Caller has made sure that the swap device corresponding to entry
- * is still around or has not been recycled.
- */
-void swap_free(swp_entry_t entry)
-{
- struct swap_info_struct *p;
-
- p = _swap_info_get(entry);
- if (p)
- __swap_entry_free(p, entry);
-}
-
static void cluster_swap_free_nr(struct swap_info_struct *sis,
unsigned long offset, int nr_pages)
{
@@ -1385,6 +1372,10 @@ static void cluster_swap_free_nr(struct swap_info_struct *sis,
unlock_cluster_or_swap_info(sis, ci);
}
+/*
+ * Caller has made sure that the swap device corresponding to entry
+ * is still around or has not been recycled.
+ */
void swap_free_nr(swp_entry_t entry, int nr_pages)
{
int nr;
@@ -1930,7 +1921,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
new_pte = pte_mkuffd_wp(new_pte);
setpte:
set_pte_at(vma->vm_mm, addr, pte, new_pte);
- swap_free(entry);
+ swap_free_nr(entry, 1);
out:
if (pte)
pte_unmap_unlock(pte, ptl);
--
2.34.1
Powered by blists - more mailing lists