linux-kernel - [PATCH 06/13] mm: Rename pmd_read

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20221022114424.841277397@infradead.org>
Date:   Sat, 22 Oct 2022 13:14:09 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     x86@...nel.org, willy@...radead.org, torvalds@...ux-foundation.org,
        akpm@...ux-foundation.org
Cc:     linux-kernel@...r.kernel.org, peterz@...radead.org,
        linux-mm@...ck.org, aarcange@...hat.com,
        kirill.shutemov@...ux.intel.com, jroedel@...e.de, ubizjak@...il.com
Subject: [PATCH 06/13] mm: Rename pmd_read_atomic()

There's no point in having the identical routines for PTE/PMD have
different names.

Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
---
 include/linux/pgtable.h    |    9 ++-------
 mm/hmm.c                   |    2 +-
 mm/khugepaged.c            |    2 +-
 mm/mapping_dirty_helpers.c |    2 +-
 mm/mprotect.c              |    2 +-
 mm/userfaultfd.c           |    2 +-
 mm/vmscan.c                |    4 ++--
 7 files changed, 9 insertions(+), 14 deletions(-)

--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1352,11 +1352,6 @@ static inline int pud_trans_unstable(pud
 #endif
 }
 
-static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
-{
-	return pmdp_get_lockless(pmdp);
-}
-
 #ifndef arch_needs_pgtable_deposit
 #define arch_needs_pgtable_deposit() (false)
 #endif
@@ -1383,13 +1378,13 @@ static inline pmd_t pmd_read_atomic(pmd_
  */
 static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd)
 {
-	pmd_t pmdval = pmd_read_atomic(pmd);
+	pmd_t pmdval = pmdp_get_lockless(pmd);
 	/*
 	 * The barrier will stabilize the pmdval in a register or on
 	 * the stack so that it will stop changing under the code.
 	 *
 	 * When CONFIG_TRANSPARENT_HUGEPAGE=y on x86 32bit PAE,
-	 * pmd_read_atomic is allowed to return a not atomic pmdval
+	 * pmdp_get_lockless is allowed to return a not atomic pmdval
 	 * (for example pointing to an hugepage that has never been
 	 * mapped in the pmd). The below checks will only care about
 	 * the low part of the pmd with 32bit PAE x86 anyway, with the
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -361,7 +361,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
 		 * huge or device mapping one and compute corresponding pfn
 		 * values.
 		 */
-		pmd = pmd_read_atomic(pmdp);
+		pmd = pmdp_get_lockless(pmdp);
 		barrier();
 		if (!pmd_devmap(pmd) && !pmd_trans_huge(pmd))
 			goto again;
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -862,7 +862,7 @@ static int find_pmd_or_thp_or_none(struc
 	if (!*pmd)
 		return SCAN_PMD_NULL;
 
-	pmde = pmd_read_atomic(*pmd);
+	pmde = pmdp_get_lockless(*pmd);
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 	/* See comments in pmd_none_or_trans_huge_or_clear_bad() */
--- a/mm/mapping_dirty_helpers.c
+++ b/mm/mapping_dirty_helpers.c
@@ -126,7 +126,7 @@ static int clean_record_pte(pte_t *pte,
 static int wp_clean_pmd_entry(pmd_t *pmd, unsigned long addr, unsigned long end,
 			      struct mm_walk *walk)
 {
-	pmd_t pmdval = pmd_read_atomic(pmd);
+	pmd_t pmdval = pmdp_get_lockless(pmd);
 
 	if (!pmd_trans_unstable(&pmdval))
 		return 0;
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -292,7 +292,7 @@ static unsigned long change_pte_range(st
  */
 static inline int pmd_none_or_clear_bad_unless_trans_huge(pmd_t *pmd)
 {
-	pmd_t pmdval = pmd_read_atomic(pmd);
+	pmd_t pmdval = pmdp_get_lockless(pmd);
 
 	/* See pmd_none_or_trans_huge_or_clear_bad for info on barrier */
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -613,7 +613,7 @@ static __always_inline ssize_t __mcopy_a
 			break;
 		}
 
-		dst_pmdval = pmd_read_atomic(dst_pmd);
+		dst_pmdval = pmdp_get_lockless(dst_pmd);
 		/*
 		 * If the dst_pmd is mapped as THP don't
 		 * override it and just be strict.
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -4039,9 +4039,9 @@ static void walk_pmd_range(pud_t *pud, u
 	/* walk_pte_range() may call get_next_vma() */
 	vma = args->vma;
 	for (i = pmd_index(start), addr = start; addr != end; i++, addr = next) {
-		pmd_t val = pmd_read_atomic(pmd + i);
+		pmd_t val = pmdp_get_lockless(pmd + i);
 
-		/* for pmd_read_atomic() */
+		/* for pmdp_get_lockless() */
 		barrier();
 
 		next = pmd_addr_end(addr, end);