The patch titled
Subject: mm: remove redundant check about FAULT_FLAG_ALLOW_RETRY bit
has been added to the -mm tree. Its filename is
mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
Subject: mm: remove redundant check about FAULT_FLAG_ALLOW_RETRY bit
Since commit 4064b9827063 ("mm: allow VM_FAULT_RETRY for multiple times")
allowed VM_FAULT_RETRY for multiple times, the FAULT_FLAG_ALLOW_RETRY bit
of fault_flag will not be changed in the page fault path, so the following
check is no longer needed:
flags & FAULT_FLAG_ALLOW_RETRY
So just remove it.
Link: https://lkml.kernel.org/r/20211110123358.36511-1-zhengqi.arch@xxxxxxxxxxxxx
Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Kirill Shutemov <kirill@xxxxxxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Cc: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/alpha/mm/fault.c | 16 +++++++---------
arch/arc/mm/fault.c | 3 +--
arch/arm/mm/fault.c | 2 +-
arch/arm64/mm/fault.c | 6 ++----
arch/hexagon/mm/vm_fault.c | 8 +++-----
arch/ia64/mm/fault.c | 16 +++++++---------
arch/m68k/mm/fault.c | 18 ++++++++----------
arch/microblaze/mm/fault.c | 18 ++++++++----------
arch/mips/mm/fault.c | 19 +++++++++----------
arch/nds32/mm/fault.c | 16 +++++++---------
arch/nios2/mm/fault.c | 18 ++++++++----------
arch/openrisc/mm/fault.c | 18 ++++++++----------
arch/parisc/mm/fault.c | 18 ++++++++----------
arch/powerpc/mm/fault.c | 6 ++----
arch/riscv/mm/fault.c | 2 +-
arch/s390/mm/fault.c | 26 ++++++++++++--------------
arch/sh/mm/fault.c | 18 ++++++++----------
arch/sparc/mm/fault_32.c | 16 +++++++---------
arch/sparc/mm/fault_64.c | 16 +++++++---------
arch/um/kernel/trap.c | 8 +++-----
arch/x86/mm/fault.c | 3 +--
arch/xtensa/mm/fault.c | 17 ++++++++---------
22 files changed, 126 insertions(+), 162 deletions(-)
--- a/arch/alpha/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/alpha/mm/fault.c
@@ -165,17 +165,15 @@ retry:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /* No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /* No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/arc/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/arc/mm/fault.c
@@ -149,8 +149,7 @@ retry:
/*
* Fault retry nuances, mmap_lock already relinquished by core mm
*/
- if (unlikely((fault & VM_FAULT_RETRY) &&
- (flags & FAULT_FLAG_ALLOW_RETRY))) {
+ if (unlikely(fault & VM_FAULT_RETRY)) {
flags |= FAULT_FLAG_TRIED;
goto retry;
}
--- a/arch/arm64/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/arm64/mm/fault.c
@@ -606,10 +606,8 @@ retry:
}
if (fault & VM_FAULT_RETRY) {
- if (mm_flags & FAULT_FLAG_ALLOW_RETRY) {
- mm_flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
+ mm_flags |= FAULT_FLAG_TRIED;
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/arm/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/arm/mm/fault.c
@@ -312,7 +312,7 @@ retry:
return 0;
}
- if (!(fault & VM_FAULT_ERROR) && flags & FAULT_FLAG_ALLOW_RETRY) {
+ if (!(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_RETRY) {
flags |= FAULT_FLAG_TRIED;
goto retry;
--- a/arch/hexagon/mm/vm_fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/hexagon/mm/vm_fault.c
@@ -98,11 +98,9 @@ good_area:
/* The most common case -- we are done. */
if (likely(!(fault & VM_FAULT_ERROR))) {
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/ia64/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/ia64/mm/fault.c
@@ -156,17 +156,15 @@ retry:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /* No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /* No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/m68k/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/m68k/mm/fault.c
@@ -153,18 +153,16 @@ good_area:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /*
- * No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /*
+ * No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/microblaze/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/microblaze/mm/fault.c
@@ -232,18 +232,16 @@ good_area:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /*
- * No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /*
+ * No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/mips/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/mips/mm/fault.c
@@ -171,18 +171,17 @@ good_area:
goto do_sigbus;
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
- /*
- * No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
+ /*
+ * No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
+
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/nds32/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/nds32/mm/fault.c
@@ -230,16 +230,14 @@ good_area:
goto bad_area;
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /* No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
- goto retry;
- }
+ /* No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/nios2/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/nios2/mm/fault.c
@@ -149,18 +149,16 @@ good_area:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /*
- * No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /*
+ * No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/openrisc/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/openrisc/mm/fault.c
@@ -177,18 +177,16 @@ good_area:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- /*RGD modeled on Cris */
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ /*RGD modeled on Cris */
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /* No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /* No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/parisc/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/parisc/mm/fault.c
@@ -324,16 +324,14 @@ good_area:
goto bad_area;
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- /*
- * No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
- flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
+ if (fault & VM_FAULT_RETRY) {
+ /*
+ * No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
+ flags |= FAULT_FLAG_TRIED;
+ goto retry;
}
mmap_read_unlock(mm);
return;
--- a/arch/powerpc/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/powerpc/mm/fault.c
@@ -516,10 +516,8 @@ retry:
* case.
*/
if (unlikely(fault & VM_FAULT_RETRY)) {
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
+ flags |= FAULT_FLAG_TRIED;
+ goto retry;
}
mmap_read_unlock(current->mm);
--- a/arch/riscv/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/riscv/mm/fault.c
@@ -330,7 +330,7 @@ good_area:
if (fault_signal_pending(fault, regs))
return;
- if (unlikely((fault & VM_FAULT_RETRY) && (flags & FAULT_FLAG_ALLOW_RETRY))) {
+ if (unlikely(fault & VM_FAULT_RETRY)) {
flags |= FAULT_FLAG_TRIED;
/*
--- a/arch/s390/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/s390/mm/fault.c
@@ -452,21 +452,19 @@ retry:
if (unlikely(fault & VM_FAULT_ERROR))
goto out_up;
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- if (IS_ENABLED(CONFIG_PGSTE) && gmap &&
- (flags & FAULT_FLAG_RETRY_NOWAIT)) {
- /* FAULT_FLAG_RETRY_NOWAIT has been set,
- * mmap_lock has not been released */
- current->thread.gmap_pfault = 1;
- fault = VM_FAULT_PFAULT;
- goto out_up;
- }
- flags &= ~FAULT_FLAG_RETRY_NOWAIT;
- flags |= FAULT_FLAG_TRIED;
- mmap_read_lock(mm);
- goto retry;
+ if (fault & VM_FAULT_RETRY) {
+ if (IS_ENABLED(CONFIG_PGSTE) && gmap &&
+ (flags & FAULT_FLAG_RETRY_NOWAIT)) {
+ /* FAULT_FLAG_RETRY_NOWAIT has been set,
+ * mmap_lock has not been released */
+ current->thread.gmap_pfault = 1;
+ fault = VM_FAULT_PFAULT;
+ goto out_up;
}
+ flags &= ~FAULT_FLAG_RETRY_NOWAIT;
+ flags |= FAULT_FLAG_TRIED;
+ mmap_read_lock(mm);
+ goto retry;
}
if (IS_ENABLED(CONFIG_PGSTE) && gmap) {
address = __gmap_link(gmap, current->thread.gmap_addr,
--- a/arch/sh/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/sh/mm/fault.c
@@ -485,17 +485,15 @@ good_area:
if (mm_fault_error(regs, error_code, address, fault))
return;
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /*
- * No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
- goto retry;
- }
+ /*
+ * No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/sparc/mm/fault_32.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/sparc/mm/fault_32.c
@@ -200,17 +200,15 @@ good_area:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /* No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /* No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/sparc/mm/fault_64.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/sparc/mm/fault_64.c
@@ -437,17 +437,15 @@ good_area:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- /* No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ /* No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
- goto retry;
- }
+ goto retry;
}
mmap_read_unlock(mm);
--- a/arch/um/kernel/trap.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/um/kernel/trap.c
@@ -87,12 +87,10 @@ good_area:
}
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
+ goto retry;
}
pmd = pmd_off(mm, address);
--- a/arch/x86/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/x86/mm/fault.c
@@ -1413,8 +1413,7 @@ good_area:
* and if there is a fatal signal pending there is no guarantee
* that we made any progress. Handle this case first.
*/
- if (unlikely((fault & VM_FAULT_RETRY) &&
- (flags & FAULT_FLAG_ALLOW_RETRY))) {
+ if (unlikely(fault & VM_FAULT_RETRY)) {
flags |= FAULT_FLAG_TRIED;
goto retry;
}
--- a/arch/xtensa/mm/fault.c~mm-remove-redundant-check-about-fault_flag_allow_retry-bit
+++ a/arch/xtensa/mm/fault.c
@@ -127,17 +127,16 @@ good_area:
goto do_sigbus;
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
- /* No need to mmap_read_unlock(mm) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
+ /* No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
+
+ goto retry;
}
mmap_read_unlock(mm);
_
Patches currently in -mm which might be from zhengqi.arch@xxxxxxxxxxxxx are
mm-remove-redundant-check-about-fault_flag_allow_retry-bit.patch
