Hi,
Repost of [1] rebased on 5.0-rc3 + accumulated Acked-by/Reviewed-by.
No code changes since v1.
Please consider applying.
[1] http://lists.infradead.org/pipermail/linux-snps-arc/2019-January/005201.html
Thx,
-Vineet
Vineet Gupta (3):
coredump: Replace opencoded set_mask_bits()
fs: inode_set_flags() replace opencoded set_mask_bits()
bitops.h: set_mask_bits() to return old value
fs/exec.c | 7 +------
fs/inode.c | 8 +-------
include/linux/bitops.h | 2 +-
3 files changed, 3 insertions(+), 14 deletions(-)
--
2.7.4
| > Also, set_mask_bits is used in fs quite a bit and we can possibly come up
| > with a generic llsc based implementation (w/o the cmpxchg loop)
|
| May I also suggest changing the return value of set_mask_bits() to old.
|
| You can compute the new value given old, but you cannot compute the old
| value given new, therefore old is the better return value. Also, no
| current user seems to use the return value, so changing it is without
| risk.
Link: http://lkml.kernel.org/g/[email protected]
Suggested-by: Peter Zijlstra <[email protected]>
Cc: Miklos Szeredi <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Chris Wilson <[email protected]>
Cc: Andrew Morton <[email protected]>
Reviewed-by: Anthony Yznaga <[email protected]>
Acked-by: Will Deacon <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
---
include/linux/bitops.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 705f7c442691..602af23b98c7 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -246,7 +246,7 @@ static __always_inline void __assign_bit(long nr, volatile unsigned long *addr,
new__ = (old__ & ~mask__) | bits__; \
} while (cmpxchg(ptr, old__, new__) != old__); \
\
- new__; \
+ old__; \
})
#endif
--
2.7.4
It seems that 5f16f3225b0624 and 00a1a053ebe5, both with same commitlog
("ext4: atomically set inode->i_flags in ext4_set_inode_flags()")
introduced the set_mask_bits API, but somehow missed not using it in
ext4 in the end
Also, set_mask_bits is used in fs quite a bit and we can possibly come up
with a generic llsc based implementation (w/o the cmpxchg loop)
Cc: Alexander Viro <[email protected]>
Cc: Theodore Ts'o <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Cc: [email protected]
Cc: [email protected]
Reviewed-by: Anthony Yznaga <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
---
fs/inode.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/fs/inode.c b/fs/inode.c
index 0cd47fe0dbe5..799b0c4beda8 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2096,14 +2096,8 @@ EXPORT_SYMBOL(inode_dio_wait);
void inode_set_flags(struct inode *inode, unsigned int flags,
unsigned int mask)
{
- unsigned int old_flags, new_flags;
-
WARN_ON_ONCE(flags & ~mask);
- do {
- old_flags = READ_ONCE(inode->i_flags);
- new_flags = (old_flags & ~mask) | flags;
- } while (unlikely(cmpxchg(&inode->i_flags, old_flags,
- new_flags) != old_flags));
+ set_mask_bits(&inode->i_flags, mask, flags);
}
EXPORT_SYMBOL(inode_set_flags);
--
2.7.4
Cc: Alexander Viro <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/g/[email protected]
Reviewed-by: Anthony Yznaga <[email protected]>
Acked-by: Oleg Nesterov <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
---
fs/exec.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index fb72d36f7823..df7f05362283 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1944,15 +1944,10 @@ EXPORT_SYMBOL(set_binfmt);
*/
void set_dumpable(struct mm_struct *mm, int value)
{
- unsigned long old, new;
-
if (WARN_ON((unsigned)value > SUID_DUMP_ROOT))
return;
- do {
- old = READ_ONCE(mm->flags);
- new = (old & ~MMF_DUMPABLE_MASK) | value;
- } while (cmpxchg(&mm->flags, old, new) != old);
+ set_mask_bits(&mm->flags, MMF_DUMPABLE_MASK, value);
}
SYSCALL_DEFINE3(execve,
--
2.7.4
On 1/23/19 12:33 PM, Vineet Gupta wrote:
> Hi,
>
> Repost of [1] rebased on 5.0-rc3 + accumulated Acked-by/Reviewed-by.
> No code changes since v1.
>
> Please consider applying.
>
> [1] http://lists.infradead.org/pipermail/linux-snps-arc/2019-January/005201.html
>
> Thx,
> -Vineet
Ping ! @Peter, @Arnd are you happy with this. If so, Andrew can you please add
this via mm tree or do i need to pester the respective maintainers !
Thx,
-Vineet
>
> Vineet Gupta (3):
> coredump: Replace opencoded set_mask_bits()
> fs: inode_set_flags() replace opencoded set_mask_bits()
> bitops.h: set_mask_bits() to return old value
>
> fs/exec.c | 7 +------
> fs/inode.c | 8 +-------
> include/linux/bitops.h | 2 +-
> 3 files changed, 3 insertions(+), 14 deletions(-)
>