From: Kent Overstreet <kent.overstreet@linux.dev> mainline inclusion from mainline-v6.8-rc6 commit 3f6d5e6a468d02676244b868b210433831846127 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/ID55JW Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Our proliferation of memalloc_*_{save,restore} APIs is getting a bit silly, this adds a generic version and converts the existing save/restore functions to wrappers. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Darrick J. Wong <djwong@kernel.org> Cc: linux-mm@kvack.org Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Long Li <leo.lilong@huawei.com> --- include/linux/sched/mm.h | 43 ++++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 17 deletions(-) diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 9a19f1b42f64..f00d7ecc2adf 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -306,6 +306,24 @@ static inline void might_alloc(gfp_t gfp_mask) might_sleep_if(gfpflags_allow_blocking(gfp_mask)); } +/** + * memalloc_flags_save - Add a PF_* flag to current->flags, save old value + * + * This allows PF_* flags to be conveniently added, irrespective of current + * value, and then the old version restored with memalloc_flags_restore(). + */ +static inline unsigned memalloc_flags_save(unsigned flags) +{ + unsigned oldflags = ~current->flags & flags; + current->flags |= flags; + return oldflags; +} + +static inline void memalloc_flags_restore(unsigned flags) +{ + current->flags &= ~flags; +} + /** * memalloc_noio_save - Marks implicit GFP_NOIO allocation scope. * @@ -319,9 +337,7 @@ static inline void might_alloc(gfp_t gfp_mask) */ static inline unsigned int memalloc_noio_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC_NOIO; - current->flags |= PF_MEMALLOC_NOIO; - return flags; + return memalloc_flags_save(PF_MEMALLOC_NOIO); } /** @@ -334,7 +350,7 @@ static inline unsigned int memalloc_noio_save(void) */ static inline void memalloc_noio_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; + memalloc_flags_restore(flags); } /** @@ -350,9 +366,7 @@ static inline void memalloc_noio_restore(unsigned int flags) */ static inline unsigned int memalloc_nofs_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC_NOFS; - current->flags |= PF_MEMALLOC_NOFS; - return flags; + return memalloc_flags_save(PF_MEMALLOC_NOFS); } /** @@ -365,32 +379,27 @@ static inline unsigned int memalloc_nofs_save(void) */ static inline void memalloc_nofs_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC_NOFS) | flags; + memalloc_flags_restore(flags); } static inline unsigned int memalloc_noreclaim_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC; - current->flags |= PF_MEMALLOC; - return flags; + return memalloc_flags_save(PF_MEMALLOC); } static inline void memalloc_noreclaim_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC) | flags; + memalloc_flags_restore(flags); } static inline unsigned int memalloc_pin_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC_PIN; - - current->flags |= PF_MEMALLOC_PIN; - return flags; + return memalloc_flags_save(PF_MEMALLOC_PIN); } static inline void memalloc_pin_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC_PIN) | flags; + memalloc_flags_restore(flags); } #ifdef CONFIG_MEMCG -- 2.39.2