@@ -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
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> --- include/linux/sched/mm.h | 43 ++++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 17 deletions(-)