Commit eab0af90 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

mm: introduce PF_MEMALLOC_NORECLAIM, PF_MEMALLOC_NOWARN 



Introduce PF_MEMALLOC_* equivalents of some GFP_ flags:

PF_MEMALLOC_NORECLAIM	-> GFP_NOWAIT
PF_MEMALLOC_NOWARN	-> __GFP_NOWARN

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
Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 3f6d5e6a

include/linux/sched.h

+2 −2
Original line number Diff line number Diff line
@@ -1636,8 +1636,8 @@ extern struct pid *cad_pid; 
						 * I am cleaning dirty pages from some other bdi. */

#define PF_KTHREAD		0x00200000	/* I am a kernel thread */

#define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */

#define PF__HOLE__00800000	0x00800000

#define PF__HOLE__01000000	0x01000000

#define PF_MEMALLOC_NORECLAIM	0x00800000	/* All allocation requests will clear __GFP_DIRECT_RECLAIM */

#define PF_MEMALLOC_NOWARN	0x01000000	/* All allocation requests will inherit __GFP_NOWARN */

#define PF__HOLE__02000000	0x02000000

#define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */

#define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */

include/linux/sched/mm.h

+13 −4
Original line number Diff line number Diff line
@@ -236,16 +236,25 @@ static inline gfp_t current_gfp_context(gfp_t flags) 
{

	unsigned int pflags = READ_ONCE(current->flags);



	if (unlikely(pflags & (PF_MEMALLOC_NOIO | PF_MEMALLOC_NOFS | PF_MEMALLOC_PIN))) {

	if (unlikely(pflags & (PF_MEMALLOC_NOIO |

			       PF_MEMALLOC_NOFS |

			       PF_MEMALLOC_NORECLAIM |

			       PF_MEMALLOC_NOWARN |

			       PF_MEMALLOC_PIN))) {

		/*

		 * NOIO implies both NOIO and NOFS and it is a weaker context

		 * so always make sure it makes precedence

		 * Stronger flags before weaker flags:

		 * NORECLAIM implies NOIO, which in turn implies NOFS

		 */

		if (pflags & PF_MEMALLOC_NOIO)

		if (pflags & PF_MEMALLOC_NORECLAIM)

			flags &= ~__GFP_DIRECT_RECLAIM;

		else if (pflags & PF_MEMALLOC_NOIO)

			flags &= ~(__GFP_IO | __GFP_FS);

		else if (pflags & PF_MEMALLOC_NOFS)

			flags &= ~__GFP_FS;



		if (pflags & PF_MEMALLOC_NOWARN)

			flags |= __GFP_NOWARN;



		if (pflags & PF_MEMALLOC_PIN)

			flags &= ~__GFP_MOVABLE;

	}