diff options
| -rw-r--r-- | include/linux/sched.h | 22 | ||||
| -rw-r--r-- | mm/page_alloc.c | 9 | ||||
| -rw-r--r-- | mm/vmscan.c | 4 |
3 files changed, 32 insertions, 3 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index e4112aa..c2182b5 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -51,6 +51,7 @@ struct sched_param { #include <linux/cred.h> #include <linux/llist.h> #include <linux/uidgid.h> +#include <linux/gfp.h> #include <asm/processor.h> @@ -1791,6 +1792,7 @@ extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, #define PF_FROZEN 0x00010000 /* frozen for system suspend */ #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ #define PF_KSWAPD 0x00040000 /* I am kswapd */ +#define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ @@ -1828,6 +1830,26 @@ extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) #define used_math() tsk_used_math(current) +/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags */ +static inline gfp_t memalloc_noio_flags(gfp_t flags) +{ + if (unlikely(current->flags & PF_MEMALLOC_NOIO)) + flags &= ~__GFP_IO; + return flags; +} + +static inline unsigned int memalloc_noio_save(void) +{ + unsigned int flags = current->flags & PF_MEMALLOC_NOIO; + current->flags |= PF_MEMALLOC_NOIO; + return flags; +} + +static inline void memalloc_noio_restore(unsigned int flags) +{ + current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; +} + /* * task->jobctl flags */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e3fb290..3ede25e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2624,10 +2624,17 @@ retry_cpuset: page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order, zonelist, high_zoneidx, alloc_flags, preferred_zone, migratetype); - if (unlikely(!page)) + if (unlikely(!page)) { + /* + * Runtime PM, block IO and its error handling path + * can deadlock because I/O on the device might not + * complete. + */ + gfp_mask = memalloc_noio_flags(gfp_mask); page = __alloc_pages_slowpath(gfp_mask, order, zonelist, high_zoneidx, nodemask, preferred_zone, migratetype); + } trace_mm_page_alloc(page, order, gfp_mask, migratetype); diff --git a/mm/vmscan.c b/mm/vmscan.c index b93968b..a68fa20 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2352,7 +2352,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order, { unsigned long nr_reclaimed; struct scan_control sc = { - .gfp_mask = gfp_mask, + .gfp_mask = (gfp_mask = memalloc_noio_flags(gfp_mask)), .may_writepage = !laptop_mode, .nr_to_reclaim = SWAP_CLUSTER_MAX, .may_unmap = 1, @@ -3313,7 +3313,7 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order) .may_unmap = !!(zone_reclaim_mode & RECLAIM_SWAP), .may_swap = 1, .nr_to_reclaim = max(nr_pages, SWAP_CLUSTER_MAX), - .gfp_mask = gfp_mask, + .gfp_mask = (gfp_mask = memalloc_noio_flags(gfp_mask)), .order = order, .priority = ZONE_RECLAIM_PRIORITY, }; |