From: Michal Hocko <mhocko@xxxxxxxx> Subject: mm: kvmalloc support __GFP_RETRY_MAYFAIL for all sizes Now that __GFP_RETRY_MAYFAIL has a reasonable semantic regardless of the request size we can drop the hackish implementation for !costly orders. __GFP_RETRY_MAYFAIL retries as long as the reclaim makes a forward progress and backs of when we are out of memory for the requested size. Therefore we do not need to enforce__GFP_NORETRY for !costly orders just to silent the oom killer anymore. Link: http://lkml.kernel.org/r/20170623085345.11304-5-mhocko@xxxxxxxxxx Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Alex Belits <alex.belits@xxxxxxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Cc: David Daney <david.daney@xxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: NeilBrown <neilb@xxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/util.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff -puN mm/util.c~mm-kvmalloc-support-__gfp_retry_mayfail-for-all-sizes mm/util.c --- a/mm/util.c~mm-kvmalloc-support-__gfp_retry_mayfail-for-all-sizes +++ a/mm/util.c @@ -339,9 +339,9 @@ EXPORT_SYMBOL(vm_mmap); * Uses kmalloc to get the memory but if the allocation fails then falls back * to the vmalloc allocator. Use kvfree for freeing the memory. * - * Reclaim modifiers - __GFP_NORETRY and __GFP_NOFAIL are not supported. __GFP_RETRY_MAYFAIL - * is supported only for large (>32kB) allocations, and it should be used only if - * kmalloc is preferable to the vmalloc fallback, due to visible performance drawbacks. + * Reclaim modifiers - __GFP_NORETRY and __GFP_NOFAIL are not supported. + * __GFP_RETRY_MAYFAIL is supported, and it should be used only if kmalloc is + * preferable to the vmalloc fallback, due to visible performance drawbacks. * * Any use of gfp flags outside of GFP_KERNEL should be consulted with mm people. */ @@ -366,13 +366,7 @@ void *kvmalloc_node(size_t size, gfp_t f if (size > PAGE_SIZE) { kmalloc_flags |= __GFP_NOWARN; - /* - * We have to override __GFP_RETRY_MAYFAIL by __GFP_NORETRY for !costly - * requests because there is no other way to tell the allocator - * that we want to fail rather than retry endlessly. - */ - if (!(kmalloc_flags & __GFP_RETRY_MAYFAIL) || - (size <= PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) + if (!(kmalloc_flags & __GFP_RETRY_MAYFAIL)) kmalloc_flags |= __GFP_NORETRY; } _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
