From c8475d144abb1e62958cc5ec281d2a9e161c1946 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso <dave@stgolabs.net> Date: Fri, 12 Dec 2014 16:54:42 -0800 Subject: [PATCH] mm/memory.c: share the i_mmap_rwsem The unmap_mapping_range family of functions do the unmapping of user pages (ultimately via zap_page_range_single) without touching the actual interval tree, thus share the lock. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Acked-by: Hugh Dickins <hughd@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- mm/memory.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index 039fab699a1ad..5afdb5b8d4e2b 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2377,12 +2377,12 @@ void unmap_mapping_range(struct address_space *mapping, details.last_index = ULONG_MAX; - i_mmap_lock_write(mapping); + i_mmap_lock_read(mapping); if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap))) unmap_mapping_range_tree(&mapping->i_mmap, &details); if (unlikely(!list_empty(&mapping->i_mmap_nonlinear))) unmap_mapping_range_list(&mapping->i_mmap_nonlinear, &details); - i_mmap_unlock_write(mapping); + i_mmap_unlock_read(mapping); } EXPORT_SYMBOL(unmap_mapping_range); -- GitLab