linux-kernel - [v3 4/9] mm: do not zero vmemmap

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Date:   Fri,  5 May 2017 13:03:11 -0400
From:   Pavel Tatashin <pasha.tatashin@...cle.com>
To:     linux-kernel@...r.kernel.org, sparclinux@...r.kernel.org,
        linux-mm@...ck.org, linuxppc-dev@...ts.ozlabs.org,
        linux-s390@...r.kernel.org, borntraeger@...ibm.com,
        heiko.carstens@...ibm.com, davem@...emloft.net
Subject: [v3 4/9] mm: do not zero vmemmap_buf

alloc_block_buf() can either use external allocator by calling
vmemmap_alloc_block() or when available use pre-allocated vmemmap_buf
to do allocation. In either case, alloc_block_buf() knows when to zero
memory based on the "zero" argument.  This is why it is not needed to
zero vmemmap_buf beforehand. Let clients of alloc_block_buf() to
decide whether that is needed.

Signed-off-by: Pavel Tatashin <pasha.tatashin@...cle.com>
---
 mm/sparse-vmemmap.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 5d255b0..1e9508b 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -305,7 +305,7 @@ void __init sparse_mem_maps_populate_node(struct page **map_map,
 
 	size = ALIGN(size, PMD_SIZE);
 	vmemmap_buf_start = __earlyonly_bootmem_alloc(nodeid, size
-			* map_count, PMD_SIZE, __pa(MAX_DMA_ADDRESS), true);
+			* map_count, PMD_SIZE, __pa(MAX_DMA_ADDRESS), false);
 
 	if (vmemmap_buf_start) {
 		vmemmap_buf = vmemmap_buf_start;
-- 
1.7.1