As a result of bisecting the v4.10..v4.11 commit range, it was
determined that commits [1] and [2] are both responsible of a ~140ms
early startup improvement on Rcar-H3-ES20 arm64 platform.
Since Rcar Gen3 family is not NUMA, we don't define CONFIG_NUMA in the
rcar3 defconfig (which also reduces KNL binary image by ~64KB), but this
is how the boot time improvement is lost.
This patch makes optimization [2] available on UMA systems which
provide support for CONFIG_HAVE_MEMBLOCK.
Testing this change on Rcar H3-ES20-ULCB using v4.15-rc9 KNL and
vanilla arm64 defconfig + NUMA=n, a speed-up of ~139ms (from ~174ms [3]
to ~35ms [4]) is observed in the execution of memmap_init_zone().
No boot time improvement is sensed on Apollo Lake SoC.
[1] commit 0f84832fb8f9 ("arm64: defconfig: Enable NUMA and NUMA_BALANCING")
[2] commit b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible")
[3] 174ms spent in memmap_init_zone() on H3ULCB w/o this patch (NUMA=n)
[ 2.643685] On node 0 totalpages: 1015808
[ 2.643688] DMA zone: 3584 pages used for memmap
[ 2.643691] DMA zone: 0 pages reserved
[ 2.643693] DMA zone: 229376 pages, LIFO batch:31
[ 2.643696] > memmap_init_zone
[ 2.663628] < memmap_init_zone (19.932 ms)
[ 2.663632] Normal zone: 12288 pages used for memmap
[ 2.663635] Normal zone: 786432 pages, LIFO batch:31
[ 2.663637] > memmap_init_zone
[ 2.818012] < memmap_init_zone (154.375 ms)
[ 2.818041] psci: probing for conduit method from DT.
[4] 35ms spent in memmap_init_zone() on H3ULCB with this patch (NUMA=n)
[ 2.677202] On node 0 totalpages: 1015808
[ 2.677205] DMA zone: 3584 pages used for memmap
[ 2.677208] DMA zone: 0 pages reserved
[ 2.677211] DMA zone: 229376 pages, LIFO batch:31
[ 2.677213] > memmap_init_zone
[ 2.684378] < memmap_init_zone (7.165 ms)
[ 2.684382] Normal zone: 12288 pages used for memmap
[ 2.684385] Normal zone: 786432 pages, LIFO batch:31
[ 2.684387] > memmap_init_zone
[ 2.712556] < memmap_init_zone (28.169 ms)
[ 2.712584] psci: probing for conduit method from DT.
Signed-off-by: Eugeniu Rosca <erosca@xxxxxxxxxxxxxx>
Reviewed-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
include/linux/memblock.h | 1 -
include/linux/mm.h | 6 ++++++
mm/memblock.c | 2 ++
mm/page_alloc.c | 2 --
4 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 7ed0f7782d16..9efd592c5da4 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -187,7 +187,6 @@ int memblock_search_pfn_nid(unsigned long pfn, unsigned long *start_pfn,
unsigned long *end_pfn);
void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
unsigned long *out_end_pfn, int *out_nid);
-unsigned long memblock_next_valid_pfn(unsigned long pfn, unsigned long max_pfn);
/**
* for_each_mem_pfn_range - early memory pfn range iterator
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ea818ff739cd..b82b30522585 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2064,8 +2064,14 @@ extern int __meminit __early_pfn_to_nid(unsigned long pfn,
#ifdef CONFIG_HAVE_MEMBLOCK
void zero_resv_unavail(void);
+unsigned long memblock_next_valid_pfn(unsigned long pfn, unsigned long max_pfn);
#else
static inline void zero_resv_unavail(void) {}
+static inline unsigned long memblock_next_valid_pfn(unsigned long pfn,
+ unsigned long max_pfn)
+{
+ return pfn + 1;
+}
#endif
extern void set_dma_reserve(unsigned long new_dma_reserve);
diff --git a/mm/memblock.c b/mm/memblock.c
index 46aacdfa4f4d..ad48cf200e3b 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1100,6 +1100,7 @@ void __init_memblock __next_mem_pfn_range(int *idx, int nid,
if (out_nid)
*out_nid = r->nid;
}
+#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn,
unsigned long max_pfn)
@@ -1129,6 +1130,7 @@ unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn,
return min(PHYS_PFN(type->regions[right].base), max_pfn);
}
+#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
/**
* memblock_set_node - set node ID on memblock regions
* @base: base of area to set node ID for
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 76c9688b6a0a..4a3d5936a9a0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5344,14 +5344,12 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
goto not_early;
if (!early_pfn_valid(pfn)) {
-#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
/*
* Skip to the pfn preceding the next valid one (or
* end_pfn), such that we hit a valid pfn (or end_pfn)
* on our next iteration of the loop.
*/
pfn = memblock_next_valid_pfn(pfn, end_pfn) - 1;
-#endif
continue;
}
if (!early_pfn_in_nid(pfn, nid))
--
2.15.1
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