The patch titled
Subject: mm: memmap_init: iterate over memblock regions rather that check each PFN
has been removed from the -mm tree. Its filename was
mm-memmap_init-iterate-over-memblock-regions-rather-that-check-each-pfn.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Baoquan He <bhe@xxxxxxxxxx>
Subject: mm: memmap_init: iterate over memblock regions rather that check each PFN
When called during boot the memmap_init_zone() function checks if each PFN
is valid and actually belongs to the node being initialized using
early_pfn_valid() and early_pfn_in_nid().
Each such check may cost up to O(log(n)) where n is the number of memory
banks, so for large amount of memory overall time spent in early_pfn*()
becomes substantial.
Since the information is anyway present in memblock, we can iterate over
memblock memory regions in memmap_init() and only call memmap_init_zone()
for PFN ranges that are know to be valid and in the appropriate node.
[cai@xxxxxx: fix a compilation warning from Clang]
Link: http://lkml.kernel.org/r/CF6E407F-17DC-427C-8203-21979FB882EF@xxxxxx
[bhe@xxxxxxxxxx: fix the incorrect hole in fast_isolate_freepages()]
Link: http://lkml.kernel.org/r/8C537EB7-85EE-4DCF-943E-3CC0ED0DF56D@xxxxxx
Link: http://lkml.kernel.org/r/20200521014407.29690-1-bhe@xxxxxxxxxx
Link: http://lkml.kernel.org/r/20200412194859.12663-16-rppt@xxxxxxxxxx
Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Tested-by: Hoan Tran <hoan@xxxxxxxxxxxxxxxxxxxxxx> [arm64]
Cc: Brian Cain <bcain@xxxxxxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Greentime Hu <green.hu@xxxxxxxxx>
Cc: Greg Ungerer <gerg@xxxxxxxxxxxxxx>
Cc: Guan Xuetao <gxt@xxxxxxxxxx>
Cc: Guo Ren <guoren@xxxxxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: Helge Deller <deller@xxxxxx>
Cc: "James E.J. Bottomley" <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Ley Foon Tan <ley.foon.tan@xxxxxxxxx>
Cc: Mark Salter <msalter@xxxxxxxxxx>
Cc: Matt Turner <mattst88@xxxxxxxxx>
Cc: Max Filippov <jcmvbkbc@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Michal Simek <monstr@xxxxxxxxx>
Cc: Nick Hu <nickhu@xxxxxxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Stafford Horne <shorne@xxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/compaction.c | 4 +++-
mm/page_alloc.c | 43 ++++++++++++++++---------------------------
2 files changed, 19 insertions(+), 28 deletions(-)
--- a/mm/compaction.c~mm-memmap_init-iterate-over-memblock-regions-rather-that-check-each-pfn
+++ a/mm/compaction.c
@@ -1409,7 +1409,9 @@ fast_isolate_freepages(struct compact_co
cc->free_pfn = highest;
} else {
if (cc->direct_compaction && pfn_valid(min_pfn)) {
- page = pfn_to_page(min_pfn);
+ page = pageblock_pfn_to_page(min_pfn,
+ pageblock_end_pfn(min_pfn),
+ cc->zone);
cc->free_pfn = min_pfn;
}
}
--- a/mm/page_alloc.c~mm-memmap_init-iterate-over-memblock-regions-rather-that-check-each-pfn
+++ a/mm/page_alloc.c
@@ -5951,23 +5951,6 @@ overlap_memmap_init(unsigned long zone,
return false;
}
-#ifdef CONFIG_SPARSEMEM
-/* Skip PFNs that belong to non-present sections */
-static inline __meminit unsigned long next_pfn(unsigned long pfn)
-{
- const unsigned long section_nr = pfn_to_section_nr(++pfn);
-
- if (present_section_nr(section_nr))
- return pfn;
- return section_nr_to_pfn(next_present_section_nr(section_nr));
-}
-#else
-static inline __meminit unsigned long next_pfn(unsigned long pfn)
-{
- return pfn++;
-}
-#endif
-
/*
* Initially all pages are reserved - free ones are freed
* up by memblock_free_all() once the early boot process is
@@ -6007,14 +5990,6 @@ void __meminit memmap_init_zone(unsigned
* function. They do not exist on hotplugged memory.
*/
if (context == MEMMAP_EARLY) {
- if (!early_pfn_valid(pfn)) {
- pfn = next_pfn(pfn);
- continue;
- }
- if (!early_pfn_in_nid(pfn, nid)) {
- pfn++;
- continue;
- }
if (overlap_memmap_init(zone, &pfn))
continue;
if (defer_init(nid, pfn, end_pfn))
@@ -6130,9 +6105,23 @@ static void __meminit zone_init_free_lis
}
void __meminit __weak memmap_init(unsigned long size, int nid,
- unsigned long zone, unsigned long start_pfn)
+ unsigned long zone,
+ unsigned long range_start_pfn)
{
- memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY, NULL);
+ unsigned long start_pfn, end_pfn;
+ unsigned long range_end_pfn = range_start_pfn + size;
+ int i;
+
+ for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
+ start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn);
+ end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn);
+
+ if (end_pfn > start_pfn) {
+ size = end_pfn - start_pfn;
+ memmap_init_zone(size, nid, zone, start_pfn,
+ MEMMAP_EARLY, NULL);
+ }
+ }
}
static int zone_batchsize(struct zone *zone)
_
Patches currently in -mm which might be from bhe@xxxxxxxxxx are
