mm: free_area_init: allow defining max_zone_pfn in descending order

Some architectures (e.g.  ARC) have the ZONE_HIGHMEM zone below the
ZONE_NORMAL.  Allowing free_area_init() parse max_zone_pfn array even it
is sorted in descending order allows using free_area_init() on such
architectures.

Add top -> down traversal of max_zone_pfn array in free_area_init() and
use the latter in ARC node/zone initialization.

[rppt@kernel.org: ARC fix]
  Link: http://lkml.kernel.org/r/20200504153901.GM14260@kernel.org
[rppt@linux.ibm.com: arc: free_area_init(): take into account PAE40 mode]
  Link: http://lkml.kernel.org/r/20200507205900.GH683243@linux.ibm.com
[akpm@linux-foundation.org: declare arch_has_descending_max_zone_pfns()]
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Hoan Tran <hoan@os.amperecomputing.com>	[arm64]
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20200412194859.12663-18-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mike Rapoport 2020-06-03 15:58:03 -07:00 committed by Linus Torvalds
parent acd3f5c441
commit 51930df580
3 changed files with 34 additions and 34 deletions

View file

@ -63,11 +63,13 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
low_mem_sz = size;
in_use = 1;
memblock_add_node(base, size, 0);
} else {
#ifdef CONFIG_HIGHMEM
high_mem_start = base;
high_mem_sz = size;
in_use = 1;
memblock_add_node(base, size, 1);
#endif
}
@ -75,6 +77,11 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
base, TO_MB(size), !in_use ? "Not used":"");
}
bool arch_has_descending_max_zone_pfns(void)
{
return !IS_ENABLED(CONFIG_ARC_HAS_PAE40);
}
/*
* First memory setup routine called from setup_arch()
* 1. setup swapper's mm @init_mm
@ -83,8 +90,7 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
*/
void __init setup_arch_memory(void)
{
unsigned long zones_size[MAX_NR_ZONES];
unsigned long zones_holes[MAX_NR_ZONES];
unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
init_mm.start_code = (unsigned long)_text;
init_mm.end_code = (unsigned long)_etext;
@ -115,7 +121,6 @@ void __init setup_arch_memory(void)
* the crash
*/
memblock_add_node(low_mem_start, low_mem_sz, 0);
memblock_reserve(CONFIG_LINUX_LINK_BASE,
__pa(_end) - CONFIG_LINUX_LINK_BASE);
@ -133,22 +138,7 @@ void __init setup_arch_memory(void)
memblock_dump_all();
/*----------------- node/zones setup --------------------------*/
memset(zones_size, 0, sizeof(zones_size));
memset(zones_holes, 0, sizeof(zones_holes));
zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
zones_holes[ZONE_NORMAL] = 0;
/*
* We can't use the helper free_area_init(zones[]) because it uses
* PAGE_OFFSET to compute the @min_low_pfn which would be wrong
* when our kernel doesn't start at PAGE_OFFSET, i.e.
* PAGE_OFFSET != CONFIG_LINUX_RAM_BASE
*/
free_area_init_node(0, /* node-id */
zones_size, /* num pages per zone */
min_low_pfn, /* first pfn of node */
zones_holes); /* holes */
max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
#ifdef CONFIG_HIGHMEM
/*
@ -168,20 +158,13 @@ void __init setup_arch_memory(void)
min_high_pfn = PFN_DOWN(high_mem_start);
max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);
zones_size[ZONE_NORMAL] = 0;
zones_holes[ZONE_NORMAL] = 0;
zones_size[ZONE_HIGHMEM] = max_high_pfn - min_high_pfn;
zones_holes[ZONE_HIGHMEM] = 0;
free_area_init_node(1, /* node-id */
zones_size, /* num pages per zone */
min_high_pfn, /* first pfn of node */
zones_holes); /* holes */
max_zone_pfn[ZONE_HIGHMEM] = max_high_pfn;
high_memory = (void *)(min_high_pfn << PAGE_SHIFT);
kmap_init();
#endif
free_area_init(max_zone_pfn);
}
/*

View file

@ -2473,6 +2473,7 @@ extern void setup_per_cpu_pageset(void);
extern int min_free_kbytes;
extern int watermark_boost_factor;
extern int watermark_scale_factor;
extern bool arch_has_descending_max_zone_pfns(void);
/* nommu.c */
extern atomic_long_t mmap_pages_allocated;

View file

@ -7408,6 +7408,15 @@ static void check_for_memory(pg_data_t *pgdat, int nid)
}
}
/*
* Some architecturs, e.g. ARC may have ZONE_HIGHMEM below ZONE_NORMAL. For
* such cases we allow max_zone_pfn sorted in the descending order
*/
bool __weak arch_has_descending_max_zone_pfns(void)
{
return false;
}
/**
* free_area_init - Initialise all pg_data_t and zone data
* @max_zone_pfn: an array of max PFNs for each zone
@ -7424,7 +7433,8 @@ static void check_for_memory(pg_data_t *pgdat, int nid)
void __init free_area_init(unsigned long *max_zone_pfn)
{
unsigned long start_pfn, end_pfn;
int i, nid;
int i, nid, zone;
bool descending;
/* Record where the zone boundaries are */
memset(arch_zone_lowest_possible_pfn, 0,
@ -7433,14 +7443,20 @@ void __init free_area_init(unsigned long *max_zone_pfn)
sizeof(arch_zone_highest_possible_pfn));
start_pfn = find_min_pfn_with_active_regions();
descending = arch_has_descending_max_zone_pfns();
for (i = 0; i < MAX_NR_ZONES; i++) {
if (i == ZONE_MOVABLE)
if (descending)
zone = MAX_NR_ZONES - i - 1;
else
zone = i;
if (zone == ZONE_MOVABLE)
continue;
end_pfn = max(max_zone_pfn[i], start_pfn);
arch_zone_lowest_possible_pfn[i] = start_pfn;
arch_zone_highest_possible_pfn[i] = end_pfn;
end_pfn = max(max_zone_pfn[zone], start_pfn);
arch_zone_lowest_possible_pfn[zone] = start_pfn;
arch_zone_highest_possible_pfn[zone] = end_pfn;
start_pfn = end_pfn;
}