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mm/mm_init.c: not always search next deferred_init_pfn from very beginning

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In function deferred_init_memmap(), we call
deferred_init_mem_pfn_range_in_zone() to get the next deferred_init_pfn.
But we always search it from the very beginning.

Since we save the index in i, we can leverage this to search from i next
time.

[rppt refine the comment]

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Link: https://lore.kernel.org/all/20240605071339.15330-1-richard.weiyang@gmail.com
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
This commit is contained in:
Wei Yang 2024-06-05 07:13:39 +00:00 committed by Mike Rapoport (IBM)
parent 544b8e14c2
commit f1180fd2a7
2 changed files with 14 additions and 28 deletions
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19
include/linux/memblock.h
View File

@ -299,25 +299,6 @@ void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
void __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone, void __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
unsigned long *out_spfn, unsigned long *out_spfn,
unsigned long *out_epfn); unsigned long *out_epfn);
/**
* for_each_free_mem_pfn_range_in_zone - iterate through zone specific free
* memblock areas
* @i: u64 used as loop variable
* @zone: zone in which all of the memory blocks reside
* @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
* @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
*
* Walks over free (memory && !reserved) areas of memblock in a specific
* zone. Available once memblock and an empty zone is initialized. The main
* assumption is that the zone start, end, and pgdat have been associated.
* This way we can use the zone to determine NUMA node, and if a given part
* of the memblock is valid for the zone.
*/
#define for_each_free_mem_pfn_range_in_zone(i, zone, p_start, p_end) \
for (i = 0, \
__next_mem_pfn_range_in_zone(&i, zone, p_start, p_end); \
i != U64_MAX; \
__next_mem_pfn_range_in_zone(&i, zone, p_start, p_end))
/** /**
* for_each_free_mem_pfn_range_in_zone_from - iterate through zone specific * for_each_free_mem_pfn_range_in_zone_from - iterate through zone specific

23
mm/mm_init.c
View File

@ -2021,24 +2021,29 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
} }
/* /*
* This function is meant to pre-load the iterator for the zone init. * This function is meant to pre-load the iterator for the zone init from
* Specifically it walks through the ranges until we are caught up to the * a given point.
* first_init_pfn value and exits there. If we never encounter the value we * Specifically it walks through the ranges starting with initial index
* return false indicating there are no valid ranges left. * passed to it until we are caught up to the first_init_pfn value and
* exits there. If we never encounter the value we return false indicating
* there are no valid ranges left.
*/ */
static bool __init static bool __init
deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone, deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone,
unsigned long *spfn, unsigned long *epfn, unsigned long *spfn, unsigned long *epfn,
unsigned long first_init_pfn) unsigned long first_init_pfn)
{ {
u64 j; u64 j = *i;
if (j == 0)
__next_mem_pfn_range_in_zone(&j, zone, spfn, epfn);
/* /*
* Start out by walking through the ranges in this zone that have * Start out by walking through the ranges in this zone that have
* already been initialized. We don't need to do anything with them * already been initialized. We don't need to do anything with them
* so we just need to flush them out of the system. * so we just need to flush them out of the system.
*/ */
for_each_free_mem_pfn_range_in_zone(j, zone, spfn, epfn) { for_each_free_mem_pfn_range_in_zone_from(j, zone, spfn, epfn) {
if (*epfn <= first_init_pfn) if (*epfn <= first_init_pfn)
continue; continue;
if (*spfn < first_init_pfn) if (*spfn < first_init_pfn)
@ -2110,7 +2115,7 @@ deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn,
{ {
unsigned long spfn, epfn; unsigned long spfn, epfn;
struct zone *zone = arg; struct zone *zone = arg;
u64 i; u64 i = 0;
deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, start_pfn); deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, start_pfn);
@ -2141,7 +2146,7 @@ static int __init deferred_init_memmap(void *data)
unsigned long start = jiffies; unsigned long start = jiffies;
struct zone *zone; struct zone *zone;
int max_threads; int max_threads;
u64 i; u64 i = 0;
/* Bind memory initialisation thread to a local node if possible */ /* Bind memory initialisation thread to a local node if possible */
if (!cpumask_empty(cpumask)) if (!cpumask_empty(cpumask))
@ -2216,7 +2221,7 @@ bool __init deferred_grow_zone(struct zone *zone, unsigned int order)
unsigned long first_deferred_pfn = pgdat->first_deferred_pfn; unsigned long first_deferred_pfn = pgdat->first_deferred_pfn;
unsigned long spfn, epfn, flags; unsigned long spfn, epfn, flags;
unsigned long nr_pages = 0; unsigned long nr_pages = 0;
u64 i; u64 i = 0;
/* Only the last zone may have deferred pages */ /* Only the last zone may have deferred pages */
if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat)) if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat))