lkml.org 
[lkml]   [2019]   [Apr]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [mm PATCH v7 3/4] mm: Implement new zone specific memblock iterator
On Fri, Apr 05, 2019 at 03:12:25PM -0700, Alexander Duyck wrote:
> From: Alexander Duyck <alexander.h.duyck@linux.intel.com>
>
> Introduce a new iterator for_each_free_mem_pfn_range_in_zone.
>
> This iterator will take care of making sure a given memory range provided
> is in fact contained within a zone. It takes are of all the bounds checking
> we were doing in deferred_grow_zone, and deferred_init_memmap. In addition
> it should help to speed up the search a bit by iterating until the end of a
> range is greater than the start of the zone pfn range, and will exit
> completely if the start is beyond the end of the zone.
>
> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>

Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>

> ---
> include/linux/memblock.h | 25 ++++++++++++++++++
> mm/memblock.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++
> mm/page_alloc.c | 31 +++++++++-------------
> 3 files changed, 101 insertions(+), 19 deletions(-)
>
> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> index 294d5d80e150..f8b78892b977 100644
> --- a/include/linux/memblock.h
> +++ b/include/linux/memblock.h
> @@ -240,6 +240,31 @@ void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
> i >= 0; __next_mem_pfn_range(&i, nid, p_start, p_end, p_nid))
> #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
>
> +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
> +void __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
> + unsigned long *out_spfn,
> + unsigned long *out_epfn);
> +/**
> + * for_each_free_mem_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))
> +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
> +
> /**
> * for_each_free_mem_range - iterate through free memblock areas
> * @i: u64 used as loop variable
> diff --git a/mm/memblock.c b/mm/memblock.c
> index e7665cf914b1..28fa8926d9f8 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1255,6 +1255,70 @@ int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
> return 0;
> }
> #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
> +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
> +/**
> + * __next_mem_pfn_range_in_zone - iterator for for_each_*_range_in_zone()
> + *
> + * @idx: pointer to u64 loop variable
> + * @zone: zone in which all of the memory blocks reside
> + * @out_spfn: ptr to ulong for start pfn of the range, can be %NULL
> + * @out_epfn: ptr to ulong for end pfn of the range, can be %NULL
> + *
> + * This function is meant to be a zone/pfn specific wrapper for the
> + * for_each_mem_range type iterators. Specifically they are used in the
> + * deferred memory init routines and as such we were duplicating much of
> + * this logic throughout the code. So instead of having it in multiple
> + * locations it seemed like it would make more sense to centralize this to
> + * one new iterator that does everything they need.
> + */
> +void __init_memblock
> +__next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
> + unsigned long *out_spfn, unsigned long *out_epfn)
> +{
> + int zone_nid = zone_to_nid(zone);
> + phys_addr_t spa, epa;
> + int nid;
> +
> + __next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
> + &memblock.memory, &memblock.reserved,
> + &spa, &epa, &nid);
> +
> + while (*idx != U64_MAX) {
> + unsigned long epfn = PFN_DOWN(epa);
> + unsigned long spfn = PFN_UP(spa);
> +
> + /*
> + * Verify the end is at least past the start of the zone and
> + * that we have at least one PFN to initialize.
> + */
> + if (zone->zone_start_pfn < epfn && spfn < epfn) {
> + /* if we went too far just stop searching */
> + if (zone_end_pfn(zone) <= spfn) {
> + *idx = U64_MAX;
> + break;
> + }
> +
> + if (out_spfn)
> + *out_spfn = max(zone->zone_start_pfn, spfn);
> + if (out_epfn)
> + *out_epfn = min(zone_end_pfn(zone), epfn);
> +
> + return;
> + }
> +
> + __next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
> + &memblock.memory, &memblock.reserved,
> + &spa, &epa, &nid);
> + }
> +
> + /* signal end of iteration */
> + if (out_spfn)
> + *out_spfn = ULONG_MAX;
> + if (out_epfn)
> + *out_epfn = 0;
> +}
> +
> +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
>
> /**
> * memblock_alloc_range_nid - allocate boot memory block
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 2d2bca9803d2..61467e28c966 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -1613,11 +1613,9 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
> static int __init deferred_init_memmap(void *data)
> {
> pg_data_t *pgdat = data;
> - int nid = pgdat->node_id;
> unsigned long start = jiffies;
> unsigned long nr_pages = 0;
> unsigned long spfn, epfn, first_init_pfn, flags;
> - phys_addr_t spa, epa;
> int zid;
> struct zone *zone;
> const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
> @@ -1654,14 +1652,12 @@ static int __init deferred_init_memmap(void *data)
> * freeing pages we can access pages that are ahead (computing buddy
> * page in __free_one_page()).
> */
> - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) {
> - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa));
> - epfn = min_t(unsigned long, zone_end_pfn(zone), PFN_DOWN(epa));
> + for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) {
> + spfn = max_t(unsigned long, first_init_pfn, spfn);
> nr_pages += deferred_init_pages(zone, spfn, epfn);
> }
> - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) {
> - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa));
> - epfn = min_t(unsigned long, zone_end_pfn(zone), PFN_DOWN(epa));
> + for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) {
> + spfn = max_t(unsigned long, first_init_pfn, spfn);
> deferred_free_pages(spfn, epfn);
> }
> pgdat_resize_unlock(pgdat, &flags);
> @@ -1669,8 +1665,8 @@ static int __init deferred_init_memmap(void *data)
> /* Sanity check that the next zone really is unpopulated */
> WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone));
>
> - pr_info("node %d initialised, %lu pages in %ums\n", nid, nr_pages,
> - jiffies_to_msecs(jiffies - start));
> + pr_info("node %d initialised, %lu pages in %ums\n",
> + pgdat->node_id, nr_pages, jiffies_to_msecs(jiffies - start));
>
> pgdat_init_report_one_done();
> return 0;
> @@ -1694,13 +1690,11 @@ static int __init deferred_init_memmap(void *data)
> static noinline bool __init
> deferred_grow_zone(struct zone *zone, unsigned int order)
> {
> - int nid = zone_to_nid(zone);
> - pg_data_t *pgdat = NODE_DATA(nid);
> unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
> + pg_data_t *pgdat = zone->zone_pgdat;
> unsigned long nr_pages = 0;
> unsigned long first_init_pfn, spfn, epfn, t, flags;
> unsigned long first_deferred_pfn = pgdat->first_deferred_pfn;
> - phys_addr_t spa, epa;
> u64 i;
>
> /* Only the last zone may have deferred pages */
> @@ -1736,9 +1730,8 @@ static int __init deferred_init_memmap(void *data)
> return false;
> }
>
> - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) {
> - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa));
> - epfn = min_t(unsigned long, zone_end_pfn(zone), PFN_DOWN(epa));
> + for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) {
> + spfn = max_t(unsigned long, first_init_pfn, spfn);
>
> while (spfn < epfn && nr_pages < nr_pages_needed) {
> t = ALIGN(spfn + PAGES_PER_SECTION, PAGES_PER_SECTION);
> @@ -1752,9 +1745,9 @@ static int __init deferred_init_memmap(void *data)
> break;
> }
>
> - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) {
> - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa));
> - epfn = min_t(unsigned long, first_deferred_pfn, PFN_DOWN(epa));
> + for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) {
> + spfn = max_t(unsigned long, first_init_pfn, spfn);
> + epfn = min_t(unsigned long, first_deferred_pfn, epfn);
> deferred_free_pages(spfn, epfn);
>
> if (first_deferred_pfn == epfn)
>

--
Sincerely yours,
Mike.

\
 
 \ /
  Last update: 2019-04-06 15:04    [W:0.057 / U:10.740 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site