Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 56ec43d8 authored by Alexander Duyck's avatar Alexander Duyck Committed by Linus Torvalds
Browse files

mm: drop meminit_pfn_in_nid as it is redundant 

As best as I can tell the meminit_pfn_in_nid call is completely redundant.
The deferred memory initialization is already making use of
for_each_free_mem_range which in turn will call into __next_mem_range
which will only return a memory range if it matches the node ID provided
assuming it is not NUMA_NO_NODE.

I am operating on the assumption that there are no zones or pgdata_t
structures that have a NUMA node of NUMA_NO_NODE associated with them.  If
that is the case then __next_mem_range will never return a memory range
that doesn't match the zone's node ID and as such the check is redundant.

So one piece I would like to verify on this is if this works for ia64.
Technically it was using a different approach to get the node ID, but it
seems to have the node ID also encoded into the memblock.  So I am
assuming this is okay, but would like to get confirmation on that.

On my x86_64 test system with 384GB of memory per node I saw a reduction
in initialization time from 2.80s to 1.85s as a result of this patch.

Link: http://lkml.kernel.org/r/20190405221219.12227.93957.stgit@localhost.localdomain


Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@linux.intel.com>
Reviewed-by: default avatarPavel Tatashin <pavel.tatashin@microsoft.com>
Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <yi.z.zhang@linux.intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 5470dea4

mm/page_alloc.c

+14 −37
Original line number Diff line number Diff line
@@ -1416,36 +1416,22 @@ int __meminit early_pfn_to_nid(unsigned long pfn) 
#endif



#ifdef CONFIG_NODES_SPAN_OTHER_NODES

static inline bool __meminit __maybe_unused

meminit_pfn_in_nid(unsigned long pfn, int node,

		   struct mminit_pfnnid_cache *state)

/* Only safe to use early in boot when initialisation is single-threaded */

static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node)

{

	int nid;



	nid = __early_pfn_to_nid(pfn, state);

	nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);

	if (nid >= 0 && nid != node)

		return false;

	return true;

}



/* Only safe to use early in boot when initialisation is single-threaded */

static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node)

{

	return meminit_pfn_in_nid(pfn, node, &early_pfnnid_cache);

}



#else



static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node)

{

	return true;

}

static inline bool __meminit  __maybe_unused

meminit_pfn_in_nid(unsigned long pfn, int node,

		   struct mminit_pfnnid_cache *state)

{

	return true;

}

#endif
@@ -1574,21 +1560,13 @@ static inline void __init pgdat_init_report_one_done(void) 
 *

 * Then, we check if a current large page is valid by only checking the validity

 * of the head pfn.

 *

 * Finally, meminit_pfn_in_nid is checked on systems where pfns can interleave

 * within a node: a pfn is between start and end of a node, but does not belong

 * to this memory node.

 */

static inline bool __init

deferred_pfn_valid(int nid, unsigned long pfn,

		   struct mminit_pfnnid_cache *nid_init_state)

static inline bool __init deferred_pfn_valid(unsigned long pfn)

{

	if (!pfn_valid_within(pfn))

		return false;

	if (!(pfn & (pageblock_nr_pages - 1)) && !pfn_valid(pfn))

		return false;

	if (!meminit_pfn_in_nid(pfn, nid, nid_init_state))

		return false;

	return true;

}
@@ -1596,15 +1574,14 @@ deferred_pfn_valid(int nid, unsigned long pfn, 
 * Free pages to buddy allocator. Try to free aligned pages in

 * pageblock_nr_pages sizes.

 */

static void __init deferred_free_pages(int nid, int zid, unsigned long pfn,

static void __init deferred_free_pages(unsigned long pfn,

				       unsigned long end_pfn)

{

	struct mminit_pfnnid_cache nid_init_state = { };

	unsigned long nr_pgmask = pageblock_nr_pages - 1;

	unsigned long nr_free = 0;



	for (; pfn < end_pfn; pfn++) {

		if (!deferred_pfn_valid(nid, pfn, &nid_init_state)) {

		if (!deferred_pfn_valid(pfn)) {

			deferred_free_range(pfn - nr_free, nr_free);

			nr_free = 0;

		} else if (!(pfn & nr_pgmask)) {
@@ -1624,17 +1601,18 @@ static void __init deferred_free_pages(int nid, int zid, unsigned long pfn, 
 * by performing it only once every pageblock_nr_pages.

 * Return number of pages initialized.

 */

static unsigned long  __init deferred_init_pages(int nid, int zid,

static unsigned long  __init deferred_init_pages(struct zone *zone,

						 unsigned long pfn,

						 unsigned long end_pfn)

{

	struct mminit_pfnnid_cache nid_init_state = { };

	unsigned long nr_pgmask = pageblock_nr_pages - 1;

	int nid = zone_to_nid(zone);

	unsigned long nr_pages = 0;

	int zid = zone_idx(zone);

	struct page *page = NULL;



	for (; pfn < end_pfn; pfn++) {

		if (!deferred_pfn_valid(nid, pfn, &nid_init_state)) {

		if (!deferred_pfn_valid(pfn)) {

			page = NULL;

			continue;

		} else if (!page || !(pfn & nr_pgmask)) {
@@ -1697,12 +1675,12 @@ static int __init deferred_init_memmap(void *data) 
	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));

		nr_pages += deferred_init_pages(nid, zid, spfn, epfn);

		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));

		deferred_free_pages(nid, zid, spfn, epfn);

		deferred_free_pages(spfn, epfn);

	}

	pgdat_resize_unlock(pgdat, &flags);
@@ -1734,7 +1712,6 @@ static int __init deferred_init_memmap(void *data) 
static noinline bool __init

deferred_grow_zone(struct zone *zone, unsigned int order)

{

	int zid = zone_idx(zone);

	int nid = zone_to_nid(zone);

	pg_data_t *pgdat = NODE_DATA(nid);

	unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
@@ -1784,7 +1761,7 @@ deferred_grow_zone(struct zone *zone, unsigned int order) 
		while (spfn < epfn && nr_pages < nr_pages_needed) {

			t = ALIGN(spfn + PAGES_PER_SECTION, PAGES_PER_SECTION);

			first_deferred_pfn = min(t, epfn);

			nr_pages += deferred_init_pages(nid, zid, spfn,

			nr_pages += deferred_init_pages(zone, spfn,

							first_deferred_pfn);

			spfn = first_deferred_pfn;

		}
@@ -1796,7 +1773,7 @@ deferred_grow_zone(struct zone *zone, unsigned int order) 
	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));

		deferred_free_pages(nid, zid, spfn, epfn);

		deferred_free_pages(spfn, epfn);



		if (first_deferred_pfn == epfn)

			break;