mm: don't track number of pages during deferred initialization

Deferred page init used to report the number of pages initialized:

  node 0 initialised, 32439114 pages in 97ms

Tracking this makes the code more complicated when using multiple threads.
Given that the statistic probably has limited value, especially since a
zone grows on demand so that the page count can vary, just remove it.

The boot message now looks like

  node 0 deferred pages initialised in 97ms
Suggested-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200527173608.2885243-6-daniel.m.jordan@oracle.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -1820,7 +1820,7 @@ static int __init deferred_init_memmap(void *data)
 {
 	pg_data_t *pgdat = data;
 	const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
-	unsigned long spfn = 0, epfn = 0, nr_pages = 0;
+	unsigned long spfn = 0, epfn = 0;
 	unsigned long first_init_pfn, flags;
 	unsigned long start = jiffies;
 	struct zone *zone;
@@ -1869,15 +1869,15 @@ static int __init deferred_init_memmap(void *data)
 	 * allocator.
 	 */
 	while (spfn < epfn) {
-		nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn);
+		deferred_init_maxorder(&i, zone, &spfn, &epfn);
 		cond_resched();
 	}
 zone_empty:
 	/* 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",
-		pgdat->node_id,	nr_pages, jiffies_to_msecs(jiffies - start));
+	pr_info("node %d deferred pages initialised in %ums\n",
+		pgdat->node_id, jiffies_to_msecs(jiffies - start));
 
 	pgdat_init_report_one_done();
 	return 0;