Commit ca9a46f8 authored Sep 23, 2019 by David Hildenbrand Committed by Linus Torvalds Sep 24, 2019

mm/memory_hotplug: online_pages cannot be 0 in online_pages()

walk_system_ram_range() will fail with -EINVAL in case
online_pages_range() was never called (== no resource applicable in the
range).  Otherwise, we will always call online_pages_range() with nr_pages
> 0 and, therefore, have online_pages > 0.

Remove that special handling.

Link: http://lkml.kernel.org/r/20190814154109.3448-6-david@redhat.com


Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent bd02cc01

mm/memory_hotplug.c

+9 −13

Original line number	Diff line number	Diff line
		@@ -853,6 +853,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
		ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
		online_pages_range);
		if (ret) {
		/* not a single memory resource was applicable */
		if (need_zonelists_rebuild)
		zone_pcp_reset(zone);
		goto failed_addition;
		@@ -866,26 +867,21 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ

		shuffle_zone(zone);

		if (onlined_pages) {
		node_states_set_node(nid, &arg);
		if (need_zonelists_rebuild)
		build_all_zonelists(NULL);
		else
		zone_pcp_update(zone);
		}

		init_per_zone_wmark_min();

		if (onlined_pages) {
		kswapd_run(nid);
		kcompactd_run(nid);
		}

		vm_total_pages = nr_free_pagecache_pages();

		writeback_set_ratelimit();

		if (onlined_pages)
		memory_notify(MEM_ONLINE, &arg);
		mem_hotplug_done();
		return 0;

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