Re: [RFC PATCH 2/3] mm, memory_hotplug: deobfuscate migration part of offlining

From: Michal Hocko <mhocko@kernel.org>
To: David Hildenbrand <david@redhat.com>
Cc: linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
	Oscar Salvador <OSalvador@suse.com>,
	Pavel Tatashin <pasha.tatashin@oracle.com>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH 2/3] mm, memory_hotplug: deobfuscate migration part of offlining
Date: Tue, 20 Nov 2018 15:34:22 +0100	[thread overview]
Message-ID: <20181120143422.GN22247@dhcp22.suse.cz> (raw)
In-Reply-To: <f25bfa30-96cf-799c-6885-86a3a537a977@redhat.com>

On Tue 20-11-18 15:26:43, David Hildenbrand wrote:
[...]
> > +	do {
> > +		for (pfn = start_pfn; pfn;)
> > +		{
> 
> { on a new line looks weird.
> 
> > +			/* start memory hot removal */
> > +			ret = -EINTR;
> 
> I think we can move that into the "if (signal_pending(current))"
> 
> (if my eyes are not wrong, this will not be touched otherwise)

Better?

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9cd161db3061..6bc3aee30f5e 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1592,11 +1592,10 @@ static int __ref __offline_pages(unsigned long start_pfn,
 	}
 
 	do {
-		for (pfn = start_pfn; pfn;)
-		{
+		for (pfn = start_pfn; pfn;) {
 			/* start memory hot removal */
-			ret = -EINTR;
 			if (signal_pending(current)) {
+				ret = -EINTR;
 				reason = "signal backoff";
 				goto failed_removal_isolated;
 			}
-- 
Michal Hocko
SUSE Labs
