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Date: Mon, 15 Jan 2024 16:55:35 +0900
From: Byungchul Park <byungchul@sk.com>
To: Matthew Wilcox <willy@infradead.org>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	kernel_team@skhynix.com, akpm@linux-foundation.org,
	ying.huang@intel.com, namit@vmware.com, xhao@linux.alibaba.com,
	mgorman@techsingularity.net, hughd@google.com, david@redhat.com,
	peterz@infradead.org, luto@kernel.org, tglx@linutronix.de,
	mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com
Subject: Re: [v4 2/3] mm: Defer TLB flush by keeping both src and dst folios
 at migration
Message-ID: <20240115075535.GA56305@system.software.com>
References: <20231109045908.54996-1-byungchul@sk.com>
 <20231109045908.54996-3-byungchul@sk.com>
 <ZUzuUf7JfhybYBgg@casper.infradead.org>
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On Thu, Nov 09, 2023 at 02:36:01PM +0000, Matthew Wilcox wrote:
> On Thu, Nov 09, 2023 at 01:59:07PM +0900, Byungchul Park wrote:
> > +++ b/include/linux/page-flags.h
> > @@ -136,6 +136,7 @@ enum pageflags {
> >  	PG_arch_2,
> >  	PG_arch_3,
> >  #endif
> > +	PG_migrc,		/* Page is under migrc's control */
> >  	__NR_PAGEFLAGS,
> 
> Yeah; no.  We're out of page flags.  And CXL is insufficiently

I won't use an additional page flag any more.

Thanks.
	Byungchul