Date:   Tue, 14 Mar 2023 07:25:54 +0000
From:   Hyeonggon Yoo <42.hyeyoo@gmail.com>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Christoph Lameter <cl@linux.com>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Pekka Enberg <penberg@kernel.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        rcu@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, patches@lists.linux.dev,
        netdev@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH 3/7] mm, page_flags: remove PG_slob_free
Message-ID: <ZBAhgpY1KSE3FwAv@localhost>
References: <20230310103210.22372-1-vbabka@suse.cz>
 <20230310103210.22372-4-vbabka@suse.cz>
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On Fri, Mar 10, 2023 at 11:32:05AM +0100, Vlastimil Babka wrote:
> With SLOB removed we no longer need the PG_slob_free alias for
> PG_private. Also update tools/mm/page-types.
> 
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
> ---
>  include/linux/page-flags.h | 4 ----
>  tools/mm/page-types.c      | 6 +-----
>  2 files changed, 1 insertion(+), 9 deletions(-)
> 
> diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
> index a7e3a3405520..2bdc41cb0594 100644
> --- a/include/linux/page-flags.h
> +++ b/include/linux/page-flags.h
> @@ -174,9 +174,6 @@ enum pageflags {
>  	/* Remapped by swiotlb-xen. */
>  	PG_xen_remapped = PG_owner_priv_1,
>  
> -	/* SLOB */
> -	PG_slob_free = PG_private,
> -
>  #ifdef CONFIG_MEMORY_FAILURE
>  	/*
>  	 * Compound pages. Stored in first tail page's flags.
> @@ -483,7 +480,6 @@ PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD)
>  PAGEFLAG(Workingset, workingset, PF_HEAD)
>  	TESTCLEARFLAG(Workingset, workingset, PF_HEAD)
>  __PAGEFLAG(Slab, slab, PF_NO_TAIL)
> -__PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL)
>  PAGEFLAG(Checked, checked, PF_NO_COMPOUND)	   /* Used by some filesystems */
>  
>  /* Xen */
> diff --git a/tools/mm/page-types.c b/tools/mm/page-types.c
> index 381dcc00cb62..8d5595b6c59f 100644
> --- a/tools/mm/page-types.c
> +++ b/tools/mm/page-types.c
> @@ -85,7 +85,6 @@
>   */
>  #define KPF_ANON_EXCLUSIVE	47
>  #define KPF_READAHEAD		48
> -#define KPF_SLOB_FREE		49
>  #define KPF_SLUB_FROZEN		50
>  #define KPF_SLUB_DEBUG		51
>  #define KPF_FILE		61
> @@ -141,7 +140,6 @@ static const char * const page_flag_names[] = {
>  
>  	[KPF_ANON_EXCLUSIVE]	= "d:anon_exclusive",
>  	[KPF_READAHEAD]		= "I:readahead",
> -	[KPF_SLOB_FREE]		= "P:slob_free",
>  	[KPF_SLUB_FROZEN]	= "A:slub_frozen",
>  	[KPF_SLUB_DEBUG]	= "E:slub_debug",
>  
> @@ -478,10 +476,8 @@ static uint64_t expand_overloaded_flags(uint64_t flags, uint64_t pme)
>  	if ((flags & BIT(ANON)) && (flags & BIT(MAPPEDTODISK)))
>  		flags ^= BIT(MAPPEDTODISK) | BIT(ANON_EXCLUSIVE);
>  
> -	/* SLOB/SLUB overload several page flags */
> +	/* SLUB overloads several page flags */
>  	if (flags & BIT(SLAB)) {
> -		if (flags & BIT(PRIVATE))
> -			flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
>  		if (flags & BIT(ACTIVE))
>  			flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
>  		if (flags & BIT(ERROR))
> -- 
> 2.39.2

Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>