All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Huang\, Ying" <ying.huang@intel.com>
To: <minchan@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	lkml <linux-kernel@vger.kernel.org>,
	linux-mm <linux-mm@kvack.org>, Hugh Dickins <hughd@google.com>
Subject: Re: [PATCH RESEND 1/2] mm: swap: clean up swap readahead
Date: Fri, 23 Feb 2018 16:02:27 +0800	[thread overview]
Message-ID: <874lm83zho.fsf@yhuang-dev.intel.com> (raw)
In-Reply-To: <20180220085249.151400-2-minchan@kernel.org> (minchan@kernel.org's message of "Tue, 20 Feb 2018 17:52:48 +0900")

<minchan@kernel.org> writes:
[snip]

> diff --git a/mm/swap_state.c b/mm/swap_state.c
> index 39ae7cfad90f..c56cce64b2c3 100644
> --- a/mm/swap_state.c
> +++ b/mm/swap_state.c
> @@ -332,32 +332,38 @@ struct page *lookup_swap_cache(swp_entry_t entry, struct vm_area_struct *vma,
>  			       unsigned long addr)
>  {
>  	struct page *page;
> -	unsigned long ra_info;
> -	int win, hits, readahead;
>  
>  	page = find_get_page(swap_address_space(entry), swp_offset(entry));
>  
>  	INC_CACHE_INFO(find_total);
>  	if (page) {
> +		bool vma_ra = swap_use_vma_readahead();
> +		bool readahead = TestClearPageReadahead(page);
> +

TestClearPageReadahead() cannot be called for compound page.  As in

PAGEFLAG(Readahead, reclaim, PF_NO_COMPOUND)
	TESTCLEARFLAG(Readahead, reclaim, PF_NO_COMPOUND)

>  		INC_CACHE_INFO(find_success);
>  		if (unlikely(PageTransCompound(page)))
>  			return page;
> -		readahead = TestClearPageReadahead(page);

So we can only call it here after checking whether page is compound.

Best Regards,
Huang, Ying

> -		if (vma) {
> -			ra_info = GET_SWAP_RA_VAL(vma);
> -			win = SWAP_RA_WIN(ra_info);
> -			hits = SWAP_RA_HITS(ra_info);
> +
> +		if (vma && vma_ra) {
> +			unsigned long ra_val;
> +			int win, hits;
> +
> +			ra_val = GET_SWAP_RA_VAL(vma);
> +			win = SWAP_RA_WIN(ra_val);
> +			hits = SWAP_RA_HITS(ra_val);
>  			if (readahead)
>  				hits = min_t(int, hits + 1, SWAP_RA_HITS_MAX);
>  			atomic_long_set(&vma->swap_readahead_info,
>  					SWAP_RA_VAL(addr, win, hits));
>  		}
> +
>  		if (readahead) {
>  			count_vm_event(SWAP_RA_HIT);
> -			if (!vma)
> +			if (!vma || !vma_ra)
>  				atomic_inc(&swapin_readahead_hits);
>  		}
>  	}
> +
>  	return page;
>  }
>

[snip]

WARNING: multiple messages have this Message-ID (diff)
From: "Huang\, Ying" <ying.huang@intel.com>
To: minchan@kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>,
	lkml <linux-kernel@vger.kernel.org>,
	linux-mm <linux-mm@kvack.org>, Hugh Dickins <hughd@google.com>
Subject: Re: [PATCH RESEND 1/2] mm: swap: clean up swap readahead
Date: Fri, 23 Feb 2018 16:02:27 +0800	[thread overview]
Message-ID: <874lm83zho.fsf@yhuang-dev.intel.com> (raw)
In-Reply-To: <20180220085249.151400-2-minchan@kernel.org> (minchan@kernel.org's message of "Tue, 20 Feb 2018 17:52:48 +0900")

<minchan@kernel.org> writes:
[snip]

> diff --git a/mm/swap_state.c b/mm/swap_state.c
> index 39ae7cfad90f..c56cce64b2c3 100644
> --- a/mm/swap_state.c
> +++ b/mm/swap_state.c
> @@ -332,32 +332,38 @@ struct page *lookup_swap_cache(swp_entry_t entry, struct vm_area_struct *vma,
>  			       unsigned long addr)
>  {
>  	struct page *page;
> -	unsigned long ra_info;
> -	int win, hits, readahead;
>  
>  	page = find_get_page(swap_address_space(entry), swp_offset(entry));
>  
>  	INC_CACHE_INFO(find_total);
>  	if (page) {
> +		bool vma_ra = swap_use_vma_readahead();
> +		bool readahead = TestClearPageReadahead(page);
> +

TestClearPageReadahead() cannot be called for compound page.  As in

PAGEFLAG(Readahead, reclaim, PF_NO_COMPOUND)
	TESTCLEARFLAG(Readahead, reclaim, PF_NO_COMPOUND)

>  		INC_CACHE_INFO(find_success);
>  		if (unlikely(PageTransCompound(page)))
>  			return page;
> -		readahead = TestClearPageReadahead(page);

So we can only call it here after checking whether page is compound.

Best Regards,
Huang, Ying

> -		if (vma) {
> -			ra_info = GET_SWAP_RA_VAL(vma);
> -			win = SWAP_RA_WIN(ra_info);
> -			hits = SWAP_RA_HITS(ra_info);
> +
> +		if (vma && vma_ra) {
> +			unsigned long ra_val;
> +			int win, hits;
> +
> +			ra_val = GET_SWAP_RA_VAL(vma);
> +			win = SWAP_RA_WIN(ra_val);
> +			hits = SWAP_RA_HITS(ra_val);
>  			if (readahead)
>  				hits = min_t(int, hits + 1, SWAP_RA_HITS_MAX);
>  			atomic_long_set(&vma->swap_readahead_info,
>  					SWAP_RA_VAL(addr, win, hits));
>  		}
> +
>  		if (readahead) {
>  			count_vm_event(SWAP_RA_HIT);
> -			if (!vma)
> +			if (!vma || !vma_ra)
>  				atomic_inc(&swapin_readahead_hits);
>  		}
>  	}
> +
>  	return page;
>  }
>

[snip]

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2018-02-23  8:02 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-20  8:52 [PATCH RESEND 0/2] swap readahead clean up minchan
2018-02-20  8:52 ` minchan
2018-02-20  8:52 ` [PATCH RESEND 1/2] mm: swap: clean up swap readahead minchan
2018-02-20  8:52   ` minchan
2018-02-23  8:02   ` Huang, Ying [this message]
2018-02-23  8:02     ` Huang, Ying
2018-02-26  4:56     ` Minchan Kim
2018-02-26  4:56       ` Minchan Kim
2018-02-26  5:18       ` Huang, Ying
2018-02-26  5:18         ` Huang, Ying
2018-02-26  5:41         ` Minchan Kim
2018-02-26  5:41           ` Minchan Kim
2018-02-26  8:22           ` Huang, Ying
2018-02-26  8:22             ` Huang, Ying
2018-02-20  8:52 ` [PATCH RESEND 2/2] mm: swap: unify cluster-based and vma-based " minchan
2018-02-20  8:52   ` minchan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=874lm83zho.fsf@yhuang-dev.intel.com \
    --to=ying.huang@intel.com \
    --cc=akpm@linux-foundation.org \
    --cc=hughd@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=minchan@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.