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Date:   Tue, 22 Nov 2022 15:35:18 +0900
From:   Sergey Senozhatsky <senozhatsky@chromium.org>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Sergey Senozhatsky <senozhatsky@chromium.org>,
        Nhat Pham <nphamcs@gmail.com>, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        minchan@kernel.org, ngupta@vflare.org, sjenning@redhat.com,
        ddstreet@ieee.org, vitaly.wool@konsulko.com
Subject: Re: [PATCH v6 6/6] zsmalloc: Implement writeback mechanism for
 zsmalloc
Message-ID: <Y3xtpoQpb8DuiTlh@google.com>
References: <20221119001536.2086599-1-nphamcs@gmail.com>
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 <Y3w+C8ClzP6VbqrA@cmpxchg.org>
 <Y3xFHIgkiZNYCbHi@google.com>
 <Y3xnf7pR4vI7o9PV@cmpxchg.org>
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On (22/11/22 01:09), Johannes Weiner wrote:
> On Tue, Nov 22, 2022 at 12:42:20PM +0900, Sergey Senozhatsky wrote:
> > On (22/11/21 22:12), Johannes Weiner wrote:
> > > On Tue, Nov 22, 2022 at 11:15:20AM +0900, Sergey Senozhatsky wrote:
> > > > On (22/11/18 16:15), Nhat Pham wrote:

[..]

> > What I meant was: if zs_reclaim_page() makes only partial progress
> > with the current LRU tail zspage and returns -EAGAIN, then we just
> > don't increment `total` and continue looping in zs_zpool_shrink().
> 
> Hm, but it breaks on -EAGAIN, it doesn't continue.

Yes. "What if it would continue". Would it make sense to not
break on EAGAIN?

	while (total < pages) {
		ret = zs_reclaim_page(pool);
		if (ret == -EAGAIN)
			continue;
		if (ret < 0)
			break;
		total++;
	}

Then we don't need retry loop in zs_reclaim_page().