From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EB0A229A0 for ; Thu, 2 Mar 2023 16:47:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 32C19C433EF; Thu, 2 Mar 2023 16:47:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677775628; bh=Bfaxg0viKwM69JDI9XacTFnWsfSPRHkmBeTe0jCJjhU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uGmuCBI35YMYdj1qVKjiffrckevG0q4jBIGfhm3EB5st05tld1r7r/+8Ufq0To4Vb HnvW2i0wvozPC7dbaBrgO+RLpdgSIaVGLOcrXnrY/sB5ONOar5qnpu3XNZHGz4SugF kxxzQJEePbcEFKG53xu2/J03kt8cXBkzT/RJRSxsgT7eW3dPipwKFHNoMwWvEcHlt/ qmugQgBHieDf/EBVSfDaFKK+GU/QlD1u/QPxlf1drG5mu9noMM5aatTh1cbx0xvpHJ wyKCidm72tG42CB+y/k/m04q9B6PyE7XeLdj3dD4SuXl3uLZfBF9r1tZwPGluZ+n1y j7fDEjh+dmxCg== From: SeongJae Park To: Kefeng Wang Cc: SeongJae Park , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, damon@lists.linux.dev Subject: Re: [PATCH -next] mm/damon/paddr: minor refactor of damon_pa_pageout() Date: Thu, 2 Mar 2023 16:47:06 +0000 Message-Id: <20230302164706.85999-1-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230302144926.40012-1-wangkefeng.wang@huawei.com> References: Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Kefeng, On Thu, 2 Mar 2023 22:49:26 +0800 Kefeng Wang wrote: > Omit two lines by converting if(!folio_isolate_lru()) to > if(folio_isolate_lru()). > > Signed-off-by: Kefeng Wang > --- > mm/damon/paddr.c | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-) > > diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c > index 6c655d9b5639..a557f3c9300f 100644 > --- a/mm/damon/paddr.c > +++ b/mm/damon/paddr.c > @@ -246,14 +246,12 @@ static unsigned long damon_pa_pageout(struct damon_region *r, struct damos *s) > > folio_clear_referenced(folio); > folio_test_clear_young(folio); > - if (!folio_isolate_lru(folio)) { > - folio_put(folio); > - continue; > + if (folio_isolate_lru(folio)) { > + if (folio_test_unevictable(folio)) > + folio_putback_lru(folio); > + else > + list_add(&folio->lru, &folio_list); > } > - if (folio_test_unevictable(folio)) > - folio_putback_lru(folio); > - else > - list_add(&folio->lru, &folio_list); > folio_put(folio); > } This looks ok to me, thank you for your effort! Nevertheless, I don't like increasing depth as much as number of lines. The more-than-3-levels-of-indentation[1] warning is not always right, but this 4 levels of indentation is not making me so exciting. What do you think about adding put_continue label and using it, not only here, but also above part? For example: --- a/mm/damon/paddr.c +++ b/mm/damon/paddr.c @@ -239,21 +239,18 @@ static unsigned long damon_pa_pageout(struct damon_region *r, struct damos *s) if (!folio) continue; - if (damos_pa_filter_out(s, folio)) { - folio_put(folio); - continue; - } + if (damos_pa_filter_out(s, folio)) + goto put_continue; folio_clear_referenced(folio); folio_test_clear_young(folio); - if (!folio_isolate_lru(folio)) { - folio_put(folio); - continue; - } + if (!folio_isolate_lru(folio)) + goto put_continue; if (folio_test_unevictable(folio)) folio_putback_lru(folio); else list_add(&folio->lru, &folio_list); +put_continue: folio_put(folio); } applied = reclaim_pages(&folio_list); It omits three lines. $ git diff --stat mm/damon/paddr.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) [1] https://docs.kernel.org/process/coding-style.html#indentation Thanks, SJ > applied = reclaim_pages(&folio_list); > -- > 2.35.3 > >