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 8ECF863C8 for ; Tue, 27 Dec 2022 19:42:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9B9CEC433EF; Tue, 27 Dec 2022 19:42:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672170179; bh=ndjXj2bFtuxWHzxqZ4f5g2WLfiRgnsCCho8XX+smju4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CL7Y/uW0ufuRhI2qSL8vBNIinxHyVNaX2ReqyuVJ7ofv6RHJY7pKJ4aBVc3gKYeaW eV1XrvbEvYdCZpNYN3bfvA34ofWB2egHg5uXobavgpja2mNIz0CcUmn6QDtdcdI7Lb CwZjj69zHX47/kuBe40TpHopBsCBSDbroU+eyeL4YqgvCNQnJtmM/iEk8GmopFksW9 0w4T9W1TGmqtmElNip/rWadXJYYWYzx8pUGj8wPNati6RcUoFILZKTHcn//0f2QYab XY9b4LfdXlmHx3bGmP0Fz+4W40mhOatzSHGn9lp3zdtg7MaYOLqa9RUXgRpcG/pF6j D3a1bC0K7Yh/w== From: SeongJae Park To: Kefeng Wang Cc: Andrew Morton , SeongJae Park , damon@lists.linux.dev, linux-mm@kvack.org, vishal.moola@gmail.com, willy@infradead.org, david@redhat.com Subject: Re: [PATCH -next v2 2/7] mm: damon: introduce damon_get_folio() Date: Tue, 27 Dec 2022 19:42:57 +0000 Message-Id: <20221227194257.2744-1-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221227122714.161224-3-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, Could we use 'mm/damon:' prefix instead of 'mm: damon:' for the patch subjects? On Tue, 27 Dec 2022 20:27:09 +0800 Kefeng Wang wrote: > Introduce damon_get_folio(), and the temporary wrapper function > damon_get_page(), which help us to convert damon related function > to use folios, and it will be droped once the conversion is completed. > > Signed-off-by: Kefeng Wang > --- > mm/damon/ops-common.c | 14 ++++++++------ > mm/damon/ops-common.h | 8 +++++++- > 2 files changed, 15 insertions(+), 7 deletions(-) > > diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c > index 75409601f934..ff38a19aa92e 100644 > --- a/mm/damon/ops-common.c > +++ b/mm/damon/ops-common.c > @@ -16,21 +16,23 @@ > * Get an online page for a pfn if it's in the LRU list. Otherwise, returns > * NULL. > * > - * The body of this function is stolen from the 'page_idle_get_page()'. We > + * The body of this function is stolen from the 'page_idle_get_folio()'. We > * steal rather than reuse it because the code is quite simple. > */ > -struct page *damon_get_page(unsigned long pfn) > +struct folio *damon_get_folio(unsigned long pfn) > { > struct page *page = pfn_to_online_page(pfn); > + struct folio *folio; > > if (!page || !PageLRU(page) || !get_page_unless_zero(page)) > return NULL; > > - if (unlikely(!PageLRU(page))) { > - put_page(page); > - page = NULL; > + folio = page_folio(page); > + if (unlikely(!folio_test_lru(folio))) { > + folio_put(folio); > + folio = NULL; > } I think Matthew's comment for 'page_idle_get_folio()'[1] could applied here? [1] https://lore.kernel.org/damon/Y6s2HPjrON2Sx%2Fgr@casper.infradead.org/ > - return page; > + return folio; > } > > void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr) > diff --git a/mm/damon/ops-common.h b/mm/damon/ops-common.h > index 8d82d3722204..4ee607813981 100644 > --- a/mm/damon/ops-common.h > +++ b/mm/damon/ops-common.h > @@ -7,7 +7,13 @@ > > #include > > -struct page *damon_get_page(unsigned long pfn); > +struct folio *damon_get_folio(unsigned long pfn); > +static inline struct page *damon_get_page(unsigned long pfn) > +{ > + struct folio *folio = damon_get_folio(pfn); > + > + return &folio->page; I think we should check if folio is NULL before dereferencing it? > +} > > void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr); > void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm, unsigned long addr); > -- > 2.35.3 >