From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) (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 E82B41A00EC for ; Thu, 15 Aug 2024 14:40:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.191 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723732859; cv=none; b=duu5rryydAGRnm7/MNe1fb9aBCIwjDEUkggcX6RIt4s45EVo+Pd8fcUxzYYufPdAYDEGaBV1XVBGQ9RdW++mQmthsYQLVplrdLpjO6WC1Gdp6B4+5kP5ADgssqthYlcN15w7ayC4O/iTJUVffz6NnwRS9ie7Jh9eLH5IiwA96pA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723732859; c=relaxed/simple; bh=Z8Ci4B33S4Of5MZbBVTn4FekWSzm5eG/tF6KeDmLPrQ=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=BBLeReqN0fCoyx3EDUzvQVt/8G/L2zw2ZoagRCaqSBRUN/PqEOzYEjw0mmMYAGEUIjC3+HnQDVoOieUVH8PSmPv9xgCEP9SHW27KErLdd4zsZ0VzfcnIf0QvJp7tgQSzLX56u4dFBiFPVvSqu5w8Zq/O0SRI/AfebDm8H9t84qc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.191 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4Wl7570YPHz1HG8l; Thu, 15 Aug 2024 22:37:47 +0800 (CST) Received: from dggpemf100008.china.huawei.com (unknown [7.185.36.138]) by mail.maildlp.com (Postfix) with ESMTPS id B53FA1A016C; Thu, 15 Aug 2024 22:40:52 +0800 (CST) Received: from [10.174.177.243] (10.174.177.243) by dggpemf100008.china.huawei.com (7.185.36.138) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Thu, 15 Aug 2024 22:40:52 +0800 Message-ID: <6d19d790-92d2-40f9-9797-cc08bf3921fe@huawei.com> Date: Thu, 15 Aug 2024 22:40:51 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH mm-unstable v1 2/3] mm/cma: add cma_alloc_folio() Content-Language: en-US To: Yu Zhao , Andrew Morton , Muchun Song CC: "Matthew Wilcox (Oracle)" , Zi Yan , , References: <20240811212129.3074314-1-yuzhao@google.com> <20240811212129.3074314-3-yuzhao@google.com> From: Kefeng Wang In-Reply-To: <20240811212129.3074314-3-yuzhao@google.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemf100008.china.huawei.com (7.185.36.138) On 2024/8/12 5:21, Yu Zhao wrote: > With alloc_contig_range() and free_contig_range() supporting large > folios, CMA can allocate and free large folios too, by > cma_alloc_folio() and cma_release(). > > Signed-off-by: Yu Zhao > --- > include/linux/cma.h | 1 + > mm/cma.c | 47 ++++++++++++++++++++++++++++++--------------- > 2 files changed, 33 insertions(+), 15 deletions(-) > > diff --git a/include/linux/cma.h b/include/linux/cma.h > index 9db877506ea8..086553fbda73 100644 > --- a/include/linux/cma.h > +++ b/include/linux/cma.h > @@ -46,6 +46,7 @@ extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, > struct cma **res_cma); > extern struct page *cma_alloc(struct cma *cma, unsigned long count, unsigned int align, > bool no_warn); > +extern struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp); > extern bool cma_pages_valid(struct cma *cma, const struct page *pages, unsigned long count); > extern bool cma_release(struct cma *cma, const struct page *pages, unsigned long count); > > diff --git a/mm/cma.c b/mm/cma.c > index 95d6950e177b..46feb06db8e7 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -403,18 +403,8 @@ static void cma_debug_show_areas(struct cma *cma) > spin_unlock_irq(&cma->lock); > } > > -/** > - * cma_alloc() - allocate pages from contiguous area > - * @cma: Contiguous memory region for which the allocation is performed. > - * @count: Requested number of pages. > - * @align: Requested alignment of pages (in PAGE_SIZE order). > - * @no_warn: Avoid printing message about failed allocation > - * > - * This function allocates part of contiguous memory on specific > - * contiguous memory area. > - */ > -struct page *cma_alloc(struct cma *cma, unsigned long count, > - unsigned int align, bool no_warn) > +static struct page *__cma_alloc(struct cma *cma, unsigned long count, > + unsigned int align, gfp_t gfp) > { > unsigned long mask, offset; > unsigned long pfn = -1; > @@ -463,8 +453,7 @@ struct page *cma_alloc(struct cma *cma, unsigned long count, > > pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); > mutex_lock(&cma_mutex); > - ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, > - GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0)); > + ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, gfp); > mutex_unlock(&cma_mutex); > if (ret == 0) { > page = pfn_to_page(pfn); > @@ -494,7 +483,7 @@ struct page *cma_alloc(struct cma *cma, unsigned long count, > page_kasan_tag_reset(nth_page(page, i)); > } > > - if (ret && !no_warn) { > + if (ret && !(gfp & __GFP_NOWARN)) { > pr_err_ratelimited("%s: %s: alloc failed, req-size: %lu pages, ret: %d\n", > __func__, cma->name, count, ret); > cma_debug_show_areas(cma); > @@ -513,6 +502,34 @@ struct page *cma_alloc(struct cma *cma, unsigned long count, > return page; > } > > +/** > + * cma_alloc() - allocate pages from contiguous area > + * @cma: Contiguous memory region for which the allocation is performed. > + * @count: Requested number of pages. > + * @align: Requested alignment of pages (in PAGE_SIZE order). > + * @no_warn: Avoid printing message about failed allocation > + * > + * This function allocates part of contiguous memory on specific > + * contiguous memory area. > + */ > +struct page *cma_alloc(struct cma *cma, unsigned long count, > + unsigned int align, bool no_warn) > +{ > + return __cma_alloc(cma, count, align, GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0)); > +} > + > +struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp) > +{ > + struct page *page; > + > + if (WARN_ON(order && !(gfp | __GFP_COMP))) > + return NULL; > + > + page = __cma_alloc(cma, 1 << order, order, gfp); > + > + return page ? page_folio(page) : NULL; We don't set large_rmappable for cma alloc folio, which is not consistent with other folio allocation, eg folio_alloc/folio_alloc_mpol(), there is no issue for HugeTLB folio, and for HugeTLB folio must without large_rmappable, but once we use it for mTHP/THP, it need some extra handle, maybe we set large_rmappable here, and clear it in init_new_hugetlb_folio()? > +} > + > bool cma_pages_valid(struct cma *cma, const struct page *pages, > unsigned long count) > {