From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f42.google.com (mail-pa0-f42.google.com [209.85.220.42]) by kanga.kvack.org (Postfix) with ESMTP id 3F1236B0035 for ; Mon, 21 Jul 2014 18:00:55 -0400 (EDT) Received: by mail-pa0-f42.google.com with SMTP id lf10so10682531pab.1 for ; Mon, 21 Jul 2014 15:00:54 -0700 (PDT) Received: from smtp.codeaurora.org (smtp.codeaurora.org. [198.145.11.231]) by mx.google.com with ESMTPS id ro10si7789816pbc.207.2014.07.21.15.00.53 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 21 Jul 2014 15:00:54 -0700 (PDT) Message-ID: <53CD8D94.9060207@codeaurora.org> Date: Mon, 21 Jul 2014 15:00:52 -0700 From: Laura Abbott MIME-Version: 1.0 Subject: Re: [PATCHv4 5/5] arm64: Add atomic pool for non-coherent and CMA allocations. References: <1404324218-4743-1-git-send-email-lauraa@codeaurora.org> <1404324218-4743-6-git-send-email-lauraa@codeaurora.org> <20140704133517.GA9860@ulmo> In-Reply-To: <20140704133517.GA9860@ulmo> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Thierry Reding Cc: Will Deacon , Catalin Marinas , David Riley , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ritesh Harjain , linux-arm-kernel@lists.infradead.org On 7/4/2014 6:35 AM, Thierry Reding wrote: > On Wed, Jul 02, 2014 at 11:03:38AM -0700, Laura Abbott wrote: > [...] >> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c > [...] >> +static struct gen_pool *atomic_pool; >> + >> +#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K >> +static size_t atomic_pool_size = DEFAULT_DMA_COHERENT_POOL_SIZE; > > There doesn't seem to be much use for this since it can't be overridden > via init_dma_coherent_pool_size like on ARM. > There is still the command line option coherent_pool= though [...] >> + if (page) { >> + int ret; >> + >> + atomic_pool = gen_pool_create(PAGE_SHIFT, -1); >> + if (!atomic_pool) >> + goto free_page; >> + >> + addr = dma_common_contiguous_remap(page, atomic_pool_size, >> + VM_USERMAP, prot, atomic_pool_init); >> + >> + if (!addr) >> + goto destroy_genpool; >> + >> + memset(addr, 0, atomic_pool_size); >> + __dma_flush_range(addr, addr + atomic_pool_size); >> + >> + ret = gen_pool_add_virt(atomic_pool, (unsigned long)addr, >> + page_to_phys(page), >> + atomic_pool_size, -1); >> + if (ret) >> + goto remove_mapping; >> + >> + gen_pool_set_algo(atomic_pool, >> + gen_pool_first_fit_order_align, NULL); >> + >> + pr_info("DMA: preallocated %zd KiB pool for atomic allocations\n", > > I think this should be "%zu" because atomic_pool_size is a size_t, not a > ssize_t. > Yes, will fix. >> + atomic_pool_size / 1024); >> + return 0; >> + } >> + goto out; >> + >> +remove_mapping: >> + dma_common_free_remap(addr, atomic_pool_size, VM_USERMAP); >> +destroy_genpool: >> + gen_pool_destroy(atomic_pool); >> + atomic_pool == NULL; > > This probably doesn't belong here. > Dastardly typo. >> +free_page: >> + if (!dma_release_from_contiguous(NULL, page, nr_pages)) >> + __free_pages(page, get_order(atomic_pool_size)); > > You use get_order(atomic_pool_size) a lot, perhaps it should be a > temporary variable? > Yes, three usages is probably enough. >> +out: >> + pr_err("DMA: failed to allocate %zx KiB pool for atomic coherent allocation\n", >> + atomic_pool_size / 1024); > > Print in decimal rather than hexadecimal? > I actually prefer hexadecimal but I should at least be consistent between error and non-error paths. > Thierry > Thanks, Laura -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- 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: email@kvack.org