From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C96FC04AB2 for ; Thu, 9 May 2019 14:14:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3DDC621479 for ; Thu, 9 May 2019 14:14:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726682AbfEION7 (ORCPT ); Thu, 9 May 2019 10:13:59 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:42478 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726694AbfEIONz (ORCPT ); Thu, 9 May 2019 10:13:55 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 189CF374; Thu, 9 May 2019 07:13:55 -0700 (PDT) Received: from e107155-lin (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8E5C13F238; Thu, 9 May 2019 07:13:52 -0700 (PDT) Date: Thu, 9 May 2019 15:13:50 +0100 From: Sudeep Holla To: Will Deacon Cc: Hanjun Guo , Jeremy Linton , linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, catalin.marinas@arm.com, rjw@rjwysocki.net, lenb@kernel.org, mark.rutland@arm.com, lorenzo.pieralisi@arm.com, linuxarm@huawei.com, john.garry@huawei.com, Hongbo Yao , Alexander Shishkin , Sudeep Holla Subject: Re: [PATCH v3 0/5] arm64: SPE ACPI enablement Message-ID: <20190509141350.GF8239@e107155-lin> References: <20190503232407.37195-1-jeremy.linton@arm.com> <5eaa1607-4bf0-a320-e9cf-2d51eca912c6@huawei.com> <82032e5b-0cb5-e48f-ab51-ba5d5f9dceec@arm.com> <819de863-92ff-51c5-9c35-880db4f6a922@huawei.com> <20190508165149.GB21553@e107155-lin> <20190509092810.GC2667@brain-police> <20190509103559.GB8239@e107155-lin> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190509103559.GB8239@e107155-lin> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Thu, May 09, 2019 at 11:35:59AM +0100, Sudeep Holla wrote: > On Thu, May 09, 2019 at 10:28:11AM +0100, Will Deacon wrote: [...] > > > > Since SPE uses virtual addressing, we don't really care about the underlying > > page layout so there's no need to use higher-order allocations. I suppose we > > could theoretically map them at the pmd level in some cases, but ignoring > > them should also be harmless and I suspect you can delete the check. > > > > Yes, I did a quick look to see if we can do that, but couldn't find a clue. > Not sure if that's any optimisation, we can use order from page_private > and set the values accordingly ? > And I forgot to add the diff that I mentioned above, something like the patch below. Regards, Sudeep -->8 diff --git i/drivers/perf/arm_spe_pmu.c w/drivers/perf/arm_spe_pmu.c index 7cb766dafe85..45cd62517080 100644 --- i/drivers/perf/arm_spe_pmu.c +++ w/drivers/perf/arm_spe_pmu.c @@ -827,7 +827,7 @@ static void arm_spe_pmu_read(struct perf_event *event) static void *arm_spe_pmu_setup_aux(struct perf_event *event, void **pages, int nr_pages, bool snapshot) { - int i, cpu = event->cpu; + int i, j, cpu = event->cpu; struct page **pglist; struct arm_spe_pmu_buf *buf; @@ -859,11 +859,12 @@ static void *arm_spe_pmu_setup_aux(struct perf_event *event, void **pages, struct page *page = virt_to_page(pages[i]); if (PagePrivate(page)) { - pr_warn("unexpected high-order page for auxbuf!"); - goto out_free_pglist; + for (j = 0; j < 1 << page_private(page); j++) + pglist[i + j] = page++; + i += j - 1; + } else { + pglist[i] = page; } - - pglist[i] = virt_to_page(pages[i]); } buf->base = vmap(pglist, nr_pages, VM_MAP, PAGE_KERNEL);