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 32F561E2317 for ; Thu, 10 Oct 2024 21:17:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728595048; cv=none; b=Yq032K8J908F76UioW7IjkrwxOjUaJspPUW5+yUWrRLWpgWPITpb8OQQzmDB67a1EhmxPxz1EC2GUqomvWzhE0EicpQcAmTxsLQoQqKNr+2NirIGmNO1qbs2pHVJbmY4yvm5W/BXiQ3z3z6e4vFTtPWCfC+NHqfTE7rFOV1P0ic= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728595048; c=relaxed/simple; bh=h/ydTxkvMIlJ33x8vbPMvRfe6S+g8mbXshs+rjB07HA=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=Sf75A4EXz9x9bkPrzGpz3Hyye9Y9wPio6Zgk3VRAJj7H97thnwLkNEQw6E+quvhbN2MVKgmhx8OvAeAfU1xMwdT9+Amqg4ykDCQcYKDd/o3YAL4CbJuMWtv4arUNTWg09cpPFezaYdSZ6anHfVQGMuzWtaQeZn452GMtFlMZteU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=u+N6SE9K; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="u+N6SE9K" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D5E3C4CEC5; Thu, 10 Oct 2024 21:17:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1728595047; bh=h/ydTxkvMIlJ33x8vbPMvRfe6S+g8mbXshs+rjB07HA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=u+N6SE9KV1DUPMTlYZr52oPJT95+GVQ+9eMki630RwTp8kd6oyeSyx7OYwJdTo+/J efQmV5A3cfJNTaGTPx28R5XhtznQN8gDcMin5sT135VEZovhQ35XSprj5QAHr29wLu C2B6DgmtdPUKMvcKW2kCTxZojIrUW6shfV3sSR4k= Date: Thu, 10 Oct 2024 14:17:26 -0700 From: Andrew Morton To: =?UTF-8?B?6auY57+U?= Cc: Frank van der Linden , David Hildenbrand , Xiang Gao , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: =?UTF-8?B?562U5aSNOiDlm57lpI06?= [External Mail]Re: [PATCH v2] mm/cma: print total and used count in cma_alloc() Message-Id: <20241010141726.0bc7b9d0758756249efadc3a@linux-foundation.org> In-Reply-To: <5de41e1999414426ba88447a4d95db18@xiaomi.com> References: <20240929032757.404707-1-gxxa03070307@gmail.com> <2a7b7fc3a48d4bb9a6394e51af074017@xiaomi.com> <20241004153947.43c5b16b7f75b0f60e918019@linux-foundation.org> <5de41e1999414426ba88447a4d95db18@xiaomi.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On Thu, 10 Oct 2024 08:48:55 +0000 高翔 wrote: > > ________________________________ > 发件人: Frank van der Linden > 发送时间: 2024年10月5日 6:55 > 收件人: Andrew Morton > 抄送: 高翔; David Hildenbrand; Xiang Gao; linux-mm@kvack.org; linux-kernel@vger.kernel.org > 主题: Re: 回复: [External Mail]Re: [PATCH v2] mm/cma: print total and used count in cma_alloc() > > [外部邮件] 此邮件来源于小米公司外部，请谨慎处理。若对邮件安全性存疑，请将邮件转发给misec@xiaomi.com进行反馈 > > On Fri, Oct 4, 2024 at 3:39 PM Andrew Morton wrote: > > > > On Fri, 4 Oct 2024 12:23:30 +0000 高翔 wrote: > > > > > > > +static unsigned long cma_get_used_pages(struct cma *cma) { > > > > > + unsigned long used; > > > > > + > > > > > + spin_lock_irq(&cma->lock); > > > > > + used = bitmap_weight(cma->bitmap, (int)cma_bitmap_maxno(cma)); > > > > > + spin_unlock_irq(&cma->lock); > > > > > > > > This adds overhead to each allocation, even if debug outputs are > > > > ignored I assume? > > > > > > > > I wonder if we'd want to print these details only when our allocation > > > > failed? > > > > > > > > Alternatively, we could actually track how many pages are allocated in > > > > the cma, so we don't have to traverse the complete bitmap on every > > > > allocation. > > > > > > > > > > Yep, that's what I did as part of > > > https://lore.kernel.org/all/20240724124845.614c03ad39f8af3729cebee6@linux-foundation.org/T/ > > > > > > That patch didn't make it in (yet). I'm happy for it to be combined with this one if that's easier. > > > > That patch has been forgotten about. As I asked in July, > > "I suggest a resend, and add some Cc:s for likely reviewers." > > > Indeed - I certainly wasn't suggesting that anyone else forgot about > > it, it's up to me to follow up here, and I haven't yet. > > > Do I need to resend it after adding "used_count" member to the "struct cma" as V3? I don't know what is being asked here. What is this used_count? Some other patch, presumably? Which? The preferable thing to do is to send a patch against latest mm-unstable or linux-next.