From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4F84B302CB5 for ; Tue, 9 Sep 2025 06:35:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757399704; cv=none; b=XWjATMlS78KtcT3Cu6jMfGopRR9d7W0HLQY5b68qsjjJcpV8g8/T0LTsF0wR2sc7UoYTm+CvniNi9kV5EAI4+5iEKRZ7J0Z07VQFXZ7UdnWFyv11SVKw6e1RJ08DEO47zn0d8Pv3KBPw8gxJSAVAxEuUpE8o+UzqhFxwlX4afog= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757399704; c=relaxed/simple; bh=1uGPKXCMs/UaB1i6RlIm+4ehTkaCjAKIWweeP1WxFYo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=kGqsydzaeLzp1whWOSewEYkHbWueS1NJT+I5ddvFYwYwYs/hy/zxmlzFq+86E8OZMZ2zkKf9I4a1grDqJukkDl9aVLrmQ5vkCBNAiFhTd/T/HRsXlhvI1Dt56//+pw/+m0nGDCct9qsxEWt0jCJk1qdPW7IJYMnCn5k8eVuF27c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 110D315A1; Mon, 8 Sep 2025 23:34:53 -0700 (PDT) Received: from [10.163.72.34] (unknown [10.163.72.34]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B33733F66E; Mon, 8 Sep 2025 23:34:56 -0700 (PDT) Message-ID: Date: Tue, 9 Sep 2025 12:04:52 +0530 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 v3] mm/slub: Refactor note_cmpxchg_failure for better readability To: Ye Liu , Vlastimil Babka , Andrew Morton Cc: Ye Liu , Harry Yoo , Christoph Lameter , David Rientjes , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20250909013307.1093853-1-ye.liu@linux.dev> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20250909013307.1093853-1-ye.liu@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 09/09/25 7:03 AM, Ye Liu wrote: > From: Ye Liu > > Use IS_ENABLED() and standard if-else to make the code clearer. > > Signed-off-by: Ye Liu > Reviewed-by: Harry Yoo > Reviewed-by: Christoph Lameter (Ampere) > > --- > Changes in v3: > - Add "---" in front of the change log. > Changes in v2: > - Insert newline after && as it's more than 80 columns. > --- > mm/slub.c | 11 +++++------ > 1 file changed, 5 insertions(+), 6 deletions(-) > > diff --git a/mm/slub.c b/mm/slub.c > index 30003763d224..5711d6d29a3f 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -3064,18 +3064,17 @@ static inline void note_cmpxchg_failure(const char *n, > > pr_info("%s %s: cmpxchg redo ", n, s->name); > > -#ifdef CONFIG_PREEMPTION > - if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) > + if (IS_ENABLED(CONFIG_PREEMPTION) && > + tid_to_cpu(tid) != tid_to_cpu(actual_tid)) { > pr_warn("due to cpu change %d -> %d\n", > tid_to_cpu(tid), tid_to_cpu(actual_tid)); > - else > -#endif > - if (tid_to_event(tid) != tid_to_event(actual_tid)) > + } else if (tid_to_event(tid) != tid_to_event(actual_tid)) { > pr_warn("due to cpu running other code. Event %ld->%ld\n", > tid_to_event(tid), tid_to_event(actual_tid)); > - else > + } else { > pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", > actual_tid, tid, next_tid(tid)); > + } > #endif > stat(s, CMPXCHG_DOUBLE_CPU_FAIL); > } Reviewed-by: Anshuman Khandual