From nobody Mon Apr 6 21:24:51 2026 Received: from va-1-113.ptr.blmpb.com (va-1-113.ptr.blmpb.com [209.127.230.113]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3E89A2EA16A for ; Wed, 18 Mar 2026 04:57:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.127.230.113 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773809869; cv=none; b=j76hZuMw+vZg/FXSaDCmKpdX47XoWYXB66HD+h5WOrxOQx0ntlEyNyhb8B2bZvDMAgxfJzqMFFw3tqdItNpCdr/SBet8ALYkkaMpR6cHahXqrETfXIp0HCeBKhWXtslmUlIJ7QqSIY7eAL4VGZVVZmgWG5DC34iDvOX6o1+Pa2E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773809869; c=relaxed/simple; bh=XH+TgyQJYrU8fNK1eEXW2c0NoIumPBqw2CKhw534Sz4=; h=To:Cc:Date:Message-Id:Mime-Version:References:Content-Type:From: Subject:In-Reply-To; b=bc9IWimI6xkL0jJHv3IdQ+HV0HeED4T4DbCCCVUvznbz9iAe2PS5WVEIWmCsTSwVQwq+hi6MHNBGlonoUUEoK03X/AI0btOovlymcoQJBmV8dNX1a6KdaTwvJJEC3TC3JSY6HEUIGlJ1ykJrQNnr4KJbaUqjrtAyVGbrR6rQbpk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=bytedance.com; spf=pass smtp.mailfrom=bytedance.com; dkim=pass (2048-bit key) header.d=bytedance.com header.i=@bytedance.com header.b=eRQ2uZoH; arc=none smtp.client-ip=209.127.230.113 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=bytedance.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bytedance.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bytedance.com header.i=@bytedance.com header.b="eRQ2uZoH" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=2212171451; d=bytedance.com; t=1773809862; h=from:subject: mime-version:from:date:message-id:subject:to:cc:reply-to:content-type: mime-version:in-reply-to:message-id; bh=XJQbGVgOA6I60dB8y0qr6QT4Xv7obtiE15uJEm45WXA=; b=eRQ2uZoHlwCDtzXiAa9UJwu+NCK4oQZdEwYZ38qyffg7YNqWKzOpvvh+1JgQQE809pmyS8 znC0862odMBCQhzeu3nfUIdxtVKB1Uwdk2vkjCeJOvnnwMIEdNYVZAanSixm2/m+B0bCkN /3iyXIVuFt6gopmGNloafnUMZVj+uJ17ZdJktmzKRWR5BSFzehuWuyLKIFhMjN9GBV+Rpa Ajp8N2NUb4pCjAUDuY8ZuXp3bmo8MtlM0W2RVYH0/1uSW9CppTqAUVqaxQ9efWcKVgLBPA 2pxNRx3UJ03DnnpgcWfILYZ7+JGp6QZtzelTRmLx//jAt5eYcwfCpQrBPyX/dw== X-Original-From: Chuyi Zhou To: , , , , , , , , , , , Cc: , "Chuyi Zhou" Date: Wed, 18 Mar 2026 12:56:27 +0800 Message-Id: <20260318045638.1572777-2-zhouchuyi@bytedance.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260318045638.1572777-1-zhouchuyi@bytedance.com> Content-Transfer-Encoding: quoted-printable From: "Chuyi Zhou" Subject: [PATCH v3 01/12] smp: Disable preemption explicitly in __csd_lock_wait X-Mailer: git-send-email 2.20.1 In-Reply-To: <20260318045638.1572777-1-zhouchuyi@bytedance.com> X-Lms-Return-Path: Content-Type: text/plain; charset="utf-8" The latter patches will enable preemption before csd_lock_wait(), which could break csdlock_debug. Because the slice of other tasks on the CPU may be accounted between ktime_get_mono_fast_ns() calls. Disable preemption explicitly in __csd_lock_wait(). This is a preparation for the next patches. Signed-off-by: Chuyi Zhou Acked-by: Muchun Song Reviewed-by: Steven Rostedt (Google) --- kernel/smp.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/smp.c b/kernel/smp.c index f349960f79ca..fc1f7a964616 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -323,6 +323,8 @@ static void __csd_lock_wait(call_single_data_t *csd) int bug_id =3D 0; u64 ts0, ts1; =20 + guard(preempt)(); + ts1 =3D ts0 =3D ktime_get_mono_fast_ns(); for (;;) { if (csd_lock_wait_toolong(csd, ts0, &ts1, &bug_id, &nmessages)) --=20 2.20.1