From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (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 643C611187 for ; Fri, 10 Jan 2025 00:24:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736468676; cv=none; b=qJLMQ1pfXPX2SB+9ylIU6pO4PYiAMMzgoQl6JZAktb1R0uz81X/rCQ3nXQROJakbF4h7vUSMaPwRUXorPnaD2HBhL6neUoEvwPwKDJosOWRh9GApOzFK9+d7FBV+XzjfguFvswlnIz/N4HzeDsRPIw8QukdAruGeBS/KV7GGahQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736468676; c=relaxed/simple; bh=BCbQ4pH/5+DZ0kGq+sR5Vig8UGLG8D1dberWTy1yQAg=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=VjurlunOS7w45cOfgP04Kv2kBzhYMqixCbfOxakUX4DfVxZZ3GMxjG40ZgDa9rPbg6PcJ+MvZ9CHtzduHRUvh6yvadQUnIsfI8lLFpcUw7zuzBoXh3yukHFZW2fa7VFbht4POUZqK16Mkv3c/FCpevuDJGq+Aq3OwX7T1d8xUKs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=JefGtnk0; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="JefGtnk0" Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-2163affd184so27765ad.1 for ; Thu, 09 Jan 2025 16:24:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1736468675; x=1737073475; darn=vger.kernel.org; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=BluTxbkEvEv+CQtg9A8nn6RWCkB7gt2VxsHttz6NB8k=; b=JefGtnk0KtTyjInH/3DIGj1S5EYAlcEXkLz2wqWMHRCh4w1i23DNG4/NY102ILZdAP fEkPHIfi7G6oVeLog+z5YQbuJG0URC3G7615KdfhOM72o3rEaBiC+5XRC6XYzn4J4zrG wD2ASlnmYmszSyR4/hcWL2OzhQMVO6TPoAlHV3tjCSuV23SUc6JZI+uBeWn21UVz95tN /NI1BTzx//XjbeZJHf/BI4xtmteGGSuvmUA3pge7eGTT6p7JrD/0fxg2r8Iv6/03JrmS hbltKaUlGd8mYqefyhK0mIjd6cccTpNw7HWg2xxWrQNE+s0WcZr1Yh3RoeMadAe5xybs 5vpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736468675; x=1737073475; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=BluTxbkEvEv+CQtg9A8nn6RWCkB7gt2VxsHttz6NB8k=; b=feHxnvs1yJi9hKdhnd7O2PrLYc/tJFQNbWlkJVQy1vQQEA3S+UBgHX2OBlBi5Oy32R sdHP5mbuPplyzYFkvQ87CP2pk2ch4JN8RdU2BmNUlLJ7SQTKG0vnFk9sgyx+4DJ6VvxF crrIyprb/Asa3B9L3BspZp3dhRO72kDmcmePM9PS6bO/A8u9Z4u8OlJnjuAZ0q0a3+zr gEmgWEjKBFwZM989OGtsgy3uamPUtOyXryRhIzjq/dkdDaE+AwVsqwvYtuDLDDOp8FTm E72loKddDhUL5XZlOApr75P6Q7GocjvV7qW6lJgEwmvlFX3TvtLSLqILUGwOUC8HgPwC 8vHw== X-Forwarded-Encrypted: i=1; AJvYcCX4vW+oPwh49SpaD79b+4R6QBh/yXTBkvvHbtdvU2v3Ved87F069S0WkXjS/AenZ6f5xVLgsXJOw9udMUA=@vger.kernel.org X-Gm-Message-State: AOJu0Ywr+UFI+H8IHCJKFlG/zOz0vOFOI9PS8O5gJi4zpTDg7r3ATtzX YKqwaEUsVBqUEmL8pE0RmXMuO75IKfsJW57S667gCFONRd+WQm4jEIz5xlaMnA== X-Gm-Gg: ASbGnctUXYVDibufAVdp080/SufSNeD+ZhbuRCXFc57J23xFzL7w8tfdLTU/Bx4B9+/ zze/gc9pf04t1NAuMN919a3v72ofw4ZDByiCRkUz9F33q6gNfz9x/isOLee+nEwmD9tdfJDx3dT wT21hv2Soewf9twL9xTTsmTZKw86y5dl5zUN+kwsD+aE8NwGPGM9nFCwz/lxXgEaDySOPvEJBqA EL61j2bg5096Nwww0QGaCmcKN5olrMAcNexuT/CJ5HSnVE3Sp9t8Yy+8LHpjQMftNAB8AzcHuRU rpo7fl/vzrw= X-Google-Smtp-Source: AGHT+IEJEOd/QxHOnkX8cbc6v07rAePwSMbIltninT0B7y6Hc1Uo/jIsP9vX9goGsY7h3TDKR0L1gQ== X-Received: by 2002:a17:903:31d8:b0:216:6dab:8042 with SMTP id d9443c01a7336-21aa07f34a2mr1017235ad.12.1736468674567; Thu, 09 Jan 2025 16:24:34 -0800 (PST) Received: from [2620:0:1008:15:3031:2897:d7d8:ee1b] ([2620:0:1008:15:3031:2897:d7d8:ee1b]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21a9f22c97asm3410545ad.165.2025.01.09.16.24.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Jan 2025 16:24:34 -0800 (PST) Date: Thu, 9 Jan 2025 16:24:33 -0800 (PST) From: David Rientjes To: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot cc: Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , linux-kernel@vger.kernel.org, Madadi Vineeth Reddy , Josh Don Subject: [patch v2] sched/debug: Change need_resched warnings to pr_err In-Reply-To: <99090633-b625-ff07-fcf8-500d71f9ae13@google.com> Message-ID: References: <99090633-b625-ff07-fcf8-500d71f9ae13@google.com> 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=US-ASCII need_resched warnings, if enabled, are treated as WARNINGs. If kernel.panic_on_warn is enabled, then this causes a kernel panic. It's highly unlikely that a panic is desired for these warnings, only a stack trace is normally required to debug and resolve. Thus, switch need_resched warnings to simply be a printk with an associated stack trace so they are no longer in scope for panic_on_warn. Acked-by: Josh Don Reviewed-by: Madadi Vineeth Reddy Signed-off-by: David Rientjes --- v2: added Acked-by and Reviewed-by, dropped second patch in the series kernel/sched/debug.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -1295,8 +1295,10 @@ void resched_latency_warn(int cpu, u64 latency) { static DEFINE_RATELIMIT_STATE(latency_check_ratelimit, 60 * 60 * HZ, 1); - WARN(__ratelimit(&latency_check_ratelimit), - "sched: CPU %d need_resched set for > %llu ns (%d ticks) " - "without schedule\n", - cpu, latency, cpu_rq(cpu)->ticks_without_resched); + if (likely(!__ratelimit(&latency_check_ratelimit))) + return; + + pr_err("sched: CPU %d need_resched set for > %llu ns (%d ticks) without schedule\n", + cpu, latency, cpu_rq(cpu)->ticks_without_resched); + dump_stack(); }