From nobody Sun Feb 8 12:32:22 2026 Received: from mail-ej1-f41.google.com (mail-ej1-f41.google.com [209.85.218.41]) (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 36AE23469FC for ; Tue, 23 Dec 2025 20:38:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.41 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766522321; cv=none; b=tB8BnN0wyWpCF8Nmad+SKKLzvzcUeuYVF8jKVypIUASgYoinejlTf+lg9jLpVfhGkRp9dARGHUDhQXC7CwZh8D2y5g50rbbUfUwyMBpATrmFQ22uw3dwQ70sFZHmgwFFrCY2fBum9URoZ3y/5HvbkQe4UhHfy3nq+QuNqldbfCA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766522321; c=relaxed/simple; bh=U2mLUnaNk6KBh2lBSZirplSg/rUfm3SgaSBqdstHXPM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=hf7hZz0Wo7Q700cb6QHLbH6M1nPL6Syn7hYcIrQQo6eadMiusU++xRMB14zFTxeyX9zwfZUXLXz25VoSgqIIFT/HnZKHJLnI1PbyJsLwRJEUqfkYV/7MZOCSaDASzKCSGTxGHfq3QKT40wwqdekC6BGoNrb+wFk/eF4TNTDuokc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=iMz9USBT; arc=none smtp.client-ip=209.85.218.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iMz9USBT" Received: by mail-ej1-f41.google.com with SMTP id a640c23a62f3a-b727f452fffso1029928366b.1 for ; Tue, 23 Dec 2025 12:38:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1766522318; x=1767127118; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=ZbfwEtP0KeF+TxfTOBg3TqAaYtHArsyPKtS/18Vb3VE=; b=iMz9USBTonTO6oBZ3XZ9JhDnzWNt7EQJXhiPUNmiY8r6MibRYw1S1G2KhiGtAjyqJW pQcKE8oS5OwaYXrh07/mDybaKti09zvbBufw16sWDSc887SZpVSSAlRF8zPTRIneDTKY muBr5u+C19xYi8jeTLNFzymhfKwmH71iyIWX6YA+aKAe8Ouh9szL9m5bqd9Xor0rDfvx I4RqiensYOEil6xS+LT04V4Ozpoa0qqR+YsmVw9S7UBTusGyx3coqrV5xM7UWdduEJF1 cQv8AiRcMUF5Bqebn4NSgj/V9iwBgVW8TO0agfN+6YiQ4dwjxd+fVs0Hs+HJ1B791zat ReRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1766522318; x=1767127118; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=ZbfwEtP0KeF+TxfTOBg3TqAaYtHArsyPKtS/18Vb3VE=; b=bwRMTTv1pQzcTeymjy7a6obdSxppuKp23kmF+eR1ShTGt5MjQKrMNeWqUxPvnN7JP7 QFjn2/7i0PXGcCXoGuauk+J2CCxiQs/Uln4t2wvEWKnrR/cGmDwaqBjG9dsSrSOZmMmA m5SuuBj45R5xbkVYf50rYn+W/4u3gBY/8zJm5NFoQp8bNpgp3jfASRGaOGmX560gclp1 WyjPuM7XgDM3WUKhADuPqCFzHDY6Wrqzm6zHJNypvdvtpZvyWn1zE/nn2xEH1wNUG1SW 7085WtWOehXMMU2RbiNGz3iqAjBImOJzJkXuKqwWW4HPGPsXSNTYaNOQR3EI0F1OXb/X uRIw== X-Forwarded-Encrypted: i=1; AJvYcCUaxKKfX6eVeGl7MlqYYeWWHOKEQO97P4uyuHV+oJjdI6DUrathwHTPgY32aBQe6EOAGG2ABH+95B6b+Gc=@vger.kernel.org X-Gm-Message-State: AOJu0YwE21Mnvn4M1sGzSsZ6RpMFwQs2okUE6LlgcrFqwnIU6u/tFRw4 rJKJMhagUpjDs9xdjrFrzVu+vKsFzqzRCUtrgwJeKx9x6971gJWC2SxMI4JOtA== X-Gm-Gg: AY/fxX6stMrnag+GDzVs22n/9aS3Hpf7BI/C8nirB5zLZsR4YAhnP3rN0NDKu5fEmLI N7YS685JY7y66uuFJd2XQlH4dYbQxfRb/onC+zRDNF6fsHdPpY6HspENWwOWGJx4soWHNYnKdQQ lI0VGgBM/1NiTwXVa0Asq2+tD6zy52VVprgFPvl83n+DKqw1lOAgu46CiBBdlaDrO9YvCln0bcv thB5BRK7jQmk8a+i1BSzn+RZ9GFVh2tUUue3NDz5kWAVFSCdUEcAl6c2/559uetZxLBUTCqZ1yi 2HOX4wssb/jj8LLOz8ncKMaZB0n8c93CFtruoqExtASV4QwDU/lcPITp2NiVNqh8qkUIROHB+Ng kRg8yitylQHrTvGBWKGMl7iaQVRTD/tuqNA/92qRNGHqKboBsjkzTPk5HWas7zy6RuoCy9OwC5p ti/zyDKivK6wY71BxCSxVOT7om41Oc+Pwb X-Google-Smtp-Source: AGHT+IGhNViUe/EAk1WWZg3GKkFrE0d+eu8HdX/iL5Nh7jAuxWEiIns7rz+g51ZLMq7fQ0EZ7Min+Q== X-Received: by 2002:a17:907:d12:b0:b76:d8cc:dfd9 with SMTP id a640c23a62f3a-b802058edb8mr2069673066b.18.1766522318276; Tue, 23 Dec 2025 12:38:38 -0800 (PST) Received: from localhost.localdomain ([105.42.152.221]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b8037ab69fasm1510720866b.16.2025.12.23.12.38.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Dec 2025 12:38:37 -0800 (PST) From: Khaled Saleh To: rostedt@goodmis.org Cc: mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-kernel@vger.kernel.org, Khaled Saleh Subject: [PATCH] trace: make ftrace likely counters atomic Date: Tue, 23 Dec 2025 22:37:14 +0200 Message-ID: <20251223203715.10954-1-khaled.saleh.req@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The correct and incorrect counters in ftrace_likely_update() are updated without synchronization and may race on SMP systems. Convert them to atomic counters to address the existing FIXME without changing behavior. Signed-off-by: Khaled Saleh --- kernel/trace/trace_branch.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index 6809b370e991..31a144fa975f 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -215,10 +215,11 @@ void ftrace_likely_update(struct ftrace_likely_data *= f, int val, trace_likely_condition(f, val, expect); =20 /* FIXME: Make this atomic! */ - if (val =3D=3D expect) - f->data.correct++; - else - f->data.incorrect++; + if (val =3D=3D expect) { + atomic_long_inc(&f->data.correct); + } else { + atomic_long_inc(&f->data.incorrect); + } =20 user_access_restore(flags); } --=20 2.43.0