From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 2F7F62E1F0E; Sat, 19 Sep 2026 00:01:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789776062; cv=none; b=TukRogRPpIrdPuRzsd+HDc1mmXmyi+ajxC0vYTw3A3kvN/2gZo/FAJLyEZOe+rTKaZOZ3FQf9yFsnTJwXH+NMCtc/ytP754D0GA3an+biZ68ReYMOEiFaSUNse91+xgcYYbwciq16tdaX0u5EJ7ToCEYCYFPPR3jMrObhTgYsLA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789776062; c=relaxed/simple; bh=wTqnzWv4HcmzQNu1Ciof+W30xKQFFl3O6JrB+4Yt/Jg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=V38y+rw9KQvLVpjUmBTkLeLkVI2GQfauaSaClvC121gtyF+bvDK0gtfn+upQASXkCSz7YjIibwtKaFej/qlpsfGUrIqshxYGOrAZLO4VFjAv5AHYwwWgYAqfLAttq7SEIgFjYoQ454CDOCLlmP4arbAQ5Guj+lOxmsrT+jmUHIk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PXR7IHKM; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PXR7IHKM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CE4ED1F008A2; Sat, 19 Sep 2026 00:00:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789776059; bh=ZlY1fRfzlngUScnswdrpmctWm7EvrHXSppPy3a62Huw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=PXR7IHKMG8PWoy95xLvpoBCO9oPsojUOx4nGTUpf5U96LLoMWwI/1oLWQlm89+DqH DtTjbNhLT6RYSn2Q6WuuRuNv0lvuVLFepOOEVKuJcHsWm3Mz+6hp5X8vuQzCbmsSAl 4yoPCN8LZtg7l5eUw+/vRXJ6GpIwk2sPTqiPcP4gZptQnoKaaG3Ufi78yDKGtq3UiP CdtAdkQNezrdXBJLJDrIloRfKQnkRI2rsJLikuEwTHfhQYqx4zknrb0mAlyFbBIVEa 5P+1eZzmCHOigeVS4w0Lp1Y+P4LpVLrAt5jIXREBwcDCs/0kt4Xg200Th8UK638VQJ eQUjyN1gNyjjQ== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 60459CE0AC0; Fri, 18 Sep 2026 17:00:59 -0700 (PDT) From: "Paul E. McKenney" To: rcu@vger.kernel.org, linux-kernel@vger.kernel.org Cc: kernel-team@meta.com, Mathieu Desnoyers , Boqun Feng , Steven Rostedt , lkmm@lists.linux.dev, Zqiang , Wang Lian , Kunwu Chan , Bradley Morgan , "Paul E. McKenney" Subject: [PATCH 08/28] hazptrtorture: Use mnemonic local variables for context information Date: Fri, 18 Sep 2026 17:00:36 -0700 Message-Id: <20260919000056.3132131-8-paulmck@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This commit introduces can_sleep and short_spin local variables to hazptr_read_delay(). The can_sleep variable records whether unconstrained sleeping is feasible, and the short_spin variable checks for the NMI handlers, IRQ handlers, or disabled interrupts/softirqs suggesting short spin times. While in the area, it disables the reader_sleep_us module parameter when invoked where sleeping is not permitted. Signed-off-by: Paul E. McKenney Cc: Boqun Feng Cc: Mathieu Desnoyers Cc: Cc: --- kernel/rcu/hazptrtorture.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/rcu/hazptrtorture.c b/kernel/rcu/hazptrtorture.c index e9ba25f156ac..c0ebabdcc72e 100644 --- a/kernel/rcu/hazptrtorture.c +++ b/kernel/rcu/hazptrtorture.c @@ -204,23 +204,25 @@ static struct hazptr_torture *hazptr_torture_read_lock(struct hazptr_ctx **hcpp) static void hazptr_read_delay(struct torture_random_state *rrsp) { + const bool can_sleep = !preempt_count() && !irqs_disabled(); const unsigned long shortdelay_us = 200; unsigned long longdelay_ms = 300; + const bool short_spin = irqs_disabled() || irq_count(); // We want a short delay sometimes to make a reader delay the grace // period, and we want a long delay occasionally to trigger // force_quiescent_state. if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) { - if ((preempt_count() & HARDIRQ_MASK) || softirq_count()) + if (short_spin) longdelay_ms = 5; /* Avoid triggering BH limits. */ mdelay(longdelay_ms); } if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) udelay(shortdelay_us); - if (!preempt_count() && !(torture_random(rrsp) % (nrealreaders * 500))) + if (can_sleep && !(torture_random(rrsp) % (nrealreaders * 500))) torture_preempt_schedule(); /* QS only if preemptible. */ - if (reader_sleep_us > 0) + if (can_sleep && reader_sleep_us > 0) torture_hrtimeout_us(reader_sleep_us, 0, NULL); } -- 2.40.1