From patchwork Wed Oct 9 18:07:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 13828956 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 003F01E1A37; Wed, 9 Oct 2024 18:07:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728497242; cv=none; b=ZnEMCcdXPFvQqTxvZwjh/7MFDT3GX2qQiVbGtZAgcTllaNb+nZIMij5SzJ2sc3Q0+RIiwdccCs83+pblkKvNHEocTS478fcgHIJKd63szlSR61jVGOUTLZGAF+hZqBM8EzxSKeCpvi/pR+wFuGVmLpSTGWy8x3iey7pqtPA230U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728497242; c=relaxed/simple; bh=8hfp/Du5Ub9QEkjtr1jYWVVr4ZGe06rAIhqfw3Hf/sc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Nu80CVzE/3SljmBgDKnEya0Tk4EllFEf+IP4KC49849IaTh9yBAxZ3DNgm7yMsvetxLBcUdqivF6DSMlIjOGIfnnMe++W7aaSYRpvvGXuwjQ28z4D9+DoMXF+TDGQw8YlB021HAbbwHNQb8GYnyg97zxEGEF+w7L50PI12vc640= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=R2Bove1C; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="R2Bove1C" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B19A6C4CEDD; Wed, 9 Oct 2024 18:07:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728497241; bh=8hfp/Du5Ub9QEkjtr1jYWVVr4ZGe06rAIhqfw3Hf/sc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R2Bove1CxN9O3t+3f4epgXH9FlAwJt8guCyG6qgqYxPERi41AXQBBh+Ft1HLNTZWD 8MJnaZxUFg8QQLp0Oqn6fIYPOLx5UwBy4+/Om4arXhBvr6AVyovGdRbKqCskD8w6l6 zZmLF2HYjoKcZs7ZBLFQMG+RRqvAHBkka1P3ZAyGzwZ/WGTNZRrDyIfMO1also+gT3 /Yk28W/gPyOqFy+jihd8Fuga+wGGUGMAJ5CWVmook/48oivGDvcua/JbR41q22x3ln ol/MNPxE2Xa3MG/SPPIqNeqtweZDUjsAuTc8EDMeOhfYeUvmtka2N62sWMKXoL5qoz CzWrqIjecIPSw== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 260C3CE1291; Wed, 9 Oct 2024 11:07:21 -0700 (PDT) From: "Paul E. McKenney" To: frederic@kernel.org, rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org, "Paul E. McKenney" , Alexei Starovoitov , Andrii Nakryiko , Peter Zijlstra , Kent Overstreet , bpf@vger.kernel.org Subject: [PATCH rcu 08/12] rcutorture: Expand RCUTORTURE_RDR_MASK_[12] to eight bits Date: Wed, 9 Oct 2024 11:07:15 -0700 Message-Id: <20241009180719.778285-8-paulmck@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This commit prepares for testing of multiple SRCU reader flavors by expanding RCUTORTURE_RDR_MASK_1 and RCUTORTURE_RDR_MASK_2 from a single bit to eight bits, allowing them to accommodate the return values from multiple calls to srcu_read_lock*(). This will in turn permit better testing coverage for these SRCU reader flavors, including testing of the diagnostics for inproper use of mixed reader flavors. Signed-off-by: Paul E. McKenney Cc: Alexei Starovoitov Cc: Andrii Nakryiko Cc: Peter Zijlstra Cc: Kent Overstreet Cc: --- kernel/rcu/rcutorture.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 3ac8c69dd5bc9..ea71a23b45d8b 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -57,9 +57,9 @@ MODULE_AUTHOR("Paul E. McKenney and Josh Triplett extendables field, extendables param, and related definitions. */ #define RCUTORTURE_RDR_SHIFT_1 8 /* Put SRCU index in upper bits. */ -#define RCUTORTURE_RDR_MASK_1 (1 << RCUTORTURE_RDR_SHIFT_1) -#define RCUTORTURE_RDR_SHIFT_2 9 /* Put SRCU index in upper bits. */ -#define RCUTORTURE_RDR_MASK_2 (1 << RCUTORTURE_RDR_SHIFT_2) +#define RCUTORTURE_RDR_MASK_1 (0xff << RCUTORTURE_RDR_SHIFT_1) +#define RCUTORTURE_RDR_SHIFT_2 16 /* Put SRCU index in upper bits. */ +#define RCUTORTURE_RDR_MASK_2 (0xff << RCUTORTURE_RDR_SHIFT_2) #define RCUTORTURE_RDR_BH 0x01 /* Extend readers by disabling bh. */ #define RCUTORTURE_RDR_IRQ 0x02 /* ... disabling interrupts. */ #define RCUTORTURE_RDR_PREEMPT 0x04 /* ... disabling preemption. */ @@ -71,6 +71,9 @@ MODULE_AUTHOR("Paul E. McKenney and Josh Triplett > RCUTORTURE_RDR_SHIFT_2) > 1); + WARN_ON_ONCE(idxold2 & ~RCUTORTURE_RDR_ALLBITS); rtrsp->rt_readstate = newstate; /* First, put new protection in place to avoid critical-section gap. */ @@ -1850,9 +1853,9 @@ static void rcutorture_one_extend(int *readstate, int newstate, if (statesnew & RCUTORTURE_RDR_SCHED) rcu_read_lock_sched(); if (statesnew & RCUTORTURE_RDR_RCU_1) - idxnew1 = (cur_ops->readlock() & 0x1) << RCUTORTURE_RDR_SHIFT_1; + idxnew1 = (cur_ops->readlock() << RCUTORTURE_RDR_SHIFT_1) & RCUTORTURE_RDR_MASK_1; if (statesnew & RCUTORTURE_RDR_RCU_2) - idxnew2 = (cur_ops->readlock() & 0x1) << RCUTORTURE_RDR_SHIFT_2; + idxnew2 = (cur_ops->readlock() << RCUTORTURE_RDR_SHIFT_2) & RCUTORTURE_RDR_MASK_2; /* * Next, remove old protection, in decreasing order of strength @@ -1872,7 +1875,7 @@ static void rcutorture_one_extend(int *readstate, int newstate, if (statesold & RCUTORTURE_RDR_RBH) rcu_read_unlock_bh(); if (statesold & RCUTORTURE_RDR_RCU_2) { - cur_ops->readunlock((idxold2 >> RCUTORTURE_RDR_SHIFT_2) & 0x1); + cur_ops->readunlock((idxold2 & RCUTORTURE_RDR_MASK_2) >> RCUTORTURE_RDR_SHIFT_2); WARN_ON_ONCE(idxnew2 != -1); idxold2 = 0; } @@ -1882,7 +1885,7 @@ static void rcutorture_one_extend(int *readstate, int newstate, lockit = !cur_ops->no_pi_lock && !statesnew && !(torture_random(trsp) & 0xffff); if (lockit) raw_spin_lock_irqsave(¤t->pi_lock, flags); - cur_ops->readunlock((idxold1 >> RCUTORTURE_RDR_SHIFT_1) & 0x1); + cur_ops->readunlock((idxold1 & RCUTORTURE_RDR_MASK_1) >> RCUTORTURE_RDR_SHIFT_1); WARN_ON_ONCE(idxnew1 != -1); idxold1 = 0; if (lockit) @@ -1897,16 +1900,13 @@ static void rcutorture_one_extend(int *readstate, int newstate, if (idxnew1 == -1) idxnew1 = idxold1 & RCUTORTURE_RDR_MASK_1; WARN_ON_ONCE(idxnew1 < 0); - if (WARN_ON_ONCE((idxnew1 >> RCUTORTURE_RDR_SHIFT_1) > 1)) - pr_info("Unexpected idxnew1 value of %#x\n", idxnew1); if (idxnew2 == -1) idxnew2 = idxold2 & RCUTORTURE_RDR_MASK_2; WARN_ON_ONCE(idxnew2 < 0); - WARN_ON_ONCE((idxnew2 >> RCUTORTURE_RDR_SHIFT_2) > 1); *readstate = idxnew1 | idxnew2 | newstate; WARN_ON_ONCE(*readstate < 0); - if (WARN_ON_ONCE((*readstate >> RCUTORTURE_RDR_SHIFT_2) > 1)) - pr_info("Unexpected idxnew2 value of %#x\n", idxnew2); + if (WARN_ON_ONCE(*readstate & ~RCUTORTURE_RDR_ALLBITS)) + pr_info("Unexpected readstate value of %#x\n", *readstate); } /* Return the biggest extendables mask given current RCU and boot parameters. */ @@ -1931,7 +1931,7 @@ rcutorture_extend_mask(int oldmask, struct torture_random_state *trsp) unsigned long preempts_irq = preempts | RCUTORTURE_RDR_IRQ; unsigned long bhs = RCUTORTURE_RDR_BH | RCUTORTURE_RDR_RBH; - WARN_ON_ONCE(mask >> RCUTORTURE_RDR_SHIFT_1); + WARN_ON_ONCE(mask >> RCUTORTURE_RDR_SHIFT_1); // Can't have reader idx bits. /* Mostly only one bit (need preemption!), sometimes lots of bits. */ if (!(randmask1 & 0x7)) mask = mask & randmask2;