From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: [PATCH memory-model 01/14] tools/memory-model: Add litmus test for full multicopy atomicity Date: Mon, 16 Jul 2018 11:05:52 -0700 Message-ID: <20180716180605.16115-1-paulmck@linux.vnet.ibm.com> References: <20180716180540.GA14222@linux.vnet.ibm.com> Return-path: In-Reply-To: <20180716180540.GA14222@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, mingo@kernel.org Cc: stern@rowland.harvard.edu, parri.andrea@gmail.com, will.deacon@arm.com, peterz@infradead.org, boqun.feng@gmail.com, npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk, luc.maranget@inria.fr, akiyks@gmail.com, "Paul E. McKenney" List-Id: linux-arch.vger.kernel.org This commit adds a litmus test suggested by Alan Stern that is forbidden on fully multicopy atomic systems, but allowed on other-multicopy and on non-multicopy atomic systems. For reference, s390 is fully multicopy atomic, x86 and ARMv8 are other-multicopy atomic, and ARMv7 and powerpc are non-multicopy atomic. Suggested-by: Alan Stern Signed-off-by: Paul E. McKenney Acked-by: Alan Stern Acked-by: Andrea Parri --- tools/memory-model/litmus-tests/README | 9 ++++++ .../SB+rfionceonce-poonceonces.litmus | 32 +++++++++++++++++++ 2 files changed, 41 insertions(+) create mode 100644 tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus diff --git a/tools/memory-model/litmus-tests/README b/tools/memory-model/litmus-tests/README index 17eb9a8c222d..00140aaf58b7 100644 --- a/tools/memory-model/litmus-tests/README +++ b/tools/memory-model/litmus-tests/README @@ -111,6 +111,15 @@ SB+mbonceonces.litmus SB+poonceonces.litmus As above, but without the smp_mb() invocations. +SB+rfionceonce-poonceonces.litmus + This litmus test demonstrates that LKMM is not fully multicopy + atomic. (Neither is it other multicopy atomic.) This litmus test + also demonstrates the "locations" debugging aid, which designates + additional registers and locations to be printed out in the dump + of final states in the herd7 output. Without the "locations" + statement, only those registers and locations mentioned in the + "exists" clause will be printed. + S+poonceonces.litmus As below, but without the smp_wmb() and acquire load. diff --git a/tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus b/tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus new file mode 100644 index 000000000000..04a16603660b --- /dev/null +++ b/tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus @@ -0,0 +1,32 @@ +C SB+rfionceonce-poonceonces + +(* + * Result: Sometimes + * + * This litmus test demonstrates that LKMM is not fully multicopy atomic. + *) + +{} + +P0(int *x, int *y) +{ + int r1; + int r2; + + WRITE_ONCE(*x, 1); + r1 = READ_ONCE(*x); + r2 = READ_ONCE(*y); +} + +P1(int *x, int *y) +{ + int r3; + int r4; + + WRITE_ONCE(*y, 1); + r3 = READ_ONCE(*y); + r4 = READ_ONCE(*x); +} + +locations [0:r1; 1:r3; x; y] (* Debug aid: Print things not in "exists". *) +exists (0:r2=0 /\ 1:r4=0) -- 2.17.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:46830 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728558AbeGPScV (ORCPT ); Mon, 16 Jul 2018 14:32:21 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w6GHxFfp044881 for ; Mon, 16 Jul 2018 14:03:50 -0400 Received: from e14.ny.us.ibm.com (e14.ny.us.ibm.com [129.33.205.204]) by mx0a-001b2d01.pphosted.com with ESMTP id 2k8w190t76-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 16 Jul 2018 14:03:49 -0400 Received: from localhost by e14.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 16 Jul 2018 14:03:48 -0400 From: "Paul E. McKenney" Subject: [PATCH memory-model 01/14] tools/memory-model: Add litmus test for full multicopy atomicity Date: Mon, 16 Jul 2018 11:05:52 -0700 In-Reply-To: <20180716180540.GA14222@linux.vnet.ibm.com> References: <20180716180540.GA14222@linux.vnet.ibm.com> Message-ID: <20180716180605.16115-1-paulmck@linux.vnet.ibm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, mingo@kernel.org Cc: stern@rowland.harvard.edu, parri.andrea@gmail.com, will.deacon@arm.com, peterz@infradead.org, boqun.feng@gmail.com, npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk, luc.maranget@inria.fr, akiyks@gmail.com, "Paul E. McKenney" Message-ID: <20180716180552.M_4rWl7t8f2OfKjPVZSQSRFNawJSbe9T1c4XPLoC0xs@z> This commit adds a litmus test suggested by Alan Stern that is forbidden on fully multicopy atomic systems, but allowed on other-multicopy and on non-multicopy atomic systems. For reference, s390 is fully multicopy atomic, x86 and ARMv8 are other-multicopy atomic, and ARMv7 and powerpc are non-multicopy atomic. Suggested-by: Alan Stern Signed-off-by: Paul E. McKenney Acked-by: Alan Stern Acked-by: Andrea Parri --- tools/memory-model/litmus-tests/README | 9 ++++++ .../SB+rfionceonce-poonceonces.litmus | 32 +++++++++++++++++++ 2 files changed, 41 insertions(+) create mode 100644 tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus diff --git a/tools/memory-model/litmus-tests/README b/tools/memory-model/litmus-tests/README index 17eb9a8c222d..00140aaf58b7 100644 --- a/tools/memory-model/litmus-tests/README +++ b/tools/memory-model/litmus-tests/README @@ -111,6 +111,15 @@ SB+mbonceonces.litmus SB+poonceonces.litmus As above, but without the smp_mb() invocations. +SB+rfionceonce-poonceonces.litmus + This litmus test demonstrates that LKMM is not fully multicopy + atomic. (Neither is it other multicopy atomic.) This litmus test + also demonstrates the "locations" debugging aid, which designates + additional registers and locations to be printed out in the dump + of final states in the herd7 output. Without the "locations" + statement, only those registers and locations mentioned in the + "exists" clause will be printed. + S+poonceonces.litmus As below, but without the smp_wmb() and acquire load. diff --git a/tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus b/tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus new file mode 100644 index 000000000000..04a16603660b --- /dev/null +++ b/tools/memory-model/litmus-tests/SB+rfionceonce-poonceonces.litmus @@ -0,0 +1,32 @@ +C SB+rfionceonce-poonceonces + +(* + * Result: Sometimes + * + * This litmus test demonstrates that LKMM is not fully multicopy atomic. + *) + +{} + +P0(int *x, int *y) +{ + int r1; + int r2; + + WRITE_ONCE(*x, 1); + r1 = READ_ONCE(*x); + r2 = READ_ONCE(*y); +} + +P1(int *x, int *y) +{ + int r3; + int r4; + + WRITE_ONCE(*y, 1); + r3 = READ_ONCE(*y); + r4 = READ_ONCE(*x); +} + +locations [0:r1; 1:r3; x; y] (* Debug aid: Print things not in "exists". *) +exists (0:r2=0 /\ 1:r4=0) -- 2.17.1