From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7216BC43217 for ; Tue, 22 Nov 2022 20:40:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234930AbiKVUj7 (ORCPT ); Tue, 22 Nov 2022 15:39:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234891AbiKVUjw (ORCPT ); Tue, 22 Nov 2022 15:39:52 -0500 Received: from smtpout.efficios.com (unknown [IPv6:2607:5300:203:b2ee::31e5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F1B76A680; Tue, 22 Nov 2022 12:39:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1669149586; bh=CQf8TrHt8laQTUgKpTFJW2JD3X3wApVWzx7Jjn4JOhg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mwe0fVMWwELA4lSoeJGvWxpBGxAc5D63aSOipG31fzp0hJNURlighP5jai3B0QnJ5 fr92DoJaeHo7Qp9Ek38Gu6fO6sztlT1Tm1M1hRd2T4H6bs7hEwUrY+VpPMiq06iVgf vTn6OHvFdJ5VeVIntsBYqOHshEypx9gNyb2MPE+ZLFVONxEz8usODizbNhmEiuv8jr iRt3H34pcuuYyJO6EKk92YTcUXboV6EC60M2O2TH09wMZhGCrY/vZpSI+UsKn3Aqnu IjaArgAfXCRT69PeSzrFvZleC88HMT4i1tj26DI194kBTc8qKlNCVtsfF3vRV7yShC nJibA4tEuSmrg== Received: from localhost.localdomain (192-222-180-24.qc.cable.ebox.net [192.222.180.24]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4NGx2V47MlzXRC; Tue, 22 Nov 2022 15:39:46 -0500 (EST) From: Mathieu Desnoyers To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Thomas Gleixner , "Paul E . McKenney" , Boqun Feng , "H . Peter Anvin" , Paul Turner , linux-api@vger.kernel.org, Christian Brauner , Florian Weimer , David.Laight@ACULAB.COM, carlos@redhat.com, Peter Oskolkov , Alexander Mikhalitsyn , Chris Kennelly , Mathieu Desnoyers Subject: [PATCH 06/30] selftests/rseq: Implement rseq numa node id field selftest Date: Tue, 22 Nov 2022 15:39:08 -0500 Message-Id: <20221122203932.231377-7-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221122203932.231377-1-mathieu.desnoyers@efficios.com> References: <20221122203932.231377-1-mathieu.desnoyers@efficios.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org Test the NUMA node id extension rseq field. Compare it against the value returned by the getcpu(2) system call while pinned on a specific core. Signed-off-by: Mathieu Desnoyers --- tools/testing/selftests/rseq/basic_test.c | 4 ++++ tools/testing/selftests/rseq/rseq-abi.h | 8 +++++++ tools/testing/selftests/rseq/rseq.c | 18 +++++++++++++++ tools/testing/selftests/rseq/rseq.h | 28 +++++++++++++++++++++++ 4 files changed, 58 insertions(+) diff --git a/tools/testing/selftests/rseq/basic_test.c b/tools/testing/selftests/rseq/basic_test.c index d8efbfb89193..295eea16466f 100644 --- a/tools/testing/selftests/rseq/basic_test.c +++ b/tools/testing/selftests/rseq/basic_test.c @@ -22,6 +22,8 @@ void test_cpu_pointer(void) CPU_ZERO(&test_affinity); for (i = 0; i < CPU_SETSIZE; i++) { if (CPU_ISSET(i, &affinity)) { + int node; + CPU_SET(i, &test_affinity); sched_setaffinity(0, sizeof(test_affinity), &test_affinity); @@ -29,6 +31,8 @@ void test_cpu_pointer(void) assert(rseq_current_cpu() == i); assert(rseq_current_cpu_raw() == i); assert(rseq_cpu_start() == i); + node = rseq_fallback_current_node(); + assert(rseq_current_node_id() == node); CPU_CLR(i, &test_affinity); } } diff --git a/tools/testing/selftests/rseq/rseq-abi.h b/tools/testing/selftests/rseq/rseq-abi.h index 00ac846d85b0..a1faa9162d52 100644 --- a/tools/testing/selftests/rseq/rseq-abi.h +++ b/tools/testing/selftests/rseq/rseq-abi.h @@ -147,6 +147,14 @@ struct rseq_abi { */ __u32 flags; + /* + * Restartable sequences node_id field. Updated by the kernel. Read by + * user-space with single-copy atomicity semantics. This field should + * only be read by the thread which registered this data structure. + * Aligned on 32-bit. Contains the current NUMA node ID. + */ + __u32 node_id; + /* * Flexible array member at end of structure, after last feature field. */ diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c index 1e8e3265bdbf..4e4aa006004c 100644 --- a/tools/testing/selftests/rseq/rseq.c +++ b/tools/testing/selftests/rseq/rseq.c @@ -79,6 +79,11 @@ static int sys_rseq(struct rseq_abi *rseq_abi, uint32_t rseq_len, return syscall(__NR_rseq, rseq_abi, rseq_len, flags, sig); } +static int sys_getcpu(unsigned *cpu, unsigned *node) +{ + return syscall(__NR_getcpu, cpu, node, NULL); +} + int rseq_available(void) { int rc; @@ -201,3 +206,16 @@ int32_t rseq_fallback_current_cpu(void) } return cpu; } + +int32_t rseq_fallback_current_node(void) +{ + uint32_t cpu_id, node_id; + int ret; + + ret = sys_getcpu(&cpu_id, &node_id); + if (ret) { + perror("sys_getcpu()"); + return ret; + } + return (int32_t) node_id; +} diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h index 95adc1e1b0db..fd17d0e54a1b 100644 --- a/tools/testing/selftests/rseq/rseq.h +++ b/tools/testing/selftests/rseq/rseq.h @@ -20,6 +20,15 @@ #include "rseq-abi.h" #include "compiler.h" +#ifndef rseq_sizeof_field +#define rseq_sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER)) +#endif + +#ifndef rseq_offsetofend +#define rseq_offsetofend(TYPE, MEMBER) \ + (offsetof(TYPE, MEMBER) + rseq_sizeof_field(TYPE, MEMBER)) +#endif + /* * Empty code injection macros, override when testing. * It is important to consider that the ASM injection macros need to be @@ -128,6 +137,11 @@ int rseq_unregister_current_thread(void); */ int32_t rseq_fallback_current_cpu(void); +/* + * Restartable sequence fallback for reading the current node number. + */ +int32_t rseq_fallback_current_node(void); + /* * Values returned can be either the current CPU number, -1 (rseq is * uninitialized), or -2 (rseq initialization has failed). @@ -163,6 +177,20 @@ static inline uint32_t rseq_current_cpu(void) return cpu; } +static inline bool rseq_node_id_available(void) +{ + return (int) rseq_feature_size >= rseq_offsetofend(struct rseq_abi, node_id); +} + +/* + * Current NUMA node number. + */ +static inline uint32_t rseq_current_node_id(void) +{ + assert(rseq_node_id_available()); + return RSEQ_ACCESS_ONCE(rseq_get_abi()->node_id); +} + static inline void rseq_clear_rseq_cs(void) { RSEQ_WRITE_ONCE(rseq_get_abi()->rseq_cs.arch.ptr, 0); -- 2.25.1