From mboxrd@z Thu Jan 1 00:00:00 1970 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 5A08DAD23 for ; Thu, 27 Oct 2022 17:09:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D4993C433D6; Thu, 27 Oct 2022 17:09:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666890595; bh=NQBhZNYcwdFgQ2tQm8AnRjgVXd2tRjcdcteVxcYx9Xc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JM5o/kSGVDde1AXYb2fyEZZvfyzRKWcEJx9gquTGQa/jdQVO9g7IbZr/5EYRtEtOC 19cA0+pFrLGsCRDueRkEcI4mGSQ3PtqDy6l6kfn3aqzkwhXtPVbKs46pk9QWHNmMai zVNNNWG0prZwttp7CPYDqv8bvSVIzS5DYFigiAHw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Brice Goglin , Sudeep Holla , Atish Patra , Conor Dooley Subject: [PATCH 5.4 49/53] riscv: topology: fix default topology reporting Date: Thu, 27 Oct 2022 18:56:37 +0200 Message-Id: <20221027165051.737819607@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221027165049.817124510@linuxfoundation.org> References: <20221027165049.817124510@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Conor Dooley commit fbd92809997a391f28075f1c8b5ee314c225557c upstream. RISC-V has no sane defaults to fall back on where there is no cpu-map in the devicetree. Without sane defaults, the package, core and thread IDs are all set to -1. This causes user-visible inaccuracies for tools like hwloc/lstopo which rely on the sysfs cpu topology files to detect a system's topology. On a PolarFire SoC, which should have 4 harts with a thread each, lstopo currently reports: Machine (793MB total) Package L#0 NUMANode L#0 (P#0 793MB) Core L#0 L1d L#0 (32KB) + L1i L#0 (32KB) + PU L#0 (P#0) L1d L#1 (32KB) + L1i L#1 (32KB) + PU L#1 (P#1) L1d L#2 (32KB) + L1i L#2 (32KB) + PU L#2 (P#2) L1d L#3 (32KB) + L1i L#3 (32KB) + PU L#3 (P#3) Adding calls to store_cpu_topology() in {boot,smp} hart bringup code results in the correct topolgy being reported: Machine (793MB total) Package L#0 NUMANode L#0 (P#0 793MB) L1d L#0 (32KB) + L1i L#0 (32KB) + Core L#0 + PU L#0 (P#0) L1d L#1 (32KB) + L1i L#1 (32KB) + Core L#1 + PU L#1 (P#1) L1d L#2 (32KB) + L1i L#2 (32KB) + Core L#2 + PU L#2 (P#2) L1d L#3 (32KB) + L1i L#3 (32KB) + Core L#3 + PU L#3 (P#3) CC: stable@vger.kernel.org # 456797da792f: arm64: topology: move store_cpu_topology() to shared code Fixes: 03f11f03dbfe ("RISC-V: Parse cpu topology during boot.") Reported-by: Brice Goglin Link: https://github.com/open-mpi/hwloc/issues/536 Reviewed-by: Sudeep Holla Reviewed-by: Atish Patra Signed-off-by: Conor Dooley Signed-off-by: Greg Kroah-Hartman --- arch/riscv/Kconfig | 2 +- arch/riscv/kernel/smpboot.c | 4 +++- 2 files changed, 4 insertions(+), 2 deletions(-) --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -51,7 +51,7 @@ config RISCV select PCI_MSI if PCI select RISCV_TIMER select GENERIC_IRQ_MULTI_HANDLER - select GENERIC_ARCH_TOPOLOGY if SMP + select GENERIC_ARCH_TOPOLOGY select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_MMIOWB select HAVE_EBPF_JIT if 64BIT --- a/arch/riscv/kernel/smpboot.c +++ b/arch/riscv/kernel/smpboot.c @@ -46,6 +46,8 @@ void __init smp_prepare_cpus(unsigned in { int cpuid; + store_cpu_topology(smp_processor_id()); + /* This covers non-smp usecase mandated by "nosmp" option */ if (max_cpus == 0) return; @@ -142,8 +144,8 @@ asmlinkage __visible void __init smp_cal current->active_mm = mm; trap_init(); + store_cpu_topology(smp_processor_id()); notify_cpu_starting(smp_processor_id()); - update_siblings_masks(smp_processor_id()); set_cpu_online(smp_processor_id(), 1); /* * Remote TLB flushes are ignored while the CPU is offline, so emit