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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 96502C3DA49 for ; Thu, 11 Jul 2024 17:01:30 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sRx9o-0002ba-KL; Thu, 11 Jul 2024 13:00:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sRx9W-0002S6-Os; Thu, 11 Jul 2024 13:00:20 -0400 Received: from mail.ozlabs.org ([2404:9400:2221:ea00::3]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sRx9Q-0003J0-KD; Thu, 11 Jul 2024 13:00:17 -0400 Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4WKgvT1lqwz4x12; Fri, 12 Jul 2024 03:00:05 +1000 (AEST) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4WKgvR1kVGz4wbr; Fri, 12 Jul 2024 03:00:02 +1000 (AEST) Message-ID: Date: Thu, 11 Jul 2024 19:00:00 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 18/18] ppc/pnv: Add an LPAR per core machine option To: Nicholas Piggin , qemu-ppc@nongnu.org Cc: =?UTF-8?B?RnLDqWTDqXJpYyBCYXJyYXQ=?= , Harsh Prateek Bora , qemu-devel@nongnu.org References: <20240711141851.406677-1-npiggin@gmail.com> <20240711141851.406677-19-npiggin@gmail.com> Content-Language: en-US, fr From: =?UTF-8?Q?C=C3=A9dric_Le_Goater?= In-Reply-To: <20240711141851.406677-19-npiggin@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=2404:9400:2221:ea00::3; envelope-from=SRS0=SBUb=OL=kaod.org=clg@ozlabs.org; helo=mail.ozlabs.org X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.001, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 7/11/24 16:18, Nicholas Piggin wrote: > Recent POWER CPUs can operate in "LPAR per core" or "LPAR per thread" > modes. In per-core mode, some SPRs and IPI doorbells are shared between > threads in a core. In per-thread mode, supervisor and user state is > not shared between threads. > > OpenPOWER systems after POWER8 use LPAR per thread mode, and it is > required for KVM. Enterprise systems use LPAR per core mode, as they > partition the machine by core. > > Implement a lpar-per-core machine option for powernv machines. This > is fixed true for POWER8 machines, and defaults off for P9 and P10. > > With this change, powernv8 SMT now works sufficiently to run Linux, > including KVM. > > Signed-off-by: Nicholas Piggin > --- > include/hw/ppc/pnv.h | 1 + > include/hw/ppc/pnv_core.h | 1 + > hw/ppc/pnv.c | 29 +++++++++++++++++++++++++++++ > hw/ppc/pnv_core.c | 8 ++++++++ > target/ppc/cpu_init.c | 3 ++- > 5 files changed, 41 insertions(+), 1 deletion(-) > > diff --git a/include/hw/ppc/pnv.h b/include/hw/ppc/pnv.h > index b7858d310d..73f0d72f55 100644 > --- a/include/hw/ppc/pnv.h > +++ b/include/hw/ppc/pnv.h > @@ -104,6 +104,7 @@ struct PnvMachineState { > hwaddr fw_load_addr; > > bool big_core; > + bool lpar_per_core; > }; > > PnvChip *pnv_get_chip(PnvMachineState *pnv, uint32_t chip_id); > diff --git a/include/hw/ppc/pnv_core.h b/include/hw/ppc/pnv_core.h > index 1de79a818e..d8afb4f95f 100644 > --- a/include/hw/ppc/pnv_core.h > +++ b/include/hw/ppc/pnv_core.h > @@ -57,6 +57,7 @@ struct PnvCore { > /*< public >*/ > PowerPCCPU **threads; > bool big_core; > + bool lpar_per_core; > uint32_t pir; > uint32_t hwid; > uint64_t hrmor; > diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c > index 71b2b3806c..f9a05fa0ff 100644 > --- a/hw/ppc/pnv.c > +++ b/hw/ppc/pnv.c > @@ -1026,6 +1026,11 @@ static void pnv_init(MachineState *machine) > exit(1); > } > > + if (!object_property_find(OBJECT(pnv), "lpar-per-core")) { > + /* POWER8 is always in lpar-per-core mode */ > + pnv->lpar_per_core = true; > + } yep. A better alternative would be to introduce a PnvChipClass::lpar_per_core attribute (set to true for POWER8) and OR PnvChipClass::lpar_per_core with pnv->lpar_per_core to set the "lpar-per-core" property of PnvCore in pnv_chip_core_realize(). Thanks, C. > pnv->num_chips = > machine->smp.max_cpus / (machine->smp.cores * machine->smp.threads); > > @@ -2589,6 +2594,18 @@ static void pnv_machine_set_big_core(Object *obj, bool value, Error **errp) > pnv->big_core = value; > } > > +static bool pnv_machine_get_1lpar(Object *obj, Error **errp) > +{ > + PnvMachineState *pnv = PNV_MACHINE(obj); > + return pnv->lpar_per_core; > +} > + > +static void pnv_machine_set_1lpar(Object *obj, bool value, Error **errp) > +{ > + PnvMachineState *pnv = PNV_MACHINE(obj); > + pnv->lpar_per_core = value; > +} > + > static bool pnv_machine_get_hb(Object *obj, Error **errp) > { > PnvMachineState *pnv = PNV_MACHINE(obj); > @@ -2662,6 +2679,12 @@ static void pnv_machine_power9_class_init(ObjectClass *oc, void *data) > pnv_machine_set_big_core); > object_class_property_set_description(oc, "big-core", > "Use big-core (aka fused-core) mode"); > + > + object_class_property_add_bool(oc, "lpar-per-core", > + pnv_machine_get_1lpar, > + pnv_machine_set_1lpar); > + object_class_property_set_description(oc, "lpar-per-core", > + "Use 1 LPAR per core mode"); > } > > static void pnv_machine_p10_common_class_init(ObjectClass *oc, void *data) > @@ -2709,6 +2732,12 @@ static void pnv_machine_power10_class_init(ObjectClass *oc, void *data) > pnv_machine_set_big_core); > object_class_property_set_description(oc, "big-core", > "Use big-core (aka fused-core) mode"); > + > + object_class_property_add_bool(oc, "lpar-per-core", > + pnv_machine_get_1lpar, > + pnv_machine_set_1lpar); > + object_class_property_set_description(oc, "lpar-per-core", > + "Use 1 LPAR per core mode"); > } > > static void pnv_machine_p10_rainier_class_init(ObjectClass *oc, void *data) > diff --git a/hw/ppc/pnv_core.c b/hw/ppc/pnv_core.c > index a685a5dc1b..5a6fcb6edc 100644 > --- a/hw/ppc/pnv_core.c > +++ b/hw/ppc/pnv_core.c > @@ -208,6 +208,9 @@ static uint64_t pnv_core_power10_xscom_read(void *opaque, hwaddr addr, > val |= PPC_BIT(56 + i); > } > } > + if (pc->lpar_per_core) { > + val |= PPC_BIT(62); > + } > break; > case PNV10_XSCOM_EC_CORE_THREAD_INFO: > break; > @@ -320,6 +323,10 @@ static void pnv_core_cpu_realize(PnvCore *pc, PowerPCCPU *cpu, Error **errp, > env->core_index = core_hwid; > } > > + if (pc->lpar_per_core) { > + cpu_ppc_set_1lpar(cpu); > + } > + > /* Set time-base frequency to 512 MHz */ > cpu_ppc_tb_init(env, PNV_TIMEBASE_FREQ); > } > @@ -352,6 +359,7 @@ static void pnv_core_realize(DeviceState *dev, Error **errp) > > pc->big_core = pnv->big_core; > pc->tod_state.big_core_quirk = pmc->quirk_tb_big_core; > + pc->lpar_per_core = pc->chip->pnv_machine->lpar_per_core; > > pc->threads = g_new(PowerPCCPU *, cc->nr_threads); > for (i = 0; i < cc->nr_threads; i++) { > diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c > index 9349001b76..0fc83d5cc2 100644 > --- a/target/ppc/cpu_init.c > +++ b/target/ppc/cpu_init.c > @@ -6785,7 +6785,8 @@ void cpu_ppc_set_1lpar(PowerPCCPU *cpu) > > /* > * pseries SMT means "LPAR per core" mode, e.g., msgsndp is usable > - * between threads. > + * between threads. powernv be in either mode, and it mostly affects > + * supervisor visible registers and instructions. > */ > if (env->flags & POWERPC_FLAG_SMT) { > env->flags |= POWERPC_FLAG_SMT_1LPAR;