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[2001:4830:134:3::11]) by mx.google.com with ESMTPS id v17si2499918ywh.539.2017.11.10.12.36.06 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 10 Nov 2017 12:36:06 -0800 (PST) Received-SPF: pass (google.com: domain of qemu-devel-bounces+alex.bennee=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) client-ip=2001:4830:134:3::11; Authentication-Results: mx.google.com; spf=pass (google.com: domain of qemu-devel-bounces+alex.bennee=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) smtp.mailfrom=qemu-devel-bounces+alex.bennee=linaro.org@nongnu.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from localhost ([::1]:43402 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eDG21-0004jp-NO for alex.bennee@linaro.org; Fri, 10 Nov 2017 15:36:05 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55244) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eDFyW-00025P-Ry for qemu-devel@nongnu.org; Fri, 10 Nov 2017 15:32:30 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eDFyV-0004eL-F1 for qemu-devel@nongnu.org; Fri, 10 Nov 2017 15:32:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53990) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eDFyQ-0004bg-3A; Fri, 10 Nov 2017 15:32:22 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2114980C1E; Fri, 10 Nov 2017 20:32:21 +0000 (UTC) Received: from localhost (ovpn-116-2.gru2.redhat.com [10.97.116.2]) by smtp.corp.redhat.com (Postfix) with ESMTP id 89140171E2; Fri, 10 Nov 2017 20:32:15 +0000 (UTC) Date: Fri, 10 Nov 2017 18:32:13 -0200 From: Eduardo Habkost To: "Emilio G. Cota" Message-ID: <20171110203213.GV3111@localhost.localdomain> References: <1510343626-25861-1-git-send-email-cota@braap.org> <1510343626-25861-6-git-send-email-cota@braap.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1510343626-25861-6-git-send-email-cota@braap.org> X-Fnord: you can see the fnord User-Agent: Mutt/1.9.1 (2017-09-22) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 10 Nov 2017 20:32:21 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH for 2.11 5/5] hw: add .min_cpus and .default_cpus fields to machine_class X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Thomas Huth , Igor Mitsyanko , Richard Henderson , qemu-devel@nongnu.org, Alistair Francis , qemu-arm@nongnu.org, Marcel Apfelbaum , "Edgar E . Iglesias" Errors-To: qemu-devel-bounces+alex.bennee=linaro.org@nongnu.org Sender: "Qemu-devel" X-TUID: f9LwdvP1pKMF On Fri, Nov 10, 2017 at 02:53:46PM -0500, Emilio G. Cota wrote: > max_cpus needs to be an upper bound on the number of vCPUs > initialized; otherwise TCG region initialization breaks. > > Some boards initialize a hard-coded number of vCPUs, which is not > captured by the global max_cpus and therefore breaks TCG initialization. > Fix it by adding the .min_cpus field to machine_class. > > This commit also changes some user-facing behaviour: we now die if > -smp is below this hard-coded vCPU minimum instead of silently > ignoring the passed -smp value (sometimes announcing this by printing > a warning). However, the introduction of .default_cpus lessens the > likelihood that users will notice this: if -smp isn't set, we now > assign the value in .default_cpus to both smp_cpus and max_cpus. IOW, > if a user does not set -smp, they always get a correct number of vCPUs. > > This change fixes 3468b59 ("tcg: enable multiple TCG contexts in > softmmu", 2017-10-24), which broke TCG initialization for some > ARM boards. > > Fixes: 3468b59e18b179bc63c7ce934de912dfa9596122 > Reported-by: Thomas Huth > Suggested-by: Peter Maydell > Signed-off-by: Emilio G. Cota > --- > include/hw/boards.h | 5 +++++ > hw/arm/exynos4_boards.c | 12 ++++-------- > hw/arm/raspi.c | 2 ++ > hw/arm/xlnx-zcu102.c | 2 ++ > vl.c | 21 ++++++++++++++++++--- > 5 files changed, 31 insertions(+), 11 deletions(-) > > diff --git a/include/hw/boards.h b/include/hw/boards.h > index 191a5b3..62f160e 100644 > --- a/include/hw/boards.h > +++ b/include/hw/boards.h > @@ -102,6 +102,9 @@ typedef struct { > > /** > * MachineClass: > + * @max_cpus: maximum number of CPUs supported. Default: 1 > + * @min_cpus: minimum number of CPUs supported. Default: 1 > + * @default_cpus: number of CPUs instantiated if none are specified. Default: 1 > * @get_hotplug_handler: this function is called during bus-less > * device hotplug. If defined it returns pointer to an instance > * of HotplugHandler object, which handles hotplug operation > @@ -167,6 +170,8 @@ struct MachineClass { > BlockInterfaceType block_default_type; > int units_per_default_bus; > int max_cpus; > + int min_cpus; > + int default_cpus; > unsigned int no_serial:1, > no_parallel:1, > use_virtcon:1, > diff --git a/hw/arm/exynos4_boards.c b/hw/arm/exynos4_boards.c > index f1441ec..750162c 100644 > --- a/hw/arm/exynos4_boards.c > +++ b/hw/arm/exynos4_boards.c > @@ -27,7 +27,6 @@ > #include "qemu-common.h" > #include "cpu.h" > #include "sysemu/sysemu.h" > -#include "sysemu/qtest.h" > #include "hw/sysbus.h" > #include "net/net.h" > #include "hw/arm/arm.h" > @@ -129,13 +128,6 @@ exynos4_boards_init_common(MachineState *machine, > Exynos4BoardType board_type) > { > Exynos4BoardState *s = g_new(Exynos4BoardState, 1); > - MachineClass *mc = MACHINE_GET_CLASS(machine); > - > - if (smp_cpus != EXYNOS4210_NCPUS && !qtest_enabled()) { > - error_report("%s board supports only %d CPU cores, ignoring smp_cpus" > - " value", > - mc->name, EXYNOS4210_NCPUS); > - } > > exynos4_board_binfo.ram_size = exynos4_board_ram_size[board_type]; > exynos4_board_binfo.board_id = exynos4_board_id[board_type]; > @@ -189,6 +181,8 @@ static void nuri_class_init(ObjectClass *oc, void *data) > mc->desc = "Samsung NURI board (Exynos4210)"; > mc->init = nuri_init; > mc->max_cpus = EXYNOS4210_NCPUS; > + mc->min_cpus = EXYNOS4210_NCPUS; > + mc->default_cpus = EXYNOS4210_NCPUS; > mc->ignore_memory_transaction_failures = true; > } > > @@ -205,6 +199,8 @@ static void smdkc210_class_init(ObjectClass *oc, void *data) > mc->desc = "Samsung SMDKC210 board (Exynos4210)"; > mc->init = smdkc210_init; > mc->max_cpus = EXYNOS4210_NCPUS; > + mc->min_cpus = EXYNOS4210_NCPUS; > + mc->default_cpus = EXYNOS4210_NCPUS; > mc->ignore_memory_transaction_failures = true; > } > > diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c > index 5941c9f..cd5fa8c 100644 > --- a/hw/arm/raspi.c > +++ b/hw/arm/raspi.c > @@ -167,6 +167,8 @@ static void raspi2_machine_init(MachineClass *mc) > mc->no_floppy = 1; > mc->no_cdrom = 1; > mc->max_cpus = BCM2836_NCPUS; > + mc->min_cpus = BCM2836_NCPUS; > + mc->default_cpus = BCM2836_NCPUS; > mc->default_ram_size = 1024 * 1024 * 1024; > mc->ignore_memory_transaction_failures = true; > }; > diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c > index 190eb69..9631a53 100644 > --- a/hw/arm/xlnx-zcu102.c > +++ b/hw/arm/xlnx-zcu102.c > @@ -189,6 +189,7 @@ static void xlnx_ep108_machine_class_init(ObjectClass *oc, void *data) > mc->units_per_default_bus = 1; > mc->ignore_memory_transaction_failures = true; > mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS; > + mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS; > } > > static const TypeInfo xlnx_ep108_machine_init_typeinfo = { > @@ -246,6 +247,7 @@ static void xlnx_zcu102_machine_class_init(ObjectClass *oc, void *data) > mc->units_per_default_bus = 1; > mc->ignore_memory_transaction_failures = true; > mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS; > + mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS; > } > > static const TypeInfo xlnx_zcu102_machine_init_typeinfo = { > diff --git a/vl.c b/vl.c > index ec29909..7372424 100644 > --- a/vl.c > +++ b/vl.c > @@ -160,8 +160,8 @@ Chardev *virtcon_hds[MAX_VIRTIO_CONSOLES]; > Chardev *sclp_hds[MAX_SCLP_CONSOLES]; > int win2k_install_hack = 0; > int singlestep = 0; > -int smp_cpus = 1; > -unsigned int max_cpus = 1; > +int smp_cpus; > +unsigned int max_cpus; > int smp_cores = 1; > int smp_threads = 1; > int acpi_enabled = 1; > @@ -4327,9 +4327,24 @@ int main(int argc, char **argv, char **envp) > exit(0); > } > > + /* machine_class: default to UP */ > + machine_class->max_cpus = machine_class->max_cpus ?: 1; > + machine_class->min_cpus = machine_class->min_cpus ?: 1; > + machine_class->default_cpus = machine_class->default_cpus ?: 1; This is consistent with the existing code that initialized max_cpus, but I'd prefer to initialize these defaults inside hw/core/machine.c:machine_class_init(). It can be done in a follow-up patch after 2.11, though. > + > + /* default to machine_class->default_cpus */ > + smp_cpus = machine_class->default_cpus; > + max_cpus = machine_class->default_cpus; > + > smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL)); > > - machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to UP */ > + /* sanity-check smp_cpus and max_cpus against machine_class */ > + if (smp_cpus < machine_class->min_cpus) { > + error_report("Invalid SMP CPUs %d. The min CPUs " > + "supported by machine '%s' is %d", smp_cpus, > + machine_class->name, machine_class->min_cpus); > + exit(1); > + } > if (max_cpus > machine_class->max_cpus) { > error_report("Invalid SMP CPUs %d. The max CPUs " > "supported by machine '%s' is %d", max_cpus, Reviewed-by: Eduardo Habkost -- Eduardo From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55244) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eDFyW-00025P-Ry for qemu-devel@nongnu.org; Fri, 10 Nov 2017 15:32:30 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eDFyV-0004eL-F1 for qemu-devel@nongnu.org; Fri, 10 Nov 2017 15:32:28 -0500 Date: Fri, 10 Nov 2017 18:32:13 -0200 From: Eduardo Habkost Message-ID: <20171110203213.GV3111@localhost.localdomain> References: <1510343626-25861-1-git-send-email-cota@braap.org> <1510343626-25861-6-git-send-email-cota@braap.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1510343626-25861-6-git-send-email-cota@braap.org> Subject: Re: [Qemu-devel] [PATCH for 2.11 5/5] hw: add .min_cpus and .default_cpus fields to machine_class List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Emilio G. Cota" Cc: qemu-devel@nongnu.org, Peter Maydell , Richard Henderson , Thomas Huth , qemu-arm@nongnu.org, Igor Mitsyanko , Alistair Francis , "Edgar E . Iglesias" , Marcel Apfelbaum On Fri, Nov 10, 2017 at 02:53:46PM -0500, Emilio G. Cota wrote: > max_cpus needs to be an upper bound on the number of vCPUs > initialized; otherwise TCG region initialization breaks. > > Some boards initialize a hard-coded number of vCPUs, which is not > captured by the global max_cpus and therefore breaks TCG initialization. > Fix it by adding the .min_cpus field to machine_class. > > This commit also changes some user-facing behaviour: we now die if > -smp is below this hard-coded vCPU minimum instead of silently > ignoring the passed -smp value (sometimes announcing this by printing > a warning). However, the introduction of .default_cpus lessens the > likelihood that users will notice this: if -smp isn't set, we now > assign the value in .default_cpus to both smp_cpus and max_cpus. IOW, > if a user does not set -smp, they always get a correct number of vCPUs. > > This change fixes 3468b59 ("tcg: enable multiple TCG contexts in > softmmu", 2017-10-24), which broke TCG initialization for some > ARM boards. > > Fixes: 3468b59e18b179bc63c7ce934de912dfa9596122 > Reported-by: Thomas Huth > Suggested-by: Peter Maydell > Signed-off-by: Emilio G. Cota > --- > include/hw/boards.h | 5 +++++ > hw/arm/exynos4_boards.c | 12 ++++-------- > hw/arm/raspi.c | 2 ++ > hw/arm/xlnx-zcu102.c | 2 ++ > vl.c | 21 ++++++++++++++++++--- > 5 files changed, 31 insertions(+), 11 deletions(-) > > diff --git a/include/hw/boards.h b/include/hw/boards.h > index 191a5b3..62f160e 100644 > --- a/include/hw/boards.h > +++ b/include/hw/boards.h > @@ -102,6 +102,9 @@ typedef struct { > > /** > * MachineClass: > + * @max_cpus: maximum number of CPUs supported. Default: 1 > + * @min_cpus: minimum number of CPUs supported. Default: 1 > + * @default_cpus: number of CPUs instantiated if none are specified. Default: 1 > * @get_hotplug_handler: this function is called during bus-less > * device hotplug. If defined it returns pointer to an instance > * of HotplugHandler object, which handles hotplug operation > @@ -167,6 +170,8 @@ struct MachineClass { > BlockInterfaceType block_default_type; > int units_per_default_bus; > int max_cpus; > + int min_cpus; > + int default_cpus; > unsigned int no_serial:1, > no_parallel:1, > use_virtcon:1, > diff --git a/hw/arm/exynos4_boards.c b/hw/arm/exynos4_boards.c > index f1441ec..750162c 100644 > --- a/hw/arm/exynos4_boards.c > +++ b/hw/arm/exynos4_boards.c > @@ -27,7 +27,6 @@ > #include "qemu-common.h" > #include "cpu.h" > #include "sysemu/sysemu.h" > -#include "sysemu/qtest.h" > #include "hw/sysbus.h" > #include "net/net.h" > #include "hw/arm/arm.h" > @@ -129,13 +128,6 @@ exynos4_boards_init_common(MachineState *machine, > Exynos4BoardType board_type) > { > Exynos4BoardState *s = g_new(Exynos4BoardState, 1); > - MachineClass *mc = MACHINE_GET_CLASS(machine); > - > - if (smp_cpus != EXYNOS4210_NCPUS && !qtest_enabled()) { > - error_report("%s board supports only %d CPU cores, ignoring smp_cpus" > - " value", > - mc->name, EXYNOS4210_NCPUS); > - } > > exynos4_board_binfo.ram_size = exynos4_board_ram_size[board_type]; > exynos4_board_binfo.board_id = exynos4_board_id[board_type]; > @@ -189,6 +181,8 @@ static void nuri_class_init(ObjectClass *oc, void *data) > mc->desc = "Samsung NURI board (Exynos4210)"; > mc->init = nuri_init; > mc->max_cpus = EXYNOS4210_NCPUS; > + mc->min_cpus = EXYNOS4210_NCPUS; > + mc->default_cpus = EXYNOS4210_NCPUS; > mc->ignore_memory_transaction_failures = true; > } > > @@ -205,6 +199,8 @@ static void smdkc210_class_init(ObjectClass *oc, void *data) > mc->desc = "Samsung SMDKC210 board (Exynos4210)"; > mc->init = smdkc210_init; > mc->max_cpus = EXYNOS4210_NCPUS; > + mc->min_cpus = EXYNOS4210_NCPUS; > + mc->default_cpus = EXYNOS4210_NCPUS; > mc->ignore_memory_transaction_failures = true; > } > > diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c > index 5941c9f..cd5fa8c 100644 > --- a/hw/arm/raspi.c > +++ b/hw/arm/raspi.c > @@ -167,6 +167,8 @@ static void raspi2_machine_init(MachineClass *mc) > mc->no_floppy = 1; > mc->no_cdrom = 1; > mc->max_cpus = BCM2836_NCPUS; > + mc->min_cpus = BCM2836_NCPUS; > + mc->default_cpus = BCM2836_NCPUS; > mc->default_ram_size = 1024 * 1024 * 1024; > mc->ignore_memory_transaction_failures = true; > }; > diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c > index 190eb69..9631a53 100644 > --- a/hw/arm/xlnx-zcu102.c > +++ b/hw/arm/xlnx-zcu102.c > @@ -189,6 +189,7 @@ static void xlnx_ep108_machine_class_init(ObjectClass *oc, void *data) > mc->units_per_default_bus = 1; > mc->ignore_memory_transaction_failures = true; > mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS; > + mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS; > } > > static const TypeInfo xlnx_ep108_machine_init_typeinfo = { > @@ -246,6 +247,7 @@ static void xlnx_zcu102_machine_class_init(ObjectClass *oc, void *data) > mc->units_per_default_bus = 1; > mc->ignore_memory_transaction_failures = true; > mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS; > + mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS; > } > > static const TypeInfo xlnx_zcu102_machine_init_typeinfo = { > diff --git a/vl.c b/vl.c > index ec29909..7372424 100644 > --- a/vl.c > +++ b/vl.c > @@ -160,8 +160,8 @@ Chardev *virtcon_hds[MAX_VIRTIO_CONSOLES]; > Chardev *sclp_hds[MAX_SCLP_CONSOLES]; > int win2k_install_hack = 0; > int singlestep = 0; > -int smp_cpus = 1; > -unsigned int max_cpus = 1; > +int smp_cpus; > +unsigned int max_cpus; > int smp_cores = 1; > int smp_threads = 1; > int acpi_enabled = 1; > @@ -4327,9 +4327,24 @@ int main(int argc, char **argv, char **envp) > exit(0); > } > > + /* machine_class: default to UP */ > + machine_class->max_cpus = machine_class->max_cpus ?: 1; > + machine_class->min_cpus = machine_class->min_cpus ?: 1; > + machine_class->default_cpus = machine_class->default_cpus ?: 1; This is consistent with the existing code that initialized max_cpus, but I'd prefer to initialize these defaults inside hw/core/machine.c:machine_class_init(). It can be done in a follow-up patch after 2.11, though. > + > + /* default to machine_class->default_cpus */ > + smp_cpus = machine_class->default_cpus; > + max_cpus = machine_class->default_cpus; > + > smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL)); > > - machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to UP */ > + /* sanity-check smp_cpus and max_cpus against machine_class */ > + if (smp_cpus < machine_class->min_cpus) { > + error_report("Invalid SMP CPUs %d. The min CPUs " > + "supported by machine '%s' is %d", smp_cpus, > + machine_class->name, machine_class->min_cpus); > + exit(1); > + } > if (max_cpus > machine_class->max_cpus) { > error_report("Invalid SMP CPUs %d. The max CPUs " > "supported by machine '%s' is %d", max_cpus, Reviewed-by: Eduardo Habkost -- Eduardo