> -----Original Message----- > From: Stefano Stabellini <sstabell...@kernel.org> > Sent: 2021年9月25日 3:36 > To: Wei Chen <wei.c...@arm.com> > Cc: Stefano Stabellini <sstabell...@kernel.org>; xen- > de...@lists.xenproject.org; jul...@xen.org; Bertrand Marquis > <bertrand.marq...@arm.com> > Subject: RE: [PATCH 23/37] xen/arm: implement node distance helpers for > Arm > > On Fri, 24 Sep 2021, Wei Chen wrote: > > > -----Original Message----- > > > From: Stefano Stabellini <sstabell...@kernel.org> > > > Sent: 2021年9月24日 9:47 > > > To: Wei Chen <wei.c...@arm.com> > > > Cc: xen-devel@lists.xenproject.org; sstabell...@kernel.org; > jul...@xen.org; > > > Bertrand Marquis <bertrand.marq...@arm.com> > > > Subject: Re: [PATCH 23/37] xen/arm: implement node distance helpers > for > > > Arm > > > > > > On Thu, 23 Sep 2021, Wei Chen wrote: > > > > We will parse NUMA nodes distances from device tree or ACPI > > > > table. So we need a matrix to record the distances between > > > > any two nodes we parsed. Accordingly, we provide this > > > > node_set_distance API for device tree or ACPI table parsers > > > > to set the distance for any two nodes in this patch. > > > > When NUMA initialization failed, __node_distance will return > > > > NUMA_REMOTE_DISTANCE, this will help us avoid doing rollback > > > > for distance maxtrix when NUMA initialization failed. > > > > > > > > Signed-off-by: Wei Chen <wei.c...@arm.com> > > > > --- > > > > xen/arch/arm/Makefile | 1 + > > > > xen/arch/arm/numa.c | 69 > ++++++++++++++++++++++++++++++++++++++ > > > > xen/include/asm-arm/numa.h | 13 +++++++ > > > > 3 files changed, 83 insertions(+) > > > > create mode 100644 xen/arch/arm/numa.c > > > > > > > > diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile > > > > index ae4efbf76e..41ca311b6b 100644 > > > > --- a/xen/arch/arm/Makefile > > > > +++ b/xen/arch/arm/Makefile > > > > @@ -35,6 +35,7 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o > > > > obj-y += mem_access.o > > > > obj-y += mm.o > > > > obj-y += monitor.o > > > > +obj-$(CONFIG_NUMA) += numa.o > > > > obj-y += p2m.o > > > > obj-y += percpu.o > > > > obj-y += platform.o > > > > diff --git a/xen/arch/arm/numa.c b/xen/arch/arm/numa.c > > > > new file mode 100644 > > > > index 0000000000..3f08870d69 > > > > --- /dev/null > > > > +++ b/xen/arch/arm/numa.c > > > > @@ -0,0 +1,69 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > +/* > > > > + * Arm Architecture support layer for NUMA. > > > > + * > > > > + * Copyright (C) 2021 Arm Ltd > > > > + * > > > > + * This program is free software; you can redistribute it and/or > modify > > > > + * it under the terms of the GNU General Public License version 2 > as > > > > + * published by the Free Software Foundation. > > > > + * > > > > + * This program is distributed in the hope that it will be useful, > > > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > > > + * GNU General Public License for more details. > > > > + * > > > > + * You should have received a copy of the GNU General Public > License > > > > + * along with this program. If not, see > <http://www.gnu.org/licenses/>. > > > > + * > > > > + */ > > > > +#include <xen/init.h> > > > > +#include <xen/numa.h> > > > > + > > > > +static uint8_t __read_mostly > > > > +node_distance_map[MAX_NUMNODES][MAX_NUMNODES] = { > > > > + { 0 } > > > > +}; > > > > + > > > > +void __init numa_set_distance(nodeid_t from, nodeid_t to, uint32_t > > > distance) > > > > +{ > > > > + if ( from >= MAX_NUMNODES || to >= MAX_NUMNODES ) > > > > + { > > > > + printk(KERN_WARNING > > > > + "NUMA: invalid nodes: from=%"PRIu8" to=%"PRIu8" > > > MAX=%"PRIu8"\n", > > > > + from, to, MAX_NUMNODES); > > > > + return; > > > > + } > > > > + > > > > + /* NUMA defines 0xff as an unreachable node and 0-9 are > undefined > > > */ > > > > + if ( distance >= NUMA_NO_DISTANCE || > > > > + (distance >= NUMA_DISTANCE_UDF_MIN && > > > > + distance <= NUMA_DISTANCE_UDF_MAX) || > > > > + (from == to && distance != NUMA_LOCAL_DISTANCE) ) > > > > + { > > > > + printk(KERN_WARNING > > > > + "NUMA: invalid distance: from=%"PRIu8" to=%"PRIu8" > > > distance=%"PRIu32"\n", > > > > + from, to, distance); > > > > + return; > > > > + } > > > > + > > > > + node_distance_map[from][to] = distance; > > > > +} > > > > + > > > > +uint8_t __node_distance(nodeid_t from, nodeid_t to) > > > > +{ > > > > + /* When NUMA is off, any distance will be treated as remote. */ > > > > + if ( srat_disabled() ) > > > > > > Given that this is ARM specific code and specific to ACPI, I don't > think > > > we should have any call to something called "srat_disabled". > > > > > > I suggest to either rename srat_disabled to numa_distance_disabled. > > > > > > Other than that, this patch looks OK to me. > > > > > > > srat stands for static resource affinity table, I think dtb also can be > > treated as a static resource affinity table. So I keep SRAT in this > patch > > and other patches. I have seen your comment in patch#25. Before x86 > maintainers > > give any feedback, can we still keep srat here? > > Jan and I replied in the other thread. I think that in warning messages > "SRAT" should not be mentioned when booting from DT. Ideally functions > names and variables should be renamed too when shared between ACPI and > DT but it is less critical, and it is fine if you don't do that in the > next version.
Thanks. I'll leave it as it is, if I do not have a better name.
