Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756018AbZKMKC1 (ORCPT ); Fri, 13 Nov 2009 05:02:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755781AbZKMKCX (ORCPT ); Fri, 13 Nov 2009 05:02:23 -0500 Received: from smtp-out.google.com ([216.239.33.17]:20346 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755932AbZKMKCW (ORCPT ); Fri, 13 Nov 2009 05:02:22 -0500 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id: references:user-agent:mime-version:content-type:x-system-of-record; b=Uj/4wTrbMduc9b7/nfqxeFAsIdNOo2e5E0fXuwg3dFRDcas38q7rJPmyo8Flg5TU0 56a1bUfPClk+oi7An/meg== Date: Fri, 13 Nov 2009 02:02:17 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Ingo Molnar cc: Thomas Gleixner , Andrew Morton , Mike Travis , Heiko Carstens , Roland Dreier , Randy Dunlap , Tejun Heo , Andi Kleen , Greg Kroah-Hartman , Yinghai Lu , "H. Peter Anvin" , Steven Rostedt , Rusty Russell , Hidetoshi Seto , Jack Steiner , Frederic Weisbecker , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [patch] x86: reduce srat verbosity in the kernel log In-Reply-To: <20091113095350.GC1364@elte.hu> Message-ID: References: <20091112171934.584037000@alcatraz.americas.sgi.com> <20091113095350.GC1364@elte.hu> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4605 Lines: 121 On Fri, 13 Nov 2009, Ingo Molnar wrote: > > It's possible to reduce the number of SRAT messages emitted to the kernel > > log by printing each valid pxm once and then creating bitmaps to represent > > the apic ids that map to the same node. > > > > This reduces lines such as > > > > SRAT: PXM 0 -> APIC 0 -> Node 0 > > SRAT: PXM 0 -> APIC 1 -> Node 0 > > SRAT: PXM 1 -> APIC 2 -> Node 1 > > SRAT: PXM 1 -> APIC 3 -> Node 1 > > > > to > > > > SRAT: PXM 0 -> APIC {0-1} -> Node 0 > > SRAT: PXM 1 -> APIC {2-3} -> Node 1 > > > > The buffer used to store the apic id list is 128 characters in length. > > If that is too small to represent all the apic id ranges that are bound > > to a single pxm, a trailing "..." is added. APICID_LIST_LEN should be > > manually increased for such configurations. > > > > Acked-by: Mike Travis > > Signed-off-by: David Rientjes > > --- > > arch/x86/mm/srat_64.c | 41 +++++++++++++++++++++++++++++++++++++---- > > drivers/acpi/numa.c | 5 +++++ > > include/linux/acpi.h | 3 ++- > > 3 files changed, 44 insertions(+), 5 deletions(-) > > > > diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c > > --- a/arch/x86/mm/srat_64.c > > +++ b/arch/x86/mm/srat_64.c > > @@ -36,6 +36,9 @@ static int num_node_memblks __initdata; > > static struct bootnode node_memblk_range[NR_NODE_MEMBLKS] __initdata; > > static int memblk_nodeid[NR_NODE_MEMBLKS] __initdata; > > > > +static DECLARE_BITMAP(apicid_map, MAX_LOCAL_APIC) __initdata; > > +#define APICID_LIST_LEN (128) > > + > > static __init int setup_node(int pxm) > > { > > return acpi_map_pxm_to_node(pxm); > > @@ -136,8 +139,6 @@ acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa) > > apicid_to_node[apic_id] = node; > > node_set(node, cpu_nodes_parsed); > > acpi_numa = 1; > > - printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n", > > - pxm, apic_id, node); > > } > > > > /* Callback for Proximity Domain -> LAPIC mapping */ > > @@ -170,8 +171,40 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa) > > apicid_to_node[apic_id] = node; > > node_set(node, cpu_nodes_parsed); > > acpi_numa = 1; > > - printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n", > > - pxm, apic_id, node); > > +} > > + > > +void __init acpi_numa_print_srat_mapping(void) > > +{ > > + char apicid_list[APICID_LIST_LEN]; > > + int i, j; > > + > > + for (i = 0; i < MAX_PXM_DOMAINS; i++) { > > + int len; > > + int nid; > > + > > + nid = pxm_to_node(i); > > + if (nid == NUMA_NO_NODE) > > + continue; > > + > > + bitmap_zero(apicid_map, MAX_LOCAL_APIC); > > + for (j = 0; j < MAX_LOCAL_APIC; j++) > > + if (apicid_to_node[j] == nid) > > + set_bit(j, apicid_map); > > + > > + if (bitmap_empty(apicid_map, MAX_LOCAL_APIC)) > > + continue; > > + > > + /* > > + * If the bitmap cannot be listed in a buffer of length > > + * APICID_LIST_LEN, then it is suffixed with "...". > > + */ > > + len = bitmap_scnlistprintf(apicid_list, APICID_LIST_LEN, > > + apicid_map, MAX_LOCAL_APIC); > > + pr_info("SRAT: PXM %u -> APIC {%s%s} -> Node %u\n", > > + i, apicid_list, > > + (len == APICID_LIST_LEN - 1) ? "..." : "", > > + nid); > > + } > > } > > No. As i suggested many times before, just get rid of the printouts or > make them boot-debug-flag dependent. > Hmm, so even if these were dependent on a kernel parameter, do you think this patch would still be needed exactly as it is written? In other words, do you believe that Mark's system should really emit 1272 lines for this data instead of the 40 with this patch? I'm all for making this dependent on a kernel parameter, but it's a seperate change than what this patch is addressing. We need the apic id mappings because they aren't exposed to userspace in any other way, they need to exported somehow and this is a clear improvement to reduce verbosity in the kernel log. So I really don't know what you're insisting here, you want this compression to be accompanied by another patch which makes the call to acpi_numa_print_srat_mapping() depend on a kernel parameter? Or are you saying we shouldn't compress it at all and Mike should just deal with 1272 lines instead of 40? Or are you saying we should export this static information via sysfs? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/