From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e28smtp08.in.ibm.com (e28smtp08.in.ibm.com [122.248.162.8]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp08.in.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id EBA3E2C0177 for ; Thu, 25 Jul 2013 01:00:31 +1000 (EST) Received: from /spool/local by e28smtp08.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 24 Jul 2013 20:20:25 +0530 Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by d28dlp03.in.ibm.com (Postfix) with ESMTP id AB8061258051 for ; Wed, 24 Jul 2013 20:29:39 +0530 (IST) Received: from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63]) by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r6OF17TH30933082 for ; Wed, 24 Jul 2013 20:31:07 +0530 Received: from d28av01.in.ibm.com (loopback [127.0.0.1]) by d28av01.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r6OF08Lg003933 for ; Wed, 24 Jul 2013 15:00:12 GMT Date: Wed, 24 Jul 2013 10:00:05 -0500 From: Robert Jennings To: linuxppc-dev@lists.ozlabs.org, Benjamin Herrenschmidt , Paul Mackerras , Nathan Fontenot , Robert Jennings , Michael Ellerman , Jan Stancek , stable@vger.kernel.org Subject: [PATCH v2] powerpc: VPHN topology change updates all siblings Message-ID: <20130724150005.GB13737@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , When an associativity level change is found for one thread, the siblings threads need to be updated as well. This is done today for PRRN in stage_topology_update() but is missing for VPHN in update_cpu_associativity_changes_mask(). All threads should be updated to move to the new node. Without this patch, a single thread may be flagged for a topology change, leaving it in a different node from its siblings, which is incorrect. This causes problems for the scheduler where overlapping scheduler groups are created and a loop is formed in those groups. Signed-off-by: Robert Jennings --- cpu_sibling_mask is now defined for UP which fixes that build break. --- arch/powerpc/include/asm/smp.h | 4 +++ arch/powerpc/mm/numa.c | 59 +++++++++++++++++++++++++++++++----------- 2 files changed, 48 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h index ffbaabe..48cfc85 100644 --- a/arch/powerpc/include/asm/smp.h +++ b/arch/powerpc/include/asm/smp.h @@ -145,6 +145,10 @@ extern void __cpu_die(unsigned int cpu); #define smp_setup_cpu_maps() static inline void inhibit_secondary_onlining(void) {} static inline void uninhibit_secondary_onlining(void) {} +static inline const struct cpumask *cpu_sibling_mask(int cpu) +{ + return cpumask_of(cpu); +} #endif /* CONFIG_SMP */ diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 0839721..5850798 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -1318,7 +1319,8 @@ static int update_cpu_associativity_changes_mask(void) } } if (changed) { - cpumask_set_cpu(cpu, changes); + cpumask_or(changes, changes, cpu_sibling_mask(cpu)); + cpu = cpu_last_thread_sibling(cpu); } } @@ -1426,7 +1428,7 @@ static int update_cpu_topology(void *data) if (!data) return -EINVAL; - cpu = get_cpu(); + cpu = smp_processor_id(); for (update = data; update; update = update->next) { if (cpu != update->cpu) @@ -1446,12 +1448,12 @@ static int update_cpu_topology(void *data) */ int arch_update_cpu_topology(void) { - unsigned int cpu, changed = 0; + unsigned int cpu, sibling, changed = 0; struct topology_update_data *updates, *ud; unsigned int associativity[VPHN_ASSOC_BUFSIZE] = {0}; cpumask_t updated_cpus; struct device *dev; - int weight, i = 0; + int weight, new_nid, i = 0; weight = cpumask_weight(&cpu_associativity_changes_mask); if (!weight) @@ -1464,19 +1466,46 @@ int arch_update_cpu_topology(void) cpumask_clear(&updated_cpus); for_each_cpu(cpu, &cpu_associativity_changes_mask) { - ud = &updates[i++]; - ud->cpu = cpu; - vphn_get_associativity(cpu, associativity); - ud->new_nid = associativity_to_nid(associativity); - - if (ud->new_nid < 0 || !node_online(ud->new_nid)) - ud->new_nid = first_online_node; + /* + * If siblings aren't flagged for changes, updates list + * will be too short. Skip on this update and set for next + * update. + */ + if (!cpumask_subset(cpu_sibling_mask(cpu), + &cpu_associativity_changes_mask)) { + pr_info("Sibling bits not set for associativity " + "change, cpu%d\n", cpu); + cpumask_or(&cpu_associativity_changes_mask, + &cpu_associativity_changes_mask, + cpu_sibling_mask(cpu)); + cpu = cpu_last_thread_sibling(cpu); + continue; + } - ud->old_nid = numa_cpu_lookup_table[cpu]; - cpumask_set_cpu(cpu, &updated_cpus); + /* Use associativity from first thread for all siblings */ + vphn_get_associativity(cpu, associativity); + new_nid = associativity_to_nid(associativity); + if (new_nid < 0 || !node_online(new_nid)) + new_nid = first_online_node; + + if (new_nid == numa_cpu_lookup_table[cpu]) { + cpumask_andnot(&cpu_associativity_changes_mask, + &cpu_associativity_changes_mask, + cpu_sibling_mask(cpu)); + cpu = cpu_last_thread_sibling(cpu); + continue; + } - if (i < weight) - ud->next = &updates[i]; + for_each_cpu(sibling, cpu_sibling_mask(cpu)) { + ud = &updates[i++]; + ud->cpu = sibling; + ud->new_nid = new_nid; + ud->old_nid = numa_cpu_lookup_table[sibling]; + cpumask_set_cpu(sibling, &updated_cpus); + if (i < weight) + ud->next = &updates[i]; + } + cpu = cpu_last_thread_sibling(cpu); } stop_machine(update_cpu_topology, &updates[0], &updated_cpus); -- 1.8.1.2