From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Michael Ellerman <michaele@au1.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
LKML <linux-kernel@vger.kernel.org>,
Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Valentin Schneider <valentin.schneider@arm.com>,
Nick Piggin <npiggin@au1.ibm.com>,
Oliver OHalloran <oliveroh@au1.ibm.com>,
Nathan Lynch <nathanl@linux.ibm.com>,
Michael Neuling <mikey@linux.ibm.com>,
Anton Blanchard <anton@au1.ibm.com>,
Gautham R Shenoy <ego@linux.vnet.ibm.com>,
Vaidyanathan Srinivasan <svaidy@linux.ibm.com>,
Jordan Niethe <jniethe5@gmail.com>
Subject: [PATCH v2 10/10] powerpc/smp: Implement cpu_to_coregroup_id
Date: Tue, 21 Jul 2020 17:08:14 +0530 [thread overview]
Message-ID: <20200721113814.32284-11-srikar@linux.vnet.ibm.com> (raw)
In-Reply-To: <20200721113814.32284-1-srikar@linux.vnet.ibm.com>
Lookup the coregroup id from the associativity array.
If unable to detect the coregroup id, fallback on the core id.
This way, ensure sched_domain degenerates and an extra sched domain is
not created.
Ideally this function should have been implemented in
arch/powerpc/kernel/smp.c. However if its implemented in mm/numa.c, we
don't need to find the primary domain again.
If the device-tree mentions more than one coregroup, then kernel
implements only the last or the smallest coregroup, which currently
corresponds to the penultimate domain in the device-tree.
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Michael Ellerman <michaele@au1.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Nick Piggin <npiggin@au1.ibm.com>
Cc: Oliver OHalloran <oliveroh@au1.ibm.com>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: Michael Neuling <mikey@linux.ibm.com>
Cc: Anton Blanchard <anton@au1.ibm.com>
Cc: Gautham R Shenoy <ego@linux.vnet.ibm.com>
Cc: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Cc: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
Changelog v1 -> v2:
powerpc/smp: Implement cpu_to_coregroup_id
Move coregroup_enabled before getting associativity (Gautham)
arch/powerpc/mm/numa.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index ef8aa580da21..ae57b68beaee 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1218,6 +1218,26 @@ int find_and_online_cpu_nid(int cpu)
int cpu_to_coregroup_id(int cpu)
{
+ __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
+ int index;
+
+ if (cpu < 0 || cpu > nr_cpu_ids)
+ return -1;
+
+ if (!coregroup_enabled)
+ goto out;
+
+ if (!firmware_has_feature(FW_FEATURE_VPHN))
+ goto out;
+
+ if (vphn_get_associativity(cpu, associativity))
+ goto out;
+
+ index = of_read_number(associativity, 1);
+ if (index > min_common_depth + 1)
+ return of_read_number(&associativity[index - 1], 1);
+
+out:
return cpu_to_core_id(cpu);
}
--
2.17.1
next prev parent reply other threads:[~2020-07-21 11:39 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-21 11:38 [PATCH v2 00/10] Coregroup support on Powerpc Srikar Dronamraju
2020-07-21 11:38 ` [PATCH v2 01/10] powerpc/smp: Cache node for reuse Srikar Dronamraju
2020-07-22 7:41 ` Michael Ellerman
2020-07-22 8:04 ` Srikar Dronamraju
2020-07-21 11:38 ` [PATCH v2 02/10] powerpc/smp: Merge Power9 topology with Power topology Srikar Dronamraju
2020-07-22 5:48 ` Gautham R Shenoy
2020-07-21 11:38 ` [PATCH v2 03/10] powerpc/smp: Move powerpc_topology above Srikar Dronamraju
2020-07-21 11:38 ` [PATCH v2 04/10] powerpc/smp: Enable small core scheduling sooner Srikar Dronamraju
2020-07-22 5:59 ` Gautham R Shenoy
2020-07-22 6:59 ` Srikar Dronamraju
2020-07-21 11:38 ` [PATCH v2 05/10] powerpc/smp: Dont assume l2-cache to be superset of sibling Srikar Dronamraju
2020-07-22 6:21 ` Gautham R Shenoy
2020-07-22 6:57 ` Srikar Dronamraju
2020-07-24 7:10 ` Gautham R Shenoy
2020-07-21 11:38 ` [PATCH v2 06/10] powerpc/smp: Generalize 2nd sched domain Srikar Dronamraju
2020-07-22 6:56 ` Gautham R Shenoy
2020-07-22 7:39 ` Srikar Dronamraju
2020-07-22 7:46 ` peterz
2020-07-22 8:18 ` Srikar Dronamraju
2020-07-22 8:48 ` Peter Zijlstra
2020-07-22 8:54 ` peterz
2020-07-21 11:38 ` [PATCH v2 07/10] Powerpc/numa: Detect support for coregroup Srikar Dronamraju
2020-07-21 11:38 ` [PATCH v2 08/10] powerpc/smp: Allocate cpumask only after searching thread group Srikar Dronamraju
2020-07-21 11:38 ` [PATCH v2 09/10] Powerpc/smp: Create coregroup domain Srikar Dronamraju
2020-07-22 7:04 ` Gautham R Shenoy
2020-07-22 7:29 ` Srikar Dronamraju
2020-07-21 11:38 ` Srikar Dronamraju [this message]
2020-07-22 7:06 ` [PATCH v2 10/10] powerpc/smp: Implement cpu_to_coregroup_id Gautham R Shenoy
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