From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Michael Ellerman <mpe@ellerman.id.au>
Cc: Juergen Gross <jgross@suse.com>,
Nathan Lynch <nathanl@linux.ibm.com>,
Valentin Schneider <vschneid@redhat.com>,
Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
Paul E McKenney <paulmck@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org,
Nicholas Piggin <npiggin@gmail.com>,
linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
Josh Poimboeuf <jpoimboe@kernel.org>
Subject: [PATCH 4/4] powerpc/smp: Disable MC domain for shared processor
Date: Wed, 30 Aug 2023 16:22:44 +0530 [thread overview]
Message-ID: <20230830105244.62477-5-srikar@linux.vnet.ibm.com> (raw)
In-Reply-To: <20230830105244.62477-1-srikar@linux.vnet.ibm.com>
Like L2-cache info, coregroup information which is used to determine MC
sched domains is only present on dedicated LPARs. i.e PowerVM doesn't
export coregroup information for shared processor LPARs. Hence disable
creating MC domains on shared LPAR Systems.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
arch/powerpc/kernel/smp.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 51403640440c..48b8161179a8 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -1036,6 +1036,10 @@ static struct cpumask *cpu_coregroup_mask(int cpu)
static bool has_coregroup_support(void)
{
+ /* Coregroup identification not available on shared systems */
+ if (is_shared_processor())
+ return 0;
+
return coregroup_enabled;
}
--
2.41.0
prev parent reply other threads:[~2023-08-30 10:58 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-30 10:52 [PATCH 0/4] powerpc/smp: Shared processor sched optimizations Srikar Dronamraju
2023-08-30 10:52 ` [PATCH 1/4] powerpc/smp: Cache CPU has Asymmetric SMP Srikar Dronamraju
2023-08-30 10:52 ` [PATCH 2/4] powerpc/smp: Move shared_processor static key to smp.h Srikar Dronamraju
2023-08-30 10:52 ` [PATCH 3/4] powerpc/smp: Enable Asym packing for cores on shared processor Srikar Dronamraju
2023-08-30 10:52 ` Srikar Dronamraju [this message]
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