From 9f3ba362d84786af8e1ab36a32fb337882b8648c Mon Sep 17 00:00:00 2001
From: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Date: Sat, 8 Dec 2018 17:48:27 -0600
Subject: [PATCH] powerpc/pseries: export timebase register sample in lparcfg
References: bsc#1127750
Patch-mainline: v5.1-rc1
Git-commit: 9f3ba362d84786af8e1ab36a32fb337882b8648c
The Processor Utilzation of Resource Registers (PURR) provide an
estimate of resources used by a cpu thread. Section 7.6 in Book III of
the ISA outlines how to calculate the percentage of shared resources
for threads using the ratio of the PURR delta and Timebase Register
delta for a sampled period.
This calculation is currently done erroneously by the lparstat tool
from the powerpc-utils package. This patch exports the current
timebase value after we sample the PURRs and exposes it to userspace
accounting tools via /proc/ppc64/lparcfg.
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/platforms/pseries/lparcfg.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
index 794487313cc8..e73c7e30efe6 100644
--- a/arch/powerpc/platforms/pseries/lparcfg.c
+++ b/arch/powerpc/platforms/pseries/lparcfg.c
@@ -475,6 +475,7 @@ static int pseries_lparcfg_data(struct seq_file *m, void *v)
splpar_dispatch_data(m);
seq_printf(m, "purr=%ld\n", get_purr());
+ seq_printf(m, "tbr=%ld\n", mftb());
} else { /* non SPLPAR case */
seq_printf(m, "system_active_processors=%d\n",
--
2.20.1