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cpuidle: pseries: Do not cap the CEDE0 latency in fixup_cede0_latency()
authorGautham R. Shenoy <ego@linux.vnet.ibm.com>
Mon, 19 Jul 2021 06:33:19 +0000 (12:03 +0530)
committerMichael Ellerman <mpe@ellerman.id.au>
Tue, 3 Aug 2021 12:33:37 +0000 (22:33 +1000)
commit71737a6c2a8f801622d2b71567d1ec1e4c5b40b8
tree362fa4c361cc3196cc3c11bb8d161f3f9d7a5502
parent50741b70b0cbbafbd9199f5180e66c0c53783a4a
cpuidle: pseries: Do not cap the CEDE0 latency in fixup_cede0_latency()

Currently in fixup_cede0_latency() code, we perform the fixup the
CEDE(0) exit latency value only if minimum advertized extended CEDE
latency values are less than 10us. This was done so as to not break
the expected behaviour on POWER8 platforms where the advertised
latency was higher than the default 10us, which would delay the SMT
folding on the core.

However, after the earlier patch "cpuidle/pseries: Fixup CEDE0 latency
only for POWER10 onwards", we can be sure that the fixup of CEDE0
latency is going to happen only from POWER10 onwards. Hence
unconditionally use the minimum exit latency provided by the platform.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1626676399-15975-3-git-send-email-ego@linux.vnet.ibm.com
drivers/cpuidle/cpuidle-pseries.c