From c19805f870c1fa87c69819eb1e18d9c5fc398f58 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 8 Nov 2016 09:53:34 +0100 Subject: [PATCH] s390/cpumf: Use configuration level indication for sampling data Newer hardware provides the level of virtualization that a particular sample belongs to. Use that information and fall back to the old heuristics if the sample does not contain that information. Reviewed-by: Heiko Carstens Reviewed-by: Hendrik Brueckner Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/cpu_mf.h | 3 ++- arch/s390/kernel/perf_cpum_sf.c | 27 ++++++++++++++++++++------- 2 files changed, 22 insertions(+), 8 deletions(-) diff --git a/arch/s390/include/asm/cpu_mf.h b/arch/s390/include/asm/cpu_mf.h index 03516476127b..b69d8bc231a5 100644 --- a/arch/s390/include/asm/cpu_mf.h +++ b/arch/s390/include/asm/cpu_mf.h @@ -104,7 +104,8 @@ struct hws_basic_entry { unsigned int P:1; /* 28 PSW Problem state */ unsigned int AS:2; /* 29-30 PSW address-space control */ unsigned int I:1; /* 31 entry valid or invalid */ - unsigned int:16; + unsigned int CL:2; /* 32-33 Configuration Level */ + unsigned int:14; unsigned int prim_asn:16; /* primary ASN */ unsigned long long ia; /* Instruction Address */ unsigned long long gpp; /* Guest Program Parameter */ diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c index 4e7ee8647b8b..763dec18edcd 100644 --- a/arch/s390/kernel/perf_cpum_sf.c +++ b/arch/s390/kernel/perf_cpum_sf.c @@ -1002,16 +1002,29 @@ static int perf_push_sample(struct perf_event *event, struct sf_raw_sample *sfr) psw_bits(regs.psw).as = sfr->basic.AS; /* - * A non-zero guest program parameter indicates a guest - * sample. - * Note that some early samples or samples from guests without + * Use the hardware provided configuration level to decide if the + * sample belongs to a guest or host. If that is not available, + * fall back to the following heuristics: + * A non-zero guest program parameter always indicates a guest + * sample. Some early samples or samples from guests without * lpp usage would be misaccounted to the host. We use the asn - * value as a heuristic to detect most of these guest samples. - * If the value differs from the host hpp value, we assume - * it to be a KVM guest. + * value as an addon heuristic to detect most of these guest samples. + * If the value differs from the host hpp value, we assume to be a + * KVM guest. */ - if (sfr->basic.gpp || sfr->basic.prim_asn != (u16) sfr->basic.hpp) + switch (sfr->basic.CL) { + case 1: /* logical partition */ + sde_regs->in_guest = 0; + break; + case 2: /* virtual machine */ sde_regs->in_guest = 1; + break; + default: /* old machine, use heuristics */ + if (sfr->basic.gpp || + sfr->basic.prim_asn != (u16)sfr->basic.hpp) + sde_regs->in_guest = 1; + break; + } overflow = 0; if (perf_exclude_event(event, ®s, sde_regs)) -- 2.39.2