diff options
author | Christian Borntraeger <borntraeger@de.ibm.com> | 2016-11-08 09:53:34 +0100 |
---|---|---|
committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2016-12-12 12:12:18 +0100 |
commit | c19805f870c1fa87c69819eb1e18d9c5fc398f58 (patch) | |
tree | 9315f283cb443bea2890f9d714c874f169d73a83 /arch/s390/kernel/perf_cpum_sf.c | |
parent | b4623d4e5b2370fcf1200cbf832aaa53f6e96ef3 (diff) |
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 <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/perf_cpum_sf.c')
-rw-r--r-- | arch/s390/kernel/perf_cpum_sf.c | 27 |
1 files changed, 20 insertions, 7 deletions
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)) |