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author | Hendrik Brueckner <brueckner@linux.vnet.ibm.com> | 2013-12-12 17:54:57 +0100 |
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committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2013-12-16 14:37:59 +0100 |
commit | 443e802bab16916f9a51a34f2213f4dee6e8762c (patch) | |
tree | 8481d35917b96ad1dfee837e52ad804e3459e018 /arch/s390/kernel/perf_event.c | |
parent | 443d4beb823d4dccaaf964b59df9dd38b4d6aae7 (diff) | |
download | linux-443e802bab16916f9a51a34f2213f4dee6e8762c.tar.bz2 |
s390/cpum_sf: Detect KVM guest samples
The host-program-parameter (hpp) value of basic sample-data-entries designates
a SIE control block that is set by the LPP instruction in sie64a().
Non-zero values indicate guest samples, a value of zero indicates a host sample.
For perf samples, host and guest samples are distinguished using particular
PERF_MISC_* flags. The perf layer calls perf_misc_flags() to set the flags
based on the pt_regs content. For each sample-data-entry, the cpum_sf PMU
creates a pt_regs structure with the sample-data information. An additional
flag structure is added to easily distinguish between host and guest samples.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/perf_event.c')
-rw-r--r-- | arch/s390/kernel/perf_event.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/arch/s390/kernel/perf_event.c b/arch/s390/kernel/perf_event.c index 3bd2bf030ad4..60a68261d091 100644 --- a/arch/s390/kernel/perf_event.c +++ b/arch/s390/kernel/perf_event.c @@ -1,7 +1,7 @@ /* * Performance event support for s390x * - * Copyright IBM Corp. 2012 + * Copyright IBM Corp. 2012, 2013 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> * * This program is free software; you can redistribute it and/or modify @@ -89,8 +89,31 @@ static unsigned long perf_misc_guest_flags(struct pt_regs *regs) : PERF_RECORD_MISC_GUEST_KERNEL; } +static unsigned long perf_misc_flags_sf(struct pt_regs *regs) +{ + struct perf_sf_sde_regs *sde_regs; + unsigned long flags; + + sde_regs = (struct perf_sf_sde_regs *) ®s->int_parm_long; + if (sde_regs->in_guest) + flags = user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER + : PERF_RECORD_MISC_GUEST_KERNEL; + else + flags = user_mode(regs) ? PERF_RECORD_MISC_USER + : PERF_RECORD_MISC_KERNEL; + return flags; +} + unsigned long perf_misc_flags(struct pt_regs *regs) { + /* Check if the cpum_sf PMU has created the pt_regs structure. + * In this case, perf misc flags can be easily extracted. Otherwise, + * do regular checks on the pt_regs content. + */ + if (regs->int_code == 0x1407 && regs->int_parm == CPU_MF_INT_SF_PRA) + if (!regs->gprs[15]) + return perf_misc_flags_sf(regs); + if (is_in_guest(regs)) return perf_misc_guest_flags(regs); |