On Fri, 2015-05-08 at 06:37 +0530, Hemant Kumar wrote: > From: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> > > perf kvm can be used to analyze guest exit reasons. This support already > exists in x86. Hence, porting it to powerpc. > > - To trace KVM events : > perf kvm stat record > If many guests are running, we can track for a specific guest by using > --pid as in : perf kvm stat record --pid <pid> > > - To see the results : > perf kvm stat report > > The result shows the number of exits (from the guest context to > host/hypervisor context) grouped by their respective exit reasons with > their frequency. > > This patch makes use of the guest exit reasons available in > "trace_book3s.h". It records on two already available tracepoints : > "kvm_hv:kvm_guest_exit" and "kvm_hv:kvm_guest_enter". > > Note : This patch has a dependency on the patch "kvm/powerpc: Export > kvm exit reasons" which exports the KVM exit reasons through the uapi. > > Here is a sample o/p: > # pgrep qemu > 19378 > 60515 > > 2 Guests are running on the host. > > # perf kvm stat record -a > ^C[ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 4.153 MB perf.data.guest (39624 samples) ] > > # perf kvm stat report -p 60515 > Analyze events for pid(s) 60515, all VCPUs: > > VM-EXIT Samples Samples% Time% Min Time Max Time Avg time > > H_DATA_STORAGE 5006 35.30% 0.13% 1.94us 49.46us 12.37us ( +- 0.52% ) > HV_DECREMENTER 4457 31.43% 0.02% 0.72us 16.14us 1.91us ( +- 0.96% ) > SYSCALL 2690 18.97% 0.10% 2.84us 528.24us 18.29us ( +- 3.75% ) > RETURN_TO_HOST 1789 12.61% 99.76% 1.58us 672791.91us 27470.23us ( +- 3.00% ) > EXTERNAL 240 1.69% 0.00% 0.69us 10.67us 1.33us ( +- 5.34% ) > > Total Samples:14182, Total events handled time:49264158.30us. > > Signed-off-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Hemant Kumar <hemant@xxxxxxxxxxxxxxxxxx> > --- > Patch has a dependency on : https://patchwork.ozlabs.org/patch/469839/ > which exports the exit reasons to perf through uapi. > > Changes: > - Original series split into two patchsets now : perf and powerpc > side changes. > > arch/powerpc/include/uapi/asm/kvm_perf.h | 15 +++++++++++++++ > tools/perf/arch/powerpc/Makefile | 1 + > tools/perf/arch/powerpc/util/Build | 1 + > tools/perf/arch/powerpc/util/kvm-stat.c | 33 ++++++++++++++++++++++++++++++++ > 4 files changed, 50 insertions(+) > create mode 100644 arch/powerpc/include/uapi/asm/kvm_perf.h > create mode 100644 tools/perf/arch/powerpc/util/kvm-stat.c > > diff --git a/arch/powerpc/include/uapi/asm/kvm_perf.h b/arch/powerpc/include/uapi/asm/kvm_perf.h > new file mode 100644 > index 0000000..30fa670 > --- /dev/null > +++ b/arch/powerpc/include/uapi/asm/kvm_perf.h > @@ -0,0 +1,15 @@ > +#ifndef _ASM_POWERPC_KVM_PERF_H > +#define _ASM_POWERPC_KVM_PERF_H > + > +#include <asm/trace_book3s.h> > +#include <asm/kvm.h> > + > +#define DECODE_STR_LEN 20 > + > +#define VCPU_ID "vcpu_id" > + > +#define KVM_ENTRY_TRACE "kvm_hv:kvm_guest_enter" > +#define KVM_EXIT_TRACE "kvm_hv:kvm_guest_exit" > +#define KVM_EXIT_REASON "trap" > + > +#endif /* _ASM_POWERPC_KVM_PERF_H */ Please make sure that anything book3s-specific is named that way. And shouldn't this be part of the arch/powerpc-side patchset? > diff --git a/tools/perf/arch/powerpc/Makefile b/tools/perf/arch/powerpc/Makefile > index 7fbca17..21322e0 100644 > --- a/tools/perf/arch/powerpc/Makefile > +++ b/tools/perf/arch/powerpc/Makefile > @@ -1,3 +1,4 @@ > ifndef NO_DWARF > PERF_HAVE_DWARF_REGS := 1 > endif > +HAVE_KVM_STAT_SUPPORT := 1 Does this stuff fail gracefully if used on a PPC target that doesn't support this? -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
