Messages in this thread Patch in this message | | | From | Hemant Kumar <> | Subject | [PATCH v4 1/2] perf/kvm: Port perf kvm to powerpc | Date | Thu, 21 May 2015 09:25:07 +0530 |
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From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
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@linux.vnet.ibm.com> Signed-off-by: Hemant Kumar <hemant@linux.vnet.ibm.com> --- Changes : - Moved the uapi related changes to arch/powerpc patchset.
This patch has a dependency on : http://www.mail-archive.com/linuxppc-dev@lists.ozlabs.org/msg89485.html which exports the kvm exit reasons.
tools/perf/arch/powerpc/Makefile | 1 + tools/perf/arch/powerpc/util/Build | 1 + tools/perf/arch/powerpc/util/kvm-stat.c | 33 +++++++++++++++++++++++++++++++++ 3 files changed, 35 insertions(+) create mode 100644 tools/perf/arch/powerpc/util/kvm-stat.c
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 diff --git a/tools/perf/arch/powerpc/util/Build b/tools/perf/arch/powerpc/util/Build index 7b8b0d1..c8fe207 100644 --- a/tools/perf/arch/powerpc/util/Build +++ b/tools/perf/arch/powerpc/util/Build @@ -1,5 +1,6 @@ libperf-y += header.o libperf-y += sym-handling.o +libperf-y += kvm-stat.o libperf-$(CONFIG_DWARF) += dwarf-regs.o libperf-$(CONFIG_DWARF) += skip-callchain-idx.o diff --git a/tools/perf/arch/powerpc/util/kvm-stat.c b/tools/perf/arch/powerpc/util/kvm-stat.c new file mode 100644 index 0000000..24e06bf --- /dev/null +++ b/tools/perf/arch/powerpc/util/kvm-stat.c @@ -0,0 +1,33 @@ +#include "../../util/kvm-stat.h" +#include <asm/kvm_perf_book3s.h> + +define_exit_reasons_table(hv_exit_reasons, kvm_trace_symbol_exit); + +static struct kvm_events_ops exit_events = { + .is_begin_event = exit_event_begin, + .is_end_event = exit_event_end, + .decode_key = exit_event_decode_key, + .name = "VM-EXIT" +}; + +const char *const kvm_events_tp[] = { + "kvm_hv:kvm_guest_exit", + "kvm_hv:kvm_guest_enter", + NULL, +}; + +struct kvm_reg_events_ops kvm_reg_events_ops[] = { + { .name = "vmexit", .ops = &exit_events }, + { NULL, NULL }, +}; + +const char * const kvm_skip_events[] = { + NULL, +}; + +int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid __maybe_unused) +{ + kvm->exit_reasons = hv_exit_reasons; + kvm->exit_reasons_isa = "HV"; + return 0; +} -- 1.9.3
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