Re: [PATCH v3 2/2] perf kvm/riscv: Port perf kvm stat to RISC-V

[Anup Patel]

On Fri, Jun 7, 2024 at 7:44 AM Shenlin Liang
<liangshenlin@xxxxxxxxxxxxxxxxxx> wrote:
>
>
> On 2024-06-07 08:27, Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
>
> >
> > Hello,
> >
> > On Mon, Apr 22, 2024 at 08:08:33AM +0000, Shenlin Liang wrote:
> > > 'perf kvm stat report/record' generates a statistical analysis of KVM
> > > events and can be used to analyze guest exit reasons.
> > >
> > > "report" reports statistical analysis of guest exit events.
> > >
> > > To record kvm events on the host:
> > >  # perf kvm stat record -a
> > >
> > > To report kvm VM EXIT events:
> > >  # perf kvm stat report --event=vmexit
> > >
> > > Signed-off-by: Shenlin Liang <liangshenlin@xxxxxxxxxxxxxxxxxx>
> > > ---
> > >  tools/perf/arch/riscv/Makefile                |  1 +
> > >  tools/perf/arch/riscv/util/Build              |  1 +
> > >  tools/perf/arch/riscv/util/kvm-stat.c         | 79 +++++++++++++++++++
> > >  .../arch/riscv/util/riscv_exception_types.h   | 35 ++++++++
> > >  4 files changed, 116 insertions(+)
> > >  create mode 100644 tools/perf/arch/riscv/util/kvm-stat.c
> > >  create mode 100644 tools/perf/arch/riscv/util/riscv_exception_types.h
> > >
> > > diff --git a/tools/perf/arch/riscv/Makefile b/tools/perf/arch/riscv/Makefile
> > > index a8d25d005207..e1e445615536 100644
> > > --- a/tools/perf/arch/riscv/Makefile
> > > +++ b/tools/perf/arch/riscv/Makefile
> > > @@ -3,3 +3,4 @@ PERF_HAVE_DWARF_REGS := 1
> > >  endif
> > >  PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1
> > >  PERF_HAVE_JITDUMP := 1
> > > +HAVE_KVM_STAT_SUPPORT := 1
> > > \ No newline at end of file
> > > diff --git a/tools/perf/arch/riscv/util/Build b/tools/perf/arch/riscv/util/Build
> > > index 603dbb5ae4dc..d72b04f8d32b 100644
> > > --- a/tools/perf/arch/riscv/util/Build
> > > +++ b/tools/perf/arch/riscv/util/Build
> > > @@ -1,5 +1,6 @@
> > >  perf-y += perf_regs.o
> > >  perf-y += header.o
> > >
> > > +perf-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o
> > >  perf-$(CONFIG_DWARF) += dwarf-regs.o
> > >  perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
> > > diff --git a/tools/perf/arch/riscv/util/kvm-stat.c b/tools/perf/arch/riscv/util/kvm-stat.c
> > > new file mode 100644
> > > index 000000000000..58813049fc45
> > > --- /dev/null
> > > +++ b/tools/perf/arch/riscv/util/kvm-stat.c
> > > @@ -0,0 +1,79 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * Arch specific functions for perf kvm stat.
> > > + *
> > > + * Copyright 2024 Beijing ESWIN Computing Technology Co., Ltd.
> > > + *
> > > + */
> > > +#include <errno.h>
> > > +#include <memory.h>
> > > +#include "../../../util/evsel.h"
> > > +#include "../../../util/kvm-stat.h"
> > > +#include "riscv_exception_types.h"
> > > +#include "debug.h"
> > > +
> > > +define_exit_reasons_table(riscv_exit_reasons, kvm_riscv_exception_class);
> > > +
> > > +const char *vcpu_id_str = "id";
> > > +const char *kvm_exit_reason = "scause";
> > > +const char *kvm_entry_trace = "kvm:kvm_entry";
> > > +const char *kvm_exit_trace = "kvm:kvm_exit";
> > > +
> > > +const char *kvm_events_tp[] = {
> > > +   "kvm:kvm_entry",
> > > +   "kvm:kvm_exit",
> > > +   NULL,
> > > +};
> > > +
> > > +static void event_get_key(struct evsel *evsel,
> > > +                     struct perf_sample *sample,
> > > +                     struct event_key *key)
> > > +{
> > > +   key->info = 0;
> > > +   key->key = evsel__intval(evsel, sample, kvm_exit_reason);
> > > +   key->key = (int)key->key;
> >
> > Looks unnecessary..
> >
> > Thanks,
> > Namhyung
>
> Yes，it's unnecessary...
> @Anup, Could you delete this line when merging, or should I send another revision ?

No need for another revision, I have updated the riscv_kvm_queue.

Regards,
Anup

> Thanks,
> Shenlin
>
> >
> >
> > > +   key->exit_reasons = riscv_exit_reasons;
> > > +}
> > > +
> > > +static bool event_begin(struct evsel *evsel,
> > > +                   struct perf_sample *sample __maybe_unused,
> > > +                   struct event_key *key __maybe_unused)
> > > +{
> > > +   return evsel__name_is(evsel, kvm_entry_trace);
> > > +}
> > > +
> > > +static bool event_end(struct evsel *evsel,
> > > +                 struct perf_sample *sample,
> > > +                 struct event_key *key)
> > > +{
> > > +   if (evsel__name_is(evsel, kvm_exit_trace)) {
> > > +           event_get_key(evsel, sample, key);
> > > +           return true;
> > > +   }
> > > +   return false;
> > > +}
> > > +
> > > +static struct kvm_events_ops exit_events = {
> > > +   .is_begin_event = event_begin,
> > > +   .is_end_event   = event_end,
> > > +   .decode_key     = exit_event_decode_key,
> > > +   .name           = "VM-EXIT"
> > > +};
> > > +
> > > +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_isa = "riscv64";
> > > +   return 0;
> > > +}
> > > diff --git a/tools/perf/arch/riscv/util/riscv_exception_types.h b/tools/perf/arch/riscv/util/riscv_exception_types.h
> > > new file mode 100644
> > > index 000000000000..c49b8fa5e847
> > > --- /dev/null
> > > +++ b/tools/perf/arch/riscv/util/riscv_exception_types.h
> > > @@ -0,0 +1,35 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +#ifndef ARCH_PERF_RISCV_EXCEPTION_TYPES_H
> > > +#define ARCH_PERF_RISCV_EXCEPTION_TYPES_H
> > > +
> > > +#define EXC_INST_MISALIGNED 0
> > > +#define EXC_INST_ACCESS 1
> > > +#define EXC_INST_ILLEGAL 2
> > > +#define EXC_BREAKPOINT 3
> > > +#define EXC_LOAD_MISALIGNED 4
> > > +#define EXC_LOAD_ACCESS 5
> > > +#define EXC_STORE_MISALIGNED 6
> > > +#define EXC_STORE_ACCESS 7
> > > +#define EXC_SYSCALL 8
> > > +#define EXC_HYPERVISOR_SYSCALL 9
> > > +#define EXC_SUPERVISOR_SYSCALL 10
> > > +#define EXC_INST_PAGE_FAULT 12
> > > +#define EXC_LOAD_PAGE_FAULT 13
> > > +#define EXC_STORE_PAGE_FAULT 15
> > > +#define EXC_INST_GUEST_PAGE_FAULT 20
> > > +#define EXC_LOAD_GUEST_PAGE_FAULT 21
> > > +#define EXC_VIRTUAL_INST_FAULT 22
> > > +#define EXC_STORE_GUEST_PAGE_FAULT 23
> > > +
> > > +#define EXC(x) {EXC_##x, #x }
> > > +
> > > +#define kvm_riscv_exception_class                                         \
> > > +   EXC(INST_MISALIGNED), EXC(INST_ACCESS), EXC(INST_ILLEGAL),         \
> > > +   EXC(BREAKPOINT), EXC(LOAD_MISALIGNED), EXC(LOAD_ACCESS),           \
> > > +   EXC(STORE_MISALIGNED), EXC(STORE_ACCESS), EXC(SYSCALL),            \
> > > +   EXC(HYPERVISOR_SYSCALL), EXC(SUPERVISOR_SYSCALL),                  \
> > > +   EXC(INST_PAGE_FAULT), EXC(LOAD_PAGE_FAULT), EXC(STORE_PAGE_FAULT), \
> > > +   EXC(INST_GUEST_PAGE_FAULT), EXC(LOAD_GUEST_PAGE_FAULT),            \
> > > +   EXC(VIRTUAL_INST_FAULT), EXC(STORE_GUEST_PAGE_FAULT)
> > > +
> > > +#endif /* ARCH_PERF_RISCV_EXCEPTION_TYPES_H */
> > > --
> > > 2.37.2
> > >