On Tue, Dec 17, 2019 at 01:06:00PM +1100, Gavin Shan wrote:
> The filter name is fixed to "exit_reason" for some kvm_exit events, no
> matter what architect we have. Actually, the filter name ("exit_reason")
> is only applicable to x86, meaning it's broken on other architects
> including aarch64.
>
> This fixes the issue by providing various kvm_exit filter names, depending
> on architect we're on. Afterwards, the variable filter name is picked and
> applied by ioctl(fd, SET_FILTER).
>
> Reported-by: Andrew Jones <drjones@xxxxxxxxxx>
This wasn't reported by me - I was just the middleman. Credit should go
to Jeff Bastian <jbastian@xxxxxxxxxx>
> Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx>
> ---
> v2: Rename exit_field to exit_reason_field
> Fix the name to esr_ec for aarch64
> ---
> tools/kvm/kvm_stat/kvm_stat | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/tools/kvm/kvm_stat/kvm_stat b/tools/kvm/kvm_stat/kvm_stat
> index ad1b9e646c49..4cf93110c259 100755
> --- a/tools/kvm/kvm_stat/kvm_stat
> +++ b/tools/kvm/kvm_stat/kvm_stat
> @@ -270,6 +270,7 @@ class ArchX86(Arch):
> def __init__(self, exit_reasons):
> self.sc_perf_evt_open = 298
> self.ioctl_numbers = IOCTL_NUMBERS
> + self.exit_reason_field = 'exit_reason'
> self.exit_reasons = exit_reasons
>
> def debugfs_is_child(self, field):
> @@ -289,6 +290,7 @@ class ArchPPC(Arch):
> # numbers depend on the wordsize.
> char_ptr_size = ctypes.sizeof(ctypes.c_char_p)
> self.ioctl_numbers['SET_FILTER'] = 0x80002406 | char_ptr_size << 16
> + self.exit_reason_field = 'exit_nr'
> self.exit_reasons = {}
>
> def debugfs_is_child(self, field):
> @@ -300,6 +302,7 @@ class ArchA64(Arch):
> def __init__(self):
> self.sc_perf_evt_open = 241
> self.ioctl_numbers = IOCTL_NUMBERS
> + self.exit_reason_field = 'esr_ec'
> self.exit_reasons = AARCH64_EXIT_REASONS
>
> def debugfs_is_child(self, field):
> @@ -311,6 +314,7 @@ class ArchS390(Arch):
> def __init__(self):
> self.sc_perf_evt_open = 331
> self.ioctl_numbers = IOCTL_NUMBERS
> + self.exit_reason_field = None
> self.exit_reasons = None
>
> def debugfs_is_child(self, field):
> @@ -541,8 +545,8 @@ class TracepointProvider(Provider):
> """
> filters = {}
> filters['kvm_userspace_exit'] = ('reason', USERSPACE_EXIT_REASONS)
> - if ARCH.exit_reasons:
> - filters['kvm_exit'] = ('exit_reason', ARCH.exit_reasons)
> + if ARCH.exit_reason_field and ARCH.exit_reasons:
> + filters['kvm_exit'] = (ARCH.exit_reason_field, ARCH.exit_reasons)
> return filters
>
> def _get_available_fields(self):
> --
> 2.23.0
>
Looks like a reasonable fix to me.
Reviewed-by: Andrew Jones <drjones@xxxxxxxxxx>
