On 01/26/2016 02:46 PM, Paolo Bonzini wrote:
> From: Janosch Frank <fran...@linux.vnet.ibm.com>
>
> Access checking with F_OK was replaced with the better readable
> os.path.exists().
>
> On Linux exists() returns False when the user doesn't have sufficient
> permissions for statting the directory. Therefore the error message
> now states that sufficient rights are needed when the check fails.
>
> Also added check for /sys/kernel/debug/tracing/.
>
> Signed-off-by: Janosch Frank <fran...@linux.vnet.ibm.com>
> Message-Id: <1452525484-32309-9-git-send-email-fran...@linux.vnet.ibm.com>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> scripts/kvm/kvm_stat | 16 +++++++++++-----
> 1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/scripts/kvm/kvm_stat b/scripts/kvm/kvm_stat
> index 5ca09f4..6f0692d 100755
> --- a/scripts/kvm/kvm_stat
> +++ b/scripts/kvm/kvm_stat
> @@ -473,12 +473,18 @@ class Stats:
> self.values[key] = (newval, newdelta)
> return self.values
>
> -if not os.access('/sys/kernel/debug', os.F_OK):
> - print 'Please enable CONFIG_DEBUG_FS in your kernel'
> +if not os.path.exists('/sys/kernel/debug'):
> + sys.stderr.write('Please enable CONFIG_DEBUG_FS in your kernel.')
> sys.exit(1)
> -if not os.access(PATH_DEBUGFS_KVM, os.F_OK):
> - print "Please mount debugfs ('mount -t debugfs debugfs
> /sys/kernel/debug')"
> - print "and ensure the kvm modules are loaded"
> +if not os.path.exists(PATH_DEBUGFS_KVM):
> + sys.stderr.write("Please make sure, that debugfs is mounted and "
> + "readable by the current user:\n"
> + "('mount -t debugfs debugfs /sys/kernel/debug')\n"
> + "Also ensure, that the kvm modules are loaded.\n")
> + sys.exit(1)
> +if not os.path.exists(PATH_DEBUGFS_TRACING):
> + sys.stderr.write("Please make {0} readable by the current user.\n"
> + .format(PATH_DEBUGFS_TRACING))
> sys.exit(1)
Hmmm, this now bails out on kernels without CONFIG_TRACING. It could still fall
back to the normal kvm_stat values. What about just removing the last
sys.exit(1)
and make this a warning that stays for a second or so?
