On 11/11/2020 16:56, Stefan Hajnoczi wrote:
> SystemTap's dtrace(1) prints the following warning when it encounters
> long long arguments:
>
> Warning: /usr/bin/dtrace:trace/trace-dtrace-hw_virtio.dtrace:76: syntax
> error near:
> probe vhost_vdpa_dev_start
>
> Warning: Proceeding as if --no-pyparsing was given.
>
> Use the uint64_t and int64_t types, respectively. This works with all
> host CPU 32- and 64-bit data models (ILP32, LP64, and LLP64) that QEMU
> supports.
>
> Reported-by: Markus Armbruster <arm...@redhat.com>
> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
> Reviewed-by: Daniel P. Berrangé <berra...@redhat.com>
> Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>
> Message-id: 20201020094043.159935-1-stefa...@redhat.com
> Suggested-by: Daniel P. Berrangé <berra...@redhat.com>
> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
> ---
> scripts/tracetool/format/d.py | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/scripts/tracetool/format/d.py b/scripts/tracetool/format/d.py
> index 353722f89c..ebfb714200 100644
> --- a/scripts/tracetool/format/d.py
> +++ b/scripts/tracetool/format/d.py
> @@ -57,6 +57,12 @@ def generate(events, backend, group):
> # Avoid it by changing probe type to signed char *
> beforehand.
> if type_ == 'int8_t *':
> type_ = 'signed char *'
> +
> + # SystemTap dtrace(1) emits a warning when long long is used
> + type_ = type_.replace('unsigned long long', 'uint64_t')
> + type_ = type_.replace('signed long long', 'int64_t')
> + type_ = type_.replace('long long', 'int64_t')
> +
> if name in RESERVED_WORDS:
> name += '_'
> args.append(type_ + ' ' + name)
>
This patch fixes the warning with "d" format, but we have the same kind of
problem with
log-stap format:
$ sudo stap -e 'probe begin{printf ("BEGIN")}' -I .
parse error: invalid or missing conversion specifier
saw: operator ',' at ./qemu-system-x86_64-log.stp:15118:101
source: printf("%d@%d vhost_vdpa_set_log_base dev: %p base: 0x%x
size: %llu
refcnt: %d fd: %d log: %p\n", pid(), gettimeofday_ns(), dev, base, size,
refcnt, fd, log)
^
1 parse error.
WARNING: tapset "./qemu-system-x86_64-log.stp" has errors, and will be skipped
BEGIN
This happens because of the "%llu" in the format string.
I'm wondering if we need to fix all the stap based format or simply replace the
"unsigned
long long" by "uint64_t" in hw/virtio/trace-events?
Thanks,
Laurent
