Re: [PATCH v2 2/3] hw/mips/gt64xxx: Remove dynamic field width from trace events

[Eric Blake <eblake@redhat.com>]

On 11/8/19 8:40 AM, Philippe Mathieu-Daudé wrote:
> Since not all trace backends support dynamic field width in
> format (dtrace via stap does not), replace by a static field
> width instead.
> 
> Reported-by: Eric Blake <eblake@redhat.com>
> Buglink: https://bugs.launchpad.net/qemu/+bug/1844817
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> v2: Do not update qemu_log_mask()
> ---
>   hw/mips/gt64xxx_pci.c | 16 ++++++++--------
>   hw/mips/trace-events  |  4 ++--
>   2 files changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/hw/mips/gt64xxx_pci.c b/hw/mips/gt64xxx_pci.c
> index 5cab9c1ee1..6743e7c929 100644
> --- a/hw/mips/gt64xxx_pci.c
> +++ b/hw/mips/gt64xxx_pci.c
> @@ -642,19 +642,19 @@ static void gt64120_writel(void *opaque, hwaddr addr,
>           /* not really implemented */
>           s->regs[saddr] = ~(~(s->regs[saddr]) | ~(val & 0xfffffffe));
>           s->regs[saddr] |= !!(s->regs[saddr] & 0xfffffffe);
> -        trace_gt64120_write("INTRCAUSE", size << 1, val);
> +        trace_gt64120_write("INTRCAUSE", size << 3, val);

Again, this isn't mentioned in the commit message.  Why are you changing 
parameter values?


> +++ b/hw/mips/trace-events
> @@ -1,4 +1,4 @@
>   # gt64xxx.c
> -gt64120_read(const char *regname, int width, uint64_t value) "gt64120 read %s value:0x%0*" PRIx64
> -gt64120_write(const char *regname, int width, uint64_t value) "gt64120 write %s value:0x%0*" PRIx64
> +gt64120_read(const char *regname, int width, uint64_t value) "gt64120 read %s width:%d value:0x%08" PRIx64
> +gt64120_write(const char *regname, int width, uint64_t value) "gt64120 write %s width:%d value:0x%08" PRIx64

Huh, we were really broken - the old code (if passed to printf) would 
try to parse 4 parameters, even though it was only passed 3.  But it 
looks like you still need a v3.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org