Re: [Qemu-devel] [PATCH v3 04/52] acpi: factor out ACPI const int packing out of build_append_value()

[Igor Mammedov <imammedo@redhat.com>]

On Tue, 17 Feb 2015 20:53:52 +0100
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> On Mon, Feb 09, 2015 at 10:53:26AM +0000, Igor Mammedov wrote:
> > it will be reused for adding a plain integer value into AML.
> > 
> > Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> > ---
> >  hw/acpi/aml-build.c  | 19 +++----------------
> >  hw/i386/acpi-build.c |  6 +++---
> >  2 files changed, 6 insertions(+), 19 deletions(-)
> > 
> > diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
> > index 096f347..67d1371 100644
> > --- a/hw/acpi/aml-build.c
> > +++ b/hw/acpi/aml-build.c
> > @@ -221,24 +221,8 @@ void build_extop_package(GArray *package, uint8_t op)
> >  
> >  void build_append_value(GArray *table, uint32_t value, int size)
> >  {
> > -    uint8_t prefix;
> >      int i;
> >  
> > -    switch (size) {
> > -    case 1:
> > -        prefix = 0x0A; /* BytePrefix */
> > -        break;
> > -    case 2:
> > -        prefix = 0x0B; /* WordPrefix */
> > -        break;
> > -    case 4:
> > -        prefix = 0x0C; /* DWordPrefix */
> > -        break;
> > -    default:
> > -        assert(0);
> > -        return;
> > -    }
> > -    build_append_byte(table, prefix);
> >      for (i = 0; i < size; ++i) {
> >          build_append_byte(table, value & 0xFF);
> >          value = value >> 8;
> 
> This really makes this an awkward API,
> you must remember to add the prefix.
it's internal helper for adding plain values,
it's not intended for using outside aml-build.c
I should have marked it as static.

[...]
> then call build_append_value_noprefix from build_append_value.
lets rename it to build_append_int_noprefix as int is less vague then value
and leave prefixed part as it's /i.e. build_append_int()/


> 
> But really, it's best to squash such changes with
> where they are used, it's just making review harder:
> as you add APIs with no documentation, I can't
> see what they do without reading follow up patch
> to see how they are used.
It's split out to make the rest of patches more review-able
if I drop aml_def_block() patch then this patch might be squashed with:
"acpi: extend build_append_{value|int}() to support 64-bit values"
"acpi: add aml_int() term"
and that might be squashed into already huge patch
"pc: acpi-build: drop template patching and create PCI bus tree dynamically"

Squashing 3 different changes into a bigger patch doesn't make review any
easier and squashing that into 4th conversion patch makes it even worse.

> 
> 
> > @@ -252,10 +236,13 @@ void build_append_int(GArray *table, uint32_t value)
> >      } else if (value == 0x01) {
> >          build_append_byte(table, 0x01); /* OneOp */
> >      } else if (value <= 0xFF) {
> > +        build_append_byte(table, 0x0A); /* BytePrefix */
> >          build_append_value(table, value, 1);
> >      } else if (value <= 0xFFFF) {
> > +        build_append_byte(table, 0x0B); /* WordPrefix */
> >          build_append_value(table, value, 2);
> >      } else {
> > +        build_append_byte(table, 0x0C); /* DWordPrefix */
> >          build_append_value(table, value, 4);
> >      }
> >  }
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index 788962e..a1bf450 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -302,14 +302,14 @@ static void build_append_and_cleanup_method(GArray *device, GArray *method)
> >  
> >  static void build_append_notify_target_ifequal(GArray *method,
> >                                                 GArray *target_name,
> > -                                               uint32_t value, int size)
> > +                                               uint32_t value)
> >  {
> >      GArray *notify = build_alloc_array();
> >      uint8_t op = 0xA0; /* IfOp */
> >  
> >      build_append_byte(notify, 0x93); /* LEqualOp */
> >      build_append_byte(notify, 0x68); /* Arg0Op */
> > -    build_append_value(notify, value, size);
> > +    build_append_int(notify, value);
> >      build_append_byte(notify, 0x86); /* NotifyOp */
> >      build_append_array(notify, target_name);
> >      build_append_byte(notify, 0x69); /* Arg1Op */
> > @@ -578,7 +578,7 @@ build_append_notify_method(GArray *device, const char *name,
> >          GArray *target = build_alloc_array();
> >          build_append_namestring(target, format, i);
> >          assert(i < 256); /* Fits in 1 byte */
> > -        build_append_notify_target_ifequal(method, target, i, 1);
> > +        build_append_notify_target_ifequal(method, target, i);
> >          build_free_array(target);
> >      }
> >  
> > -- 
> > 1.8.3.1