Re: [Qemu-devel] [PATCH v2 01/29] include: Make headers more self-contained

["Alex Bennée" <alex.bennee@linaro.org>]

Markus Armbruster <armbru@redhat.com> writes:

> Alex Bennée <alex.bennee@linaro.org> writes:
>
>> Markus Armbruster <armbru@redhat.com> writes:
>>
>>> Back in 2016, we discussed[1] rules for headers, and these were
>>> generally liked:
>>>
>>> 1. Have a carefully curated header that's included everywhere first.  We
>>>    got that already thanks to Peter: osdep.h.
>>>
>>> 2. Headers should normally include everything they need beyond osdep.h.
>>>    If exceptions are needed for some reason, they must be documented in
>>>    the header.  If all that's needed from a header is typedefs, put
>>>    those into qemu/typedefs.h instead of including the header.
>>>
>>> 3. Cyclic inclusion is forbidden.
>>>
>>> This patch gets include/ closer to obeying 2.
>>>
>>> It's actually extracted from my "[RFC] Baby steps towards saner
>>> headers" series[2], which demonstrates a possible path towards
>>> checking 2 automatically.  It passes the RFC test there.
>>>
>>> [1] Message-ID: <87h9g8j57d.fsf@blackfin.pond.sub.org>
>>>     https://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg03345.html
>>> [2] Message-Id: <20190711122827.18970-1-armbru@redhat.com>
>>>     https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg02715.html
>>>
>>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>>> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
>>> ---
>> <snip>
>>>  include/exec/cputlb.h                 | 2 ++
>>>  include/exec/exec-all.h               | 1 +
>>>  include/exec/ioport.h                 | 2 ++
>>>  include/exec/memory-internal.h        | 2 ++
>>>  include/exec/ram_addr.h               | 1 +
>>>  include/exec/softmmu-semi.h           | 2 ++
>>>  include/exec/tb-hash.h                | 2 ++
>>>  include/exec/user/thunk.h             | 1 +
>>>  include/fpu/softfloat-macros.h        | 2 ++
>> <snip>
>>>
>>>  /*
>>>   * bdrv_write_threshold_set:
>>> diff --git a/include/disas/disas.h b/include/disas/disas.h
>>> index 15da511f49..ba47e9197c 100644
>>> --- a/include/disas/disas.h
>>> +++ b/include/disas/disas.h
>>> @@ -1,6 +1,7 @@
>>>  #ifndef QEMU_DISAS_H
>>>  #define QEMU_DISAS_H
>>>
>>> +#include "exec/hwaddr.h"
>>>
>>>  #ifdef NEED_CPU_H
>>>  #include "cpu.h"
>>> diff --git a/include/exec/cputlb.h b/include/exec/cputlb.h
>>> index 5373188be3..23abd71579 100644
>>> --- a/include/exec/cputlb.h
>>> +++ b/include/exec/cputlb.h
>>> @@ -19,6 +19,8 @@
>>>  #ifndef CPUTLB_H
>>>  #define CPUTLB_H
>>>
>>> +#include "exec/cpu-common.h"
>>> +
>>>  #if !defined(CONFIG_USER_ONLY)
>>>  /* cputlb.c */
>>>  void tlb_protect_code(ram_addr_t ram_addr);
>>> diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
>>> index 16034ee651..135aeaab0d 100644
>>> --- a/include/exec/exec-all.h
>>> +++ b/include/exec/exec-all.h
>>> @@ -20,6 +20,7 @@
>>>  #ifndef EXEC_ALL_H
>>>  #define EXEC_ALL_H
>>>
>>> +#include "cpu.h"
>>>  #include "exec/tb-context.h"
>>>  #include "sysemu/cpus.h"
>>>
>>> diff --git a/include/exec/ioport.h b/include/exec/ioport.h
>>> index a298b89ce1..97feb296d2 100644
>>> --- a/include/exec/ioport.h
>>> +++ b/include/exec/ioport.h
>>> @@ -24,6 +24,8 @@
>>>  #ifndef IOPORT_H
>>>  #define IOPORT_H
>>>
>>> +#include "exec/memory.h"
>>> +
>>>  #define MAX_IOPORTS     (64 * 1024)
>>>  #define IOPORTS_MASK    (MAX_IOPORTS - 1)
>>>
>>> diff --git a/include/exec/memory-internal.h b/include/exec/memory-internal.h
>>> index d1a9dd1ec8..ef4fb92371 100644
>>> --- a/include/exec/memory-internal.h
>>> +++ b/include/exec/memory-internal.h
>>> @@ -20,6 +20,8 @@
>>>  #ifndef MEMORY_INTERNAL_H
>>>  #define MEMORY_INTERNAL_H
>>>
>>> +#include "cpu.h"
>>> +
>>>  #ifndef CONFIG_USER_ONLY
>>>  static inline AddressSpaceDispatch *flatview_to_dispatch(FlatView *fv)
>>>  {
>>> diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
>>> index b7b2e60ff6..a327a80cfe 100644
>>> --- a/include/exec/ram_addr.h
>>> +++ b/include/exec/ram_addr.h
>>> @@ -20,6 +20,7 @@
>>>  #define RAM_ADDR_H
>>>
>>>  #ifndef CONFIG_USER_ONLY
>>> +#include "cpu.h"
>>>  #include "hw/xen/xen.h"
>>>  #include "sysemu/tcg.h"
>>>  #include "exec/ramlist.h"
>>> diff --git a/include/exec/softmmu-semi.h b/include/exec/softmmu-semi.h
>>> index 970837992e..fbcae88f4b 100644
>>> --- a/include/exec/softmmu-semi.h
>>> +++ b/include/exec/softmmu-semi.h
>>> @@ -10,6 +10,8 @@
>>>  #ifndef SOFTMMU_SEMI_H
>>>  #define SOFTMMU_SEMI_H
>>>
>>> +#include "cpu.h"
>>> +
>>>  static inline uint64_t softmmu_tget64(CPUArchState *env, target_ulong addr)
>>>  {
>>>      uint64_t val;
>>> diff --git a/include/exec/tb-hash.h b/include/exec/tb-hash.h
>>> index 4f3a37d927..805235d321 100644
>>> --- a/include/exec/tb-hash.h
>>> +++ b/include/exec/tb-hash.h
>>> @@ -20,6 +20,8 @@
>>>  #ifndef EXEC_TB_HASH_H
>>>  #define EXEC_TB_HASH_H
>>>
>>> +#include "exec/cpu-defs.h"
>>> +#include "exec/exec-all.h"
>>>  #include "qemu/xxhash.h"
>>>
>>>  #ifdef CONFIG_SOFTMMU
>>> diff --git a/include/exec/user/thunk.h b/include/exec/user/thunk.h
>>> index 8d3af5a3be..d05a8a4dab 100644
>>> --- a/include/exec/user/thunk.h
>>> +++ b/include/exec/user/thunk.h
>>> @@ -20,6 +20,7 @@
>>>  #define THUNK_H
>>>
>>>  #include "cpu.h"
>>> +#include "exec/user/abitypes.h"
>>>
>>>  /* types enums definitions */
>>
>> These all seem OK.
>>
>>>
>>> diff --git a/include/fpu/softfloat-macros.h b/include/fpu/softfloat-macros.h
>>> index c55aa6d174..be83a833ec 100644
>>> --- a/include/fpu/softfloat-macros.h
>>> +++ b/include/fpu/softfloat-macros.h
>>> @@ -82,6 +82,8 @@ this code that are retained.
>>>  #ifndef FPU_SOFTFLOAT_MACROS_H
>>>  #define FPU_SOFTFLOAT_MACROS_H
>>>
>>> +#include "fpu/softfloat.h"
>>> +
>>
>> What does softfloat-macros actually need from the core softfloat API?
>> These are lower level functions used by softfloat itself (and m68k for
>> it's own bit fiddling).
>
> I extracted this patch out of "[PATCH RFC v5 0/3] Baby steps towards
> saner headers".  PATCH 1/3 creates make target "check-source", which is
> what I used to find headers that aren't self-contained.  In this case:
>
>   CC      cris-softmmu/tests/headers-tgt/include/fpu/softfloat.o
> In file included from tests/headers-tgt/include/fpu/softfloat-macros.c:21:
> /work/armbru/qemu/include/fpu/softfloat-macros.h: In function ‘estimateDiv128To64’:
> /work/armbru/qemu/include/fpu/softfloat-macros.h:623:27: error: implicit declaration of function ‘LIT64’ [-Werror=implicit-function-declaration]
>   623 |     if ( b <= a0 ) return LIT64( 0xFFFFFFFFFFFFFFFF );

The LIT64 definition should be moved to softfloat-types.h which is
already included by softfloat.h unless we already have a QEMU expansion
we should be using. The softfloat-macros.h can include softfloat-types.h
as well and we should only include the full softfloat.h if they need it.

Do you want me to spin up a patch?

>       |                           ^~~~~
> /work/armbru/qemu/include/fpu/softfloat-macros.h:623:27: error: nested extern declaration of ‘LIT64’ [-Werror=nested-externs]
> /work/armbru/qemu/include/fpu/softfloat-macros.h: At top level:
> /work/armbru/qemu/include/fpu/softfloat-macros.h:761:15: error: unknown type name ‘flag’
>   761 | static inline flag eq128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t b1 )
>       |               ^~~~
> /work/armbru/qemu/include/fpu/softfloat-macros.h:774:15: error: unknown type name ‘flag’
>   774 | static inline flag le128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t b1 )
>       |               ^~~~
> /work/armbru/qemu/include/fpu/softfloat-macros.h:787:15: error: unknown type name ‘flag’
>   787 | static inline flag lt128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t b1 )
>       |               ^~~~
> /work/armbru/qemu/include/fpu/softfloat-macros.h:800:15: error: unknown type name ‘flag’
>   800 | static inline flag ne128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t b1 )
>       |               ^~~~
> cc1: all warnings being treated as errors
> make[1]: *** [/work/armbru/qemu/rules.mak:69: tests/headers-tgt/include/fpu/softfloat-macros.o] Error 1


--
Alex Bennée