[PATCH v3 2/9] x86: move common_interrupt to entry.S

[PATCH v3 2/9] x86: move common_interrupt to entry.S

[Feng Wu]

This patch moves label common_interrupt from asm_defns.h to entry.S

Signed-off-by: Feng Wu <feng.wu@intel.com>
---
 xen/arch/x86/i8259.c                   | 4 ----
 xen/arch/x86/x86_64/entry.S            | 6 ++++++
 xen/include/asm-x86/x86_64/asm_defns.h | 9 ---------
 3 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/xen/arch/x86/i8259.c b/xen/arch/x86/i8259.c
index 6fdcce8..cd4d097 100644
--- a/xen/arch/x86/i8259.c
+++ b/xen/arch/x86/i8259.c
@@ -33,10 +33,6 @@
  * interrupt-controller happy.
  */
 
-__asm__(".section .text");
-
-BUILD_COMMON_IRQ()
-
 #define IRQ_NAME(nr) VEC##nr##_interrupt
 
 #define BI(nr)                                           \
diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S
index 3ea4683..1c81852 100644
--- a/xen/arch/x86/x86_64/entry.S
+++ b/xen/arch/x86/x86_64/entry.S
@@ -465,6 +465,12 @@ ENTRY(dom_crash_sync_extable)
         xorl  %edi,%edi
         jmp   asm_domain_crash_synchronous /* Does not return */
 
+ENTRY(common_interrupt)
+        SAVE_ALL
+        movq %rsp,%rdi
+        callq do_IRQ
+        jmp ret_from_intr
+
 /* No special register assumptions. */
 ENTRY(ret_from_intr)
         GET_CURRENT(%rbx)
diff --git a/xen/include/asm-x86/x86_64/asm_defns.h b/xen/include/asm-x86/x86_64/asm_defns.h
index bf63ac1..cb5669d 100644
--- a/xen/include/asm-x86/x86_64/asm_defns.h
+++ b/xen/include/asm-x86/x86_64/asm_defns.h
@@ -208,15 +208,6 @@
 #define REX64_PREFIX "rex64/"
 #endif
 
-#define BUILD_COMMON_IRQ()                      \
-__asm__(                                        \
-    "\n" __ALIGN_STR"\n"                        \
-    "common_interrupt:\n\t"                     \
-    STR(SAVE_ALL) "\n\t"                        \
-    "movq %rsp,%rdi\n\t"                        \
-    "callq " STR(do_IRQ) "\n\t"                 \
-    "jmp ret_from_intr\n");
-
 #define BUILD_IRQ(nr)                           \
     "pushq $0\n\t"                              \
     "movl $"#nr",4(%rsp)\n\t"                   \
-- 
1.8.3.1

Re: [PATCH v3 2/9] x86: move common_interrupt to entry.S

[Jan Beulich]

>>> On 28.04.14 at 05:14, <feng.wu@intel.com> wrote:
> --- a/xen/arch/x86/i8259.c
> +++ b/xen/arch/x86/i8259.c
> @@ -33,10 +33,6 @@
>   * interrupt-controller happy.
>   */
>  
> -__asm__(".section .text");

I don't think you can remove this without having removed ...

> -
> -BUILD_COMMON_IRQ()
> -
>  #define IRQ_NAME(nr) VEC##nr##_interrupt
>  
>  #define BI(nr)                                           \

... everything from here downwards relating to the entry point
construction.

With that fixed,
Reviewed-by: Jan Beulich <jbeulich@suse.com>

Re: [PATCH v3 2/9] x86: move common_interrupt to entry.S

[Wu, Feng]

> -----Original Message-----
> From: Jan Beulich [mailto:JBeulich@suse.com]
> Sent: Monday, April 28, 2014 5:16 PM
> To: Wu, Feng
> Cc: andrew.cooper3@citrix.com; ian.campbell@citrix.com; Dong, Eddie;
> Nakajima, Jun; Tian, Kevin; xen-devel@lists.xen.org
> Subject: Re: [PATCH v3 2/9] x86: move common_interrupt to entry.S
> 
> >>> On 28.04.14 at 05:14, <feng.wu@intel.com> wrote:
> > --- a/xen/arch/x86/i8259.c
> > +++ b/xen/arch/x86/i8259.c
> > @@ -33,10 +33,6 @@
> >   * interrupt-controller happy.
> >   */
> >
> > -__asm__(".section .text");
> 
> I don't think you can remove this without having removed ...
> 
> > -
> > -BUILD_COMMON_IRQ()
> > -
> >  #define IRQ_NAME(nr) VEC##nr##_interrupt
> >
> >  #define BI(nr)                                           \
> 
> ... everything from here downwards relating to the entry point
> construction.

I will add "__asm__(".section .text");" back.

> 
> With that fixed,
> Reviewed-by: Jan Beulich <jbeulich@suse.com>

Thanks,
Feng

Re: [PATCH v3 2/9] x86: move common_interrupt to entry.S

[Andrew Cooper]

On 28/04/14 04:14, Feng Wu wrote:
> This patch moves label common_interrupt from asm_defns.h to entry.S
>
> Signed-off-by: Feng Wu <feng.wu@intel.com>

I am fairly sure the __asm__(".section .text"); was bogus, given no
obvious special case hacks play with the sections of this file.

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

> ---
>  xen/arch/x86/i8259.c                   | 4 ----
>  xen/arch/x86/x86_64/entry.S            | 6 ++++++
>  xen/include/asm-x86/x86_64/asm_defns.h | 9 ---------
>  3 files changed, 6 insertions(+), 13 deletions(-)
>
> diff --git a/xen/arch/x86/i8259.c b/xen/arch/x86/i8259.c
> index 6fdcce8..cd4d097 100644
> --- a/xen/arch/x86/i8259.c
> +++ b/xen/arch/x86/i8259.c
> @@ -33,10 +33,6 @@
>   * interrupt-controller happy.
>   */
>  
> -__asm__(".section .text");
> -
> -BUILD_COMMON_IRQ()
> -
>  #define IRQ_NAME(nr) VEC##nr##_interrupt
>  
>  #define BI(nr)                                           \
> diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S
> index 3ea4683..1c81852 100644
> --- a/xen/arch/x86/x86_64/entry.S
> +++ b/xen/arch/x86/x86_64/entry.S
> @@ -465,6 +465,12 @@ ENTRY(dom_crash_sync_extable)
>          xorl  %edi,%edi
>          jmp   asm_domain_crash_synchronous /* Does not return */
>  
> +ENTRY(common_interrupt)
> +        SAVE_ALL
> +        movq %rsp,%rdi
> +        callq do_IRQ
> +        jmp ret_from_intr
> +
>  /* No special register assumptions. */
>  ENTRY(ret_from_intr)
>          GET_CURRENT(%rbx)
> diff --git a/xen/include/asm-x86/x86_64/asm_defns.h b/xen/include/asm-x86/x86_64/asm_defns.h
> index bf63ac1..cb5669d 100644
> --- a/xen/include/asm-x86/x86_64/asm_defns.h
> +++ b/xen/include/asm-x86/x86_64/asm_defns.h
> @@ -208,15 +208,6 @@
>  #define REX64_PREFIX "rex64/"
>  #endif
>  
> -#define BUILD_COMMON_IRQ()                      \
> -__asm__(                                        \
> -    "\n" __ALIGN_STR"\n"                        \
> -    "common_interrupt:\n\t"                     \
> -    STR(SAVE_ALL) "\n\t"                        \
> -    "movq %rsp,%rdi\n\t"                        \
> -    "callq " STR(do_IRQ) "\n\t"                 \
> -    "jmp ret_from_intr\n");
> -
>  #define BUILD_IRQ(nr)                           \
>      "pushq $0\n\t"                              \
>      "movl $"#nr",4(%rsp)\n\t"                   \

Re: [PATCH v3 2/9] x86: move common_interrupt to entry.S

[Jan Beulich]

>>> On 28.04.14 at 11:25, <andrew.cooper3@citrix.com> wrote:
> On 28/04/14 04:14, Feng Wu wrote:
>> This patch moves label common_interrupt from asm_defns.h to entry.S
>>
>> Signed-off-by: Feng Wu <feng.wu@intel.com>
> 
> I am fairly sure the __asm__(".section .text"); was bogus, given no
> obvious special case hacks play with the sections of this file.

I'm fairly sure it's needed, and - what may make things worse - only
with some compiler versions: If the compiler emitted any data before
processing the file scope asm()s, the code generated here would end
up in that data section.

Jan

Re: [PATCH v3 2/9] x86: move common_interrupt to entry.S

[Andrew Cooper]

On 28/04/14 10:48, Jan Beulich wrote:
>>>> On 28.04.14 at 11:25, <andrew.cooper3@citrix.com> wrote:
>> On 28/04/14 04:14, Feng Wu wrote:
>>> This patch moves label common_interrupt from asm_defns.h to entry.S
>>>
>>> Signed-off-by: Feng Wu <feng.wu@intel.com>
>> I am fairly sure the __asm__(".section .text"); was bogus, given no
>> obvious special case hacks play with the sections of this file.
> I'm fairly sure it's needed, and - what may make things worse - only
> with some compiler versions: If the compiler emitted any data before
> processing the file scope asm()s, the code generated here would end
> up in that data section.
>
> Jan

Ah ok.  In which case it needs to be kept until all the interrupt logic
has moved.

~Andrew