[PATCH] Make __declare_dbe_table() static

[PATCH] Make __declare_dbe_table() static

[Atsushi Nemoto]

Make __declare_dbe_table() static and call it explicitly to ensure not
optimized out.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
---
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index cfd1785..78a3f75 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -340,7 +340,7 @@ NORET_TYPE void ATTRIB_NORET die(const c
 extern const struct exception_table_entry __start___dbe_table[];
 extern const struct exception_table_entry __stop___dbe_table[];
 
-void __declare_dbe_table(void)
+static void __declare_dbe_table(void)
 {
 	__asm__ __volatile__(
 	".section\t__dbe_table,\"a\"\n\t"
@@ -1576,4 +1576,5 @@ void __init trap_init(void)
 
 	flush_icache_range(ebase, ebase + 0x400);
 	flush_tlb_handlers();
+	__declare_dbe_table();
 }

Re: [PATCH] Make __declare_dbe_table() static

[Ralf Baechle]

On Mon, Feb 19, 2007 at 12:44:35AM +0900, Atsushi Nemoto wrote:

> Make __declare_dbe_table() static and call it explicitly to ensure not
> optimized out.

That's what __attribute_used__ was meant to be used for.

  Ralf

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index cfd1785..db0a9a2 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -340,7 +340,7 @@ NORET_TYPE void ATTRIB_NORET die(const char * str, struct pt_regs * regs)
 extern const struct exception_table_entry __start___dbe_table[];
 extern const struct exception_table_entry __stop___dbe_table[];
 
-void __declare_dbe_table(void)
+static void __attribute_used__ __declare_dbe_table(void)
 {
 	__asm__ __volatile__(
 	".section\t__dbe_table,\"a\"\n\t"

Re: [PATCH] Make __declare_dbe_table() static

[Atsushi Nemoto]

On Sun, 18 Feb 2007 15:54:08 +0000, Ralf Baechle <ralf@linux-mips.org> wrote:
> > Make __declare_dbe_table() static and call it explicitly to ensure not
> > optimized out.
> 
> That's what __attribute_used__ was meant to be used for.

But we do not need empty __declare_dbe_table() function body (jr ra +
nop) at all.  If we called it explicitly, compiler will optimized it
out.  Saves two instructions ;)

Re: [PATCH] Make __declare_dbe_table() static

[Ralf Baechle]

On Mon, Feb 19, 2007 at 12:58:50AM +0900, Atsushi Nemoto wrote:

> On Sun, 18 Feb 2007 15:54:08 +0000, Ralf Baechle <ralf@linux-mips.org> wrote:
> > > Make __declare_dbe_table() static and call it explicitly to ensure not
> > > optimized out.
> > 
> > That's what __attribute_used__ was meant to be used for.
> 
> But we do not need empty __declare_dbe_table() function body (jr ra +
> nop) at all.  If we called it explicitly, compiler will optimized it
> out.  Saves two instructions ;)

_asm__(
"       .section        __dbe_table, \"a\"\n"
"       .previous                       \n");

is even simpler :-)

  Ralf

Re: [PATCH] Make __declare_dbe_table() static

[Atsushi Nemoto]

On Sun, 18 Feb 2007 16:13:52 +0000, Ralf Baechle <ralf@linux-mips.org> wrote:
> _asm__(
> "       .section        __dbe_table, \"a\"\n"
> "       .previous                       \n");
> 
> is even simpler :-)

Oh yes.  Right fix it should be.
---
Atsushi Nemoto