[PATCH] MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration

[PATCH] MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration

[Leonid Yegoshin]

This patch removes a temporary hack for debugging SMTC configuration from

	commit 41c594ab65fc89573af296d192aa5235d09717ab
	Author: Ralf Baechle <ralf@linux-mips.org>
	Date:   Wed Apr 5 09:45:45 2006 +0100

which is dropped now. Some performance degradation for multi-VPE systems
is removed.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
---
 arch/mips/include/asm/r4kcache.h |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/arch/mips/include/asm/r4kcache.h b/arch/mips/include/asm/r4kcache.h
index 4520adc..b2ae1b1 100644
--- a/arch/mips/include/asm/r4kcache.h
+++ b/arch/mips/include/asm/r4kcache.h
@@ -50,7 +50,6 @@ extern void (*r4k_blast_icache)(void);
 /*
  * Optionally force single-threaded execution during I-cache flushes.
  */
-#define PROTECT_CACHE_FLUSHES 1
 
 #ifdef PROTECT_CACHE_FLUSHES
 

Re: [PATCH] MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration

[Ralf Baechle]

On Fri, Sep 05, 2014 at 07:27:38PM -0700, Leonid Yegoshin wrote:

> This patch removes a temporary hack for debugging SMTC configuration from
> 
> 	commit 41c594ab65fc89573af296d192aa5235d09717ab
> 	Author: Ralf Baechle <ralf@linux-mips.org>
> 	Date:   Wed Apr 5 09:45:45 2006 +0100
> 
> which is dropped now. Some performance degradation for multi-VPE systems
> is removed.

Your patch removes the sole location from where PROTECT_CACHE_FLUSHES
was defined leaving all the #ifdef'ed PROTECT_CACHE_FLUSHES code unused.
So I'm more thinking of something like below.

  Ralf

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

 arch/mips/include/asm/r4kcache.h | 59 ----------------------------------------
 1 file changed, 59 deletions(-)

diff --git a/arch/mips/include/asm/r4kcache.h b/arch/mips/include/asm/r4kcache.h
index cd6e0af..e293a8d 100644
--- a/arch/mips/include/asm/r4kcache.h
+++ b/arch/mips/include/asm/r4kcache.h
@@ -47,79 +47,20 @@ extern void (*r4k_blast_icache)(void);
 
 #ifdef CONFIG_MIPS_MT
 
-/*
- * Optionally force single-threaded execution during I-cache flushes.
- */
-#define PROTECT_CACHE_FLUSHES 1
-
-#ifdef PROTECT_CACHE_FLUSHES
-
-extern int mt_protiflush;
-extern int mt_protdflush;
-extern void mt_cflush_lockdown(void);
-extern void mt_cflush_release(void);
-
-#define BEGIN_MT_IPROT \
-	unsigned long flags = 0;			\
-	unsigned long mtflags = 0;			\
-	if(mt_protiflush) {				\
-		local_irq_save(flags);			\
-		ehb();					\
-		mtflags = dvpe();			\
-		mt_cflush_lockdown();			\
-	}
-
-#define END_MT_IPROT \
-	if(mt_protiflush) {				\
-		mt_cflush_release();			\
-		evpe(mtflags);				\
-		local_irq_restore(flags);		\
-	}
-
-#define BEGIN_MT_DPROT \
-	unsigned long flags = 0;			\
-	unsigned long mtflags = 0;			\
-	if(mt_protdflush) {				\
-		local_irq_save(flags);			\
-		ehb();					\
-		mtflags = dvpe();			\
-		mt_cflush_lockdown();			\
-	}
-
-#define END_MT_DPROT \
-	if(mt_protdflush) {				\
-		mt_cflush_release();			\
-		evpe(mtflags);				\
-		local_irq_restore(flags);		\
-	}
-
-#else
-
-#define BEGIN_MT_IPROT
-#define BEGIN_MT_DPROT
-#define END_MT_IPROT
-#define END_MT_DPROT
-
-#endif /* PROTECT_CACHE_FLUSHES */
-
 #define __iflush_prologue						\
 	unsigned long redundance;					\
 	extern int mt_n_iflushes;					\
-	BEGIN_MT_IPROT							\
 	for (redundance = 0; redundance < mt_n_iflushes; redundance++) {
 
 #define __iflush_epilogue						\
-	END_MT_IPROT							\
 	}
 
 #define __dflush_prologue						\
 	unsigned long redundance;					\
 	extern int mt_n_dflushes;					\
-	BEGIN_MT_DPROT							\
 	for (redundance = 0; redundance < mt_n_dflushes; redundance++) {
 
 #define __dflush_epilogue \
-	END_MT_DPROT	 \
 	}
 
 #define __inv_dflush_prologue __dflush_prologue

Re: [PATCH] MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration

[Ralf Baechle]

On Thu, Nov 20, 2014 at 10:45:58PM +0100, Ralf Baechle wrote:

> So I'm more thinking of something like below.

And while we're at it, these were unused rsp. only used by other
unused macros.

  Ralf

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

 arch/mips/include/asm/r4kcache.h | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/arch/mips/include/asm/r4kcache.h b/arch/mips/include/asm/r4kcache.h
index cd6e0af..392b159 100644
--- a/arch/mips/include/asm/r4kcache.h
+++ b/arch/mips/include/asm/r4kcache.h
@@ -124,10 +124,6 @@ extern void mt_cflush_release(void);
 
 #define __inv_dflush_prologue __dflush_prologue
 #define __inv_dflush_epilogue __dflush_epilogue
-#define __sflush_prologue {
-#define __sflush_epilogue }
-#define __inv_sflush_prologue __sflush_prologue
-#define __inv_sflush_epilogue __sflush_epilogue
 
 #else /* CONFIG_MIPS_MT */
 
@@ -137,10 +133,6 @@ extern void mt_cflush_release(void);
 #define __dflush_epilogue }
 #define __inv_dflush_prologue {
 #define __inv_dflush_epilogue }
-#define __sflush_prologue {
-#define __sflush_epilogue }
-#define __inv_sflush_prologue {
-#define __inv_sflush_epilogue }
 
 #endif /* CONFIG_MIPS_MT */