[Cbe-oss-dev] [PATCH 02/28]MARS/base: prevent use of non volatile regs

[Yuji Mano]

From: Kazunori Asayama <asayama at sm.sony.co.jp>

Guarantee non-volatile regs are not broken during scheduling workload

This patch guarantees non-volatile registers are not broken during
workload scheduling is performed by using -mfixed-range compiler
option. This patch also removes unnecessary 'noinline' attributes in
the kernel implementation.

Signed-off-by: Kazunori Asayama <asayama at sm.sony.co.jp>
---
 base/src/mpu/kernel/Makefile.am |    1 +
 base/src/mpu/kernel/kernel.c    |   36 +++++++++++++++++++++---------------
 2 files changed, 22 insertions(+), 15 deletions(-)

Index: b/base/src/mpu/kernel/Makefile.am
===================================================================
--- a/base/src/mpu/kernel/Makefile.am	2009-01-22 13:52:59.000000000 +0900
+++ b/base/src/mpu/kernel/Makefile.am	2009-01-22 22:42:58.000000000 +0900
@@ -72,6 +72,7 @@ AM_CCASFLAGS = \
 
 AM_CFLAGS = \
 	$(extra_cflags) \
+	-mfixed-range=80-127 \
 	-W \
 	-Wall \
 	-Wunused \
Index: b/base/src/mpu/kernel/kernel.c
===================================================================
--- a/base/src/mpu/kernel/kernel.c	2009-01-22 13:52:59.000000000 +0900
+++ b/base/src/mpu/kernel/kernel.c	2009-01-22 22:48:04.000000000 +0900
@@ -575,7 +575,7 @@ static void release_block(int block, int
 		notify_host_bits(block_ea, index);
 }
 
-static int __attribute__((noinline)) reserve_workload(void)
+static int reserve_workload(void)
 {
 	int block;
 	int index = -1;
@@ -601,7 +601,7 @@ static int __attribute__((noinline)) res
 	return MARS_WORKLOAD_RESERVED;
 }
 
-static void __attribute__((noinline)) release_workload(void)
+static void release_workload(void)
 {
 	int block = workload_id / MARS_WORKLOAD_PER_BLOCK;
 	int index = workload_id % MARS_WORKLOAD_PER_BLOCK;
@@ -613,7 +613,23 @@ static void __attribute__((noinline)) re
 	release_block(block, index);
 }
 
-static int __attribute__((noinline)) scheduler(void)
+static void __attribute__((noinline)) run_workload(void)
+{
+	/* save kernel stack pointer */
+	asm volatile (
+		"stqa	$sp, _kernel_stack;"
+	);
+
+	/* call module entry function */
+	((module_entry)workload.module.entry)(&kernel_syscalls);
+
+	/* label so module can jump back here at exit */
+	asm volatile (
+		"_module_exit:"
+	);
+}
+
+static int scheduler(void)
 {
 	int status;
 
@@ -642,21 +658,11 @@ static int __attribute__((noinline)) sch
 	memset((void *)MARS_WORKLOAD_MODULE_BASE_ADDR +
 	       workload.module.exec_size, 0, workload.module.bss_size);
 
-	/* save kernel stack pointer */
-	asm volatile (
-		"stqa	$sp, _kernel_stack;"
-	);
-
 	/* sync before executing loaded code */
 	spu_sync();
 
-	/* call module entry function */
-	((module_entry)workload.module.entry)(&kernel_syscalls);
-
-	/* label so module can jump back here at exit */
-	asm volatile (
-		"_module_exit:"
-	);
+	/* run workload */
+	run_workload();
 
 	/* release reservation of current workload */
 	release_workload();