vme: bridges: reduce stack usage

[ Upstream commit 7483e7a ]

With CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3, the stack usage in vme_fake
grows above the warning limit:

drivers/vme/bridges/vme_fake.c: In function 'fake_master_read':
drivers/vme/bridges/vme_fake.c:610:1: error: the frame size of 1160 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
drivers/vme/bridges/vme_fake.c: In function 'fake_master_write':
drivers/vme/bridges/vme_fake.c:797:1: error: the frame size of 1160 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

The problem is that in some configurations, each call to
fake_vmereadX() puts another variable on the stack.

Reduce the amount of inlining to get back to the previous state,
with no function using more than 200 bytes each.

Signed-off-by: Arnd Bergmann <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: arndb

drivers/vme/bridges/vme_fake.c

@@ -418,8 +418,9 @@ static void fake_lm_check(struct fake_driver *bridge, unsigned long long addr,
 	}
 }
 
-static u8 fake_vmeread8(struct fake_driver *bridge, unsigned long long addr,
-		u32 aspace, u32 cycle)
+static noinline_for_stack u8 fake_vmeread8(struct fake_driver *bridge,
+					   unsigned long long addr,
+					   u32 aspace, u32 cycle)
 {
 	u8 retval = 0xff;
 	int i;
@@ -450,8 +451,9 @@ static u8 fake_vmeread8(struct fake_driver *bridge, unsigned long long addr,
 	return retval;
 }
 
-static u16 fake_vmeread16(struct fake_driver *bridge, unsigned long long addr,
-		u32 aspace, u32 cycle)
+static noinline_for_stack u16 fake_vmeread16(struct fake_driver *bridge,
+					     unsigned long long addr,
+					     u32 aspace, u32 cycle)
 {
 	u16 retval = 0xffff;
 	int i;
@@ -482,8 +484,9 @@ static u16 fake_vmeread16(struct fake_driver *bridge, unsigned long long addr,
 	return retval;
 }
 
-static u32 fake_vmeread32(struct fake_driver *bridge, unsigned long long addr,
-		u32 aspace, u32 cycle)
+static noinline_for_stack u32 fake_vmeread32(struct fake_driver *bridge,
+					     unsigned long long addr,
+					     u32 aspace, u32 cycle)
 {
 	u32 retval = 0xffffffff;
 	int i;
@@ -613,8 +616,9 @@ static ssize_t fake_master_read(struct vme_master_resource *image, void *buf,
 	return retval;
 }
 
-static void fake_vmewrite8(struct fake_driver *bridge, u8 *buf,
-			   unsigned long long addr, u32 aspace, u32 cycle)
+static noinline_for_stack void fake_vmewrite8(struct fake_driver *bridge,
+					      u8 *buf, unsigned long long addr,
+					      u32 aspace, u32 cycle)
 {
 	int i;
 	unsigned long long start, end, offset;
@@ -643,8 +647,9 @@ static void fake_vmewrite8(struct fake_driver *bridge, u8 *buf,
 
 }
 
-static void fake_vmewrite16(struct fake_driver *bridge, u16 *buf,
-			    unsigned long long addr, u32 aspace, u32 cycle)
+static noinline_for_stack void fake_vmewrite16(struct fake_driver *bridge,
+					       u16 *buf, unsigned long long addr,
+					       u32 aspace, u32 cycle)
 {
 	int i;
 	unsigned long long start, end, offset;
@@ -673,8 +678,9 @@ static void fake_vmewrite16(struct fake_driver *bridge, u16 *buf,
 
 }
 
-static void fake_vmewrite32(struct fake_driver *bridge, u32 *buf,
-			    unsigned long long addr, u32 aspace, u32 cycle)
+static noinline_for_stack void fake_vmewrite32(struct fake_driver *bridge,
+					       u32 *buf, unsigned long long addr,
+					       u32 aspace, u32 cycle)
 {
 	int i;
 	unsigned long long start, end, offset;