lkml.org 
[lkml]   [2020]   [Jan]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] vme: bridges: reduce stack usage
Date
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.

Fixes: mmtom ("init/Kconfig: enable -O3 for all arches")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/vme/bridges/vme_fake.c | 30 ++++++++++++++++++------------
1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/drivers/vme/bridges/vme_fake.c b/drivers/vme/bridges/vme_fake.c
index 3208a4409e44..6a1bc284f297 100644
--- a/drivers/vme/bridges/vme_fake.c
+++ b/drivers/vme/bridges/vme_fake.c
@@ -414,8 +414,9 @@ 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;
@@ -446,8 +447,9 @@ 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;
@@ -478,8 +480,9 @@ 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;
@@ -609,8 +612,9 @@ 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;
@@ -639,8 +643,9 @@ 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;
@@ -669,8 +674,9 @@ 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;
--
2.20.0
\
 
 \ /
  Last update: 2020-01-07 21:06    [W:0.033 / U:5.652 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site