redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

MIPS: math-emu: Reuse name array in debugfs_fpuemu() 

The FPU_STAT_CREATE_EX() macro used 114 times in debugfs_fpuemu()
declares a 32 byte char array to hold the name of a debugfs file. Since
each use of the macro declares a new char array out of the scope of all
the other uses, we end up with an unnecessarily large stack frame of
3648 bytes (ie. 114*32) plus the size of 2 pointers
(fpuemu_debugfs_base_dir & fpuemu_debugfs_inst_dir). This is enough to
trigger the frame size warnings from GCC in common configurations.

Avoid the unnecessary stack bloat by using a single name char array
which each usage of FPU_STAT_CREATE_EX() will reinitialize via the
strcpy() in adjust_instruction_counter_name().

Signed-off-by: Paul Burton <paulburton@kernel.org>
Reported-by: kbuild test robot <lkp@intel.com>
URL: https://lore.kernel.org/linux-mips/201911090929.xvXYuHUz%25lkp@intel.com/
alistair/sunxi64-5.5-dsi
Paul Burton 2019-11-11 10:50:59 -08:00
parent dcf78ee660
commit 7d73d57211
No known key found for this signature in database
GPG Key ID: 3EA79FACB57500DD
1 changed files with 1 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/mips/math-emu/me-debugfs.c
View File

@ -189,6 +189,7 @@ static int __init debugfs_fpuemu(void)
{
struct dentry *fpuemu_debugfs_base_dir;
struct dentry *fpuemu_debugfs_inst_dir;
char name[32];
fpuemu_debugfs_base_dir = debugfs_create_dir("fpuemustats",
mips_debugfs_dir);
@ -225,8 +226,6 @@ do { \
#define FPU_STAT_CREATE_EX(m) \
do { \
char name[32]; \
\
adjust_instruction_counter_name(name, #m); \
\
debugfs_create_file(name, 0444, fpuemu_debugfs_inst_dir, \