lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

x86-64: Use absolute displacements for per-cpu accesses.

Browse Source 
Accessing memory through %gs should not use rip-relative addressing.
Adding a P prefix for the argument tells gcc to not add (%rip) to
the memory references.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Brian Gerst
2009-01-19 00:38:59 +09:00
committed by Tejun Heo
parent c2558e0eba
commit 87b2640658
2 changed files with 14 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
arch/x86/include/asm/percpu.h
View File

@@ -39,10 +39,10 @@
#include <linux/stringify.h>
#ifdef CONFIG_SMP
#define __percpu_seg_str "%%"__stringify(__percpu_seg)":"
#define __percpu_arg(x) "%%"__stringify(__percpu_seg)":%P" #x
#define __my_cpu_offset percpu_read(this_cpu_off)
#else
#define __percpu_seg_str
#define __percpu_arg(x) "%" #x
#endif
/* For arch-specific code, we can use direct single-insn ops (they
@@ -58,22 +58,22 @@ do { \
} \
switch (sizeof(var)) { \
case 1: \
asm(op "b %1,"__percpu_seg_str"%0" \
asm(op "b %1,"__percpu_arg(0) \
: "+m" (var) \
: "ri" ((T__)val)); \
break; \
case 2: \
asm(op "w %1,"__percpu_seg_str"%0" \
asm(op "w %1,"__percpu_arg(0) \
: "+m" (var) \
: "ri" ((T__)val)); \
break; \
case 4: \
asm(op "l %1,"__percpu_seg_str"%0" \
asm(op "l %1,"__percpu_arg(0) \
: "+m" (var) \
: "ri" ((T__)val)); \
break; \
case 8: \
asm(op "q %1,"__percpu_seg_str"%0" \
asm(op "q %1,"__percpu_arg(0) \
: "+m" (var) \
: "r" ((T__)val)); \
break; \
@@ -86,22 +86,22 @@ do { \
typeof(var) ret__; \
switch (sizeof(var)) { \
case 1: \
asm(op "b "__percpu_seg_str"%1,%0" \
asm(op "b "__percpu_arg(1)",%0" \
: "=r" (ret__) \
: "m" (var)); \
break; \
case 2: \
asm(op "w "__percpu_seg_str"%1,%0" \
asm(op "w "__percpu_arg(1)",%0" \
: "=r" (ret__) \
: "m" (var)); \
break; \
case 4: \
asm(op "l "__percpu_seg_str"%1,%0" \
asm(op "l "__percpu_arg(1)",%0" \
: "=r" (ret__) \
: "m" (var)); \
break; \
case 8: \
asm(op "q "__percpu_seg_str"%1,%0" \
asm(op "q "__percpu_arg(1)",%0" \
: "=r" (ret__) \
: "m" (var)); \
break; \
@@ -122,9 +122,9 @@ do { \
#define x86_test_and_clear_bit_percpu(bit, var) \
({ \
int old__; \
asm volatile("btr %1,"__percpu_seg_str"%c2\n\tsbbl %0,%0" \
: "=r" (old__) \
: "dIr" (bit), "i" (&per_cpu__##var) : "memory"); \
asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0" \
: "=r" (old__), "+m" (per_cpu__##var) \
: "dIr" (bit)); \
old__; \
})