[Xen-changelog] [xen-unstable] x86, spinlock: Get rid of .text.lock out-of-line section.

[Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>]

# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1224519475 -3600
# Node ID 7989e3999e8392751f735abe936af58443f776d7
# Parent  54d74fc0037ce688e79759ca632d3918f7aaa399
x86, spinlock: Get rid of .text.lock out-of-line section.

We don't care about code bloat now that spinlock operations are not
inlined into callers. This will make backtraces easier to read.

Signed-off-by: Keir Fraser <keir.fraser@xxxxxxxxxx>
---
 xen/arch/x86/x86_32/xen.lds.S  |    1 -
 xen/arch/x86/x86_64/xen.lds.S  |    1 -
 xen/include/asm-x86/rwlock.h   |   32 ++++++++++----------------------
 xen/include/asm-x86/spinlock.h |   17 ++++++++---------
 4 files changed, 18 insertions(+), 33 deletions(-)

diff -r 54d74fc0037c -r 7989e3999e83 xen/arch/x86/x86_32/xen.lds.S
--- a/xen/arch/x86/x86_32/xen.lds.S     Mon Oct 20 17:16:45 2008 +0100
+++ b/xen/arch/x86/x86_32/xen.lds.S     Mon Oct 20 17:17:55 2008 +0100
@@ -26,7 +26,6 @@ SECTIONS
        *(.fixup)
        *(.gnu.warning)
        } :text =0x9090
-  .text.lock : { *(.text.lock) } :text /* out-of-line lock text */
 
   _etext = .;                  /* End of text section */
 
diff -r 54d74fc0037c -r 7989e3999e83 xen/arch/x86/x86_64/xen.lds.S
--- a/xen/arch/x86/x86_64/xen.lds.S     Mon Oct 20 17:16:45 2008 +0100
+++ b/xen/arch/x86/x86_64/xen.lds.S     Mon Oct 20 17:17:55 2008 +0100
@@ -24,7 +24,6 @@ SECTIONS
        *(.fixup)
        *(.gnu.warning)
        } :text = 0x9090
-  .text.lock : { *(.text.lock) } :text /* out-of-line lock text */
 
   _etext = .;                  /* End of text section */
 
diff -r 54d74fc0037c -r 7989e3999e83 xen/include/asm-x86/rwlock.h
--- a/xen/include/asm-x86/rwlock.h      Mon Oct 20 17:16:45 2008 +0100
+++ b/xen/include/asm-x86/rwlock.h      Mon Oct 20 17:17:55 2008 +0100
@@ -22,25 +22,19 @@
 
 #define __build_read_lock_ptr(rw, helper)   \
        asm volatile(LOCK "subl $1,(%0)\n\t" \
-                    "js 2f\n" \
+                    "jns 1f\n\t" \
+                    "call " helper "\n\t" \
                     "1:\n" \
-                    ".section .text.lock,\"ax\"\n" \
-                    "2:\tcall " helper "\n\t" \
-                    "jmp 1b\n" \
-                    ".previous" \
                     ::"a" (rw) : "memory")
 
 #define __build_read_lock_const(rw, helper)   \
        asm volatile(LOCK "subl $1,%0\n\t" \
-                    "js 2f\n" \
-                    "1:\n" \
-                    ".section .text.lock,\"ax\"\n" \
-                    "2:\tpush %%"__OP"ax\n\t" \
+                    "jns 1f\n\t" \
+                    "push %%"__OP"ax\n\t" \
                     "lea %0,%%"__OP"ax\n\t" \
                     "call " helper "\n\t" \
                     "pop %%"__OP"ax\n\t" \
-                    "jmp 1b\n" \
-                    ".previous" \
+                    "1:\n" \
                     :"=m" (*(volatile int *)rw) : : "memory")
 
 #define __build_read_lock(rw, helper)  do { \
@@ -52,25 +46,19 @@
 
 #define __build_write_lock_ptr(rw, helper) \
        asm volatile(LOCK "subl $" RW_LOCK_BIAS_STR ",(%0)\n\t" \
-                    "jnz 2f\n" \
+                    "jz 1f\n\t" \
+                    "call " helper "\n\t" \
                     "1:\n" \
-                    ".section .text.lock,\"ax\"\n" \
-                    "2:\tcall " helper "\n\t" \
-                    "jmp 1b\n" \
-                    ".previous" \
                     ::"a" (rw) : "memory")
 
 #define __build_write_lock_const(rw, helper) \
        asm volatile(LOCK "subl $" RW_LOCK_BIAS_STR ",(%0)\n\t" \
-                    "jnz 2f\n" \
-                    "1:\n" \
-                    ".section .text.lock,\"ax\"\n" \
-                    "2:\tpush %%"__OP"ax\n\t" \
+                    "jz 1f\n\t" \
+                    "push %%"__OP"ax\n\t" \
                     "lea %0,%%"__OP"ax\n\t" \
                     "call " helper "\n\t" \
                     "pop %%"__OP"ax\n\t" \
-                    "jmp 1b\n" \
-                    ".previous" \
+                    "1:\n" \
                     :"=m" (*(volatile int *)rw) : : "memory")
 
 #define __build_write_lock(rw, helper) do { \
diff -r 54d74fc0037c -r 7989e3999e83 xen/include/asm-x86/spinlock.h
--- a/xen/include/asm-x86/spinlock.h    Mon Oct 20 17:16:45 2008 +0100
+++ b/xen/include/asm-x86/spinlock.h    Mon Oct 20 17:17:55 2008 +0100
@@ -18,14 +18,13 @@ static inline void _raw_spin_lock(raw_sp
 static inline void _raw_spin_lock(raw_spinlock_t *lock)
 {
     asm volatile (
-        "1:  lock; decb %0         \n"
-        "    js 2f                 \n"
-        ".section .text.lock,\"ax\"\n"
+        "1:  lock; decw %0         \n"
+        "    jns 3f                \n"
         "2:  rep; nop              \n"
-        "    cmpb $0,%0            \n"
+        "    cmpw $0,%0            \n"
         "    jle 2b                \n"
         "    jmp 1b                \n"
-        ".previous"
+        "3:"
         : "=m" (lock->lock) : : "memory" );
 }
 
@@ -33,16 +32,16 @@ static inline void _raw_spin_unlock(raw_
 {
     ASSERT(_raw_spin_is_locked(lock));
     asm volatile (
-        "movb $1,%0" 
+        "movw $1,%0" 
         : "=m" (lock->lock) : : "memory" );
 }
 
 static inline int _raw_spin_trylock(raw_spinlock_t *lock)
 {
-    char oldval;
+    s16 oldval;
     asm volatile (
-        "xchgb %b0,%1"
-        :"=q" (oldval), "=m" (lock->lock)
+        "xchgw %w0,%1"
+        :"=r" (oldval), "=m" (lock->lock)
         :"0" (0) : "memory" );
     return (oldval > 0);
 }

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