diff options
| author | peter <peter@FreeBSD.org> | 2004-02-22 02:11:39 +0000 |
|---|---|---|
| committer | peter <peter@FreeBSD.org> | 2004-02-22 02:11:39 +0000 |
| commit | 6d00d752a240fbb14fdf51e256ce843e61cb43c9 (patch) | |
| tree | 478774f8cbfbb2455bb0eed32d8a09c56df5ff8e | |
| parent | 2a9068ac03f4d66f08009d4aa0bb2ec199ae8030 (diff) | |
| download | FreeBSD-src-6d00d752a240fbb14fdf51e256ce843e61cb43c9.zip FreeBSD-src-6d00d752a240fbb14fdf51e256ce843e61cb43c9.tar.gz | |
Change the syscall stub branch orders so that the static branch prediction
will assume that syscalls will succeed rather than fail.
| -rw-r--r-- | lib/libc/amd64/SYS.h | 15 | ||||
| -rw-r--r-- | lib/libc/amd64/sys/pipe.S | 16 | ||||
| -rw-r--r-- | lib/libc/amd64/sys/reboot.S | 16 | ||||
| -rw-r--r-- | lib/libc/amd64/sys/setlogin.S | 16 |
4 files changed, 51 insertions, 12 deletions
diff --git a/lib/libc/amd64/SYS.h b/lib/libc/amd64/SYS.h index 46aeb47..844fe6a 100644 --- a/lib/libc/amd64/SYS.h +++ b/lib/libc/amd64/SYS.h @@ -41,26 +41,23 @@ #include <machine/asm.h> #ifdef PIC -#define SYSCALL(x) 2: movq PIC_GOT(HIDENAME(cerror)),%rcx; \ - jmp *%rcx; \ - ENTRY(__CONCAT(__sys_,x)); \ +#define RSYSCALL(x) ENTRY(__CONCAT(__sys_,x)); \ .weak CNAME(x); \ .set CNAME(x),CNAME(__CONCAT(__sys_,x)); \ .weak CNAME(__CONCAT(_,x)); \ .set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(__sys_,x)); \ - mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2b + mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2f; ret; \ + 2: movq PIC_GOT(HIDENAME(cerror)),%rcx; jmp *%rcx #else -#define SYSCALL(x) 2: jmp HIDENAME(cerror); \ - ENTRY(__CONCAT(__sys_,x)); \ +#define RSYSCALL(x) ENTRY(__CONCAT(__sys_,x)); \ .weak CNAME(x); \ .set CNAME(x),CNAME(__CONCAT(__sys_,x)); \ .weak CNAME(__CONCAT(_,x)); \ .set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(__sys_,x)); \ - mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2b + mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2f; ret; \ + 2: jmp HIDENAME(cerror) #endif -#define RSYSCALL(x) SYSCALL(x); ret - #define PSEUDO(x) ENTRY(__CONCAT(__sys_,x)); \ .weak CNAME(__CONCAT(_,x)); \ .set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(__sys_,x)); \ diff --git a/lib/libc/amd64/sys/pipe.S b/lib/libc/amd64/sys/pipe.S index 87bda41..4baf20c 100644 --- a/lib/libc/amd64/sys/pipe.S +++ b/lib/libc/amd64/sys/pipe.S @@ -42,8 +42,22 @@ __FBSDID("$FreeBSD$"); #include "SYS.h" -SYSCALL(pipe) + .weak _pipe + .set _pipe,__sys_pipe + .weak pipe + .set pipe,__sys_pipe +ENTRY(__sys_pipe) + mov $SYS_pipe,%rax + KERNCALL + jb 1f movl %eax,(%rdi) /* %rdi is preserved by syscall */ movl %edx,4(%rdi) movq $0,%rax ret +1: +#ifdef PIC + movq PIC_GOT(HIDENAME(cerror)),%rdx + jmp *%rdx +#else + jmp HIDENAME(cerror) +#endif diff --git a/lib/libc/amd64/sys/reboot.S b/lib/libc/amd64/sys/reboot.S index 450a65e..0ed4329 100644 --- a/lib/libc/amd64/sys/reboot.S +++ b/lib/libc/amd64/sys/reboot.S @@ -42,5 +42,19 @@ __FBSDID("$FreeBSD$"); #include "SYS.h" -SYSCALL(reboot) + .weak _reboot + .set _reboot,__sys_reboot + .weak reboot + .set reboot,__sys_reboot +ENTRY(__sys_reboot) + mov $SYS_reboot,%rax + KERNCALL + jb 1f iretq +1: +#ifdef PIC + movq PIC_GOT(HIDENAME(cerror)),%rdx + jmp *%rdx +#else + jmp HIDENAME(cerror) +#endif diff --git a/lib/libc/amd64/sys/setlogin.S b/lib/libc/amd64/sys/setlogin.S index cb355d2..439e417 100644 --- a/lib/libc/amd64/sys/setlogin.S +++ b/lib/libc/amd64/sys/setlogin.S @@ -44,7 +44,14 @@ __FBSDID("$FreeBSD$"); .globl CNAME(_logname_valid) /* in _getlogin() */ -SYSCALL(setlogin) + .weak _setlogin + .set _setlogin,__sys_setlogin + .weak setlogin + .set setlogin,__sys_setlogin +ENTRY(__sys_setlogin) + mov $SYS_setlogin,%rax + KERNCALL + jb 1f #ifdef PIC movq PIC_GOT(CNAME(_logname_valid)),%rdx movl $0,(%rdx) @@ -52,3 +59,10 @@ SYSCALL(setlogin) movl $0,CNAME(_logname_valid)(%rip) #endif ret /* setlogin(name) */ +1: +#ifdef PIC + movq PIC_GOT(HIDENAME(cerror)),%rdx + jmp *%rdx +#else + jmp HIDENAME(cerror) +#endif |
