X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/2d21ac55c334faf3a56e5634905ed6987fc787d4..0a7de7458d150b5d4dffc935ba399be265ef0a1a:/libsyscall/custom/__getpid.s

diff --git a/libsyscall/custom/__getpid.s b/libsyscall/custom/__getpid.s
index a6cc5a5f4..a8daa7398 100644
--- a/libsyscall/custom/__getpid.s
+++ b/libsyscall/custom/__getpid.s
@@ -28,51 +28,13 @@
 
 #include "SYS.h"
 
-#if defined(__ppc__) || defined(__ppc64__)
-
-        .data
-        .globl  __current_pid
-        .align  2
-__current_pid:
-        .long 0
-
-MI_ENTRY_POINT(___getpid)
-#if defined(__DYNAMIC__)
-        mflr    r0              // note we cannot use MI_GET_ADDRESS...
-        bcl    20,31,1f         // ...because we define __current_pid
-1:
-        mflr    r5
-        mtlr    r0
-        addis   r5, r5, ha16(__current_pid - 1b)
-        addi    r5, r5, lo16(__current_pid - 1b)
-#else
-	lis	r5,hi16(__current_pid)
-	ori	r5,r5,lo16(__current_pid)
-#endif
-        lwz     r3,0(r5)		// get the cached pid
-        cmpwi 	r3,0			// if positive,
-        bgtlr++                 // return it
-	
-        SYSCALL_NONAME(getpid, 0)
-
-        lwarx	r4,0,r5			// see if we can cache it
-        cmpwi	r4,0			// we can't if there are any...
-        blt--	1f              // ...vforks in progress
-
-        stwcx.	r3,0,r5			// ignore cache conflicts
-        blr
-1:
-        li      r6,-4           // on 970, cancel the reservation using red zone...
-        stwcx.  r3,r6,r1        // ...to avoid an errata
-        blr
-
-#elif defined(__i386__)
+#if defined(__i386__)
 
 	.data
 	.private_extern __current_pid
-__current_pid:
+L__current_pid_addr:
+ __current_pid:
 	.long 0
-L__current_pid_addr = __current_pid
 
 #if defined(__DYNAMIC__)
 #define GET_CURRENT_PID				\
@@ -99,7 +61,7 @@ LEAF(___getpid, 0)
 	jle		1f
 	ret
 1:
-	UNIX_SYSCALL_NONAME(getpid, 0)
+	UNIX_SYSCALL_NONAME(getpid, 0, cerror_nocancel)
 	movl		%eax, %edx
 	xorl		%eax, %eax
 	GET_CURRENT_PID
@@ -126,7 +88,7 @@ LEAF(___getpid, 0)
 	jle		1f
 	ret
 1:
-	UNIX_SYSCALL_NONAME(getpid, 0)
+	UNIX_SYSCALL_NONAME(getpid, 0, cerror_nocancel)
 	movl		%eax, %edx
 	xorl		%eax, %eax
 	leaq		__current_pid(%rip), %rcx
@@ -151,14 +113,14 @@ __current_pid:
 	 */
 	.long 0
 
-MI_ENTRY_POINT(_getpid)
+MI_ENTRY_POINT(___getpid)
 	ldr	r3, L__current_pid
 L1:	add	r3, pc, r3		// r3 = &__current_pid
 	ldr	r0, [r3]		// get the cached pid
 	cmp	r0, #0
 	bxgt	lr			// if positive, return it
 
-	SYSCALL_NONAME(getpid, 0)
+	SYSCALL_NONAME(getpid, 0, cerror_nocancel)
 
 #ifdef _ARM_ARCH_6
 	ldrex	r2, [r3]		// see if we can cache it
@@ -180,6 +142,32 @@ L1:	add	r3, pc, r3		// r3 = &__current_pid
 L__current_pid:	
 	.long	__current_pid - (L1+8)		
 
+#elif defined(__arm64__)
+	.data
+	.globl	__current_pid
+	.align 2
+__current_pid:
+	/* cached pid.  possible values:
+	 *	0:		no value cached
+	 *	> 0:		cached pid of current process
+	 *	< 0:		negative number of vforks in progress
+	 *	int_min:	for pre-armv6, "looking" value (0x80000000)
+	 */
+	.long 0
+
+MI_ENTRY_POINT(___getpid)
+	MI_GET_ADDRESS(x9, __current_pid)	// Get address of cached value
+	ldr		w0, [x9]					// Load it
+	cmp		w0, #0						// See if there's a cached value
+	b.le	L_notcached					// If not, make syscall
+	ret									// Else, we're done
+L_notcached:
+	SYSCALL_NONAME(getpid, 0, cerror_nocancel)
+	ldxr	w10, [x9]					// Exclusive load
+	cbnz	w10, L_done					// Unless unset, don't even try
+	stxr	wzr, w0, [x9]				// Try to store, but don't care if we fail (someone will win, or not)
+L_done:
+	ret									// Done
 #else
 #error Unsupported architecture
 #endif