- 1.44.1

[packages/fio.git] / fio-crc32c-intel.patch

--- fio-1.41.6/crc/crc32c-intel.c	2010-07-09 13:48:14.000000000 +0200
+++ fio-1.41.4/crc/crc32c-intel.c	2010-06-24 10:39:02.000000000 +0200
@@ -74,30 +74,37 @@
 	return crc;
 }
 
-static void do_cpuid(unsigned int *eax, unsigned int *ebx, unsigned int *ecx,
-		     unsigned int *edx)
+static void sig_ill(int sig)
 {
-	int id = *eax;
-
-	asm("movl %4, %%eax;"
-	    "cpuid;"
-	    "movl %%eax, %0;"
-	    "movl %%ebx, %1;"
-	    "movl %%ecx, %2;"
-	    "movl %%edx, %3;"
-		: "=r" (*eax), "=r" (*ebx), "=r" (*ecx), "=r" (*edx)
-		: "r" (id)
-		: "eax", "ebx", "ecx", "edx");
 }
 
-int crc32c_intel_works(void)
+static void crc32c_test(void)
 {
-	unsigned int eax, ebx, ecx, edx;
+	unsigned char buf[4] = { 1, 2, 3, 4 };
+	struct sigaction act;
+
+	/*
+	 * Check if hw accelerated crc32c is available
+	 */
+	memset(&act, 0, sizeof(act));
+	act.sa_handler = sig_ill;
+	act.sa_flags = SA_RESETHAND;
+	sigaction(SIGILL, &act, NULL);
 
-	eax = 1;
+	(void) crc32c_intel(buf, sizeof(buf));
+}
 
-	do_cpuid(&eax, &ebx, &ecx, &edx);
-	return (ecx & (1 << 20)) != 0;
+int crc32c_intel_works(void)
+{
+	if (!fork()) {
+		crc32c_test();
+		exit(0);
+	} else {
+		int status;
+
+		wait(&status);
+		return !WIFSIGNALED(status);
+	}
 }
 
 #endif /* ARCH_HAVE_SSE */