intel-agp: Switch to wbinvd_on_all_cpus

Simplify if-statement while at it.

[ hpa: we need to #include <asm/smp.h> ]

Cc: Dave Jones <davej@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <1264172467-25155-3-git-send-email-bp@amd64.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

drivers/char/agp/intel-agp.c

@@ -8,6 +8,7 @@
 #include <linux/kernel.h>
 #include <linux/pagemap.h>
 #include <linux/agp_backend.h>
+#include <asm/smp.h>
 #include "agp.h"
 
 /*
@@ -815,12 +816,6 @@ static void intel_i830_setup_flush(void)
 		intel_i830_fini_flush();
 }
 
-static void
-do_wbinvd(void *null)
-{
-	wbinvd();
-}
-
 /* The chipset_flush interface needs to get data that has already been
  * flushed out of the CPU all the way out to main memory, because the GPU
  * doesn't snoop those buffers.
@@ -837,12 +832,10 @@ static void intel_i830_chipset_flush(struct agp_bridge_data *bridge)
 
 	memset(pg, 0, 1024);
 
-	if (cpu_has_clflush) {
+	if (cpu_has_clflush)
 		clflush_cache_range(pg, 1024);
-	} else {
-		if (on_each_cpu(do_wbinvd, NULL, 1) != 0)
-			printk(KERN_ERR "Timed out waiting for cache flush.\n");
-	}
+	else if (wbinvd_on_all_cpus() != 0)
+		printk(KERN_ERR "Timed out waiting for cache flush.\n");
 }
 
 /* The intel i830 automatically initializes the agp aperture during POST.