x86: more MTRR debug printouts

Impact: improve MTRR debugging messages

There's still inefficiencies suspected with the MTRR sanitizing
code, so make sure we get all the info we need from a dmesg.

- Remove unneeded mtrr_show

 (It will only printout one time by first cpu, so it is no big deal.)

- Also print out directly from get_mtrr, because it doesn't update mtrr_state.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B9BA5A.40108@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/cpu/mtrr/generic.c

@@ -33,14 +33,6 @@ u64 mtrr_tom2;
 struct mtrr_state_type mtrr_state = {};
 EXPORT_SYMBOL_GPL(mtrr_state);
 
-static int __initdata mtrr_show;
-static int __init mtrr_debug(char *opt)
-{
-	mtrr_show = 1;
-	return 0;
-}
-early_param("mtrr.show", mtrr_debug);
-
 /*
  * Returns the effective MTRR type for the region
  * Error returns:
@@ -193,45 +185,16 @@ static void print_fixed(unsigned base, unsigned step, const mtrr_type*types)
 	unsigned i;
 
 	for (i = 0; i < 8; ++i, ++types, base += step)
-		printk(KERN_INFO "MTRR %05X-%05X %s\n",
+		printk(KERN_INFO "  %05X-%05X %s\n",
 			base, base + step - 1, mtrr_attrib_to_str(*types));
 }
 
 static void prepare_set(void);
 static void post_set(void);
 
-/*  Grab all of the MTRR state for this CPU into *state  */
-void __init get_mtrr_state(void)
+static void __init print_mtrr_state(void)
 {
 	unsigned int i;
-	struct mtrr_var_range *vrs;
-	unsigned lo, dummy;
-	unsigned long flags;
-
-	vrs = mtrr_state.var_ranges;
-
-	rdmsr(MTRRcap_MSR, lo, dummy);
-	mtrr_state.have_fixed = (lo >> 8) & 1;
-
-	for (i = 0; i < num_var_ranges; i++)
-		get_mtrr_var_range(i, &vrs[i]);
-	if (mtrr_state.have_fixed)
-		get_fixed_ranges(mtrr_state.fixed_ranges);
-
-	rdmsr(MTRRdefType_MSR, lo, dummy);
-	mtrr_state.def_type = (lo & 0xff);
-	mtrr_state.enabled = (lo & 0xc00) >> 10;
-
-	if (amd_special_default_mtrr()) {
-		unsigned low, high;
-		/* TOP_MEM2 */
-		rdmsr(MSR_K8_TOP_MEM2, low, high);
-		mtrr_tom2 = high;
-		mtrr_tom2 <<= 32;
-		mtrr_tom2 |= low;
-		mtrr_tom2 &= 0xffffff800000ULL;
-	}
-	if (mtrr_show) {
 	int high_width;
 
 	printk(KERN_INFO "MTRR default type: %s\n", mtrr_attrib_to_str(mtrr_state.def_type));
@@ -249,7 +212,7 @@ void __init get_mtrr_state(void)
 	high_width = ((size_or_mask ? ffs(size_or_mask) - 1 : 32) - (32 - PAGE_SHIFT) + 3) / 4;
 	for (i = 0; i < num_var_ranges; ++i) {
 		if (mtrr_state.var_ranges[i].mask_lo & (1 << 11))
-				printk(KERN_INFO "MTRR %u base %0*X%05X000 mask %0*X%05X000 %s\n",
+			printk(KERN_INFO "  %u base %0*X%05X000 mask %0*X%05X000 %s\n",
 			       i,
 			       high_width,
 			       mtrr_state.var_ranges[i].base_hi,
@@ -259,13 +222,48 @@ void __init get_mtrr_state(void)
 			       mtrr_state.var_ranges[i].mask_lo >> 12,
 			       mtrr_attrib_to_str(mtrr_state.var_ranges[i].base_lo & 0xff));
 		else
-				printk(KERN_INFO "MTRR %u disabled\n", i);
+			printk(KERN_INFO "   %u disabled\n", i);
 	}
 	if (mtrr_tom2) {
 		printk(KERN_INFO "TOM2: %016llx aka %lldM\n",
 				  mtrr_tom2, mtrr_tom2>>20);
 	}
+}
+
+/*  Grab all of the MTRR state for this CPU into *state  */
+void __init get_mtrr_state(void)
+{
+	unsigned int i;
+	struct mtrr_var_range *vrs;
+	unsigned lo, dummy;
+	unsigned long flags;
+
+	vrs = mtrr_state.var_ranges;
+
+	rdmsr(MTRRcap_MSR, lo, dummy);
+	mtrr_state.have_fixed = (lo >> 8) & 1;
+
+	for (i = 0; i < num_var_ranges; i++)
+		get_mtrr_var_range(i, &vrs[i]);
+	if (mtrr_state.have_fixed)
+		get_fixed_ranges(mtrr_state.fixed_ranges);
+
+	rdmsr(MTRRdefType_MSR, lo, dummy);
+	mtrr_state.def_type = (lo & 0xff);
+	mtrr_state.enabled = (lo & 0xc00) >> 10;
+
+	if (amd_special_default_mtrr()) {
+		unsigned low, high;
+		/* TOP_MEM2 */
+		rdmsr(MSR_K8_TOP_MEM2, low, high);
+		mtrr_tom2 = high;
+		mtrr_tom2 <<= 32;
+		mtrr_tom2 |= low;
+		mtrr_tom2 &= 0xffffff800000ULL;
 	}
+
+	print_mtrr_state();
+
 	mtrr_state_set = 1;
 
 	/* PAT setup for BP. We need to go through sync steps here */
@@ -377,7 +375,12 @@ static void generic_get_mtrr(unsigned int reg, unsigned long *base,
 	unsigned int mask_lo, mask_hi, base_lo, base_hi;
 	unsigned int tmp, hi;
 
+	/*
+	 * get_mtrr doesn't need to update mtrr_state, also it could be called
+	 * from any cpu, so try to print it out directly.
+	 */
 	rdmsr(MTRRphysMask_MSR(reg), mask_lo, mask_hi);
+
 	if ((mask_lo & 0x800) == 0) {
 		/*  Invalid (i.e. free) range  */
 		*base = 0;
@@ -407,6 +410,10 @@ static void generic_get_mtrr(unsigned int reg, unsigned long *base,
 	*size = -mask_lo;
 	*base = base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT;
 	*type = base_lo & 0xff;
+
+	printk(KERN_DEBUG "  get_mtrr: cpu%d reg%02d base=%010lx size=%010lx %s\n",
+			smp_processor_id(), reg, *base, *size,
+			mtrr_attrib_to_str(*type & 0xff));
 }
 
 /**