[PATCH] x86: mtrr cleanup for converting continuous to discrete - auto detect v4

From: Yinghai Lu
Date: Fri May 02 2008 - 05:40:43 EST



loop mtrr chunk_size and gran_size from 1M to 2G to find out optimal value.

so user don't need to add mtrr_chunk_size and mtrr_gran_size

if optimal value is not found, print out all list to help select less optimal
value.

add mtrr_spare_reg_nr= so user could set 2 instead of 1, if the card need more entries.

v2: find the one with more spare entries
v3: fix hole_basek offset
v4: tight the compare between range and range_new
loop stop with 4g

Signed-off-by: Yinghai Lu <yhlu.kernel@xxxxxxxxx>

Index: linux-2.6/arch/x86/kernel/cpu/mtrr/main.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/cpu/mtrr/main.c
+++ linux-2.6/arch/x86/kernel/cpu/mtrr/main.c
@@ -610,28 +610,6 @@ static struct sysdev_driver mtrr_sysdev_
.resume = mtrr_restore,
};

-#ifdef CONFIG_MTRR_SANITIZER
-static int enable_mtrr_cleanup __initdata = CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT;
-#else
-static int enable_mtrr_cleanup __initdata = -1;
-#endif
-
-static int __init disable_mtrr_cleanup_setup(char *str)
-{
- if (enable_mtrr_cleanup != -1)
- enable_mtrr_cleanup = 0;
- return 0;
-}
-early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup);
-
-static int __init enable_mtrr_cleanup_setup(char *str)
-{
- if (enable_mtrr_cleanup != -1)
- enable_mtrr_cleanup = 1;
- return 0;
-}
-early_param("enble_mtrr_cleanup", enable_mtrr_cleanup_setup);
-
/* should be related to MTRR_VAR_RANGES nums */
#define RANGE_NUM 256

@@ -702,13 +680,15 @@ subtract_range(struct res_range *range,
continue;
}

- if (start <= range[j].start && end < range[j].end && range[j].start < end + 1) {
+ if (start <= range[j].start && end < range[j].end &&
+ range[j].start < end + 1) {
range[j].start = end + 1;
continue;
}


- if (start > range[j].start && end >= range[j].end && range[j].end > start - 1) {
+ if (start > range[j].start && end >= range[j].end &&
+ range[j].end > start - 1) {
range[j].end = start - 1;
continue;
}
@@ -743,18 +723,123 @@ static int __init cmp_range(const void *
return start1 - start2;
}

+struct var_mtrr_range_state {
+ unsigned long base_pfn;
+ unsigned long size_pfn;
+ mtrr_type type;
+};
+
+struct var_mtrr_range_state __initdata range_state[RANGE_NUM];
+
+static int __init
+x86_get_mtrr_mem_range(struct res_range *range, int nr_range,
+ unsigned long extra_remove_base,
+ unsigned long extra_remove_size)
+{
+ unsigned long i, base, size;
+ mtrr_type type;
+
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
+ if (type != MTRR_TYPE_WRBACK)
+ continue;
+ base = range_state[i].base_pfn;
+ size = range_state[i].size_pfn;
+ nr_range = add_range_with_merge(range, nr_range, base,
+ base + size - 1);
+ }
+ printk(KERN_DEBUG "After WB checking\n");
+ for (i = 0; i < nr_range; i++)
+ printk(KERN_DEBUG "MTRR MAP PFN: %016lx - %016lx\n",
+ range[i].start, range[i].end + 1);
+
+ /* take out UC ranges */
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
+ if (type != MTRR_TYPE_UNCACHABLE)
+ continue;
+ size = range_state[i].size_pfn;
+ if (!size)
+ continue;
+ base = range_state[i].base_pfn;
+ subtract_range(range, base, base + size - 1);
+ }
+ if (extra_remove_size)
+ subtract_range(range, extra_remove_base,
+ extra_remove_base + extra_remove_size - 1);
+
+ /* get new range num */
+ nr_range = 0;
+ for (i = 0; i < RANGE_NUM; i++) {
+ if (!range[i].end)
+ continue;
+ nr_range++;
+ }
+ printk(KERN_DEBUG "After UC checking\n");
+ for (i = 0; i < nr_range; i++)
+ printk(KERN_DEBUG "MTRR MAP PFN: %016lx - %016lx\n",
+ range[i].start, range[i].end + 1);
+
+ /* sort the ranges */
+ sort(range, nr_range, sizeof(struct res_range), cmp_range, NULL);
+ printk(KERN_DEBUG "After sorting\n");
+ for (i = 0; i < nr_range; i++)
+ printk(KERN_DEBUG "MTRR MAP PFN: %016lx - %016lx\n",
+ range[i].start, range[i].end + 1);
+
+ /* clear those is not used */
+ for (i = nr_range; i < RANGE_NUM; i++)
+ memset(&range[i], 0, sizeof(range[i]));
+
+ return nr_range;
+}
+
+static struct res_range __initdata range[RANGE_NUM];
+
+#ifdef CONFIG_MTRR_SANITIZER
+
+static unsigned long __init sum_ranges(struct res_range *range, int nr_range)
+{
+ unsigned long sum;
+ int i;
+
+ sum = 0;
+ for (i = 0; i < nr_range; i++)
+ sum += range[i].end + 1 - range[i].start;
+
+ return sum;
+}
+
+static int enable_mtrr_cleanup __initdata =
+ CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT;
+
+static int __init disable_mtrr_cleanup_setup(char *str)
+{
+ if (enable_mtrr_cleanup != -1)
+ enable_mtrr_cleanup = 0;
+ return 0;
+}
+early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup);
+
+static int __init enable_mtrr_cleanup_setup(char *str)
+{
+ if (enable_mtrr_cleanup != -1)
+ enable_mtrr_cleanup = 1;
+ return 0;
+}
+early_param("enble_mtrr_cleanup", enable_mtrr_cleanup_setup);
+
struct var_mtrr_state {
unsigned long range_startk;
unsigned long range_sizek;
unsigned long chunk_sizek;
unsigned long gran_sizek;
unsigned int reg;
- unsigned int address_bits;
};

static void __init
set_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
- unsigned char type, unsigned address_bits)
+ unsigned char type, unsigned int address_bits)
{
u32 base_lo, base_hi, mask_lo, mask_hi;
u64 base, mask;
@@ -781,10 +866,34 @@ set_var_mtrr(unsigned int reg, unsigned
fill_mtrr_var_range(reg, base_lo, base_hi, mask_lo, mask_hi);
}

+static void __init
+save_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
+ unsigned char type)
+{
+ range_state[reg].base_pfn = basek >> (PAGE_SHIFT - 10);
+ range_state[reg].size_pfn = sizek >> (PAGE_SHIFT - 10);
+ range_state[reg].type = type;
+}
+
+static void __init
+set_var_mtrr_all(unsigned int address_bits)
+{
+ unsigned long basek, sizek;
+ unsigned char type;
+ unsigned int reg;
+
+ for (reg = 0; reg < num_var_ranges; reg++) {
+ basek = range_state[reg].base_pfn << (PAGE_SHIFT - 10);
+ sizek = range_state[reg].size_pfn << (PAGE_SHIFT - 10);
+ type = range_state[reg].type;
+
+ set_var_mtrr(reg, basek, sizek, type, address_bits);
+ }
+}
+
static unsigned int __init
range_to_mtrr(unsigned int reg, unsigned long range_startk,
- unsigned long range_sizek, unsigned char type,
- unsigned address_bits)
+ unsigned long range_sizek, unsigned char type)
{
if (!range_sizek || (reg >= num_var_ranges))
return reg;
@@ -803,12 +912,12 @@ range_to_mtrr(unsigned int reg, unsigned
align = max_align;

sizek = 1 << align;
- printk(KERN_INFO "Setting variable MTRR %d, base: %ldMB, range: %ldMB, type %s\n",
+ printk(KERN_DEBUG "Setting variable MTRR %d, base: %ldMB, range: %ldMB, type %s\n",
reg, range_startk >> 10, sizek >> 10,
(type == MTRR_TYPE_UNCACHABLE)?"UC":
((type == MTRR_TYPE_WRBACK)?"WB":"Other")
);
- set_var_mtrr(reg++, range_startk, sizek, type, address_bits);
+ save_var_mtrr(reg++, range_startk, sizek, type);
range_startk += sizek;
range_sizek -= sizek;
if (reg >= num_var_ranges)
@@ -817,10 +926,12 @@ range_to_mtrr(unsigned int reg, unsigned
return reg;
}

-static void __init
-range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek)
+static unsigned __init
+range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek,
+ unsigned long sizek)
{
unsigned long hole_basek, hole_sizek;
+ unsigned long second_basek, second_sizek;
unsigned long range0_basek, range0_sizek;
unsigned long range_basek, range_sizek;
unsigned long chunk_sizek;
@@ -828,64 +939,91 @@ range_to_mtrr_with_hole(struct var_mtrr_

hole_basek = 0;
hole_sizek = 0;
+ second_basek = 0;
+ second_sizek = 0;
chunk_sizek = state->chunk_sizek;
gran_sizek = state->gran_sizek;

/* align with gran size, prevent small block used up MTRRs */
range_basek = ALIGN(state->range_startk, gran_sizek);
if ((range_basek > basek) && basek)
- return;
- range_sizek = ALIGN(state->range_sizek - (range_basek - state->range_startk), gran_sizek);
+ return second_sizek;
+ state->range_sizek -= (range_basek - state->range_startk);
+ range_sizek = ALIGN(state->range_sizek, gran_sizek);

- while (range_basek + range_sizek > (state->range_startk + state->range_sizek)) {
+ while (range_sizek > state->range_sizek) {
range_sizek -= gran_sizek;
if (!range_sizek)
- return;
+ return 0;
}
- state->range_startk = range_basek;
state->range_sizek = range_sizek;

/* try to append some small hole */
range0_basek = state->range_startk;
range0_sizek = ALIGN(state->range_sizek, chunk_sizek);
if (range0_sizek == state->range_sizek) {
- printk(KERN_INFO "rangeX: %016lx - %016lx\n", range0_basek<<10, (range0_basek + state->range_sizek)<<10);
- state->reg = range_to_mtrr(state->reg, range0_basek,
- state->range_sizek, MTRR_TYPE_WRBACK, state->address_bits);
- return;
- } else if (basek) {
- while (range0_basek + range0_sizek - chunk_sizek > basek) {
+ printk(KERN_DEBUG "rangeX: %016lx - %016lx\n", range0_basek<<10,
+ (range0_basek + state->range_sizek)<<10);
+ state->reg = range_to_mtrr(state->reg, range0_basek,
+ state->range_sizek, MTRR_TYPE_WRBACK);
+ return 0;
+ }
+
+ range0_sizek -= chunk_sizek;
+ if (range0_sizek && sizek) {
+ while (range0_basek + range0_sizek > (basek + sizek)) {
range0_sizek -= chunk_sizek;
if (!range0_sizek)
break;
}
}

+ if (range0_sizek) {
+ printk(KERN_DEBUG "range0: %016lx - %016lx\n", range0_basek<<10,
+ (range0_basek + range0_sizek)<<10);
+ state->reg = range_to_mtrr(state->reg, range0_basek,
+ range0_sizek, MTRR_TYPE_WRBACK);

- if (range0_sizek > chunk_sizek)
- range0_sizek -= chunk_sizek;
- printk(KERN_INFO "range0: %016lx - %016lx\n", range0_basek<<10, (range0_basek + range0_sizek)<<10);
- state->reg = range_to_mtrr(state->reg, range0_basek,
- range0_sizek, MTRR_TYPE_WRBACK, state->address_bits);
+ }

range_basek = range0_basek + range0_sizek;
range_sizek = chunk_sizek;

- if ((range_sizek - (state->range_sizek - range0_sizek) < (chunk_sizek >> 1)) &&
- (range_basek + range_sizek <= basek)) {
- hole_sizek = range_sizek - (state->range_sizek - range0_sizek);
- hole_basek = range_basek + range_sizek - hole_sizek;
- } else
+ if (range_basek + range_sizek > basek &&
+ range_basek + range_sizek <= (basek + sizek)) {
+ /* one hole */
+ second_basek = basek;
+ second_sizek = range_basek + range_sizek - basek;
+ }
+
+ /* if last piece, only could one hole near end */
+ if ((second_basek || !basek) &&
+ range_sizek - (state->range_sizek - range0_sizek) - second_sizek < (chunk_sizek >> 1)) {
+ /* one hole in middle (second_sizek is 0) or at end (second_sizek is 0 ) */
+ hole_sizek = range_sizek - (state->range_sizek - range0_sizek)
+ - second_sizek;
+ hole_basek = range_basek + range_sizek - hole_sizek
+ - second_sizek;
+ } else {
+ /* fallback for big hole, or several holes */
range_sizek = state->range_sizek - range0_sizek;
+ second_basek = 0;
+ second_sizek = 0;
+ }

- printk(KERN_INFO "range: %016lx - %016lx\n", range_basek<<10, (range_basek + range_sizek)<<10);
- state->reg = range_to_mtrr(state->reg, range_basek,
- range_sizek, MTRR_TYPE_WRBACK, state->address_bits);
+ printk(KERN_DEBUG "range: %016lx - %016lx\n", range_basek<<10,
+ (range_basek + range_sizek)<<10);
+ state->reg = range_to_mtrr(state->reg, range_basek, range_sizek,
+ MTRR_TYPE_WRBACK);
if (hole_sizek) {
- printk(KERN_INFO "hole: %016lx - %016lx\n", hole_basek<<10, (hole_basek + hole_sizek)<<10);
- state->reg = range_to_mtrr(state->reg, hole_basek,
- hole_sizek, MTRR_TYPE_UNCACHABLE, state->address_bits);
+ printk(KERN_DEBUG "hole: %016lx - %016lx\n", hole_basek<<10,
+ (hole_basek + hole_sizek)<<10);
+ state->reg = range_to_mtrr(state->reg, hole_basek, hole_sizek,
+ MTRR_TYPE_UNCACHABLE);
+
}
+
+ return second_sizek;
}

static void __init
@@ -893,6 +1031,7 @@ set_var_mtrr_range(struct var_mtrr_state
unsigned long size_pfn)
{
unsigned long basek, sizek;
+ unsigned long second_sizek = 0;

if (state->reg >= num_var_ranges)
return;
@@ -901,21 +1040,19 @@ set_var_mtrr_range(struct var_mtrr_state
sizek = size_pfn << (PAGE_SHIFT - 10);

/* See if I can merge with the last range */
- if ((basek <= 1024) || (state->range_startk + state->range_sizek == basek)) {
+ if ((basek <= 1024) ||
+ (state->range_startk + state->range_sizek == basek)) {
unsigned long endk = basek + sizek;
state->range_sizek = endk - state->range_startk;
return;
}
/* Write the range mtrrs */
- if (state->range_sizek != 0) {
- range_to_mtrr_with_hole(state, basek);
+ if (state->range_sizek != 0)
+ second_sizek = range_to_mtrr_with_hole(state, basek, sizek);

- state->range_startk = 0;
- state->range_sizek = 0;
- }
/* Allocate an msr */
- state->range_startk = basek;
- state->range_sizek = sizek;
+ state->range_startk = basek + second_sizek;
+ state->range_sizek = sizek - second_sizek;
}

/* mininum size of mtrr block that can take hole */
@@ -931,7 +1068,7 @@ static int __init parse_mtrr_chunk_size_
early_param("mtrr_chunk_size", parse_mtrr_chunk_size_opt);

/* granity of mtrr of block */
-static u64 mtrr_gran_size __initdata = (1ULL<<20);
+static u64 mtrr_gran_size __initdata;

static int __init parse_mtrr_gran_size_opt(char *p)
{
@@ -942,91 +1079,79 @@ static int __init parse_mtrr_gran_size_o
}
early_param("mtrr_gran_size", parse_mtrr_gran_size_opt);

-static void __init
+static int nr_mtrr_spare_reg __initdata =
+ CONFIG_MTRR_SANITIZER_SPARE_REG_NR_DEFAULT;
+
+static int __init parse_mtrr_spare_reg(char *arg)
+{
+ if (arg)
+ nr_mtrr_spare_reg = simple_strtoul(arg, NULL, 0);
+ return 0;
+}
+
+early_param("mtrr_spare_reg_nr", parse_mtrr_spare_reg);
+
+static int __init
x86_setup_var_mtrrs(struct res_range *range, int nr_range,
- unsigned address_bits)
+ u64 chunk_size, u64 gran_size)
{
struct var_mtrr_state var_state;
int i;
+ int num_reg;

var_state.range_startk = 0;
var_state.range_sizek = 0;
var_state.reg = 0;
- var_state.address_bits = address_bits;
- var_state.chunk_sizek = mtrr_chunk_size >> 10;
- var_state.gran_sizek = mtrr_gran_size >> 10;
+ var_state.chunk_sizek = chunk_size >> 10;
+ var_state.gran_sizek = gran_size >> 10;
+
+ memset(range_state, 0, sizeof(range_state));

/* Write the range etc */
for (i = 0; i < nr_range; i++)
- set_var_mtrr_range(&var_state, range[i].start, range[i].end - range[i].start + 1);
+ set_var_mtrr_range(&var_state, range[i].start,
+ range[i].end - range[i].start + 1);

/* Write the last range */
- range_to_mtrr_with_hole(&var_state, 0);
- printk(KERN_INFO "DONE variable MTRRs\n");
+ if (var_state.range_sizek != 0)
+ range_to_mtrr_with_hole(&var_state, 0, 0);
+ printk(KERN_DEBUG "DONE variable MTRRs\n");
+
+ num_reg = var_state.reg;
/* Clear out the extra MTRR's */
while (var_state.reg < num_var_ranges) {
- set_var_mtrr(var_state.reg, 0, 0, 0, var_state.address_bits);
+ save_var_mtrr(var_state.reg, 0, 0, 0);
var_state.reg++;
}
-}

-static int __init
-x86_get_mtrr_mem_range(struct res_range *range, int nr_range,
- unsigned long extra_remove_base,
- unsigned long extra_remove_size)
-{
- unsigned long i, base, size;
- mtrr_type type;
-
- for (i = 0; i < num_var_ranges; i++) {
- mtrr_if->get(i, &base, &size, &type);
- if (type != MTRR_TYPE_WRBACK)
- continue;
- nr_range = add_range_with_merge(range, nr_range, base, base + size - 1);
- }
- printk(KERN_INFO "After WB checking\n");
- for (i = 0; i < nr_range; i++)
- printk(KERN_INFO "MTRR MAP PFN: %016lx - %016lx\n", range[i].start, range[i].end + 1);
-
- /* take out UC ranges */
- for (i = 0; i < num_var_ranges; i++) {
- mtrr_if->get(i, &base, &size, &type);
- if (type != MTRR_TYPE_UNCACHABLE)
- continue;
- if (!size)
- continue;
- subtract_range(range, base, base + size - 1);
- }
- if (extra_remove_size)
- subtract_range(range, extra_remove_base, extra_remove_base + extra_remove_size - 1);
+ return num_reg;
+}

- /* get new range num */
- nr_range = 0;
- for (i = 0; i < RANGE_NUM; i++) {
- if (!range[i].end)
- continue;
- nr_range++;
- }
- printk(KERN_INFO "After UC checking\n");
- for (i = 0; i < nr_range; i++)
- printk(KERN_INFO "MTRR MAP PFN: %016lx - %016lx\n", range[i].start, range[i].end + 1);
+struct mtrr_cleanup_result {
+ unsigned long gran_sizek;
+ unsigned long chunk_sizek;
+ unsigned long lose_cover_sizek;
+ unsigned int num_reg;
+ int bad;
+};

- /* sort the ranges */
- sort(range, nr_range, sizeof(struct res_range), cmp_range, NULL);
- printk(KERN_INFO "After sorting\n");
- for (i = 0; i < nr_range; i++)
- printk(KERN_INFO "MTRR MAP PFN: %016lx - %016lx\n", range[i].start, range[i].end + 1);
+/* gran_size: 1M, 2M, ..., 2G, chunk size: gran_size, ..., 4G. so need (2+13)*6 */
+#define NUM_RESULT 90

- return nr_range;
-}
+static struct mtrr_cleanup_result __initdata result[NUM_RESULT];
+static struct res_range __initdata range_new[RANGE_NUM];
+static unsigned long __initdata min_loss_pfn[RANGE_NUM];

static int __init mtrr_cleanup(unsigned address_bits)
{
unsigned long extra_remove_base, extra_remove_size;
unsigned long i, base, size, def, dummy;
- struct res_range range[RANGE_NUM];
mtrr_type type;
- int nr_range;
+ int nr_range, nr_range_new;
+ u64 chunk_size, gran_size;
+ unsigned long range_sums, range_sums_new;
+ int index_good;
+ int num_reg_good;

/* extra one for all 0 */
int num[MTRR_NUM_TYPES + 1];
@@ -1038,10 +1163,20 @@ static int __init mtrr_cleanup(unsigned
if (def != MTRR_TYPE_UNCACHABLE)
return 0;

+ /* get it and store it aside */
+ memset(range_state, 0, sizeof(range_state));
+ for (i = 0; i < num_var_ranges; i++) {
+ mtrr_if->get(i, &base, &size, &type);
+ range_state[i].base_pfn = base;
+ range_state[i].size_pfn = size;
+ range_state[i].type = type;
+ }
+
/* check entries number */
memset(num, 0, sizeof(num));
for (i = 0; i < num_var_ranges; i++) {
- mtrr_if->get(i, &base, &size, &type);
+ type = range_state[i].type;
+ size = range_state[i].size_pfn;
if (type >= MTRR_NUM_TYPES)
continue;
if (!size)
@@ -1064,13 +1199,159 @@ static int __init mtrr_cleanup(unsigned
extra_remove_base = 1 << (32 - PAGE_SHIFT);
extra_remove_size = (mtrr_tom2>>PAGE_SHIFT) - extra_remove_base;
}
- nr_range = x86_get_mtrr_mem_range(range, 0, extra_remove_base, extra_remove_size);
+ nr_range = x86_get_mtrr_mem_range(range, 0, extra_remove_base,
+ extra_remove_size);
+ range_sums = sum_ranges(range, nr_range);
+ printk(KERN_INFO "total RAM coverred: %ldM\n",
+ range_sums >> (20 - PAGE_SHIFT));
+
+ if (mtrr_chunk_size && mtrr_gran_size) {
+ int num_reg;
+
+ /* convert ranges to var ranges state */
+ num_reg = x86_setup_var_mtrrs(range, nr_range, mtrr_chunk_size,
+ mtrr_gran_size);
+
+ /* we got new setting in range_state, check it */
+ memset(range_new, 0, sizeof(range_new));
+ nr_range_new = x86_get_mtrr_mem_range(range_new, 0,
+ extra_remove_base, extra_remove_size);
+ range_sums_new = sum_ranges(range_new, nr_range_new);
+
+ i = 0;
+ result[i].chunk_sizek = mtrr_chunk_size >> 10;
+ result[i].gran_sizek = mtrr_gran_size >> 10;
+ result[i].num_reg = num_reg;
+ if (range_sums < range_sums_new) {
+ result[i].lose_cover_sizek = (range_sums_new - range_sums) << (PAGE_SHIFT - 10);
+ result[i].bad = 1;
+ } else
+ result[i].lose_cover_sizek = (range_sums - range_sums_new) << (PAGE_SHIFT - 10);
+
+ printk(KERN_INFO " %sgran_size: %ldM \tchunk_size: %ldM \t",
+ result[i].bad?" BAD ":"", result[i].gran_sizek >> 10,
+ result[i].chunk_sizek >> 10);
+ printk(KERN_CONT "num_reg: %d \tlose cover RAM: %s%ldM \n",
+ result[i].num_reg, result[i].bad?"-":"",
+ result[i].lose_cover_sizek >> 10);
+ if (!result[i].bad) {
+ set_var_mtrr_all(address_bits);
+ return 1;
+ }
+ printk(KERN_INFO "invalid mtrr_gran_size or mtrr_chunk_size, will find optimal one\n");
+ memset(result, 0, sizeof(result[0]));
+ }
+
+ i = 0;
+ memset(min_loss_pfn, 0xff, sizeof(min_loss_pfn));
+ memset(result, 0, sizeof(result));
+ for (gran_size = (1ULL<<20); gran_size < (1ULL<<32); gran_size <<= 1) {
+ for (chunk_size = gran_size; chunk_size < (1ULL<<33);
+ chunk_size <<= 1) {
+ int num_reg;
+
+ printk(KERN_INFO "\ngran_size: %lldM chunk_size_size: %lldM\n", gran_size >> 20, chunk_size >> 20);
+ if (i >= NUM_RESULT)
+ continue;
+
+ /* convert ranges to var ranges state */
+ num_reg = x86_setup_var_mtrrs(range, nr_range,
+ chunk_size, gran_size);
+
+ /* we got new setting in range_state, check it */
+ memset(range_new, 0, sizeof(range_new));
+ nr_range_new = x86_get_mtrr_mem_range(range_new, 0,
+ extra_remove_base, extra_remove_size);
+ range_sums_new = sum_ranges(range_new, nr_range_new);
+
+ result[i].chunk_sizek = chunk_size >> 10;
+ result[i].gran_sizek = gran_size >> 10;
+ result[i].num_reg = num_reg;
+ if (range_sums < range_sums_new) {
+ result[i].lose_cover_sizek = (range_sums_new - range_sums) << (PAGE_SHIFT - 10);
+ result[i].bad = 1;
+ } else
+ result[i].lose_cover_sizek = (range_sums - range_sums_new) << (PAGE_SHIFT - 10);
+
+ /* double check it */
+ if (!result[i].bad && !result[i].lose_cover_sizek) {
+ if (nr_range_new != nr_range ||
+ memcmp(range, range_new, sizeof(range)))
+ result[i].bad = 1;
+ }
+
+ if (!result[i].bad && (range_sums - range_sums_new <
+ min_loss_pfn[num_reg]))
+ min_loss_pfn[num_reg] = range_sums - range_sums_new;
+ i++;
+ }
+ }

- /* convert ranges to var ranges state */
- x86_setup_var_mtrrs(range, nr_range, address_bits);
+ /* print out all */
+ for (i = 0; i < NUM_RESULT; i++) {
+ printk(KERN_INFO "%sgran_size: %ldM \tchunk_size: %ldM \t",
+ result[i].bad?"*BAD* ":" ", result[i].gran_sizek >> 10,
+ result[i].chunk_sizek >> 10);
+ printk(KERN_CONT "num_reg: %d \tlose cover RAM: %s%ldM \n",
+ result[i].num_reg, result[i].bad?"-":"",
+ result[i].lose_cover_sizek >> 10);
+ }
+
+ /* try to find the optimal index */
+ if (nr_mtrr_spare_reg >= num_var_ranges)
+ nr_mtrr_spare_reg = num_var_ranges - 1;
+ num_reg_good = -1;
+ for (i = 1; i < num_var_ranges + 1 - nr_mtrr_spare_reg; i++) {
+ if (!min_loss_pfn[i]) {
+ num_reg_good = i;
+ break;
+ }
+ }
+
+ index_good = -1;
+ if (num_reg_good != -1) {
+ for (i = 0; i < NUM_RESULT; i++) {
+ if (!result[i].bad &&
+ result[i].num_reg == num_reg_good &&
+ !result[i].lose_cover_sizek) {
+ index_good = i;
+ break;
+ }
+ }
+ }

- return 1;
+ if (index_good != -1) {
+ printk(KERN_INFO "Found optimal setting for mtrr clean up\n");
+ i = index_good;
+ printk(KERN_INFO "gran_size: %ldM \tchunk_size: %ldM \t",
+ result[i].gran_sizek >> 10,
+ result[i].chunk_sizek >> 10);
+ printk(KERN_CONT "num_reg: %d \tlose cover RAM: %ldM \n",
+ result[i].num_reg,
+ result[i].lose_cover_sizek >> 10);
+ /* convert ranges to var ranges state */
+ chunk_size = result[i].chunk_sizek;
+ chunk_size <<= 10;
+ gran_size = result[i].gran_sizek;
+ gran_size <<= 10;
+ x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
+ set_var_mtrr_all(address_bits);
+ return 1;
+ }
+
+ printk(KERN_INFO "mtrr_cleanup: can not find optimal value\n");
+ printk(KERN_INFO "please specify mtrr_gran_size/mtrr_chunk_size\n");
+
+ return 0;
+}
+#else
+static int __init mtrr_cleanup(unsigned address_bits)
+{
+ return 0;
}
+#endif
+
+static int __initdata changed_by_mtrr_cleanup;

static int disable_mtrr_trim;

@@ -1111,7 +1392,8 @@ int __init amd_special_default_mtrr(void
return 0;
}

-static u64 __init real_trim_memory(unsigned long start_pfn, unsigned long limit_pfn)
+static u64 __init real_trim_memory(unsigned long start_pfn,
+ unsigned long limit_pfn)
{
u64 trim_start, trim_size;
trim_start = start_pfn;
@@ -1138,9 +1420,8 @@ int __init mtrr_trim_uncached_memory(uns
{
unsigned long i, base, size, highest_pfn = 0, def, dummy;
mtrr_type type;
- struct res_range range[RANGE_NUM];
int nr_range;
- u64 total_real_trim_size;
+ u64 total_trim_size;

/* extra one for all 0 */
int num[MTRR_NUM_TYPES + 1];
@@ -1155,11 +1436,22 @@ int __init mtrr_trim_uncached_memory(uns
if (def != MTRR_TYPE_UNCACHABLE)
return 0;

- /* Find highest cached pfn */
+ /* get it and store it aside */
+ memset(range_state, 0, sizeof(range_state));
for (i = 0; i < num_var_ranges; i++) {
mtrr_if->get(i, &base, &size, &type);
+ range_state[i].base_pfn = base;
+ range_state[i].size_pfn = size;
+ range_state[i].type = type;
+ }
+
+ /* Find highest cached pfn */
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
if (type != MTRR_TYPE_WRBACK)
continue;
+ base = range_state[i].base_pfn;
+ size = range_state[i].size_pfn;
if (highest_pfn < base + size)
highest_pfn = base + size;
}
@@ -1177,9 +1469,10 @@ int __init mtrr_trim_uncached_memory(uns
/* check entries number */
memset(num, 0, sizeof(num));
for (i = 0; i < num_var_ranges; i++) {
- mtrr_if->get(i, &base, &size, &type);
+ type = range_state[i].type;
if (type >= MTRR_NUM_TYPES)
continue;
+ size = range_state[i].size_pfn;
if (!size)
type = MTRR_NUM_TYPES;
num[type]++;
@@ -1205,26 +1498,28 @@ int __init mtrr_trim_uncached_memory(uns
}
nr_range = x86_get_mtrr_mem_range(range, nr_range, 0, 0);

- total_real_trim_size = 0;
+ total_trim_size = 0;
/* check the head */
if (range[0].start)
- total_real_trim_size += real_trim_memory(0, range[0].start);
+ total_trim_size += real_trim_memory(0, range[0].start);
/* check the holes */
for (i = 0; i < nr_range - 1; i++) {
if (range[i].end + 1 < range[i+1].start)
- total_real_trim_size += real_trim_memory(range[i].end + 1, range[i+1].start);
+ total_trim_size += real_trim_memory(range[i].end + 1,
+ range[i+1].start);
}
/* check the top */
i = nr_range - 1;
if (range[i].end + 1 < end_pfn)
- total_real_trim_size += real_trim_memory(range[i].end + 1, end_pfn);
+ total_trim_size += real_trim_memory(range[i].end + 1,
+ end_pfn);

- if (total_real_trim_size) {
+ if (total_trim_size) {
printk(KERN_WARNING "WARNING: BIOS bug: CPU MTRRs don't cover"
" all of memory, losing %lluMB of RAM.\n",
- total_real_trim_size >> 20);
+ total_trim_size >> 20);

- if (enable_mtrr_cleanup < 1)
+ if (!changed_by_mtrr_cleanup)
WARN_ON(1);

printk(KERN_INFO "update e820 for mtrr\n");
@@ -1314,8 +1609,10 @@ void __init mtrr_bp_init(void)
if (use_intel()) {
get_mtrr_state();

- if (mtrr_cleanup(phys_addr))
+ if (mtrr_cleanup(phys_addr)) {
+ changed_by_mtrr_cleanup = 1;
mtrr_if->set_all();
+ }

}
}
@@ -1355,7 +1652,7 @@ static int __init mtrr_init_finialize(vo
if (!mtrr_if)
return 0;
if (use_intel()) {
- if (enable_mtrr_cleanup < 1)
+ if (!changed_by_mtrr_cleanup)
mtrr_state_warn();
} else {
/* The CPUs haven't MTRR and seem to not support SMP. They have
Index: linux-2.6/Documentation/kernel-parameters.txt
===================================================================
--- linux-2.6.orig/Documentation/kernel-parameters.txt
+++ linux-2.6/Documentation/kernel-parameters.txt
@@ -613,8 +613,17 @@ and is between 256 and 4096 characters.
that could hold holes aka. UC entries.

mtrr_gran_size=nn[KMG] [X86]
- used for mtrr cleanup. It is granity of mtrr block.
- Big value could prevent small alignment use up MTRRs.
+ Used for mtrr cleanup. It is granularity of mtrr block.
+ Default is 1.
+ Large value could prevent small alignment from
+ using up MTRRs.
+
+ mtrr_spare_reg_nr=n [X86]
+ Format: <integer>
+ Range: 0,7 : spare reg number
+ Default : 1
+ Used for mtrr cleanup. It is spare mtrr entries number.
+ Set to 2 or more if your graphical card needs more.

disable_mtrr_trim [X86, Intel and AMD only]
By default the kernel will trim any uncacheable
Index: linux-2.6/arch/x86/Kconfig
===================================================================
--- linux-2.6.orig/arch/x86/Kconfig
+++ linux-2.6/arch/x86/Kconfig
@@ -1100,6 +1100,15 @@ config MTRR_SANITIZER_ENABLE_DEFAULT
help
Enable mtrr cleanup default value

+config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
+ int "MTRR cleanup spare reg num (0-7)"
+ range 0 7
+ default "1"
+ depends on MTRR_SANITIZER
+ help
+ mtrr cleanup spare entries default, it can be changed via
+ mtrr_spare_reg_nr=
+
config X86_PAT
bool
prompt "x86 PAT support"
--
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