[tip:x86/mm] x86: init_memory_mapping() trivial cleanups

From: Pekka Enberg
Date: Thu Mar 05 2009 - 08:37:41 EST


Commit-ID: c3f5d2d8b5fa6eb0cc1c47fd162bf6432f206f42
Gitweb: http://git.kernel.org/tip/c3f5d2d8b5fa6eb0cc1c47fd162bf6432f206f42
Author: "Pekka Enberg" <penberg@xxxxxxxxxxxxxx>
AuthorDate: Thu, 5 Mar 2009 14:54:52 +0200
Commit: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Thu, 5 Mar 2009 14:17:10 +0100

x86: init_memory_mapping() trivial cleanups

Impact: cleanup

To reduce the diff between the 32-bit and 64-bit versions of
init_memory_mapping(), fix up all trivial issues.

Signed-off-by: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
Cc: Yinghai Lu <yinghai@xxxxxxxxxx>
LKML-Reference: <1236257708-27269-1-git-send-email-penberg@xxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
arch/x86/mm/init_32.c | 42 +++++++++++++++++++++++++-----------------
arch/x86/mm/init_64.c | 26 +++++++++++++++-----------
2 files changed, 40 insertions(+), 28 deletions(-)

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index c351456..ad4e03c 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -868,11 +868,10 @@ static void __init find_early_table_space(unsigned long end, int use_pse)

table_start >>= PAGE_SHIFT;
table_end = table_start;
- table_top = table_start + (tables>>PAGE_SHIFT);
+ table_top = table_start + (tables >> PAGE_SHIFT);

printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
- end, table_start << PAGE_SHIFT,
- (table_start << PAGE_SHIFT) + tables);
+ end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
}

struct map_range {
@@ -899,8 +898,13 @@ static int save_mr(struct map_range *mr, int nr_range,
return nr_range;
}

+/*
+ * Setup the direct mapping of the physical memory at PAGE_OFFSET.
+ * This runs before bootmem is initialized and gets pages directly from
+ * the physical memory. To access them they are temporarily mapped.
+ */
unsigned long __init_refok init_memory_mapping(unsigned long start,
- unsigned long end)
+ unsigned long end)
{
pgd_t *pgd_base = swapper_pg_dir;
unsigned long page_size_mask = 0;
@@ -911,7 +915,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
int nr_range, i;
int use_pse;

- printk(KERN_INFO "init_memory_mapping: %08lx-%08lx\n", start, end);
+ printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);

#ifdef CONFIG_DEBUG_PAGEALLOC
/*
@@ -940,19 +944,19 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
__supported_pte_mask |= _PAGE_GLOBAL;
}

- memset(mr, 0, sizeof(mr));
- nr_range = 0;
-
if (use_pse)
page_size_mask |= 1 << PG_LEVEL_2M;

+ memset(mr, 0, sizeof(mr));
+ nr_range = 0;
+
/*
* Don't use a large page for the first 2/4MB of memory
* because there are often fixed size MTRRs in there
* and overlapping MTRRs into large pages can cause
* slowdowns.
*/
- /* head could not be big page alignment ? */
+ /* head if not big page alignment ? */
start_pfn = start >> PAGE_SHIFT;
pos = start_pfn << PAGE_SHIFT;
if (pos == 0)
@@ -960,14 +964,14 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
else
end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
<< (PMD_SHIFT - PAGE_SHIFT);
- if (end_pfn > (end>>PAGE_SHIFT))
- end_pfn = end>>PAGE_SHIFT;
+ if (end_pfn > (end >> PAGE_SHIFT))
+ end_pfn = end >> PAGE_SHIFT;
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
pos = end_pfn << PAGE_SHIFT;
}

- /* big page range */
+ /* big page (2M) range */
start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
<< (PMD_SHIFT - PAGE_SHIFT);
end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
@@ -977,7 +981,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
pos = end_pfn << PAGE_SHIFT;
}

- /* tail is not big page alignment ? */
+ /* tail is not big page (2M) alignment */
start_pfn = pos>>PAGE_SHIFT;
end_pfn = end>>PAGE_SHIFT;
if (start_pfn < end_pfn)
@@ -998,13 +1002,17 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
}

for (i = 0; i < nr_range; i++)
- printk(KERN_DEBUG " %08lx - %08lx page %s\n",
- mr[i].start, mr[i].end,
- (mr[i].page_size_mask & (1<<PG_LEVEL_2M)) ?
- "big page" : "4k");
+ printk(KERN_DEBUG " %010lx - %010lx page %s\n",
+ mr[i].start, mr[i].end,
+ (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
+ (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));

/*
* Find space for the kernel direct mapping tables.
+ *
+ * Later we should allocate these tables in the local node of the
+ * memory mapped. Unfortunately this is done currently before the
+ * nodes are discovered.
*/
if (!after_init_bootmem)
find_early_table_space(end, use_pse);
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index d325186..cdb3be1 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -554,20 +554,25 @@ static void __init find_early_table_space(unsigned long end, int use_pse,

puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
+
if (use_gbpages) {
unsigned long extra;
+
extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
} else
pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
+
tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);

if (use_pse) {
unsigned long extra;
+
extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
} else
ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);

/*
@@ -647,7 +652,6 @@ static int save_mr(struct map_range *mr, int nr_range,
unsigned long start_pfn, unsigned long end_pfn,
unsigned long page_size_mask)
{
-
if (start_pfn < end_pfn) {
if (nr_range >= NR_RANGE_MR)
panic("run out of range for init_memory_mapping\n");
@@ -679,13 +683,6 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,

printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);

- /*
- * Find space for the kernel direct mapping tables.
- *
- * Later we should allocate these tables in the local node of the
- * memory mapped. Unfortunately this is done currently before the
- * nodes are discovered.
- */
if (!after_bootmem)
init_gbpages();

@@ -709,7 +706,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
memset(mr, 0, sizeof(mr));
nr_range = 0;

- /* head if not big page alignment ?*/
+ /* head if not big page alignment ? */
start_pfn = start >> PAGE_SHIFT;
pos = start_pfn << PAGE_SHIFT;
end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
@@ -721,7 +718,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
pos = end_pfn << PAGE_SHIFT;
}

- /* big page (2M) range*/
+ /* big page (2M) range */
start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
<< (PMD_SHIFT - PAGE_SHIFT);
end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
@@ -769,7 +766,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
/* move it */
old_start = mr[i].start;
memmove(&mr[i], &mr[i+1],
- (nr_range - 1 - i) * sizeof (struct map_range));
+ (nr_range - 1 - i) * sizeof(struct map_range));
mr[i--].start = old_start;
nr_range--;
}
@@ -780,6 +777,13 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
(mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
(mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));

+ /*
+ * Find space for the kernel direct mapping tables.
+ *
+ * Later we should allocate these tables in the local node of the
+ * memory mapped. Unfortunately this is done currently before the
+ * nodes are discovered.
+ */
if (!after_bootmem)
find_early_table_space(end, use_pse, use_gbpages);

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