Commit 441ac2f3 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

x86/boot/e820: Simplify e820__update_table() 



 - Remove the now unnecessary __e820__update_table() wrappery

 - Move statics out from function scope, to make the logic clearer

 - Rename local variables to be more in line with the rest of 820.c

 - Remove unnecessary local variables: old_nr, *nr_entries

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 7410aa1c

arch/x86/kernel/e820.c

+31 −39
Original line number Original line Diff line number Diff line
@@ -235,6 +235,11 @@ struct change_member { 
	unsigned long long	addr;

	unsigned long long	addr;

};

};





static struct change_member	change_point_list[2*E820_MAX_ENTRIES]	__initdata;

static struct change_member	*change_point[2*E820_MAX_ENTRIES]	__initdata;

static struct e820_entry	*overlap_list[E820_MAX_ENTRIES]		__initdata;

static struct e820_entry	new_entries[E820_MAX_ENTRIES]		__initdata;



static int __init cpcompare(const void *a, const void *b)

static int __init cpcompare(const void *a, const void *b)

{

{

	struct change_member * const *app = a, * const *bpp = b;

	struct change_member * const *app = a, * const *bpp = b;
@@ -252,51 +257,46 @@ static int __init cpcompare(const void *a, const void *b) 
	return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr);

	return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr);

}

}





static int __init __e820__update_table(struct e820_entry *entries, u32 max_nr_entries, u32 *nr_entries)

int __init e820__update_table(struct e820_table *table)

{

{

	static struct change_member change_point_list[2*E820_MAX_ENTRIES] __initdata;

	struct e820_entry *entries = table->entries;

	static struct change_member *change_point[2*E820_MAX_ENTRIES] __initdata;

	u32 max_nr_entries = ARRAY_SIZE(table->entries);

	static struct e820_entry *overlap_list[E820_MAX_ENTRIES] __initdata;

	static struct e820_entry new_entries[E820_MAX_ENTRIES] __initdata;

	enum e820_type current_type, last_type;

	enum e820_type current_type, last_type;

	unsigned long long last_addr;

	unsigned long long last_addr;

	u32 chgidx;

	u32 new_nr_entries, overlap_entries;

	u32 overlap_entries;

	u32 i, chg_idx, chg_nr;

	u32 new_nr_entries;

	u32 old_nr, new_nr, chg_nr;

	u32 i;





	/* If there's only one memory region, don't bother: */

	/* If there's only one memory region, don't bother: */

	if (*nr_entries < 2)

	if (table->nr_entries < 2)

		return -1;

		return -1;





	old_nr = *nr_entries;

	table->nr_entries = table->nr_entries;

	BUG_ON(old_nr > max_nr_entries);

	BUG_ON(table->nr_entries > max_nr_entries);





	/* Bail out if we find any unreasonable addresses in the map: */

	/* Bail out if we find any unreasonable addresses in the map: */

	for (i = 0; i < old_nr; i++) {

	for (i = 0; i < table->nr_entries; i++) {

		if (entries[i].addr + entries[i].size < entries[i].addr)

		if (entries[i].addr + entries[i].size < entries[i].addr)

			return -1;

			return -1;

	}

	}





	/* Create pointers for initial change-point information (for sorting): */

	/* Create pointers for initial change-point information (for sorting): */

	for (i = 0; i < 2 * old_nr; i++)

	for (i = 0; i < 2 * table->nr_entries; i++)

		change_point[i] = &change_point_list[i];

		change_point[i] = &change_point_list[i];





	/*

	/*

	 * Record all known change-points (starting and ending addresses),

	 * Record all known change-points (starting and ending addresses),

	 * omitting empty memory regions:

	 * omitting empty memory regions:

	 */

	 */

	chgidx = 0;

	chg_idx = 0;

	for (i = 0; i < old_nr; i++)	{

	for (i = 0; i < table->nr_entries; i++)	{

		if (entries[i].size != 0) {

		if (entries[i].size != 0) {

			change_point[chgidx]->addr	= entries[i].addr;

			change_point[chg_idx]->addr	= entries[i].addr;

			change_point[chgidx++]->entry	= &entries[i];

			change_point[chg_idx++]->entry	= &entries[i];

			change_point[chgidx]->addr	= entries[i].addr + entries[i].size;

			change_point[chg_idx]->addr	= entries[i].addr + entries[i].size;

			change_point[chgidx++]->entry	= &entries[i];

			change_point[chg_idx++]->entry	= &entries[i];

		}

		}

	}

	}

	chg_nr = chgidx;

	chg_nr = chg_idx;





	/* Sort change-point list by memory addresses (low -> high): */

	/* Sort change-point list by memory addresses (low -> high): */

	sort(change_point, chg_nr, sizeof(*change_point), cpcompare, NULL);

	sort(change_point, chg_nr, sizeof(*change_point), cpcompare, NULL);
@@ -308,15 +308,15 @@ static int __init __e820__update_table(struct e820_entry *entries, u32 max_nr_en 
	last_addr = 0;		 /* Start with 0 as last starting address */

	last_addr = 0;		 /* Start with 0 as last starting address */





	/* Loop through change-points, determining effect on the new map: */

	/* Loop through change-points, determining effect on the new map: */

	for (chgidx = 0; chgidx < chg_nr; chgidx++) {

	for (chg_idx = 0; chg_idx < chg_nr; chg_idx++) {

		/* Keep track of all overlapping entries */

		/* Keep track of all overlapping entries */

		if (change_point[chgidx]->addr == change_point[chgidx]->entry->addr) {

		if (change_point[chg_idx]->addr == change_point[chg_idx]->entry->addr) {

			/* Add map entry to overlap list (> 1 entry implies an overlap) */

			/* Add map entry to overlap list (> 1 entry implies an overlap) */

			overlap_list[overlap_entries++] = change_point[chgidx]->entry;

			overlap_list[overlap_entries++] = change_point[chg_idx]->entry;

		} else {

		} else {

			/* Remove entry from list (order independent, so swap with last): */

			/* Remove entry from list (order independent, so swap with last): */

			for (i = 0; i < overlap_entries; i++) {

			for (i = 0; i < overlap_entries; i++) {

				if (overlap_list[i] == change_point[chgidx]->entry)

				if (overlap_list[i] == change_point[chg_idx]->entry)

					overlap_list[i] = overlap_list[overlap_entries-1];

					overlap_list[i] = overlap_list[overlap_entries-1];

			}

			}

			overlap_entries--;

			overlap_entries--;
@@ -335,7 +335,7 @@ static int __init __e820__update_table(struct e820_entry *entries, u32 max_nr_en 
		/* Continue building up new map based on this information: */

		/* Continue building up new map based on this information: */

		if (current_type != last_type || current_type == E820_TYPE_PRAM) {

		if (current_type != last_type || current_type == E820_TYPE_PRAM) {

			if (last_type != 0)	 {

			if (last_type != 0)	 {

				new_entries[new_nr_entries].size = change_point[chgidx]->addr - last_addr;

				new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr;

				/* Move forward only if the new size was non-zero: */

				/* Move forward only if the new size was non-zero: */

				if (new_entries[new_nr_entries].size != 0)

				if (new_entries[new_nr_entries].size != 0)

					/* No more space left for new entries? */

					/* No more space left for new entries? */
@@ -343,29 +343,21 @@ static int __init __e820__update_table(struct e820_entry *entries, u32 max_nr_en 
						break;

						break;

			}

			}

			if (current_type != 0)	{

			if (current_type != 0)	{

				new_entries[new_nr_entries].addr = change_point[chgidx]->addr;

				new_entries[new_nr_entries].addr = change_point[chg_idx]->addr;

				new_entries[new_nr_entries].type = current_type;

				new_entries[new_nr_entries].type = current_type;

				last_addr = change_point[chgidx]->addr;

				last_addr = change_point[chg_idx]->addr;

			}

			}

			last_type = current_type;

			last_type = current_type;

		}

		}

	}

	}





	/* Retain count for the new entries: */

	new_nr = new_nr_entries;



	/* Copy the new entries into the original location: */

	/* Copy the new entries into the original location: */

	memcpy(entries, new_entries, new_nr*sizeof(*entries));

	memcpy(entries, new_entries, new_nr_entries*sizeof(*entries));

	*nr_entries = new_nr;

	table->nr_entries = new_nr_entries;





	return 0;

	return 0;

}

}





int __init e820__update_table(struct e820_table *table)

{

	return __e820__update_table(table->entries, ARRAY_SIZE(table->entries), &table->nr_entries);

}



static int __init __append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)

static int __init __append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)

{

{

	struct boot_e820_entry *entry = entries;

	struct boot_e820_entry *entry = entries;

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