[PATCH 1/2] x86/boot/e820: not necessary to iterate whole overlap_list

[PATCH 1/2] x86/boot/e820: not necessary to iterate whole overlap_list

[Wei Yang]

We are sure there is only one entry to be removed from overlap_list.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
 arch/x86/kernel/e820.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 6f1b379e3b38..ecbeb76ed08f 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -377,10 +377,11 @@ int __init e820__update_table(struct e820_table *table)
 		} else {
 			/* Remove entry from list (order independent, so swap with last): */
 			for (i = 0; i < overlap_entries; i++) {
-				if (overlap_list[i] == change_point[chg_idx]->entry)
-					overlap_list[i] = overlap_list[overlap_entries-1];
+				if (overlap_list[i] == change_point[chg_idx]->entry) {
+					overlap_list[i] = overlap_list[--overlap_entries];
+					break;
+				}
 			}
-			overlap_entries--;
 		}
 		/*
 		 * If there are overlapping entries, decide which
-- 
2.34.1

[PATCH 2/2] x86/boot/e820: a local variable for last_addr is not necessary

[Wei Yang]

We only use this to calculate the size of new entry as the start
address, which is already stored in new_entries->addr.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
 arch/x86/kernel/e820.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index ecbeb76ed08f..8d431ac3f76e 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -324,7 +324,6 @@ int __init e820__update_table(struct e820_table *table)
 	struct e820_entry *entries = table->entries;
 	u32 max_nr_entries = ARRAY_SIZE(table->entries);
 	enum e820_type current_type, last_type;
-	unsigned long long last_addr;
 	u32 new_nr_entries, overlap_entries;
 	u32 i, chg_idx, chg_nr;
 
@@ -366,7 +365,6 @@ int __init e820__update_table(struct e820_table *table)
 	overlap_entries = 0;	 /* Number of entries in the overlap table */
 	new_nr_entries = 0;	 /* Index for creating new map entries */
 	last_type = 0;		 /* Start with undefined memory type */
-	last_addr = 0;		 /* Start with 0 as last starting address */
 
 	/* Loop through change-points, determining effect on the new map: */
 	for (chg_idx = 0; chg_idx < chg_nr; chg_idx++) {
@@ -397,7 +395,8 @@ int __init e820__update_table(struct e820_table *table)
 		/* Continue building up new map based on this information: */
 		if (current_type != last_type || e820_nomerge(current_type)) {
 			if (last_type) {
-				new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr;
+				new_entries[new_nr_entries].size =
+					change_point[chg_idx]->addr - new_entries[new_nr_entries].addr;
 				/* Move forward only if the new size was non-zero: */
 				if (new_entries[new_nr_entries].size != 0)
 					/* No more space left for new entries? */
@@ -407,7 +406,6 @@ int __init e820__update_table(struct e820_table *table)
 			if (current_type) {
 				new_entries[new_nr_entries].addr = change_point[chg_idx]->addr;
 				new_entries[new_nr_entries].type = current_type;
-				last_addr = change_point[chg_idx]->addr;
 			}
 			last_type = current_type;
 		}
-- 
2.34.1