Change in coreboot[master]: cpu/x86/sipi_vector: Simplify loop getting unique CPU number

[Patrick Rudolph (Code Review)]

Patrick Rudolph has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/47714 )

Change subject: cpu/x86/sipi_vector: Simplify loop getting unique CPU number
......................................................................

cpu/x86/sipi_vector: Simplify loop getting unique CPU number

Get rid of using eax and reload counter on race condition.

Change-Id: Ie4b9957d8aa1f272ff1db5caf2c69d1e1f086a03
Signed-off-by: Patrick Rudolph 
---
M src/cpu/x86/sipi_vector.S
1 file changed, 2 insertions(+), 3 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/14/47714/1

diff --git a/src/cpu/x86/sipi_vector.S b/src/cpu/x86/sipi_vector.S
index 394c03a..199a12b 100644
--- a/src/cpu/x86/sipi_vector.S
+++ b/src/cpu/x86/sipi_vector.S
@@ -89,10 +89,9 @@
    mov	idt_ptr, %ebx
    lidt	(%ebx)

-	/* Obtain CPU number. */
-	movl	ap_count, %eax
 1:
-	movl	%eax, %ecx
+	/* Obtain CPU number. */
+	movl	ap_count, %ecx
    inc	%ecx
    lock cmpxchg %ecx, ap_count
    jnz	1b

[Christian Walter (Code Review)]

Christian Walter has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/47714 )

Change subject: cpu/x86/sipi_vector: Simplify loop getting unique CPU number
......................................................................

Patch Set 1: Code-Review+2

[Angel Pons (Code Review)]

Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/47714 )

Change subject: cpu/x86/sipi_vector: Simplify loop getting unique CPU number
......................................................................

Patch Set 1: Code-Review+1

[Arthur Heymans (Code Review)]

Attention is currently required from: Patrick Rudolph.
Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/47714 )

Change subject: cpu/x86/sipi_vector: Simplify loop getting unique CPU number
......................................................................

Patch Set 2: Code-Review+2

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/47714 )

Change subject: cpu/x86/sipi_vector: Simplify loop getting unique CPU number
......................................................................

cpu/x86/sipi_vector: Simplify loop getting unique CPU number

Get rid of using eax and reload counter on race condition.

Change-Id: Ie4b9957d8aa1f272ff1db5caf2c69d1e1f086a03
Signed-off-by: Patrick Rudolph 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47714
Reviewed-by: Arthur Heymans 
Reviewed-by: Christian Walter 
Reviewed-by: Angel Pons 
Tested-by: build bot (Jenkins) 
---
M src/cpu/x86/sipi_vector.S
1 file changed, 2 insertions(+), 3 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Arthur Heymans: Looks good to me, approved
  Angel Pons: Looks good to me, but someone else must approve
  Christian Walter: Looks good to me, approved

diff --git a/src/cpu/x86/sipi_vector.S b/src/cpu/x86/sipi_vector.S
index 61d9e34..02ad0d3 100644
--- a/src/cpu/x86/sipi_vector.S
+++ b/src/cpu/x86/sipi_vector.S
@@ -84,10 +84,9 @@
    mov	idt_ptr, %ebx
    lidt	(%ebx)

-	/* Obtain CPU number. */
-	movl	ap_count, %eax
 1:
-	movl	%eax, %ecx
+	/* Obtain CPU number. */
+	movl	ap_count, %ecx
    inc	%ecx
    lock cmpxchg %ecx, ap_count
    jnz	1b