diff mbox series

ACPI: NFIT: Optimize nfit_mem_cmp() for efficiency

Message ID 20231012215903.2104652-1-visitorckw@gmail.com (mailing list archive)
State Handled Elsewhere, archived
Headers show
Series ACPI: NFIT: Optimize nfit_mem_cmp() for efficiency | expand

Commit Message

Kuan-Wei Chiu Oct. 12, 2023, 9:59 p.m. UTC
The original code used conditional branching in the nfit_mem_cmp
function to compare two values and return -1, 1, or 0 based on the
result. However, the list_sort comparison function only needs results
<0, >0, or =0. This patch optimizes the code to make the comparison
branchless, improving efficiency and reducing code size. This change
reduces the number of comparison operations from 1-2 to a single
subtraction operation, thereby saving the number of instructions.

Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
---
 drivers/acpi/nfit/core.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index f96bf32cd368..eea827d9af08 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -1138,11 +1138,7 @@  static int nfit_mem_cmp(void *priv, const struct list_head *_a,
 
 	handleA = __to_nfit_memdev(a)->device_handle;
 	handleB = __to_nfit_memdev(b)->device_handle;
-	if (handleA < handleB)
-		return -1;
-	else if (handleA > handleB)
-		return 1;
-	return 0;
+	return handleA - handleB;
 }
 
 static int nfit_mem_init(struct acpi_nfit_desc *acpi_desc)