x86, AMD IOMMU: remove unneeded initializations from command buffer allocation

This patch removes an unneeded initialization from the alloc_command_buffer
function and replaces a memset with __GFP_ZERO.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 0f5a9115a6947bb3d6d9db776ee6284886e6d855..0124995c7b5d2fb88b8b982927c955c7a2ceb342 100644 (file)
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -394,17 +394,15 @@ static int __init find_last_devid_acpi(struct acpi_table_header *table)
  */
 static u8 * __init alloc_command_buffer(struct amd_iommu *iommu)
 {
-       u8 *cmd_buf = (u8 *)__get_free_pages(GFP_KERNEL,
+       u8 *cmd_buf = (u8 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
                        get_order(CMD_BUFFER_SIZE));
-       u64 entry = 0;
+       u64 entry;
 
        if (cmd_buf == NULL)
                return NULL;
 
        iommu->cmd_buf_size = CMD_BUFFER_SIZE;
 
-       memset(cmd_buf, 0, CMD_BUFFER_SIZE);
-
        entry = (u64)virt_to_phys(cmd_buf);
        entry |= MMIO_CMD_SIZE_512;
        memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET,