[patch 29/58] x86/ioapic/32: Decrapify phys_id_present_map operation

From: Thomas Gleixner
Date: Mon Jul 17 2023 - 19:18:24 EST


The operation to set the IOAPIC ID in phys_id_present_map is as convoluted
as it can be.

1) Allocate a bitmap of 32byte size on the stack
2) Zero the bitmap and set the IOAPIC ID bit
3) Or the temporary bitmap over phys_id_present_map

The same functionality can be achieved by setting the IOAPIC ID bit
directly in the phys_id_present_map.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/kernel/apic/io_apic.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1511,12 +1511,9 @@ void __init setup_ioapic_ids_from_mpc_no
physid_set(i, phys_id_present_map);
ioapics[ioapic_idx].mp_config.apicid = i;
} else {
- physid_mask_t tmp;
-
- physid_set_mask_of_physid(mpc_ioapic_id(ioapic_idx), &tmp);
apic_printk(APIC_VERBOSE, "Setting %d in the phys_id_present_map\n",
mpc_ioapic_id(ioapic_idx));
- physids_or(phys_id_present_map, phys_id_present_map, tmp);
+ physid_set(mpc_ioapic_id(ioapic_idx), phys_id_present_map);
}

/*