x86_32: apic/summit_32, fix cpu_mask_to_apicid

Perform same-cluster checking even for masks with all (nr_cpu_ids)
bits set and report correct apicid on success instead.

While at it, convert it to for_each_cpu and newer cpumask api.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 21 deletions

diff --git a/arch/x86/kernel/apic/summit_32.c b/arch/x86/kernel/apic/summit_32.c
index 0a1135c5a6de..beda620bee86 100644
--- a/arch/x86/kernel/apic/summit_32.c
+++ b/arch/x86/kernel/apic/summit_32.c
@@ -291,33 +291,21 @@ static int summit_check_phys_apicid_present(int boot_cpu_physical_apicid)
 
 static unsigned int summit_cpu_mask_to_apicid(const cpumask_t *cpumask)
 {
-        int cpus_found = 0;
-        int num_bits_set;
-        int apicid;
-        int cpu;
+        unsigned int round = 0;
+        int cpu, apicid = 0;
 
-        num_bits_set = cpus_weight(*cpumask);
-        if (num_bits_set >= nr_cpu_ids)
-                return BAD_APICID;
         /*
          * The cpus in the mask must all be on the apic cluster.
          */
-        cpu = first_cpu(*cpumask);
-        apicid = summit_cpu_to_logical_apicid(cpu);
-
-        while (cpus_found < num_bits_set) {
-                if (cpu_isset(cpu, *cpumask)) {
-                        int new_apicid = summit_cpu_to_logical_apicid(cpu);
+        for_each_cpu(cpu, cpumask) {
+                int new_apicid = summit_cpu_to_logical_apicid(cpu);
 
-                        if (APIC_CLUSTER(apicid) != APIC_CLUSTER(new_apicid)) {
-                                printk("%s: Not a valid mask!\n", __func__);
-
-                                return BAD_APICID;
-                        }
-                        apicid = apicid | new_apicid;
-                        cpus_found++;
+                if (round && APIC_CLUSTER(apicid) != APIC_CLUSTER(new_apicid)) {
+                        printk("%s: Not a valid mask!\n", __func__);
+                        return BAD_APICID;
                 }
-                cpu++;
+                apicid |= new_apicid;
+                round++;
         }
         return apicid;
 }