1 files changed, 261 insertions, 33 deletions

diff --git a/arch/ia64/kernel/smpboot.c b/arch/ia64/kernel/smpboot.c
index 5318f0cbfc26..0d5ee57c9865 100644
--- a/arch/ia64/kernel/smpboot.c
+++ b/arch/ia64/kernel/smpboot.c
@@ -1,14 +1,25 @@
 /*
  * SMP boot-related support
  *
- * Copyright (C) 1998-2003 Hewlett-Packard Co
+ * Copyright (C) 1998-2003, 2005 Hewlett-Packard Co
  *      David Mosberger-Tang <davidm@hpl.hp.com>
+ * Copyright (C) 2001, 2004-2005 Intel Corp
+ *      Rohit Seth <rohit.seth@intel.com>
+ *      Suresh Siddha <suresh.b.siddha@intel.com>
+ *      Gordon Jin <gordon.jin@intel.com>
+ *      Ashok Raj  <ashok.raj@intel.com>
  *
  * 01/05/16 Rohit Seth <rohit.seth@intel.com>   Moved SMP booting functions from smp.c to here.
  * 01/04/27 David Mosberger <davidm@hpl.hp.com> Added ITC synching code.
  * 02/07/31 David Mosberger <davidm@hpl.hp.com> Switch over to hotplug-CPU boot-sequence.
  *                                              smp_boot_cpus()/smp_commence() is replaced by
  *                                              smp_prepare_cpus()/__cpu_up()/smp_cpus_done().
+ * 04/06/21 Ashok Raj           <ashok.raj@intel.com> Added CPU Hotplug Support
+ * 04/12/26 Jin Gordon <gordon.jin@intel.com>
+ * 04/12/26 Rohit Seth <rohit.seth@intel.com>
+ *                                              Add multi-threading and multi-core detection
+ * 05/01/30 Suresh Siddha <suresh.b.siddha@intel.com>
+ *                                              Setup cpu_sibling_map and cpu_core_map
  */
 #include <linux/config.h>
 
@@ -58,6 +69,37 @@
 #define Dprintk(x...)
 #endif
 
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * Store all idle threads, this can be reused instead of creating
+ * a new thread. Also avoids complicated thread destroy functionality
+ * for idle threads.
+ */
+struct task_struct *idle_thread_array[NR_CPUS];
+
+/*
+ * Global array allocated for NR_CPUS at boot time
+ */
+struct sal_to_os_boot sal_boot_rendez_state[NR_CPUS];
+
+/*
+ * start_ap in head.S uses this to store current booting cpu
+ * info.
+ */
+struct sal_to_os_boot *sal_state_for_booting_cpu = &sal_boot_rendez_state[0];
+
+#define set_brendez_area(x) (sal_state_for_booting_cpu = &sal_boot_rendez_state[(x)]);
+
+#define get_idle_for_cpu(x)             (idle_thread_array[(x)])
+#define set_idle_for_cpu(x,p)   (idle_thread_array[(x)] = (p))
+
+#else
+
+#define get_idle_for_cpu(x)             (NULL)
+#define set_idle_for_cpu(x,p)
+#define set_brendez_area(x)
+#endif
+
 
 /*
  * ITC synchronization related stuff:
@@ -90,6 +132,11 @@ EXPORT_SYMBOL(cpu_online_map);
 cpumask_t cpu_possible_map;
 EXPORT_SYMBOL(cpu_possible_map);
 
+cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
+cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned;
+int smp_num_siblings = 1;
+int smp_num_cpucores = 1;
+
 /* which logical CPU number maps to which CPU (physical APIC ID) */
 volatile int ia64_cpu_to_sapicid[NR_CPUS];
 EXPORT_SYMBOL(ia64_cpu_to_sapicid);
@@ -124,7 +171,8 @@ sync_master (void *arg)
         local_irq_save(flags);
         {
                 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; ++i) {
-                        while (!go[MASTER]);
+                        while (!go[MASTER])
+                                cpu_relax();
                         go[MASTER] = 0;
                         go[SLAVE] = ia64_get_itc();
                 }
@@ -147,7 +195,8 @@ get_delta (long *rt, long *master)
         for (i = 0; i < NUM_ITERS; ++i) {
                 t0 = ia64_get_itc();
                 go[MASTER] = 1;
-                while (!(tm = go[SLAVE]));
+                while (!(tm = go[SLAVE]))
+                        cpu_relax();
                 go[SLAVE] = 0;
                 t1 = ia64_get_itc();
 
@@ -226,7 +275,8 @@ ia64_sync_itc (unsigned int master)
                 return;
         }
 
-        while (go[MASTER]);     /* wait for master to be ready */
+        while (go[MASTER])
+                cpu_relax();    /* wait for master to be ready */
 
         spin_lock_irqsave(&itc_sync_lock, flags);
         {
@@ -345,7 +395,6 @@ start_secondary (void *unused)
 {
         /* Early console may use I/O ports */
         ia64_set_kr(IA64_KR_IO_BASE, __pa(ia64_iobase));
-
         Dprintk("start_secondary: starting CPU 0x%x\n", hard_smp_processor_id());
         efi_map_pal_code();
         cpu_init();
@@ -384,6 +433,13 @@ do_boot_cpu (int sapicid, int cpu)
                 .done   = COMPLETION_INITIALIZER(c_idle.done),
         };
         DECLARE_WORK(work, do_fork_idle, &c_idle);
+
+        c_idle.idle = get_idle_for_cpu(cpu);
+        if (c_idle.idle) {
+                init_idle(c_idle.idle, cpu);
+                goto do_rest;
+        }
+
         /*
          * We can't use kernel_thread since we must avoid to reschedule the child.
          */
@@ -396,10 +452,15 @@ do_boot_cpu (int sapicid, int cpu)
 
         if (IS_ERR(c_idle.idle))
                 panic("failed fork for CPU %d", cpu);
+
+        set_idle_for_cpu(cpu, c_idle.idle);
+
+do_rest:
         task_for_booting_cpu = c_idle.idle;
 
         Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);
 
+        set_brendez_area(cpu);
         platform_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);
 
         /*
@@ -552,19 +613,70 @@ void __devinit smp_prepare_boot_cpu(void)
         cpu_set(smp_processor_id(), cpu_callin_map);
 }
 
+/*
+ * mt_info[] is a temporary store for all info returned by
+ * PAL_LOGICAL_TO_PHYSICAL, to be copied into cpuinfo_ia64 when the
+ * specific cpu comes.
+ */
+static struct {
+        __u32   socket_id;
+        __u16   core_id;
+        __u16   thread_id;
+        __u16   proc_fixed_addr;
+        __u8    valid;
+}mt_info[NR_CPUS] __devinit;
+
 #ifdef CONFIG_HOTPLUG_CPU
-extern void fixup_irqs(void);
-/* must be called with cpucontrol mutex held */
-static int __devinit cpu_enable(unsigned int cpu)
+static inline void
+remove_from_mtinfo(int cpu)
 {
-        per_cpu(cpu_state,cpu) = CPU_UP_PREPARE;
-        wmb();
+        int i;
 
-        while (!cpu_online(cpu))
-                cpu_relax();
-        return 0;
+        for_each_cpu(i)
+                if (mt_info[i].valid &&  mt_info[i].socket_id ==
+                                                cpu_data(cpu)->socket_id)
+                        mt_info[i].valid = 0;
+}
+
+static inline void
+clear_cpu_sibling_map(int cpu)
+{
+        int i;
+
+        for_each_cpu_mask(i, cpu_sibling_map[cpu])
+                cpu_clear(cpu, cpu_sibling_map[i]);
+        for_each_cpu_mask(i, cpu_core_map[cpu])
+                cpu_clear(cpu, cpu_core_map[i]);
+
+        cpu_sibling_map[cpu] = cpu_core_map[cpu] = CPU_MASK_NONE;
+}
+
+static void
+remove_siblinginfo(int cpu)
+{
+        int last = 0;
+
+        if (cpu_data(cpu)->threads_per_core == 1 &&
+            cpu_data(cpu)->cores_per_socket == 1) {
+                cpu_clear(cpu, cpu_core_map[cpu]);
+                cpu_clear(cpu, cpu_sibling_map[cpu]);
+                return;
+        }
+
+        last = (cpus_weight(cpu_core_map[cpu]) == 1 ? 1 : 0);
+
+        /* remove it from all sibling map's */
+        clear_cpu_sibling_map(cpu);
+
+        /* if this cpu is the last in the core group, remove all its info 
+         * from mt_info structure
+         */
+        if (last)
+                remove_from_mtinfo(cpu);
 }
 
+extern void fixup_irqs(void);
+/* must be called with cpucontrol mutex held */
 int __cpu_disable(void)
 {
         int cpu = smp_processor_id();
@@ -575,9 +687,10 @@ int __cpu_disable(void)
         if (cpu == 0)
                 return -EBUSY;
 
+        remove_siblinginfo(cpu);
         fixup_irqs();
         local_flush_tlb_all();
-        printk ("Disabled cpu %u\n", smp_processor_id());
+        cpu_clear(cpu, cpu_callin_map);
         return 0;
 }
 
@@ -589,12 +702,7 @@ void __cpu_die(unsigned int cpu)
                 /* They ack this in play_dead by setting CPU_DEAD */
                 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
                 {
-                        /*
-                         * TBD: Enable this when physical removal
-                         * or when we put the processor is put in
-                         * SAL_BOOT_RENDEZ mode
-                         * cpu_clear(cpu, cpu_callin_map);
-                         */
+                        printk ("CPU %d is now offline\n", cpu);
                         return;
                 }
                 msleep(100);
@@ -602,11 +710,6 @@ void __cpu_die(unsigned int cpu)
         printk(KERN_ERR "CPU %u didn't die...\n", cpu);
 }
 #else /* !CONFIG_HOTPLUG_CPU */
-static int __devinit cpu_enable(unsigned int cpu)
-{
-        return 0;
-}
-
 int __cpu_disable(void)
 {
         return -ENOSYS;
@@ -637,6 +740,23 @@ smp_cpus_done (unsigned int dummy)
                (int)num_online_cpus(), bogosum/(500000/HZ), (bogosum/(5000/HZ))%100);
 }
 
+static inline void __devinit
+set_cpu_sibling_map(int cpu)
+{
+        int i;
+
+        for_each_online_cpu(i) {
+                if ((cpu_data(cpu)->socket_id == cpu_data(i)->socket_id)) {
+                        cpu_set(i, cpu_core_map[cpu]);
+                        cpu_set(cpu, cpu_core_map[i]);
+                        if (cpu_data(cpu)->core_id == cpu_data(i)->core_id) {
+                                cpu_set(i, cpu_sibling_map[cpu]);
+                                cpu_set(cpu, cpu_sibling_map[i]);
+                        }
+                }
+        }
+}
+
 int __devinit
 __cpu_up (unsigned int cpu)
 {
@@ -648,21 +768,26 @@ __cpu_up (unsigned int cpu)
                 return -EINVAL;
 
         /*
-         * Already booted.. just enable and get outa idle lool
+         * Already booted cpu? not valid anymore since we dont
+         * do idle loop tightspin anymore.
          */
         if (cpu_isset(cpu, cpu_callin_map))
-        {
-                cpu_enable(cpu);
-                local_irq_enable();
-                while (!cpu_isset(cpu, cpu_online_map))
-                        mb();
-                return 0;
-        }
+                return -EINVAL;
+
         /* Processor goes to start_secondary(), sets online flag */
         ret = do_boot_cpu(sapicid, cpu);
         if (ret < 0)
                 return ret;
 
+        if (cpu_data(cpu)->threads_per_core == 1 &&
+            cpu_data(cpu)->cores_per_socket == 1) {
+                cpu_set(cpu, cpu_sibling_map[cpu]);
+                cpu_set(cpu, cpu_core_map[cpu]);
+                return 0;
+        }
+
+        set_cpu_sibling_map(cpu);
+
         return 0;
 }
 
@@ -690,3 +815,106 @@ init_smp_config(void)
                        ia64_sal_strerror(sal_ret));
 }
 
+static inline int __devinit
+check_for_mtinfo_index(void)
+{
+        int i;
+        
+        for_each_cpu(i)
+                if (!mt_info[i].valid)
+                        return i;
+
+        return -1;
+}
+
+/*
+ * Search the mt_info to find out if this socket's cid/tid information is
+ * cached or not. If the socket exists, fill in the core_id and thread_id 
+ * in cpuinfo
+ */
+static int __devinit
+check_for_new_socket(__u16 logical_address, struct cpuinfo_ia64 *c)
+{
+        int i;
+        __u32 sid = c->socket_id;
+
+        for_each_cpu(i) {
+                if (mt_info[i].valid && mt_info[i].proc_fixed_addr == logical_address
+                    && mt_info[i].socket_id == sid) {
+                        c->core_id = mt_info[i].core_id;
+                        c->thread_id = mt_info[i].thread_id;
+                        return 1; /* not a new socket */
+                }
+        }
+        return 0;
+}
+
+/*
+ * identify_siblings(cpu) gets called from identify_cpu. This populates the 
+ * information related to logical execution units in per_cpu_data structure.
+ */
+void __devinit
+identify_siblings(struct cpuinfo_ia64 *c)
+{
+        s64 status;
+        u16 pltid;
+        u64 proc_fixed_addr;
+        int count, i;
+        pal_logical_to_physical_t info;
+
+        if (smp_num_cpucores == 1 && smp_num_siblings == 1)
+                return;
+
+        if ((status = ia64_pal_logical_to_phys(0, &info)) != PAL_STATUS_SUCCESS) {
+                printk(KERN_ERR "ia64_pal_logical_to_phys failed with %ld\n",
+                       status);
+                return;
+        }
+        if ((status = ia64_sal_physical_id_info(&pltid)) != PAL_STATUS_SUCCESS) {
+                printk(KERN_ERR "ia64_sal_pltid failed with %ld\n", status);
+                return;
+        }
+        if ((status = ia64_pal_fixed_addr(&proc_fixed_addr)) != PAL_STATUS_SUCCESS) {
+                printk(KERN_ERR "ia64_pal_fixed_addr failed with %ld\n", status);
+                return;
+        }
+
+        c->socket_id =  (pltid << 8) | info.overview_ppid;
+        c->cores_per_socket = info.overview_cpp;
+        c->threads_per_core = info.overview_tpc;
+        count = c->num_log = info.overview_num_log;
+
+        /* If the thread and core id information is already cached, then
+         * we will simply update cpu_info and return. Otherwise, we will
+         * do the PAL calls and cache core and thread id's of all the siblings.
+         */
+        if (check_for_new_socket(proc_fixed_addr, c))
+                return;
+
+        for (i = 0; i < count; i++) {
+                int index;
+
+                if (i && (status = ia64_pal_logical_to_phys(i, &info))
+                          != PAL_STATUS_SUCCESS) {
+                        printk(KERN_ERR "ia64_pal_logical_to_phys failed"
+                                        " with %ld\n", status);
+                        return;
+                }
+                if (info.log2_la == proc_fixed_addr) {
+                        c->core_id = info.log1_cid;
+                        c->thread_id = info.log1_tid;
+                }
+
+                index = check_for_mtinfo_index();
+                /* We will not do the mt_info caching optimization in this case.
+                 */
+                if (index < 0)
+                        continue;
+
+                mt_info[index].valid = 1;
+                mt_info[index].socket_id = c->socket_id;
+                mt_info[index].core_id = info.log1_cid;
+                mt_info[index].thread_id = info.log1_tid;
+                mt_info[index].proc_fixed_addr = info.log2_la;
+        }
+}