]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - arch/ia64/mm/tlb.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
[linux-2.6-omap-h63xx.git] / arch / ia64 / mm / tlb.c
index cef164729db79d77d5b3cb8c694787cf10b8cc6f..bd9818a36b4769e9aa961ea82206bdfb8ff21fb9 100644 (file)
  *              IPI based ptc implementation and A-step IPI implementation.
  * Rohit Seth <rohit.seth@intel.com>
  * Ken Chen <kenneth.w.chen@intel.com>
+ * Christophe de Dinechin <ddd@hp.com>: Avoid ptc.e on memory allocation
+ * Copyright (C) 2007 Intel Corp
+ *     Fenghua Yu <fenghua.yu@intel.com>
+ *     Add multiple ptc.g/ptc.ga instruction support in global tlb purge.
  */
 #include <linux/module.h>
 #include <linux/init.h>
@@ -25,6 +29,9 @@
 #include <asm/pal.h>
 #include <asm/tlbflush.h>
 #include <asm/dma.h>
+#include <asm/processor.h>
+#include <asm/sal.h>
+#include <asm/tlb.h>
 
 static struct {
        unsigned long mask;     /* mask of supported purge page-sizes */
@@ -38,6 +45,10 @@ struct ia64_ctx ia64_ctx = {
 };
 
 DEFINE_PER_CPU(u8, ia64_need_tlb_flush);
+DEFINE_PER_CPU(u8, ia64_tr_num);  /*Number of TR slots in current processor*/
+DEFINE_PER_CPU(u8, ia64_tr_used); /*Max Slot number used by kernel*/
+
+struct ia64_tr_entry __per_cpu_idtrs[NR_CPUS][2][IA64_TR_ALLOC_MAX];
 
 /*
  * Initializes the ia64_ctx.bitmap array based on max_ctx+1.
@@ -83,30 +94,171 @@ wrap_mmu_context (struct mm_struct *mm)
        local_flush_tlb_all();
 }
 
+/*
+ * Implement "spinaphores" ... like counting semaphores, but they
+ * spin instead of sleeping.  If there are ever any other users for
+ * this primitive it can be moved up to a spinaphore.h header.
+ */
+struct spinaphore {
+       atomic_t        cur;
+};
+
+static inline void spinaphore_init(struct spinaphore *ss, int val)
+{
+       atomic_set(&ss->cur, val);
+}
+
+static inline void down_spin(struct spinaphore *ss)
+{
+       while (unlikely(!atomic_add_unless(&ss->cur, -1, 0)))
+               while (atomic_read(&ss->cur) == 0)
+                       cpu_relax();
+}
+
+static inline void up_spin(struct spinaphore *ss)
+{
+       atomic_add(1, &ss->cur);
+}
+
+static struct spinaphore ptcg_sem;
+static u16 nptcg = 1;
+static int need_ptcg_sem = 1;
+static int toolatetochangeptcgsem = 0;
+
+/*
+ * Kernel parameter "nptcg=" overrides max number of concurrent global TLB
+ * purges which is reported from either PAL or SAL PALO.
+ *
+ * We don't have sanity checking for nptcg value. It's the user's responsibility
+ * for valid nptcg value on the platform. Otherwise, kernel may hang in some
+ * cases.
+ */
+static int __init
+set_nptcg(char *str)
+{
+       int value = 0;
+
+       get_option(&str, &value);
+       setup_ptcg_sem(value, NPTCG_FROM_KERNEL_PARAMETER);
+
+       return 1;
+}
+
+__setup("nptcg=", set_nptcg);
+
+/*
+ * Maximum number of simultaneous ptc.g purges in the system can
+ * be defined by PAL_VM_SUMMARY (in which case we should take
+ * the smallest value for any cpu in the system) or by the PAL
+ * override table (in which case we should ignore the value from
+ * PAL_VM_SUMMARY).
+ *
+ * Kernel parameter "nptcg=" overrides maximum number of simultanesous ptc.g
+ * purges defined in either PAL_VM_SUMMARY or PAL override table. In this case,
+ * we should ignore the value from either PAL_VM_SUMMARY or PAL override table.
+ *
+ * Complicating the logic here is the fact that num_possible_cpus()
+ * isn't fully setup until we start bringing cpus online.
+ */
 void
-ia64_global_tlb_purge (struct mm_struct *mm, unsigned long start,
-                      unsigned long end, unsigned long nbits)
+setup_ptcg_sem(int max_purges, int nptcg_from)
 {
-       static DEFINE_SPINLOCK(ptcg_lock);
+       static int kp_override;
+       static int palo_override;
+       static int firstcpu = 1;
 
-       if (mm != current->active_mm || !current->mm) {
-               flush_tlb_all();
+       if (toolatetochangeptcgsem) {
+               if (nptcg_from == NPTCG_FROM_PAL && max_purges == 0)
+                       BUG_ON(1 < nptcg);
+               else
+                       BUG_ON(max_purges < nptcg);
                return;
        }
 
-       /* HW requires global serialization of ptc.ga.  */
-       spin_lock(&ptcg_lock);
-       {
-               do {
-                       /*
-                        * Flush ALAT entries also.
-                        */
-                       ia64_ptcga(start, (nbits<<2));
-                       ia64_srlz_i();
-                       start += (1UL << nbits);
-               } while (start < end);
+       if (nptcg_from == NPTCG_FROM_KERNEL_PARAMETER) {
+               kp_override = 1;
+               nptcg = max_purges;
+               goto resetsema;
+       }
+       if (kp_override) {
+               need_ptcg_sem = num_possible_cpus() > nptcg;
+               return;
+       }
+
+       if (nptcg_from == NPTCG_FROM_PALO) {
+               palo_override = 1;
+
+               /* In PALO max_purges == 0 really means it! */
+               if (max_purges == 0)
+                       panic("Whoa! Platform does not support global TLB purges.\n");
+               nptcg = max_purges;
+               if (nptcg == PALO_MAX_TLB_PURGES) {
+                       need_ptcg_sem = 0;
+                       return;
+               }
+               goto resetsema;
        }
-       spin_unlock(&ptcg_lock);
+       if (palo_override) {
+               if (nptcg != PALO_MAX_TLB_PURGES)
+                       need_ptcg_sem = (num_possible_cpus() > nptcg);
+               return;
+       }
+
+       /* In PAL_VM_SUMMARY max_purges == 0 actually means 1 */
+       if (max_purges == 0) max_purges = 1;
+
+       if (firstcpu) {
+               nptcg = max_purges;
+               firstcpu = 0;
+       }
+       if (max_purges < nptcg)
+               nptcg = max_purges;
+       if (nptcg == PAL_MAX_PURGES) {
+               need_ptcg_sem = 0;
+               return;
+       } else
+               need_ptcg_sem = (num_possible_cpus() > nptcg);
+
+resetsema:
+       spinaphore_init(&ptcg_sem, max_purges);
+}
+
+void
+ia64_global_tlb_purge (struct mm_struct *mm, unsigned long start,
+                      unsigned long end, unsigned long nbits)
+{
+       struct mm_struct *active_mm = current->active_mm;
+
+       toolatetochangeptcgsem = 1;
+
+       if (mm != active_mm) {
+               /* Restore region IDs for mm */
+               if (mm && active_mm) {
+                       activate_context(mm);
+               } else {
+                       flush_tlb_all();
+                       return;
+               }
+       }
+
+       if (need_ptcg_sem)
+               down_spin(&ptcg_sem);
+
+       do {
+               /*
+                * Flush ALAT entries also.
+                */
+               ia64_ptcga(start, (nbits << 2));
+               ia64_srlz_i();
+               start += (1UL << nbits);
+       } while (start < end);
+
+       if (need_ptcg_sem)
+               up_spin(&ptcg_sem);
+
+        if (mm != active_mm) {
+                activate_context(active_mm);
+        }
 }
 
 void
@@ -178,6 +330,9 @@ ia64_tlb_init (void)
        ia64_ptce_info_t uninitialized_var(ptce_info); /* GCC be quiet */
        unsigned long tr_pgbits;
        long status;
+       pal_vm_info_1_u_t vm_info_1;
+       pal_vm_info_2_u_t vm_info_2;
+       int cpu = smp_processor_id();
 
        if ((status = ia64_pal_vm_page_size(&tr_pgbits, &purge.mask)) != 0) {
                printk(KERN_ERR "PAL_VM_PAGE_SIZE failed with status=%ld; "
@@ -194,4 +349,195 @@ ia64_tlb_init (void)
        local_cpu_data->ptce_stride[1] = ptce_info.stride[1];
 
        local_flush_tlb_all();  /* nuke left overs from bootstrapping... */
+       status = ia64_pal_vm_summary(&vm_info_1, &vm_info_2);
+
+       if (status) {
+               printk(KERN_ERR "ia64_pal_vm_summary=%ld\n", status);
+               per_cpu(ia64_tr_num, cpu) = 8;
+               return;
+       }
+       per_cpu(ia64_tr_num, cpu) = vm_info_1.pal_vm_info_1_s.max_itr_entry+1;
+       if (per_cpu(ia64_tr_num, cpu) >
+                               (vm_info_1.pal_vm_info_1_s.max_dtr_entry+1))
+               per_cpu(ia64_tr_num, cpu) =
+                               vm_info_1.pal_vm_info_1_s.max_dtr_entry+1;
+       if (per_cpu(ia64_tr_num, cpu) > IA64_TR_ALLOC_MAX) {
+               static int justonce = 1;
+               per_cpu(ia64_tr_num, cpu) = IA64_TR_ALLOC_MAX;
+               if (justonce) {
+                       justonce = 0;
+                       printk(KERN_DEBUG "TR register number exceeds "
+                              "IA64_TR_ALLOC_MAX!\n");
+               }
+       }
+}
+
+/*
+ * is_tr_overlap
+ *
+ * Check overlap with inserted TRs.
+ */
+static int is_tr_overlap(struct ia64_tr_entry *p, u64 va, u64 log_size)
+{
+       u64 tr_log_size;
+       u64 tr_end;
+       u64 va_rr = ia64_get_rr(va);
+       u64 va_rid = RR_TO_RID(va_rr);
+       u64 va_end = va + (1<<log_size) - 1;
+
+       if (va_rid != RR_TO_RID(p->rr))
+               return 0;
+       tr_log_size = (p->itir & 0xff) >> 2;
+       tr_end = p->ifa + (1<<tr_log_size) - 1;
+
+       if (va > tr_end || p->ifa > va_end)
+               return 0;
+       return 1;
+
+}
+
+/*
+ * ia64_insert_tr in virtual mode. Allocate a TR slot
+ *
+ * target_mask : 0x1 : itr, 0x2 : dtr, 0x3 : idtr
+ *
+ * va  : virtual address.
+ * pte         : pte entries inserted.
+ * log_size: range to be covered.
+ *
+ * Return value:  <0 :  error No.
+ *
+ *               >=0 : slot number allocated for TR.
+ * Must be called with preemption disabled.
+ */
+int ia64_itr_entry(u64 target_mask, u64 va, u64 pte, u64 log_size)
+{
+       int i, r;
+       unsigned long psr;
+       struct ia64_tr_entry *p;
+       int cpu = smp_processor_id();
+
+       r = -EINVAL;
+       /*Check overlap with existing TR entries*/
+       if (target_mask & 0x1) {
+               p = &__per_cpu_idtrs[cpu][0][0];
+               for (i = IA64_TR_ALLOC_BASE; i <= per_cpu(ia64_tr_used, cpu);
+                                                               i++, p++) {
+                       if (p->pte & 0x1)
+                               if (is_tr_overlap(p, va, log_size)) {
+                                       printk(KERN_DEBUG "Overlapped Entry"
+                                               "Inserted for TR Reigster!!\n");
+                                       goto out;
+                       }
+               }
+       }
+       if (target_mask & 0x2) {
+               p = &__per_cpu_idtrs[cpu][1][0];
+               for (i = IA64_TR_ALLOC_BASE; i <= per_cpu(ia64_tr_used, cpu);
+                                                               i++, p++) {
+                       if (p->pte & 0x1)
+                               if (is_tr_overlap(p, va, log_size)) {
+                                       printk(KERN_DEBUG "Overlapped Entry"
+                                               "Inserted for TR Reigster!!\n");
+                                       goto out;
+                               }
+               }
+       }
+
+       for (i = IA64_TR_ALLOC_BASE; i < per_cpu(ia64_tr_num, cpu); i++) {
+               switch (target_mask & 0x3) {
+               case 1:
+                       if (!(__per_cpu_idtrs[cpu][0][i].pte & 0x1))
+                               goto found;
+                       continue;
+               case 2:
+                       if (!(__per_cpu_idtrs[cpu][1][i].pte & 0x1))
+                               goto found;
+                       continue;
+               case 3:
+                       if (!(__per_cpu_idtrs[cpu][0][i].pte & 0x1) &&
+                               !(__per_cpu_idtrs[cpu][1][i].pte & 0x1))
+                               goto found;
+                       continue;
+               default:
+                       r = -EINVAL;
+                       goto out;
+               }
+       }
+found:
+       if (i >= per_cpu(ia64_tr_num, cpu))
+               return -EBUSY;
+
+       /*Record tr info for mca hander use!*/
+       if (i > per_cpu(ia64_tr_used, cpu))
+               per_cpu(ia64_tr_used, cpu) = i;
+
+       psr = ia64_clear_ic();
+       if (target_mask & 0x1) {
+               ia64_itr(0x1, i, va, pte, log_size);
+               ia64_srlz_i();
+               p = &__per_cpu_idtrs[cpu][0][i];
+               p->ifa = va;
+               p->pte = pte;
+               p->itir = log_size << 2;
+               p->rr = ia64_get_rr(va);
+       }
+       if (target_mask & 0x2) {
+               ia64_itr(0x2, i, va, pte, log_size);
+               ia64_srlz_i();
+               p = &__per_cpu_idtrs[cpu][1][i];
+               p->ifa = va;
+               p->pte = pte;
+               p->itir = log_size << 2;
+               p->rr = ia64_get_rr(va);
+       }
+       ia64_set_psr(psr);
+       r = i;
+out:
+       return r;
+}
+EXPORT_SYMBOL_GPL(ia64_itr_entry);
+
+/*
+ * ia64_purge_tr
+ *
+ * target_mask: 0x1: purge itr, 0x2 : purge dtr, 0x3 purge idtr.
+ * slot: slot number to be freed.
+ *
+ * Must be called with preemption disabled.
+ */
+void ia64_ptr_entry(u64 target_mask, int slot)
+{
+       int cpu = smp_processor_id();
+       int i;
+       struct ia64_tr_entry *p;
+
+       if (slot < IA64_TR_ALLOC_BASE || slot >= per_cpu(ia64_tr_num, cpu))
+               return;
+
+       if (target_mask & 0x1) {
+               p = &__per_cpu_idtrs[cpu][0][slot];
+               if ((p->pte&0x1) && is_tr_overlap(p, p->ifa, p->itir>>2)) {
+                       p->pte = 0;
+                       ia64_ptr(0x1, p->ifa, p->itir>>2);
+                       ia64_srlz_i();
+               }
+       }
+
+       if (target_mask & 0x2) {
+               p = &__per_cpu_idtrs[cpu][1][slot];
+               if ((p->pte & 0x1) && is_tr_overlap(p, p->ifa, p->itir>>2)) {
+                       p->pte = 0;
+                       ia64_ptr(0x2, p->ifa, p->itir>>2);
+                       ia64_srlz_i();
+               }
+       }
+
+       for (i = per_cpu(ia64_tr_used, cpu); i >= IA64_TR_ALLOC_BASE; i--) {
+               if ((__per_cpu_idtrs[cpu][0][i].pte & 0x1) ||
+                               (__per_cpu_idtrs[cpu][1][i].pte & 0x1))
+                       break;
+       }
+       per_cpu(ia64_tr_used, cpu) = i;
 }
+EXPORT_SYMBOL_GPL(ia64_ptr_entry);