Changeset d1e414c in mainline for generic/src/mm/tlb.c

Timestamp:

2006-03-15T00:51:25Z (19 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

91d5ad6

Parents:

51cc6bf6

Message:

More lightweighed TLB shootdown implementation.

File:

• generic/src/mm/tlb.c (modified) (5 diffs)

generic/src/mm/tlb.c

@@ -28 +28 @@
 
 #include <mm/tlb.h>
+#include <mm/asid.h>
 #include <arch/mm/tlb.h>
 #include <smp/ipi.h>
@@ -37 +38 @@
 #include <arch.h>
 #include <panic.h>
+#include <debug.h>
 
+/**
+ * This lock is used for synchronisation between sender and
+ * recipients of TLB shootdown message. It must be acquired
+ * before CPU structure lock.
+ */
 SPINLOCK_INITIALIZE(tlblock);
 
@@ -46 +53 @@
 
 #ifdef CONFIG_SMP
-/* must be called with interrupts disabled */
-void tlb_shootdown_start(tlb_invalidate_type_t type, asid_t asid, __address page, count_t cnt)
+
+/** Send TLB shootdown message.
+ *
+ * This function attempts to deliver TLB shootdown message
+ * to all other processors.
+ *
+ * This function must be called with interrupts disabled.
+ *
+ * @param type Type describing scope of shootdown.
+ * @param asid Address space, if required by type.
+ * @param page Virtual page address, if required by type.
+ * @param count Number of pages, if required by type.
+ */
+void tlb_shootdown_start(tlb_invalidate_type_t type, asid_t asid, __address page, count_t count)
 {
         int i;
@@ -54 +73 @@
         spinlock_lock(&tlblock);
         
-        /*
-         * TODO: wrap parameters into a message and
-         * dispatch it to all CPUs excluding this one.
-         */
+        for (i = 0; i < config.cpu_count; i++) {
+                cpu_t *cpu;
+                
+                if (i == CPU->id)
+                        continue;
+
+                cpu = &cpus[i];
+                spinlock_lock(&cpu->lock);
+                if (cpu->tlb_messages_count == TLB_MESSAGE_QUEUE_LEN) {
+                        /*
+                         * The message queue is full.
+                         * Erase the queue and store one TLB_INVL_ALL message.
+                         */
+                        cpu->tlb_messages_count = 1;
+                        cpu->tlb_messages[0].type = TLB_INVL_ALL;
+                        cpu->tlb_messages[0].asid = ASID_INVALID;
+                        cpu->tlb_messages[0].page = 0;
+                        cpu->tlb_messages[0].count = 0;
+                } else {
+                        /*
+                         * Enqueue the message.
+                         */
+                        cpu->tlb_messages[cpu->tlb_messages_count].type = type;
+                        cpu->tlb_messages[cpu->tlb_messages_count].asid = asid;
+                        cpu->tlb_messages[cpu->tlb_messages_count].page = page;
+                        cpu->tlb_messages[cpu->tlb_messages_count].count = count;
+                        cpu->tlb_messages_count++;
+                }
+                spinlock_unlock(&cpu->lock);
+        }
         
         tlb_shootdown_ipi_send();
 
 busy_wait:      
-        for (i = 0; i<config.cpu_count; i++)
+        for (i = 0; i < config.cpu_count; i++)
                 if (cpus[i].tlb_active)
                         goto busy_wait;
 }
 
+/** Finish TLB shootdown sequence. */
 void tlb_shootdown_finalize(void)
 {
@@ -78 +124 @@
 }
 
+/** Receive TLB shootdown message. */
 void tlb_shootdown_ipi_recv(void)
 {
+        tlb_invalidate_type_t type;
+        asid_t asid;
+        __address page;
+        count_t count;
+        int i;
+        
         CPU->tlb_active = 0;
         spinlock_lock(&tlblock);
         spinlock_unlock(&tlblock);
-        tlb_invalidate_all();   /* TODO: be more finer-grained in what to invalidate */
+        
+        spinlock_lock(&CPU->lock);
+        ASSERT(CPU->tlb_messages_count <= TLB_MESSAGE_QUEUE_LEN);
+
+        for (i = 0; i < CPU->tlb_messages_count; CPU->tlb_messages_count--) {
+                type = CPU->tlb_messages[i].type;
+                asid = CPU->tlb_messages[i].asid;
+                page = CPU->tlb_messages[i].page;
+                count = CPU->tlb_messages[i].count;
+
+                switch (type) {
+                    case TLB_INVL_ALL:
+                        tlb_invalidate_all();
+                        break;
+                    case TLB_INVL_ASID:
+                        tlb_invalidate_asid(asid);
+                        break;
+                    case TLB_INVL_PAGES:
+                        ASSERT(count);
+                        tlb_invalidate_pages(asid, page, count);
+                        break;
+                    default:
+                        panic("unknown type (%d)\n", type);
+                        break;
+                }
+                if (type == TLB_INVL_ALL)
+                        break;
+        }
+        
+        spinlock_unlock(&CPU->lock);
         CPU->tlb_active = 1;
 }
+
 #endif /* CONFIG_SMP */