remote_flush_tlb_array_cpumask(): bundle remote TLB invalidations

arch/x86/kernel/memory.c

@@ -1077,8 +1077,27 @@ struct clear_range_args {
 	int free_physical;
 	struct memobj *memobj;
 	struct process_vm *vm;
+	unsigned long *addr;
+	int nr_addr;
+	int max_nr_addr;
 };
 
+static void remote_flush_tlb_add_addr(struct clear_range_args *args,
+		unsigned long addr)
+{
+	if (args->nr_addr < args->max_nr_addr) {
+		args->addr[args->nr_addr] = addr;
+		++args->nr_addr;
+		return;
+	}
+
+	remote_flush_tlb_array_cpumask(args->vm, args->addr, args->nr_addr,
+			ihk_mc_get_processor_id());
+
+	args->addr[0] = addr;
+	args->nr_addr = 1;
+}
+
 static int clear_range_l1(void *args0, pte_t *ptep, uint64_t base,
 		uint64_t start, uint64_t end)
 {
@@ -1092,7 +1111,7 @@ static int clear_range_l1(void *args0, pte_t *ptep, uint64_t base,
 	}
 
 	old = xchg(ptep, PTE_NULL);
-	remote_flush_tlb_cpumask(args->vm, base, ihk_mc_get_processor_id());
+	remote_flush_tlb_add_addr(args, base);
 
 	page = NULL;
 	if (!pte_is_fileoff(&old, PTL1_SIZE)) {
@@ -1141,8 +1160,7 @@ static int clear_range_l2(void *args0, pte_t *ptep, uint64_t base,
 
 	if (*ptep & PFL2_SIZE) {
 		old = xchg(ptep, PTE_NULL);
-		remote_flush_tlb_cpumask(args->vm, base,
-				ihk_mc_get_processor_id());
+		remote_flush_tlb_add_addr(args, base);
 
 		page = NULL;
 		if (!pte_is_fileoff(&old, PTL2_SIZE)) {
@@ -1174,8 +1192,7 @@ static int clear_range_l2(void *args0, pte_t *ptep, uint64_t base,
 
 	if ((start <= base) && ((base + PTL2_SIZE) <= end)) {
 		*ptep = PTE_NULL;
-		remote_flush_tlb_cpumask(args->vm, base,
-				ihk_mc_get_processor_id());
+		remote_flush_tlb_add_addr(args, base);
 		ihk_mc_free_pages(pt, 1);
 	}
 
@@ -1207,8 +1224,7 @@ static int clear_range_l3(void *args0, pte_t *ptep, uint64_t base,
 
 	if (*ptep & PFL3_SIZE) {
 		old = xchg(ptep, PTE_NULL);
-		remote_flush_tlb_cpumask(args->vm, base,
-				ihk_mc_get_processor_id());
+		remote_flush_tlb_add_addr(args, base);
 
 		page = NULL;
 		if (!pte_is_fileoff(&old, PTL3_SIZE)) {
@@ -1239,8 +1255,7 @@ static int clear_range_l3(void *args0, pte_t *ptep, uint64_t base,
 
 	if (use_1gb_page && (start <= base) && ((base + PTL3_SIZE) <= end)) {
 		*ptep = PTE_NULL;
-		remote_flush_tlb_cpumask(args->vm, base,
-				ihk_mc_get_processor_id());
+		remote_flush_tlb_add_addr(args, base);
 		ihk_mc_free_pages(pt, 1);
 	}
 
@@ -1260,6 +1275,8 @@ static int clear_range_l4(void *args0, pte_t *ptep, uint64_t base,
 	return walk_pte_l3(pt, base, start, end, &clear_range_l3, args0);
 }
 
+#define TLB_INVALID_ARRAY_PAGES	(4)
+
 static int clear_range(struct page_table *pt, struct process_vm *vm,
 		uintptr_t start, uintptr_t end, int free_physical,
 		struct memobj *memobj)
@@ -1276,6 +1293,17 @@ static int clear_range(struct page_table *pt, struct process_vm *vm,
 		return -EINVAL;
 	}
 
+	/* TODO: embedd this in tlb_flush_entry? */
+	args.addr = (unsigned long *)ihk_mc_alloc_pages(
+			TLB_INVALID_ARRAY_PAGES, IHK_MC_AP_CRITICAL);
+	if (!args.addr) {
+		ekprintf("%s: error: allocating address array\n", __FUNCTION__);
+		return -ENOMEM;
+	}
+	args.nr_addr = 0;
+	args.max_nr_addr = (TLB_INVALID_ARRAY_PAGES * PAGE_SIZE /
+			sizeof(uint64_t));
+
 	args.free_physical = free_physical;
 	if (memobj && (memobj->flags & MF_DEV_FILE)) {
 		args.free_physical = 0;
@@ -1287,6 +1315,13 @@ static int clear_range(struct page_table *pt, struct process_vm *vm,
 	args.vm = vm;
 
 	error = walk_pte_l4(pt, 0, start, end, &clear_range_l4, &args);
+	if (args.nr_addr) {
+		remote_flush_tlb_array_cpumask(vm, args.addr, args.nr_addr,
+				ihk_mc_get_processor_id());
+	}
+
+	ihk_mc_free_pages(args.addr, TLB_INVALID_ARRAY_PAGES);
+
 	return error;
 }
 

kernel/mem.c

@@ -887,14 +887,23 @@ void coredump(struct thread *thread, void *regs)
 
 void remote_flush_tlb_cpumask(struct process_vm *vm,
 		unsigned long addr, int cpu_id)
+{
+	unsigned long __addr = addr;
+	return remote_flush_tlb_array_cpumask(vm, &__addr, 1, cpu_id);
+}
+
+void remote_flush_tlb_array_cpumask(struct process_vm *vm,
+		unsigned long *addr,
+		int nr_addr,
+		int cpu_id)
 {
 	unsigned long cpu;
 	int flush_ind;
 	struct tlb_flush_entry *flush_entry;
 	cpu_set_t _cpu_set;
 
-	if (addr) {
-		flush_ind = (addr >> PAGE_SHIFT) % IHK_TLB_FLUSH_IRQ_VECTOR_SIZE;
+	if (addr[0]) {
+		flush_ind = (addr[0] >> PAGE_SHIFT) % IHK_TLB_FLUSH_IRQ_VECTOR_SIZE;
 	}
 	/* Zero address denotes full TLB flush */
 	else {
@@ -916,6 +925,7 @@ void remote_flush_tlb_cpumask(struct process_vm *vm,
 
 	flush_entry->vm = vm;
 	flush_entry->addr = addr;
+	flush_entry->nr_addr = nr_addr;
 	ihk_atomic_set(&flush_entry->pending, 0);
 
 	dkprintf("lock aquired, iterating cpu mask.. flush_ind: %d\n", flush_ind);
@@ -940,16 +950,18 @@ void remote_flush_tlb_cpumask(struct process_vm *vm,
 		unsigned long tsc;
 		tsc = rdtsc() + 12884901888;  /* 1.2GHz =>10 sec */
 #endif
-		if (flush_entry->addr) {
-			flush_tlb_single(flush_entry->addr & PAGE_MASK);
+		if (flush_entry->addr[0]) {
+			int i;
+
+			for (i = 0; i < flush_entry->nr_addr; ++i) {
+				flush_tlb_single(flush_entry->addr[i] & PAGE_MASK);
+			}
 		}
 		/* Zero address denotes full TLB flush */
 		else {
 			flush_tlb();
 		}
 
-		/* Flush on this core */
-		flush_tlb_single(addr & PAGE_MASK);
 		/* Wait for all cores */
 		while (ihk_atomic_read(&flush_entry->pending) != 0) {
 			cpu_pause();
@@ -978,22 +990,24 @@ void tlb_flush_handler(int vector)
 	struct tlb_flush_entry *flush_entry = &tlb_flush_vector[vector -
 		IHK_TLB_FLUSH_IRQ_VECTOR_START];
 
-	dkprintf("decreasing pending cnt for %d\n", 
-			vector - IHK_TLB_FLUSH_IRQ_VECTOR_START);
+	if (flush_entry->addr[0]) {
+		int i;
 
-	/* Decrease counter */
-	ihk_atomic_dec(&flush_entry->pending);
-
-	dkprintf("flusing TLB for addr: 0x%lX\n", flush_entry->addr);
-		
-	if (flush_entry->addr) {
-		flush_tlb_single(flush_entry->addr & PAGE_MASK);	
+		for (i = 0; i < flush_entry->nr_addr; ++i) {
+			flush_tlb_single(flush_entry->addr[i] & PAGE_MASK);
+			dkprintf("flusing TLB for addr: 0x%lX\n", flush_entry->addr[i]);
+		}
 	}
 	/* Zero address denotes full TLB flush */
 	else {
 		flush_tlb();
 	}
 
+	/* Decrease counter */
+	dkprintf("decreasing pending cnt for %d\n",
+			vector - IHK_TLB_FLUSH_IRQ_VECTOR_START);
+	ihk_atomic_dec(&flush_entry->pending);
+
 	cpu_restore_interrupt(flags);
 #ifdef PROFILE_ENABLE
 	{

lib/include/ihk/mm.h

@@ -215,6 +215,10 @@ int ihk_mc_get_memory_chunk(int id,
 
 void remote_flush_tlb_cpumask(struct process_vm *vm, 
 		unsigned long addr, int cpu_id);
+void remote_flush_tlb_array_cpumask(struct process_vm *vm,
+		unsigned long *addr,
+		int nr_addr,
+		int cpu_id);
 
 int ihk_set_kmsg(unsigned long addr, unsigned long size);
 char *ihk_get_kargs();
@@ -226,7 +230,8 @@ extern void (*__tlb_flush_handler)(int vector);
 
 struct tlb_flush_entry {
 	struct process_vm *vm;
-	unsigned long addr;
+	unsigned long *addr;
+	int nr_addr;
 	ihk_atomic_t pending;
 	ihk_spinlock_t lock;
 } __attribute__((aligned(64)));