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-rw-r--r--arch/x86/mm/Makefile2
-rw-r--r--arch/x86/mm/extable.c6
-rw-r--r--arch/x86/mm/fault.c7
-rw-r--r--arch/x86/mm/init_32.c135
-rw-r--r--arch/x86/mm/ioremap.c2
-rw-r--r--arch/x86/mm/mmap.c2
-rw-r--r--arch/x86/mm/numa_64.c217
-rw-r--r--arch/x86/mm/pat.c31
-rw-r--r--arch/x86/mm/srat_64.c1
-rw-r--r--arch/x86/mm/tlb.c296
10 files changed, 629 insertions, 70 deletions
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index d8cc96a2..2b938a3 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -1,6 +1,8 @@
obj-y := init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
pat.o pgtable.o gup.o
+obj-$(CONFIG_SMP) += tlb.o
+
obj-$(CONFIG_X86_32) += pgtable_32.o iomap_32.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 7e8db53..61b41ca 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -23,6 +23,12 @@ int fixup_exception(struct pt_regs *regs)
fixup = search_exception_tables(regs->ip);
if (fixup) {
+ /* If fixup is less than 16, it means uaccess error */
+ if (fixup->fixup < 16) {
+ current_thread_info()->uaccess_err = -EFAULT;
+ regs->ip += fixup->fixup;
+ return 1;
+ }
regs->ip = fixup->fixup;
return 1;
}
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 817a78d..94c4e72 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -26,6 +26,7 @@
#include <linux/kprobes.h>
#include <linux/uaccess.h>
#include <linux/kdebug.h>
+#include <linux/magic.h>
#include <asm/system.h>
#include <asm/desc.h>
@@ -432,6 +433,8 @@ static noinline void no_context(struct pt_regs *regs,
unsigned long error_code, unsigned long address)
{
struct task_struct *tsk = current;
+ unsigned long *stackend;
+
#ifdef CONFIG_X86_64
unsigned long flags;
int sig;
@@ -468,6 +471,10 @@ static noinline void no_context(struct pt_regs *regs,
show_fault_oops(regs, error_code, address);
+ stackend = end_of_stack(tsk);
+ if (*stackend != STACK_END_MAGIC)
+ printk(KERN_ALERT "Thread overran stack, or stack corrupted\n");
+
tsk->thread.cr2 = address;
tsk->thread.trap_no = 14;
tsk->thread.error_code = error_code;
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 2cef050..06708ee 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -49,7 +49,6 @@
#include <asm/paravirt.h>
#include <asm/setup.h>
#include <asm/cacheflush.h>
-#include <asm/smp.h>
unsigned int __VMALLOC_RESERVE = 128 << 20;
@@ -675,75 +674,97 @@ static int __init parse_highmem(char *arg)
}
early_param("highmem", parse_highmem);
+#define MSG_HIGHMEM_TOO_BIG \
+ "highmem size (%luMB) is bigger than pages available (%luMB)!\n"
+
+#define MSG_LOWMEM_TOO_SMALL \
+ "highmem size (%luMB) results in <64MB lowmem, ignoring it!\n"
/*
- * Determine low and high memory ranges:
+ * All of RAM fits into lowmem - but if user wants highmem
+ * artificially via the highmem=x boot parameter then create
+ * it:
*/
-void __init find_low_pfn_range(void)
+void __init lowmem_pfn_init(void)
{
- /* it could update max_pfn */
-
/* max_low_pfn is 0, we already have early_res support */
-
max_low_pfn = max_pfn;
- if (max_low_pfn > MAXMEM_PFN) {
- if (highmem_pages == -1)
- highmem_pages = max_pfn - MAXMEM_PFN;
- if (highmem_pages + MAXMEM_PFN < max_pfn)
- max_pfn = MAXMEM_PFN + highmem_pages;
- if (highmem_pages + MAXMEM_PFN > max_pfn) {
- printk(KERN_WARNING "only %luMB highmem pages "
- "available, ignoring highmem size of %uMB.\n",
- pages_to_mb(max_pfn - MAXMEM_PFN),
+
+ if (highmem_pages == -1)
+ highmem_pages = 0;
+#ifdef CONFIG_HIGHMEM
+ if (highmem_pages >= max_pfn) {
+ printk(KERN_ERR MSG_HIGHMEM_TOO_BIG,
+ pages_to_mb(highmem_pages), pages_to_mb(max_pfn));
+ highmem_pages = 0;
+ }
+ if (highmem_pages) {
+ if (max_low_pfn - highmem_pages < 64*1024*1024/PAGE_SIZE) {
+ printk(KERN_ERR MSG_LOWMEM_TOO_SMALL,
pages_to_mb(highmem_pages));
highmem_pages = 0;
}
- max_low_pfn = MAXMEM_PFN;
+ max_low_pfn -= highmem_pages;
+ }
+#else
+ if (highmem_pages)
+ printk(KERN_ERR "ignoring highmem size on non-highmem kernel!\n");
+#endif
+}
+
+#define MSG_HIGHMEM_TOO_SMALL \
+ "only %luMB highmem pages available, ignoring highmem size of %luMB!\n"
+
+#define MSG_HIGHMEM_TRIMMED \
+ "Warning: only 4GB will be used. Use a HIGHMEM64G enabled kernel!\n"
+/*
+ * We have more RAM than fits into lowmem - we try to put it into
+ * highmem, also taking the highmem=x boot parameter into account:
+ */
+void __init highmem_pfn_init(void)
+{
+ max_low_pfn = MAXMEM_PFN;
+
+ if (highmem_pages == -1)
+ highmem_pages = max_pfn - MAXMEM_PFN;
+
+ if (highmem_pages + MAXMEM_PFN < max_pfn)
+ max_pfn = MAXMEM_PFN + highmem_pages;
+
+ if (highmem_pages + MAXMEM_PFN > max_pfn) {
+ printk(KERN_WARNING MSG_HIGHMEM_TOO_SMALL,
+ pages_to_mb(max_pfn - MAXMEM_PFN),
+ pages_to_mb(highmem_pages));
+ highmem_pages = 0;
+ }
#ifndef CONFIG_HIGHMEM
- /* Maximum memory usable is what is directly addressable */
- printk(KERN_WARNING "Warning only %ldMB will be used.\n",
- MAXMEM>>20);
- if (max_pfn > MAX_NONPAE_PFN)
- printk(KERN_WARNING
- "Use a HIGHMEM64G enabled kernel.\n");
- else
- printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
- max_pfn = MAXMEM_PFN;
+ /* Maximum memory usable is what is directly addressable */
+ printk(KERN_WARNING "Warning only %ldMB will be used.\n", MAXMEM>>20);
+ if (max_pfn > MAX_NONPAE_PFN)
+ printk(KERN_WARNING "Use a HIGHMEM64G enabled kernel.\n");
+ else
+ printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
+ max_pfn = MAXMEM_PFN;
#else /* !CONFIG_HIGHMEM */
#ifndef CONFIG_HIGHMEM64G
- if (max_pfn > MAX_NONPAE_PFN) {
- max_pfn = MAX_NONPAE_PFN;
- printk(KERN_WARNING "Warning only 4GB will be used."
- "Use a HIGHMEM64G enabled kernel.\n");
- }
+ if (max_pfn > MAX_NONPAE_PFN) {
+ max_pfn = MAX_NONPAE_PFN;
+ printk(KERN_WARNING MSG_HIGHMEM_TRIMMED);
+ }
#endif /* !CONFIG_HIGHMEM64G */
#endif /* !CONFIG_HIGHMEM */
- } else {
- if (highmem_pages == -1)
- highmem_pages = 0;
-#ifdef CONFIG_HIGHMEM
- if (highmem_pages >= max_pfn) {
- printk(KERN_ERR "highmem size specified (%uMB) is "
- "bigger than pages available (%luMB)!.\n",
- pages_to_mb(highmem_pages),
- pages_to_mb(max_pfn));
- highmem_pages = 0;
- }
- if (highmem_pages) {
- if (max_low_pfn - highmem_pages <
- 64*1024*1024/PAGE_SIZE){
- printk(KERN_ERR "highmem size %uMB results in "
- "smaller than 64MB lowmem, ignoring it.\n"
- , pages_to_mb(highmem_pages));
- highmem_pages = 0;
- }
- max_low_pfn -= highmem_pages;
- }
-#else
- if (highmem_pages)
- printk(KERN_ERR "ignoring highmem size on non-highmem"
- " kernel!\n");
-#endif
- }
+}
+
+/*
+ * Determine low and high memory ranges:
+ */
+void __init find_low_pfn_range(void)
+{
+ /* it could update max_pfn */
+
+ if (max_pfn <= MAXMEM_PFN)
+ lowmem_pfn_init();
+ else
+ highmem_pfn_init();
}
#ifndef CONFIG_NEED_MULTIPLE_NODES
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index af750ab..1448bcb 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -367,7 +367,7 @@ EXPORT_SYMBOL(ioremap_nocache);
*
* Must be freed with iounmap.
*/
-void __iomem *ioremap_wc(unsigned long phys_addr, unsigned long size)
+void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
{
if (pat_enabled)
return __ioremap_caller(phys_addr, size, _PAGE_CACHE_WC,
diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 56fe712..1658296 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -4,7 +4,7 @@
* Based on code by Ingo Molnar and Andi Kleen, copyrighted
* as follows:
*
- * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
+ * Copyright 2003-2009 Red Hat Inc.
* All Rights Reserved.
* Copyright 2005 Andi Kleen, SUSE Labs.
* Copyright 2007 Jiri Kosina, SUSE Labs.
diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c
index 71a14f8..deb1c1a 100644
--- a/arch/x86/mm/numa_64.c
+++ b/arch/x86/mm/numa_64.c
@@ -20,6 +20,12 @@
#include <asm/acpi.h>
#include <asm/k8.h>
+#ifdef CONFIG_DEBUG_PER_CPU_MAPS
+# define DBG(x...) printk(KERN_DEBUG x)
+#else
+# define DBG(x...)
+#endif
+
struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
EXPORT_SYMBOL(node_data);
@@ -33,6 +39,21 @@ int numa_off __initdata;
static unsigned long __initdata nodemap_addr;
static unsigned long __initdata nodemap_size;
+DEFINE_PER_CPU(int, node_number) = 0;
+EXPORT_PER_CPU_SYMBOL(node_number);
+
+/*
+ * Map cpu index to node index
+ */
+DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
+EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
+
+/*
+ * Which logical CPUs are on which nodes
+ */
+cpumask_t *node_to_cpumask_map;
+EXPORT_SYMBOL(node_to_cpumask_map);
+
/*
* Given a shift value, try to populate memnodemap[]
* Returns :
@@ -640,3 +661,199 @@ void __init init_cpu_to_node(void)
#endif
+/*
+ * Allocate node_to_cpumask_map based on number of available nodes
+ * Requires node_possible_map to be valid.
+ *
+ * Note: node_to_cpumask() is not valid until after this is done.
+ * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
+ */
+void __init setup_node_to_cpumask_map(void)
+{
+ unsigned int node, num = 0;
+ cpumask_t *map;
+
+ /* setup nr_node_ids if not done yet */
+ if (nr_node_ids == MAX_NUMNODES) {
+ for_each_node_mask(node, node_possible_map)
+ num = node;
+ nr_node_ids = num + 1;
+ }
+
+ /* allocate the map */
+ map = alloc_bootmem_low(nr_node_ids * sizeof(cpumask_t));
+ DBG("node_to_cpumask_map at %p for %d nodes\n", map, nr_node_ids);
+
+ pr_debug("Node to cpumask map at %p for %d nodes\n",
+ map, nr_node_ids);
+
+ /* node_to_cpumask() will now work */
+ node_to_cpumask_map = map;
+}
+
+void __cpuinit numa_set_node(int cpu, int node)
+{
+ int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
+
+ /* early setting, no percpu area yet */
+ if (cpu_to_node_map) {
+ cpu_to_node_map[cpu] = node;
+ return;
+ }
+
+#ifdef CONFIG_DEBUG_PER_CPU_MAPS
+ if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) {
+ printk(KERN_ERR "numa_set_node: invalid cpu# (%d)\n", cpu);
+ dump_stack();
+ return;
+ }
+#endif
+ per_cpu(x86_cpu_to_node_map, cpu) = node;
+
+ if (node != NUMA_NO_NODE)
+ per_cpu(node_number, cpu) = node;
+}
+
+void __cpuinit numa_clear_node(int cpu)
+{
+ numa_set_node(cpu, NUMA_NO_NODE);
+}
+
+#ifndef CONFIG_DEBUG_PER_CPU_MAPS
+
+void __cpuinit numa_add_cpu(int cpu)
+{
+ cpu_set(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
+}
+
+void __cpuinit numa_remove_cpu(int cpu)
+{
+ cpu_clear(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
+}
+
+#else /* CONFIG_DEBUG_PER_CPU_MAPS */
+
+/*
+ * --------- debug versions of the numa functions ---------
+ */
+static void __cpuinit numa_set_cpumask(int cpu, int enable)
+{
+ int node = early_cpu_to_node(cpu);
+ cpumask_t *mask;
+ char buf[64];
+
+ if (node_to_cpumask_map == NULL) {
+ printk(KERN_ERR "node_to_cpumask_map NULL\n");
+ dump_stack();
+ return;
+ }
+
+ mask = &node_to_cpumask_map[node];
+ if (enable)
+ cpu_set(cpu, *mask);
+ else
+ cpu_clear(cpu, *mask);
+
+ cpulist_scnprintf(buf, sizeof(buf), mask);
+ printk(KERN_DEBUG "%s cpu %d node %d: mask now %s\n",
+ enable ? "numa_add_cpu" : "numa_remove_cpu", cpu, node, buf);
+}
+
+void __cpuinit numa_add_cpu(int cpu)
+{
+ numa_set_cpumask(cpu, 1);
+}
+
+void __cpuinit numa_remove_cpu(int cpu)
+{
+ numa_set_cpumask(cpu, 0);
+}
+
+int cpu_to_node(int cpu)
+{
+ if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
+ printk(KERN_WARNING
+ "cpu_to_node(%d): usage too early!\n", cpu);
+ dump_stack();
+ return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
+ }
+ return per_cpu(x86_cpu_to_node_map, cpu);
+}
+EXPORT_SYMBOL(cpu_to_node);
+
+/*
+ * Same function as cpu_to_node() but used if called before the
+ * per_cpu areas are setup.
+ */
+int early_cpu_to_node(int cpu)
+{
+ if (early_per_cpu_ptr(x86_cpu_to_node_map))
+ return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
+
+ if (!cpu_possible(cpu)) {
+ printk(KERN_WARNING
+ "early_cpu_to_node(%d): no per_cpu area!\n", cpu);
+ dump_stack();
+ return NUMA_NO_NODE;
+ }
+ return per_cpu(x86_cpu_to_node_map, cpu);
+}
+
+
+/* empty cpumask */
+static const cpumask_t cpu_mask_none;
+
+/*
+ * Returns a pointer to the bitmask of CPUs on Node 'node'.
+ */
+const cpumask_t *cpumask_of_node(int node)
+{
+ if (node_to_cpumask_map == NULL) {
+ printk(KERN_WARNING
+ "cpumask_of_node(%d): no node_to_cpumask_map!\n",
+ node);
+ dump_stack();
+ return (const cpumask_t *)&cpu_online_map;
+ }
+ if (node >= nr_node_ids) {
+ printk(KERN_WARNING
+ "cpumask_of_node(%d): node > nr_node_ids(%d)\n",
+ node, nr_node_ids);
+ dump_stack();
+ return &cpu_mask_none;
+ }
+ return &node_to_cpumask_map[node];
+}
+EXPORT_SYMBOL(cpumask_of_node);
+
+/*
+ * Returns a bitmask of CPUs on Node 'node'.
+ *
+ * Side note: this function creates the returned cpumask on the stack
+ * so with a high NR_CPUS count, excessive stack space is used. The
+ * node_to_cpumask_ptr function should be used whenever possible.
+ */
+cpumask_t node_to_cpumask(int node)
+{
+ if (node_to_cpumask_map == NULL) {
+ printk(KERN_WARNING
+ "node_to_cpumask(%d): no node_to_cpumask_map!\n", node);
+ dump_stack();
+ return cpu_online_map;
+ }
+ if (node >= nr_node_ids) {
+ printk(KERN_WARNING
+ "node_to_cpumask(%d): node > nr_node_ids(%d)\n",
+ node, nr_node_ids);
+ dump_stack();
+ return cpu_mask_none;
+ }
+ return node_to_cpumask_map[node];
+}
+EXPORT_SYMBOL(node_to_cpumask);
+
+/*
+ * --------- end of debug versions of the numa functions ---------
+ */
+
+#endif /* CONFIG_DEBUG_PER_CPU_MAPS */
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 7b61036..9127e31 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -30,7 +30,7 @@
#ifdef CONFIG_X86_PAT
int __read_mostly pat_enabled = 1;
-void __cpuinit pat_disable(char *reason)
+void __cpuinit pat_disable(const char *reason)
{
pat_enabled = 0;
printk(KERN_INFO "%s\n", reason);
@@ -42,6 +42,11 @@ static int __init nopat(char *str)
return 0;
}
early_param("nopat", nopat);
+#else
+static inline void pat_disable(const char *reason)
+{
+ (void)reason;
+}
#endif
@@ -78,16 +83,20 @@ void pat_init(void)
if (!pat_enabled)
return;
- /* Paranoia check. */
- if (!cpu_has_pat && boot_pat_state) {
- /*
- * If this happens we are on a secondary CPU, but
- * switched to PAT on the boot CPU. We have no way to
- * undo PAT.
- */
- printk(KERN_ERR "PAT enabled, "
- "but not supported by secondary CPU\n");
- BUG();
+ if (!cpu_has_pat) {
+ if (!boot_pat_state) {
+ pat_disable("PAT not supported by CPU.");
+ return;
+ } else {
+ /*
+ * If this happens we are on a secondary CPU, but
+ * switched to PAT on the boot CPU. We have no way to
+ * undo PAT.
+ */
+ printk(KERN_ERR "PAT enabled, "
+ "but not supported by secondary CPU\n");
+ BUG();
+ }
}
/* Set PWT to Write-Combining. All other bits stay the same */
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
index 09737c8..15df1bae 100644
--- a/arch/x86/mm/srat_64.c
+++ b/arch/x86/mm/srat_64.c
@@ -21,6 +21,7 @@
#include <asm/numa.h>
#include <asm/e820.h>
#include <asm/genapic.h>
+#include <asm/uv/uv.h>
int acpi_numa __initdata;
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
new file mode 100644
index 0000000..14c5af4
--- /dev/null
+++ b/arch/x86/mm/tlb.c
@@ -0,0 +1,296 @@
+#include <linux/init.h>
+
+#include <linux/mm.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+#include <asm/apic.h>
+#include <asm/uv/uv.h>
+
+DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate)
+ = { &init_mm, 0, };
+
+#include <asm/genapic.h>
+/*
+ * Smarter SMP flushing macros.
+ * c/o Linus Torvalds.
+ *
+ * These mean you can really definitely utterly forget about
+ * writing to user space from interrupts. (Its not allowed anyway).
+ *
+ * Optimizations Manfred Spraul <manfred@colorfullife.com>
+ *
+ * More scalable flush, from Andi Kleen
+ *
+ * To avoid global state use 8 different call vectors.
+ * Each CPU uses a specific vector to trigger flushes on other
+ * CPUs. Depending on the received vector the target CPUs look into
+ * the right array slot for the flush data.
+ *
+ * With more than 8 CPUs they are hashed to the 8 available
+ * vectors. The limited global vector space forces us to this right now.
+ * In future when interrupts are split into per CPU domains this could be
+ * fixed, at the cost of triggering multiple IPIs in some cases.
+ */
+
+union smp_flush_state {
+ struct {
+ struct mm_struct *flush_mm;
+ unsigned long flush_va;
+ spinlock_t tlbstate_lock;
+ DECLARE_BITMAP(flush_cpumask, NR_CPUS);
+ };
+ char pad[CONFIG_X86_INTERNODE_CACHE_BYTES];
+} ____cacheline_internodealigned_in_smp;
+
+/* State is put into the per CPU data section, but padded
+ to a full cache line because other CPUs can access it and we don't
+ want false sharing in the per cpu data segment. */
+static union smp_flush_state flush_state[NUM_INVALIDATE_TLB_VECTORS];
+
+/*
+ * We cannot call mmdrop() because we are in interrupt context,
+ * instead update mm->cpu_vm_mask.
+ */
+void leave_mm(int cpu)
+{
+ if (percpu_read(cpu_tlbstate.state) == TLBSTATE_OK)
+ BUG();
+ cpu_clear(cpu, percpu_read(cpu_tlbstate.active_mm)->cpu_vm_mask);
+ load_cr3(swapper_pg_dir);
+}
+EXPORT_SYMBOL_GPL(leave_mm);
+
+/*
+ *
+ * The flush IPI assumes that a thread switch happens in this order:
+ * [cpu0: the cpu that switches]
+ * 1) switch_mm() either 1a) or 1b)
+ * 1a) thread switch to a different mm
+ * 1a1) cpu_clear(cpu, old_mm->cpu_vm_mask);
+ * Stop ipi delivery for the old mm. This is not synchronized with
+ * the other cpus, but smp_invalidate_interrupt ignore flush ipis
+ * for the wrong mm, and in the worst case we perform a superfluous
+ * tlb flush.
+ * 1a2) set cpu mmu_state to TLBSTATE_OK
+ * Now the smp_invalidate_interrupt won't call leave_mm if cpu0
+ * was in lazy tlb mode.
+ * 1a3) update cpu active_mm
+ * Now cpu0 accepts tlb flushes for the new mm.
+ * 1a4) cpu_set(cpu, new_mm->cpu_vm_mask);
+ * Now the other cpus will send tlb flush ipis.
+ * 1a4) change cr3.
+ * 1b) thread switch without mm change
+ * cpu active_mm is correct, cpu0 already handles
+ * flush ipis.
+ * 1b1) set cpu mmu_state to TLBSTATE_OK
+ * 1b2) test_and_set the cpu bit in cpu_vm_mask.
+ * Atomically set the bit [other cpus will start sending flush ipis],
+ * and test the bit.
+ * 1b3) if the bit was 0: leave_mm was called, flush the tlb.
+ * 2) switch %%esp, ie current
+ *
+ * The interrupt must handle 2 special cases:
+ * - cr3 is changed before %%esp, ie. it cannot use current->{active_,}mm.
+ * - the cpu performs speculative tlb reads, i.e. even if the cpu only
+ * runs in kernel space, the cpu could load tlb entries for user space
+ * pages.
+ *
+ * The good news is that cpu mmu_state is local to each cpu, no
+ * write/read ordering problems.
+ */
+
+/*
+ * TLB flush IPI:
+ *
+ * 1) Flush the tlb entries if the cpu uses the mm that's being flushed.
+ * 2) Leave the mm if we are in the lazy tlb mode.
+ *
+ * Interrupts are disabled.
+ */
+
+/*
+ * FIXME: use of asmlinkage is not consistent. On x86_64 it's noop
+ * but still used for documentation purpose but the usage is slightly
+ * inconsistent. On x86_32, asmlinkage is regparm(0) but interrupt
+ * entry calls in with the first parameter in %eax. Maybe define
+ * intrlinkage?
+ */
+#ifdef CONFIG_X86_64
+asmlinkage
+#endif
+void smp_invalidate_interrupt(struct pt_regs *regs)
+{
+ unsigned int cpu;
+ unsigned int sender;
+ union smp_flush_state *f;
+
+ cpu = smp_processor_id();
+ /*
+ * orig_rax contains the negated interrupt vector.
+ * Use that to determine where the sender put the data.
+ */
+ sender = ~regs->orig_ax - INVALIDATE_TLB_VECTOR_START;
+ f = &flush_state[sender];
+
+ if (!cpumask_test_cpu(cpu, to_cpumask(f->flush_cpumask)))
+ goto out;
+ /*
+ * This was a BUG() but until someone can quote me the
+ * line from the intel manual that guarantees an IPI to
+ * multiple CPUs is retried _only_ on the erroring CPUs
+ * its staying as a return
+ *
+ * BUG();
+ */
+
+ if (f->flush_mm == percpu_read(cpu_tlbstate.active_mm)) {
+ if (percpu_read(cpu_tlbstate.state) == TLBSTATE_OK) {
+ if (f->flush_va == TLB_FLUSH_ALL)
+ local_flush_tlb();
+ else
+ __flush_tlb_one(f->flush_va);
+ } else
+ leave_mm(cpu);
+ }
+out:
+ ack_APIC_irq();
+ smp_mb__before_clear_bit();
+ cpumask_clear_cpu(cpu, to_cpumask(f->flush_cpumask));
+ smp_mb__after_clear_bit();
+ inc_irq_stat(irq_tlb_count);
+}
+
+static void flush_tlb_others_ipi(const struct cpumask *cpumask,
+ struct mm_struct *mm, unsigned long va)
+{
+ unsigned int sender;
+ union smp_flush_state *f;
+
+ /* Caller has disabled preemption */
+ sender = smp_processor_id() % NUM_INVALIDATE_TLB_VECTORS;
+ f = &flush_state[sender];
+
+ /*
+ * Could avoid this lock when
+ * num_online_cpus() <= NUM_INVALIDATE_TLB_VECTORS, but it is
+ * probably not worth checking this for a cache-hot lock.
+ */
+ spin_lock(&f->tlbstate_lock);
+
+ f->flush_mm = mm;
+ f->flush_va = va;
+ cpumask_andnot(to_cpumask(f->flush_cpumask),
+ cpumask, cpumask_of(smp_processor_id()));
+
+ /*
+ * Make the above memory operations globally visible before
+ * sending the IPI.
+ */
+ smp_mb();
+ /*
+ * We have to send the IPI only to
+ * CPUs affected.
+ */
+ apic->send_IPI_mask(to_cpumask(f->flush_cpumask),
+ INVALIDATE_TLB_VECTOR_START + sender);
+
+ while (!cpumask_empty(to_cpumask(f->flush_cpumask)))
+ cpu_relax();
+
+ f->flush_mm = NULL;
+ f->flush_va = 0;
+ spin_unlock(&f->tlbstate_lock);
+}
+
+void native_flush_tlb_others(const struct cpumask *cpumask,
+ struct mm_struct *mm, unsigned long va)
+{
+ if (is_uv_system()) {
+ unsigned int cpu;
+
+ cpu = get_cpu();
+ cpumask = uv_flush_tlb_others(cpumask, mm, va, cpu);
+ if (cpumask)
+ flush_tlb_others_ipi(cpumask, mm, va);
+ put_cpu();
+ return;
+ }
+ flush_tlb_others_ipi(cpumask, mm, va);
+}
+
+static int __cpuinit init_smp_flush(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(flush_state); i++)
+ spin_lock_init(&flush_state[i].tlbstate_lock);
+
+ return 0;
+}
+core_initcall(init_smp_flush);
+
+void flush_tlb_current_task(void)
+{
+ struct mm_struct *mm = current->mm;
+
+ preempt_disable();
+
+ local_flush_tlb();
+ if (cpumask_any_but(&mm->cpu_vm_mask, smp_processor_id()) < nr_cpu_ids)
+ flush_tlb_others(&mm->cpu_vm_mask, mm, TLB_FLUSH_ALL);
+ preempt_enable();
+}
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+ preempt_disable();
+
+ if (current->active_mm == mm) {
+ if (current->mm)
+ local_flush_tlb();
+ else
+ leave_mm(smp_processor_id());
+ }
+ if (cpumask_any_but(&mm->cpu_vm_mask, smp_processor_id()) < nr_cpu_ids)
+ flush_tlb_others(&mm->cpu_vm_mask, mm, TLB_FLUSH_ALL);
+
+ preempt_enable();
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long va)
+{
+ struct mm_struct *mm = vma->vm_mm;
+
+ preempt_disable();
+
+ if (current->active_mm == mm) {
+ if (current->mm)
+ __flush_tlb_one(va);
+ else
+ leave_mm(smp_processor_id());
+ }
+
+ if (cpumask_any_but(&mm->cpu_vm_mask, smp_processor_id()) < nr_cpu_ids)
+ flush_tlb_others(&mm->cpu_vm_mask, mm, va);
+
+ preempt_enable();
+}
+
+static void do_flush_tlb_all(void *info)
+{
+ unsigned long cpu = smp_processor_id();
+
+ __flush_tlb_all();
+ if (percpu_read(cpu_tlbstate.state) == TLBSTATE_LAZY)
+ leave_mm(cpu);
+}
+
+void flush_tlb_all(void)
+{
+ on_each_cpu(do_flush_tlb_all, NULL, 1);
+}
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