Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
authorLinus Torvalds <torvalds@linux-foundation.org>
Mon, 18 May 2009 16:17:37 +0000 (09:17 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 18 May 2009 16:17:37 +0000 (09:17 -0700)
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Fix performance regression caused by paravirt_ops on native kernels
  xen: use header for EXPORT_SYMBOL_GPL
  x86, 32-bit: fix kernel_trap_sp()
  x86: fix percpu_{to,from}_op()
  x86: mtrr: Fix high_width computation when phys-addr is >= 44bit
  x86: Fix false positive section mismatch warnings in the apic code

13 files changed:
arch/x86/Kconfig
arch/x86/include/asm/paravirt.h
arch/x86/include/asm/percpu.h
arch/x86/include/asm/ptrace.h
arch/x86/include/asm/spinlock.h
arch/x86/kernel/Makefile
arch/x86/kernel/apic/es7000_32.c
arch/x86/kernel/cpu/mtrr/generic.c
arch/x86/kernel/paravirt.c
arch/x86/oprofile/backtrace.c
arch/x86/xen/Makefile
arch/x86/xen/mmu.c
arch/x86/xen/xen-ops.h

index df9e885..a6efe0a 100644 (file)
@@ -498,6 +498,19 @@ config PARAVIRT
          over full virtualization.  However, when run without a hypervisor
          the kernel is theoretically slower and slightly larger.
 
+config PARAVIRT_SPINLOCKS
+       bool "Paravirtualization layer for spinlocks"
+       depends on PARAVIRT && SMP && EXPERIMENTAL
+       ---help---
+         Paravirtualized spinlocks allow a pvops backend to replace the
+         spinlock implementation with something virtualization-friendly
+         (for example, block the virtual CPU rather than spinning).
+
+         Unfortunately the downside is an up to 5% performance hit on
+         native kernels, with various workloads.
+
+         If you are unsure how to answer this question, answer N.
+
 config PARAVIRT_CLOCK
        bool
        default n
index 378e369..a53da00 100644 (file)
@@ -1443,7 +1443,7 @@ u64 _paravirt_ident_64(u64);
 
 #define paravirt_nop   ((void *)_paravirt_nop)
 
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) && defined(CONFIG_PARAVIRT_SPINLOCKS)
 
 static inline int __raw_spin_is_locked(struct raw_spinlock *lock)
 {
index aee103b..02ecb30 100644 (file)
@@ -82,22 +82,22 @@ do {                                                        \
        case 1:                                         \
                asm(op "b %1,"__percpu_arg(0)           \
                    : "+m" (var)                        \
-                   : "ri" ((T__)val));                 \
+                   : "qi" ((T__)(val)));               \
                break;                                  \
        case 2:                                         \
                asm(op "w %1,"__percpu_arg(0)           \
                    : "+m" (var)                        \
-                   : "ri" ((T__)val));                 \
+                   : "ri" ((T__)(val)));               \
                break;                                  \
        case 4:                                         \
                asm(op "l %1,"__percpu_arg(0)           \
                    : "+m" (var)                        \
-                   : "ri" ((T__)val));                 \
+                   : "ri" ((T__)(val)));               \
                break;                                  \
        case 8:                                         \
                asm(op "q %1,"__percpu_arg(0)           \
                    : "+m" (var)                        \
-                   : "re" ((T__)val));                 \
+                   : "re" ((T__)(val)));               \
                break;                                  \
        default: __bad_percpu_size();                   \
        }                                               \
@@ -109,7 +109,7 @@ do {                                                        \
        switch (sizeof(var)) {                          \
        case 1:                                         \
                asm(op "b "__percpu_arg(1)",%0"         \
-                   : "=r" (ret__)                      \
+                   : "=q" (ret__)                      \
                    : "m" (var));                       \
                break;                                  \
        case 2:                                         \
index e304b66..624f133 100644 (file)
@@ -187,14 +187,15 @@ static inline int v8086_mode(struct pt_regs *regs)
 
 /*
  * X86_32 CPUs don't save ss and esp if the CPU is already in kernel mode
- * when it traps.  So regs will be the current sp.
+ * when it traps.  The previous stack will be directly underneath the saved
+ * registers, and 'sp/ss' won't even have been saved. Thus the '&regs->sp'.
  *
  * This is valid only for kernel mode traps.
  */
-static inline unsigned long kernel_trap_sp(struct pt_regs *regs)
+static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
 {
 #ifdef CONFIG_X86_32
-       return (unsigned long)regs;
+       return (unsigned long)(&regs->sp);
 #else
        return regs->sp;
 #endif
index e5e6caf..b7e5db8 100644 (file)
@@ -172,7 +172,7 @@ static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
        return (((tmp >> TICKET_SHIFT) - tmp) & ((1 << TICKET_SHIFT) - 1)) > 1;
 }
 
-#ifndef CONFIG_PARAVIRT
+#ifndef CONFIG_PARAVIRT_SPINLOCKS
 
 static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
 {
@@ -206,7 +206,7 @@ static __always_inline void __raw_spin_lock_flags(raw_spinlock_t *lock,
        __raw_spin_lock(lock);
 }
 
-#endif
+#endif /* CONFIG_PARAVIRT_SPINLOCKS */
 
 static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
 {
index 145cce7..88d1bfc 100644 (file)
@@ -89,7 +89,8 @@ obj-$(CONFIG_DEBUG_NX_TEST)   += test_nx.o
 obj-$(CONFIG_VMI)              += vmi_32.o vmiclock_32.o
 obj-$(CONFIG_KVM_GUEST)                += kvm.o
 obj-$(CONFIG_KVM_CLOCK)                += kvmclock.o
-obj-$(CONFIG_PARAVIRT)         += paravirt.o paravirt_patch_$(BITS).o paravirt-spinlocks.o
+obj-$(CONFIG_PARAVIRT)         += paravirt.o paravirt_patch_$(BITS).o
+obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= paravirt-spinlocks.o
 obj-$(CONFIG_PARAVIRT_CLOCK)   += pvclock.o
 
 obj-$(CONFIG_PCSPKR_PLATFORM)  += pcspeaker.o
index 1c11b81..3029477 100644 (file)
@@ -254,7 +254,7 @@ static int parse_unisys_oem(char *oemptr)
 }
 
 #ifdef CONFIG_ACPI
-static int find_unisys_acpi_oem_table(unsigned long *oem_addr)
+static int __init find_unisys_acpi_oem_table(unsigned long *oem_addr)
 {
        struct acpi_table_header *header = NULL;
        struct es7000_oem_table *table;
@@ -285,7 +285,7 @@ static int find_unisys_acpi_oem_table(unsigned long *oem_addr)
        return 0;
 }
 
-static void unmap_unisys_acpi_oem_table(unsigned long oem_addr)
+static void __init unmap_unisys_acpi_oem_table(unsigned long oem_addr)
 {
        if (!oem_addr)
                return;
@@ -306,7 +306,7 @@ static int es7000_check_dsdt(void)
 static int es7000_acpi_ret;
 
 /* Hook from generic ACPI tables.c */
-static int es7000_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
+static int __init es7000_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 {
        unsigned long oem_addr = 0;
        int check_dsdt;
@@ -717,7 +717,7 @@ struct apic apic_es7000_cluster = {
        .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 };
 
-struct apic apic_es7000 = {
+struct apic __refdata apic_es7000 = {
 
        .name                           = "es7000",
        .probe                          = probe_es7000,
index 0b776c0..d21d4fb 100644 (file)
@@ -275,7 +275,11 @@ static void __init print_mtrr_state(void)
        }
        printk(KERN_DEBUG "MTRR variable ranges %sabled:\n",
               mtrr_state.enabled & 2 ? "en" : "dis");
-       high_width = ((size_or_mask ? ffs(size_or_mask) - 1 : 32) - (32 - PAGE_SHIFT) + 3) / 4;
+       if (size_or_mask & 0xffffffffUL)
+               high_width = ffs(size_or_mask & 0xffffffffUL) - 1;
+       else
+               high_width = ffs(size_or_mask>>32) + 32 - 1;
+       high_width = (high_width - (32 - PAGE_SHIFT) + 3) / 4;
        for (i = 0; i < num_var_ranges; ++i) {
                if (mtrr_state.var_ranges[i].mask_lo & (1 << 11))
                        printk(KERN_DEBUG "  %u base %0*X%05X000 mask %0*X%05X000 %s\n",
index 8e45f44..9faf43b 100644 (file)
@@ -134,7 +134,9 @@ static void *get_call_destination(u8 type)
                .pv_irq_ops = pv_irq_ops,
                .pv_apic_ops = pv_apic_ops,
                .pv_mmu_ops = pv_mmu_ops,
+#ifdef CONFIG_PARAVIRT_SPINLOCKS
                .pv_lock_ops = pv_lock_ops,
+#endif
        };
        return *((void **)&tmpl + type);
 }
index 04df67f..044897b 100644 (file)
@@ -76,9 +76,9 @@ void
 x86_backtrace(struct pt_regs * const regs, unsigned int depth)
 {
        struct frame_head *head = (struct frame_head *)frame_pointer(regs);
-       unsigned long stack = kernel_trap_sp(regs);
 
        if (!user_mode_vm(regs)) {
+               unsigned long stack = kernel_stack_pointer(regs);
                if (depth)
                        dump_trace(NULL, regs, (unsigned long *)stack, 0,
                                   &backtrace_ops, &depth);
index 3b767d0..172438f 100644 (file)
@@ -9,5 +9,6 @@ obj-y           := enlighten.o setup.o multicalls.o mmu.o irq.o \
                        time.o xen-asm.o xen-asm_$(BITS).o \
                        grant-table.o suspend.o
 
-obj-$(CONFIG_SMP)              += smp.o spinlock.o
-obj-$(CONFIG_XEN_DEBUG_FS)     += debugfs.o
\ No newline at end of file
+obj-$(CONFIG_SMP)              += smp.o
+obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o
+obj-$(CONFIG_XEN_DEBUG_FS)     += debugfs.o
index e25a78e..fba55b1 100644 (file)
@@ -42,6 +42,7 @@
 #include <linux/highmem.h>
 #include <linux/debugfs.h>
 #include <linux/bug.h>
+#include <linux/module.h>
 
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
index 2013946..ca6596b 100644 (file)
@@ -62,15 +62,26 @@ void xen_setup_vcpu_info_placement(void);
 #ifdef CONFIG_SMP
 void xen_smp_init(void);
 
-void __init xen_init_spinlocks(void);
-__cpuinit void xen_init_lock_cpu(int cpu);
-void xen_uninit_lock_cpu(int cpu);
-
 extern cpumask_var_t xen_cpu_initialized_map;
 #else
 static inline void xen_smp_init(void) {}
 #endif
 
+#ifdef CONFIG_PARAVIRT_SPINLOCKS
+void __init xen_init_spinlocks(void);
+__cpuinit void xen_init_lock_cpu(int cpu);
+void xen_uninit_lock_cpu(int cpu);
+#else
+static inline void xen_init_spinlocks(void)
+{
+}
+static inline void xen_init_lock_cpu(int cpu)
+{
+}
+static inline void xen_uninit_lock_cpu(int cpu)
+{
+}
+#endif
 
 /* Declare an asm function, along with symbols needed to make it
    inlineable */