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-rw-r--r--arch/x86/kernel/Makefile8
-rw-r--r--arch/x86/kernel/alternative.c22
-rw-r--r--arch/x86/kernel/entry_32.S72
-rw-r--r--arch/x86/kernel/entry_64.S106
-rw-r--r--arch/x86/kernel/ftrace.c141
-rw-r--r--arch/x86/kernel/i386_ksyms_32.c9
-rw-r--r--arch/x86/kernel/machine_kexec_32.c4
-rw-r--r--arch/x86/kernel/machine_kexec_64.c4
-rw-r--r--arch/x86/kernel/process_32.c3
-rw-r--r--arch/x86/kernel/process_64.c3
-rw-r--r--arch/x86/kernel/vsyscall_64.c3
-rw-r--r--arch/x86/kernel/x8664_ksyms_64.c11
12 files changed, 371 insertions, 15 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 77807d4769c9..5ff67208d4ae 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -6,6 +6,13 @@ extra-y := head_$(BITS).o head$(BITS).o init_task.o vmlinux.lds
CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE)
+ifdef CONFIG_FTRACE
+# Do not profile debug utilities
+CFLAGS_REMOVE_tsc_64.o = -pg
+CFLAGS_REMOVE_tsc_32.o = -pg
+CFLAGS_REMOVE_rtc.o = -pg
+endif
+
#
# vsyscalls (which work on the user stack) should have
# no stack-protector checks:
@@ -56,6 +63,7 @@ obj-$(CONFIG_X86_MPPARSE) += mpparse.o
obj-$(CONFIG_X86_LOCAL_APIC) += apic_$(BITS).o nmi_$(BITS).o
obj-$(CONFIG_X86_IO_APIC) += io_apic_$(BITS).o
obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o
+obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o
obj-$(CONFIG_KEXEC) += relocate_kernel_$(BITS).o crash.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 65c7857a90dd..2763cb37b553 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -1,6 +1,6 @@
#include <linux/module.h>
#include <linux/sched.h>
-#include <linux/spinlock.h>
+#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/kprobes.h>
#include <linux/mm.h>
@@ -143,7 +143,7 @@ static const unsigned char *const p6_nops[ASM_NOP_MAX+1] = {
#ifdef CONFIG_X86_64
extern char __vsyscall_0;
-static inline const unsigned char*const * find_nop_table(void)
+const unsigned char *const *find_nop_table(void)
{
return boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
boot_cpu_data.x86 < 6 ? k8_nops : p6_nops;
@@ -162,7 +162,7 @@ static const struct nop {
{ -1, NULL }
};
-static const unsigned char*const * find_nop_table(void)
+const unsigned char *const *find_nop_table(void)
{
const unsigned char *const *noptable = intel_nops;
int i;
@@ -279,7 +279,7 @@ struct smp_alt_module {
struct list_head next;
};
static LIST_HEAD(smp_alt_modules);
-static DEFINE_SPINLOCK(smp_alt);
+static DEFINE_MUTEX(smp_alt);
static int smp_mode = 1; /* protected by smp_alt */
void alternatives_smp_module_add(struct module *mod, char *name,
@@ -312,12 +312,12 @@ void alternatives_smp_module_add(struct module *mod, char *name,
__func__, smp->locks, smp->locks_end,
smp->text, smp->text_end, smp->name);
- spin_lock(&smp_alt);
+ mutex_lock(&smp_alt);
list_add_tail(&smp->next, &smp_alt_modules);
if (boot_cpu_has(X86_FEATURE_UP))
alternatives_smp_unlock(smp->locks, smp->locks_end,
smp->text, smp->text_end);
- spin_unlock(&smp_alt);
+ mutex_unlock(&smp_alt);
}
void alternatives_smp_module_del(struct module *mod)
@@ -327,17 +327,17 @@ void alternatives_smp_module_del(struct module *mod)
if (smp_alt_once || noreplace_smp)
return;
- spin_lock(&smp_alt);
+ mutex_lock(&smp_alt);
list_for_each_entry(item, &smp_alt_modules, next) {
if (mod != item->mod)
continue;
list_del(&item->next);
- spin_unlock(&smp_alt);
+ mutex_unlock(&smp_alt);
DPRINTK("%s: %s\n", __func__, item->name);
kfree(item);
return;
}
- spin_unlock(&smp_alt);
+ mutex_unlock(&smp_alt);
}
void alternatives_smp_switch(int smp)
@@ -359,7 +359,7 @@ void alternatives_smp_switch(int smp)
return;
BUG_ON(!smp && (num_online_cpus() > 1));
- spin_lock(&smp_alt);
+ mutex_lock(&smp_alt);
/*
* Avoid unnecessary switches because it forces JIT based VMs to
@@ -383,7 +383,7 @@ void alternatives_smp_switch(int smp)
mod->text, mod->text_end);
}
smp_mode = smp;
- spin_unlock(&smp_alt);
+ mutex_unlock(&smp_alt);
}
#endif
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index c778e4fa55a2..95e6bbe3665e 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -51,6 +51,7 @@
#include <asm/percpu.h>
#include <asm/dwarf2.h>
#include <asm/processor-flags.h>
+#include <asm/ftrace.h>
#include "irq_vectors.h"
/*
@@ -1110,6 +1111,77 @@ ENDPROC(xen_failsafe_callback)
#endif /* CONFIG_XEN */
+#ifdef CONFIG_FTRACE
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+ENTRY(mcount)
+ pushl %eax
+ pushl %ecx
+ pushl %edx
+ movl 0xc(%esp), %eax
+ subl $MCOUNT_INSN_SIZE, %eax
+
+.globl mcount_call
+mcount_call:
+ call ftrace_stub
+
+ popl %edx
+ popl %ecx
+ popl %eax
+
+ ret
+END(mcount)
+
+ENTRY(ftrace_caller)
+ pushl %eax
+ pushl %ecx
+ pushl %edx
+ movl 0xc(%esp), %eax
+ movl 0x4(%ebp), %edx
+ subl $MCOUNT_INSN_SIZE, %eax
+
+.globl ftrace_call
+ftrace_call:
+ call ftrace_stub
+
+ popl %edx
+ popl %ecx
+ popl %eax
+
+.globl ftrace_stub
+ftrace_stub:
+ ret
+END(ftrace_caller)
+
+#else /* ! CONFIG_DYNAMIC_FTRACE */
+
+ENTRY(mcount)
+ cmpl $ftrace_stub, ftrace_trace_function
+ jnz trace
+.globl ftrace_stub
+ftrace_stub:
+ ret
+
+ /* taken from glibc */
+trace:
+ pushl %eax
+ pushl %ecx
+ pushl %edx
+ movl 0xc(%esp), %eax
+ movl 0x4(%ebp), %edx
+ subl $MCOUNT_INSN_SIZE, %eax
+
+ call *ftrace_trace_function
+
+ popl %edx
+ popl %ecx
+ popl %eax
+
+ jmp ftrace_stub
+END(mcount)
+#endif /* CONFIG_DYNAMIC_FTRACE */
+#endif /* CONFIG_FTRACE */
+
.section .rodata,"a"
#include "syscall_table_32.S"
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 556a8df522a7..b0f7308f78a6 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -51,9 +51,115 @@
#include <asm/page.h>
#include <asm/irqflags.h>
#include <asm/paravirt.h>
+#include <asm/ftrace.h>
.code64
+#ifdef CONFIG_FTRACE
+#ifdef CONFIG_DYNAMIC_FTRACE
+ENTRY(mcount)
+
+ subq $0x38, %rsp
+ movq %rax, (%rsp)
+ movq %rcx, 8(%rsp)
+ movq %rdx, 16(%rsp)
+ movq %rsi, 24(%rsp)
+ movq %rdi, 32(%rsp)
+ movq %r8, 40(%rsp)
+ movq %r9, 48(%rsp)
+
+ movq 0x38(%rsp), %rdi
+ subq $MCOUNT_INSN_SIZE, %rdi
+
+.globl mcount_call
+mcount_call:
+ call ftrace_stub
+
+ movq 48(%rsp), %r9
+ movq 40(%rsp), %r8
+ movq 32(%rsp), %rdi
+ movq 24(%rsp), %rsi
+ movq 16(%rsp), %rdx
+ movq 8(%rsp), %rcx
+ movq (%rsp), %rax
+ addq $0x38, %rsp
+
+ retq
+END(mcount)
+
+ENTRY(ftrace_caller)
+
+ /* taken from glibc */
+ subq $0x38, %rsp
+ movq %rax, (%rsp)
+ movq %rcx, 8(%rsp)
+ movq %rdx, 16(%rsp)
+ movq %rsi, 24(%rsp)
+ movq %rdi, 32(%rsp)
+ movq %r8, 40(%rsp)
+ movq %r9, 48(%rsp)
+
+ movq 0x38(%rsp), %rdi
+ movq 8(%rbp), %rsi
+ subq $MCOUNT_INSN_SIZE, %rdi
+
+.globl ftrace_call
+ftrace_call:
+ call ftrace_stub
+
+ movq 48(%rsp), %r9
+ movq 40(%rsp), %r8
+ movq 32(%rsp), %rdi
+ movq 24(%rsp), %rsi
+ movq 16(%rsp), %rdx
+ movq 8(%rsp), %rcx
+ movq (%rsp), %rax
+ addq $0x38, %rsp
+
+.globl ftrace_stub
+ftrace_stub:
+ retq
+END(ftrace_caller)
+
+#else /* ! CONFIG_DYNAMIC_FTRACE */
+ENTRY(mcount)
+ cmpq $ftrace_stub, ftrace_trace_function
+ jnz trace
+.globl ftrace_stub
+ftrace_stub:
+ retq
+
+trace:
+ /* taken from glibc */
+ subq $0x38, %rsp
+ movq %rax, (%rsp)
+ movq %rcx, 8(%rsp)
+ movq %rdx, 16(%rsp)
+ movq %rsi, 24(%rsp)
+ movq %rdi, 32(%rsp)
+ movq %r8, 40(%rsp)
+ movq %r9, 48(%rsp)
+
+ movq 0x38(%rsp), %rdi
+ movq 8(%rbp), %rsi
+ subq $MCOUNT_INSN_SIZE, %rdi
+
+ call *ftrace_trace_function
+
+ movq 48(%rsp), %r9
+ movq 40(%rsp), %r8
+ movq 32(%rsp), %rdi
+ movq 24(%rsp), %rsi
+ movq 16(%rsp), %rdx
+ movq 8(%rsp), %rcx
+ movq (%rsp), %rax
+ addq $0x38, %rsp
+
+ jmp ftrace_stub
+END(mcount)
+#endif /* CONFIG_DYNAMIC_FTRACE */
+#endif /* CONFIG_FTRACE */
+
#ifndef CONFIG_PREEMPT
#define retint_kernel retint_restore_args
#endif
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
new file mode 100644
index 000000000000..ab115cd15fdf
--- /dev/null
+++ b/arch/x86/kernel/ftrace.c
@@ -0,0 +1,141 @@
+/*
+ * Code for replacing ftrace calls with jumps.
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ *
+ * Thanks goes to Ingo Molnar, for suggesting the idea.
+ * Mathieu Desnoyers, for suggesting postponing the modifications.
+ * Arjan van de Ven, for keeping me straight, and explaining to me
+ * the dangers of modifying code on the run.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/hardirq.h>
+#include <linux/ftrace.h>
+#include <linux/percpu.h>
+#include <linux/init.h>
+#include <linux/list.h>
+
+#include <asm/alternative.h>
+#include <asm/ftrace.h>
+
+
+/* Long is fine, even if it is only 4 bytes ;-) */
+static long *ftrace_nop;
+
+union ftrace_code_union {
+ char code[MCOUNT_INSN_SIZE];
+ struct {
+ char e8;
+ int offset;
+ } __attribute__((packed));
+};
+
+
+static int notrace ftrace_calc_offset(long ip, long addr)
+{
+ return (int)(addr - ip);
+}
+
+notrace unsigned char *ftrace_nop_replace(void)
+{
+ return (char *)ftrace_nop;
+}
+
+notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+{
+ static union ftrace_code_union calc;
+
+ calc.e8 = 0xe8;
+ calc.offset = ftrace_calc_offset(ip + MCOUNT_INSN_SIZE, addr);
+
+ /*
+ * No locking needed, this must be called via kstop_machine
+ * which in essence is like running on a uniprocessor machine.
+ */
+ return calc.code;
+}
+
+notrace int
+ftrace_modify_code(unsigned long ip, unsigned char *old_code,
+ unsigned char *new_code)
+{
+ unsigned replaced;
+ unsigned old = *(unsigned *)old_code; /* 4 bytes */
+ unsigned new = *(unsigned *)new_code; /* 4 bytes */
+ unsigned char newch = new_code[4];
+ int faulted = 0;
+
+ /*
+ * Note: Due to modules and __init, code can
+ * disappear and change, we need to protect against faulting
+ * as well as code changing.
+ *
+ * No real locking needed, this code is run through
+ * kstop_machine.
+ */
+ asm volatile (
+ "1: lock\n"
+ " cmpxchg %3, (%2)\n"
+ " jnz 2f\n"
+ " movb %b4, 4(%2)\n"
+ "2:\n"
+ ".section .fixup, \"ax\"\n"
+ "3: movl $1, %0\n"
+ " jmp 2b\n"
+ ".previous\n"
+ _ASM_EXTABLE(1b, 3b)
+ : "=r"(faulted), "=a"(replaced)
+ : "r"(ip), "r"(new), "c"(newch),
+ "0"(faulted), "a"(old)
+ : "memory");
+ sync_core();
+
+ if (replaced != old && replaced != new)
+ faulted = 2;
+
+ return faulted;
+}
+
+notrace int ftrace_update_ftrace_func(ftrace_func_t func)
+{
+ unsigned long ip = (unsigned long)(&ftrace_call);
+ unsigned char old[MCOUNT_INSN_SIZE], *new;
+ int ret;
+
+ memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE);
+ new = ftrace_call_replace(ip, (unsigned long)func);
+ ret = ftrace_modify_code(ip, old, new);
+
+ return ret;
+}
+
+notrace int ftrace_mcount_set(unsigned long *data)
+{
+ unsigned long ip = (long)(&mcount_call);
+ unsigned long *addr = data;
+ unsigned char old[MCOUNT_INSN_SIZE], *new;
+
+ /*
+ * Replace the mcount stub with a pointer to the
+ * ip recorder function.
+ */
+ memcpy(old, &mcount_call, MCOUNT_INSN_SIZE);
+ new = ftrace_call_replace(ip, *addr);
+ *addr = ftrace_modify_code(ip, old, new);
+
+ return 0;
+}
+
+int __init ftrace_dyn_arch_init(void *data)
+{
+ const unsigned char *const *noptable = find_nop_table();
+
+ /* This is running in kstop_machine */
+
+ ftrace_mcount_set(data);
+
+ ftrace_nop = (unsigned long *)noptable[MCOUNT_INSN_SIZE];
+
+ return 0;
+}
diff --git a/arch/x86/kernel/i386_ksyms_32.c b/arch/x86/kernel/i386_ksyms_32.c
index deb43785e923..dd7ebee446af 100644
--- a/arch/x86/kernel/i386_ksyms_32.c
+++ b/arch/x86/kernel/i386_ksyms_32.c
@@ -1,7 +1,14 @@
#include <linux/module.h>
+
#include <asm/checksum.h>
-#include <asm/desc.h>
#include <asm/pgtable.h>
+#include <asm/desc.h>
+#include <asm/ftrace.h>
+
+#ifdef CONFIG_FTRACE
+/* mcount is defined in assembly */
+EXPORT_SYMBOL(mcount);
+#endif
/* Networking helper routines. */
EXPORT_SYMBOL(csum_partial_copy_generic);
diff --git a/arch/x86/kernel/machine_kexec_32.c b/arch/x86/kernel/machine_kexec_32.c
index d0b234c9fc31..88923fd7a6fc 100644
--- a/arch/x86/kernel/machine_kexec_32.c
+++ b/arch/x86/kernel/machine_kexec_32.c
@@ -11,6 +11,8 @@
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/numa.h>
+#include <linux/ftrace.h>
+
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
@@ -107,6 +109,8 @@ NORET_TYPE void machine_kexec(struct kimage *image)
unsigned long page_list[PAGES_NR];
void *control_page;
+ tracer_disable();
+
/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 576a03db4511..1558fdc174f9 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -11,6 +11,8 @@
#include <linux/string.h>
#include <linux/reboot.h>
#include <linux/numa.h>
+#include <linux/ftrace.h>
+
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
@@ -184,6 +186,8 @@ NORET_TYPE void machine_kexec(struct kimage *image)
unsigned long page_list[PAGES_NR];
void *control_page;
+ tracer_disable();
+
/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index e2db9ac5c61c..347a7aba8b16 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -185,7 +185,10 @@ void cpu_idle(void)
local_irq_disable();
__get_cpu_var(irq_stat).idle_timestamp = jiffies;
+ /* Don't trace irqs off for idle */
+ stop_critical_timings();
idle();
+ start_critical_timings();
}
tick_nohz_restart_sched_tick();
preempt_enable_no_resched();
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index c6eb5c91e5f6..ea090e6cfe39 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -165,7 +165,10 @@ void cpu_idle(void)
*/
local_irq_disable();
enter_idle();
+ /* Don't trace irqs off for idle */
+ stop_critical_timings();
idle();
+ start_critical_timings();
/* In many cases the interrupt that ended idle
has already called exit_idle. But some idle
loops can be woken up without interrupt. */
diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c
index 61efa2f7d564..4063dfa2a02d 100644
--- a/arch/x86/kernel/vsyscall_64.c
+++ b/arch/x86/kernel/vsyscall_64.c
@@ -42,7 +42,8 @@
#include <asm/topology.h>
#include <asm/vgtod.h>
-#define __vsyscall(nr) __attribute__ ((unused,__section__(".vsyscall_" #nr)))
+#define __vsyscall(nr) \
+ __attribute__ ((unused, __section__(".vsyscall_" #nr))) notrace
#define __syscall_clobber "r11","cx","memory"
/*
diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c
index f6c05d0410fb..16ff4bf418d9 100644
--- a/arch/x86/kernel/x8664_ksyms_64.c
+++ b/arch/x86/kernel/x8664_ksyms_64.c
@@ -2,13 +2,20 @@
All C exports should go in the respective C files. */
#include <linux/module.h>
-#include <net/checksum.h>
#include <linux/smp.h>
+#include <net/checksum.h>
+
#include <asm/processor.h>
-#include <asm/uaccess.h>
#include <asm/pgtable.h>
+#include <asm/uaccess.h>
#include <asm/desc.h>
+#include <asm/ftrace.h>
+
+#ifdef CONFIG_FTRACE
+/* mcount is defined in assembly */
+EXPORT_SYMBOL(mcount);
+#endif
EXPORT_SYMBOL(kernel_thread);