diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/Makefile | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/alternative.c | 22 | ||||
| -rw-r--r-- | arch/x86/kernel/entry_32.S | 68 | ||||
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 102 | ||||
| -rw-r--r-- | arch/x86/kernel/ftrace.c | 149 | ||||
| -rw-r--r-- | arch/x86/kernel/i386_ksyms_32.c | 9 | ||||
| -rw-r--r-- | arch/x86/kernel/machine_kexec_32.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/machine_kexec_64.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/process_32.c | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/process_64.c | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/vsyscall_64.c | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/x8664_ksyms_64.c | 11 |
12 files changed, 371 insertions, 15 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 5e618c3b472..739d49acd2f 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 65c7857a90d..2763cb37b55 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 c778e4fa55a..04ea83ccb97 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -1110,6 +1110,74 @@ 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 + +.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 + +.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 + + 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 556a8df522a..fe25e5febca 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -54,6 +54,108 @@ .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 + +.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 + +.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 + + 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 00000000000..bc5cf8d4674 --- /dev/null +++ b/arch/x86/kernel/ftrace.c @@ -0,0 +1,149 @@ +/* + * 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> + +#define CALL_BACK 5 + +/* Long is fine, even if it is only 4 bytes ;-) */ +static long *ftrace_nop; + +union ftrace_code_union { + char code[5]; + 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, 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; + + /* move the IP back to the start of the call */ + ip -= CALL_BACK; + + /* + * 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), "r"(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[5], *new; + int ret; + + ip += CALL_BACK; + + memcpy(old, &ftrace_call, 5); + 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[5], *new; + + /* ip is at the location, but modify code will subtact this */ + ip += CALL_BACK; + + /* + * Replace the mcount stub with a pointer to the + * ip recorder function. + */ + memcpy(old, &mcount_call, 5); + 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[CALL_BACK]; + + return 0; +} + diff --git a/arch/x86/kernel/i386_ksyms_32.c b/arch/x86/kernel/i386_ksyms_32.c index deb43785e92..29999dbb754 100644 --- a/arch/x86/kernel/i386_ksyms_32.c +++ b/arch/x86/kernel/i386_ksyms_32.c @@ -1,7 +1,14 @@ +#include <linux/ftrace.h> #include <linux/module.h> + #include <asm/checksum.h> -#include <asm/desc.h> #include <asm/pgtable.h> +#include <asm/desc.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 d0b234c9fc3..88923fd7a6f 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 576a03db451..1558fdc174f 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 6d5483356e7..61f7481c31d 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 ac54ff56df8..dc534f40c8d 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 61efa2f7d56..4063dfa2a02 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 f6c05d0410f..122885bc5f3 100644 --- a/arch/x86/kernel/x8664_ksyms_64.c +++ b/arch/x86/kernel/x8664_ksyms_64.c @@ -1,15 +1,22 @@ /* Exports for assembly files. All C exports should go in the respective C files. */ +#include <linux/ftrace.h> #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> +#ifdef CONFIG_FTRACE +/* mcount is defined in assembly */ +EXPORT_SYMBOL(mcount); +#endif + EXPORT_SYMBOL(kernel_thread); EXPORT_SYMBOL(__get_user_1); |