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Diffstat (limited to 'arch/x86/kernel/ftrace.c')
-rw-r--r--arch/x86/kernel/ftrace.c85
1 files changed, 41 insertions, 44 deletions
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 70139d9d2e01..252e82bcfd2f 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -25,6 +25,7 @@
#include <linux/memory.h>
#include <linux/vmalloc.h>
#include <linux/set_memory.h>
+#include <linux/execmem.h>
#include <trace/syscall.h>
@@ -54,10 +55,10 @@ void ftrace_arch_code_modify_post_process(void)
{
/*
* ftrace_make_{call,nop}() may be called during
- * module load, and we need to finish the text_poke_queue()
+ * module load, and we need to finish the smp_text_poke_batch_add()
* that they do, here.
*/
- text_poke_finish();
+ smp_text_poke_batch_finish();
ftrace_poke_late = 0;
mutex_unlock(&text_mutex);
}
@@ -118,7 +119,7 @@ ftrace_modify_code_direct(unsigned long ip, const char *old_code,
/* replace the text with the new text */
if (ftrace_poke_late)
- text_poke_queue((void *)ip, new_code, MCOUNT_INSN_SIZE, NULL);
+ smp_text_poke_batch_add((void *)ip, new_code, MCOUNT_INSN_SIZE, NULL);
else
text_poke_early((void *)ip, new_code, MCOUNT_INSN_SIZE);
return 0;
@@ -185,11 +186,11 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
ip = (unsigned long)(&ftrace_call);
new = ftrace_call_replace(ip, (unsigned long)func);
- text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+ smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
ip = (unsigned long)(&ftrace_regs_call);
new = ftrace_call_replace(ip, (unsigned long)func);
- text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+ smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
return 0;
}
@@ -246,10 +247,10 @@ void ftrace_replace_code(int enable)
break;
}
- text_poke_queue((void *)rec->ip, new, MCOUNT_INSN_SIZE, NULL);
+ smp_text_poke_batch_add((void *)rec->ip, new, MCOUNT_INSN_SIZE, NULL);
ftrace_update_record(rec, enable);
}
- text_poke_finish();
+ smp_text_poke_batch_finish();
}
void arch_ftrace_update_code(int command)
@@ -260,25 +261,14 @@ void arch_ftrace_update_code(int command)
/* Currently only x86_64 supports dynamic trampolines */
#ifdef CONFIG_X86_64
-#ifdef CONFIG_MODULES
-#include <linux/moduleloader.h>
-/* Module allocation simplifies allocating memory for code */
static inline void *alloc_tramp(unsigned long size)
{
- return module_alloc(size);
+ return execmem_alloc(EXECMEM_FTRACE, size);
}
static inline void tramp_free(void *tramp)
{
- module_memfree(tramp);
+ execmem_free(tramp);
}
-#else
-/* Trampolines can only be created if modules are supported */
-static inline void *alloc_tramp(unsigned long size)
-{
- return NULL;
-}
-static inline void tramp_free(void *tramp) { }
-#endif
/* Defined as markers to the end of the ftrace default trampolines */
extern void ftrace_regs_caller_end(void);
@@ -364,7 +354,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
goto fail;
ip = trampoline + size;
- if (cpu_feature_enabled(X86_FEATURE_RETHUNK))
+ if (cpu_wants_rethunk_at(ip))
__text_gen_insn(ip, JMP32_INSN_OPCODE, ip, x86_return_thunk, JMP32_INSN_SIZE);
else
memcpy(ip, retq, sizeof(retq));
@@ -502,7 +492,7 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops)
mutex_lock(&text_mutex);
/* Do a safe modify in case the trampoline is executing */
new = ftrace_call_replace(ip, (unsigned long)func);
- text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+ smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
mutex_unlock(&text_mutex);
}
@@ -596,7 +586,7 @@ static int ftrace_mod_jmp(unsigned long ip, void *func)
const char *new;
new = ftrace_jmp_replace(ip, (unsigned long)func);
- text_poke_bp((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
+ smp_text_poke_single((void *)ip, new, MCOUNT_INSN_SIZE, NULL);
return 0;
}
@@ -615,16 +605,8 @@ int ftrace_disable_ftrace_graph_caller(void)
}
#endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */
-/*
- * Hook the return address and push it in the stack of return addrs
- * in current thread info.
- */
-void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
- unsigned long frame_pointer)
+static inline bool skip_ftrace_return(void)
{
- unsigned long return_hooker = (unsigned long)&return_to_handler;
- int bit;
-
/*
* When resuming from suspend-to-ram, this function can be indirectly
* called from early CPU startup code while the CPU is in real mode,
@@ -634,33 +616,48 @@ void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
* This check isn't as accurate as virt_addr_valid(), but it should be
* good enough for this purpose, and it's fast.
*/
- if (unlikely((long)__builtin_frame_address(0) >= 0))
- return;
+ if ((long)__builtin_frame_address(0) >= 0)
+ return true;
- if (unlikely(ftrace_graph_is_dead()))
- return;
+ if (ftrace_graph_is_dead())
+ return true;
- if (unlikely(atomic_read(&current->tracing_graph_pause)))
- return;
+ if (atomic_read(&current->tracing_graph_pause))
+ return true;
+ return false;
+}
- bit = ftrace_test_recursion_trylock(ip, *parent);
- if (bit < 0)
+/*
+ * Hook the return address and push it in the stack of return addrs
+ * in current thread info.
+ */
+void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
+ unsigned long frame_pointer)
+{
+ unsigned long return_hooker = (unsigned long)&return_to_handler;
+
+ if (unlikely(skip_ftrace_return()))
return;
if (!function_graph_enter(*parent, ip, frame_pointer, parent))
*parent = return_hooker;
-
- ftrace_test_recursion_unlock(bit);
}
#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct ftrace_regs *fregs)
{
- struct pt_regs *regs = &fregs->regs;
+ struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
unsigned long *stack = (unsigned long *)kernel_stack_pointer(regs);
+ unsigned long return_hooker = (unsigned long)&return_to_handler;
+ unsigned long *parent = (unsigned long *)stack;
- prepare_ftrace_return(ip, (unsigned long *)stack, 0);
+ if (unlikely(skip_ftrace_return()))
+ return;
+
+
+ if (!function_graph_enter_regs(*parent, ip, 0, parent, fregs))
+ *parent = return_hooker;
}
#endif