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Diffstat (limited to 'arch/powerpc/kernel/ftrace.c')
-rw-r--r--arch/powerpc/kernel/ftrace.c92
1 files changed, 67 insertions, 25 deletions
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index bf99cfa6bbf..1fb78561096 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -63,11 +63,9 @@ ftrace_modify_code(unsigned long ip, unsigned int old, unsigned int new)
return -EINVAL;
/* replace the text with the new text */
- if (probe_kernel_write((void *)ip, &new, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, new))
return -EPERM;
- flush_icache_range(ip, ip + 8);
-
return 0;
}
@@ -212,12 +210,9 @@ __ftrace_make_nop(struct module *mod,
*/
op = 0x48000008; /* b +8 */
- if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, op))
return -EPERM;
-
- flush_icache_range(ip, ip + 8);
-
return 0;
}
@@ -245,9 +240,9 @@ __ftrace_make_nop(struct module *mod,
/*
* On PPC32 the trampoline looks like:
- * 0x3d, 0x60, 0x00, 0x00 lis r11,sym@ha
- * 0x39, 0x6b, 0x00, 0x00 addi r11,r11,sym@l
- * 0x7d, 0x69, 0x03, 0xa6 mtctr r11
+ * 0x3d, 0x80, 0x00, 0x00 lis r12,sym@ha
+ * 0x39, 0x8c, 0x00, 0x00 addi r12,r12,sym@l
+ * 0x7d, 0x89, 0x03, 0xa6 mtctr r12
* 0x4e, 0x80, 0x04, 0x20 bctr
*/
@@ -262,9 +257,9 @@ __ftrace_make_nop(struct module *mod,
pr_devel(" %08x %08x ", jmp[0], jmp[1]);
/* verify that this is what we expect it to be */
- if (((jmp[0] & 0xffff0000) != 0x3d600000) ||
- ((jmp[1] & 0xffff0000) != 0x396b0000) ||
- (jmp[2] != 0x7d6903a6) ||
+ if (((jmp[0] & 0xffff0000) != 0x3d800000) ||
+ ((jmp[1] & 0xffff0000) != 0x398c0000) ||
+ (jmp[2] != 0x7d8903a6) ||
(jmp[3] != 0x4e800420)) {
printk(KERN_ERR "Not a trampoline\n");
return -EINVAL;
@@ -286,11 +281,9 @@ __ftrace_make_nop(struct module *mod,
op = PPC_INST_NOP;
- if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, op))
return -EPERM;
- flush_icache_range(ip, ip + 8);
-
return 0;
}
#endif /* PPC64 */
@@ -426,11 +419,9 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
pr_devel("write to %lx\n", rec->ip);
- if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, op))
return -EPERM;
- flush_icache_range(ip, ip + 8);
-
return 0;
}
#endif /* CONFIG_PPC64 */
@@ -484,6 +475,58 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
return ret;
}
+static int __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
+{
+ unsigned long ftrace_addr = (unsigned long)FTRACE_ADDR;
+ int ret;
+
+ ret = ftrace_update_record(rec, enable);
+
+ switch (ret) {
+ case FTRACE_UPDATE_IGNORE:
+ return 0;
+ case FTRACE_UPDATE_MAKE_CALL:
+ return ftrace_make_call(rec, ftrace_addr);
+ case FTRACE_UPDATE_MAKE_NOP:
+ return ftrace_make_nop(NULL, rec, ftrace_addr);
+ }
+
+ return 0;
+}
+
+void ftrace_replace_code(int enable)
+{
+ struct ftrace_rec_iter *iter;
+ struct dyn_ftrace *rec;
+ int ret;
+
+ for (iter = ftrace_rec_iter_start(); iter;
+ iter = ftrace_rec_iter_next(iter)) {
+ rec = ftrace_rec_iter_record(iter);
+ ret = __ftrace_replace_code(rec, enable);
+ if (ret) {
+ ftrace_bug(ret, rec->ip);
+ return;
+ }
+ }
+}
+
+void arch_ftrace_update_code(int command)
+{
+ if (command & FTRACE_UPDATE_CALLS)
+ ftrace_replace_code(1);
+ else if (command & FTRACE_DISABLE_CALLS)
+ ftrace_replace_code(0);
+
+ if (command & FTRACE_UPDATE_TRACE_FUNC)
+ ftrace_update_ftrace_func(ftrace_trace_function);
+
+ if (command & FTRACE_START_FUNC_RET)
+ ftrace_enable_ftrace_graph_caller();
+ else if (command & FTRACE_STOP_FUNC_RET)
+ ftrace_disable_ftrace_graph_caller();
+}
+
int __init ftrace_dyn_arch_init(void *data)
{
/* caller expects data to be zero */
@@ -587,18 +630,17 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
return;
}
- if (ftrace_push_return_trace(old, self_addr, &trace.depth, 0) == -EBUSY) {
- *parent = old;
- return;
- }
-
trace.func = self_addr;
+ trace.depth = current->curr_ret_stack + 1;
/* Only trace if the calling function expects to */
if (!ftrace_graph_entry(&trace)) {
- current->curr_ret_stack--;
*parent = old;
+ return;
}
+
+ if (ftrace_push_return_trace(old, self_addr, &trace.depth, 0) == -EBUSY)
+ *parent = old;
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */