summaryrefslogtreecommitdiff
path: root/arch/mips
diff options
context:
space:
mode:
authorSteven Rostedt (VMware) <rostedt@goodmis.org>2018-11-18 17:25:18 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-12-05 19:32:10 +0100
commit35aa93cbb04c33a6a771c47e6c04c401615f0dd4 (patch)
treedd059b8646ed53c8ff61621920577a7a7b12f7c0 /arch/mips
parentbdfd01cfd1e7306e9488cf6cbb0766945d202c1f (diff)
MIPS: function_graph: Simplify with function_graph_enter()
commit 8712b27c5723c26400a2b350faf1d6d9fd7ffaad upstream. The function_graph_enter() function does the work of calling the function graph hook function and the management of the shadow stack, simplifying the work done in the architecture dependent prepare_ftrace_return(). Have MIPS use the new code, and remove the shadow stack management as well as having to set up the trace structure. This is needed to prepare for a fix of a design bug on how the curr_ret_stack is used. Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: linux-mips@linux-mips.org Cc: stable@kernel.org Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback") Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/mips')
-rw-r--r--arch/mips/kernel/ftrace.c14
1 files changed, 2 insertions, 12 deletions
diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c
index 7f3dfdbc3657..b122cbb4aad1 100644
--- a/arch/mips/kernel/ftrace.c
+++ b/arch/mips/kernel/ftrace.c
@@ -322,7 +322,6 @@ void prepare_ftrace_return(unsigned long *parent_ra_addr, unsigned long self_ra,
unsigned long fp)
{
unsigned long old_parent_ra;
- struct ftrace_graph_ent trace;
unsigned long return_hooker = (unsigned long)
&return_to_handler;
int faulted, insns;
@@ -369,12 +368,6 @@ void prepare_ftrace_return(unsigned long *parent_ra_addr, unsigned long self_ra,
if (unlikely(faulted))
goto out;
- if (ftrace_push_return_trace(old_parent_ra, self_ra, &trace.depth, fp,
- NULL) == -EBUSY) {
- *parent_ra_addr = old_parent_ra;
- return;
- }
-
/*
* Get the recorded ip of the current mcount calling site in the
* __mcount_loc section, which will be used to filter the function
@@ -382,13 +375,10 @@ void prepare_ftrace_return(unsigned long *parent_ra_addr, unsigned long self_ra,
*/
insns = core_kernel_text(self_ra) ? 2 : MCOUNT_OFFSET_INSNS + 1;
- trace.func = self_ra - (MCOUNT_INSN_SIZE * insns);
+ self_ra -= (MCOUNT_INSN_SIZE * insns);
- /* Only trace if the calling function expects to */
- if (!ftrace_graph_entry(&trace)) {
- current->curr_ret_stack--;
+ if (function_graph_enter(old_parent_ra, self_ra, fp, NULL))
*parent_ra_addr = old_parent_ra;
- }
return;
out:
ftrace_graph_stop();