[PATCH 1/3] ftrace: Make test_rec_ops_needs_regs() generic

From: Miroslav Benes
Date: Mon Oct 07 2019 - 04:17:21 EST


Function test_rec_ops_needs_regs() tests whether ftrace_ops registered
on a record needs saved regs. That is, it tests for
FTRACE_OPS_FL_SAVE_REGS being set.

The same logic will be reused for newly introduced
FTRACE_OPS_FL_PERMANENT flag, so make the function generic.

Signed-off-by: Miroslav Benes <mbenes@xxxxxxx>
---
kernel/trace/ftrace.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 62a50bf399d6..a37c1127599c 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1602,24 +1602,24 @@ int ftrace_text_reserved(const void *start, const void *end)
return (int)!!ret;
}

-/* Test if ops registered to this rec needs regs */
-static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
+/* Test if ops registered to this rec needs to have a specified flag set */
+static bool test_rec_ops_needs_flag(struct dyn_ftrace *rec, int flag)
{
struct ftrace_ops *ops;
- bool keep_regs = false;
+ bool keep_flag = false;

for (ops = ftrace_ops_list;
ops != &ftrace_list_end; ops = ops->next) {
/* pass rec in as regs to have non-NULL val */
if (ftrace_ops_test(ops, rec->ip, rec)) {
- if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
- keep_regs = true;
+ if (ops->flags & flag) {
+ keep_flag = true;
break;
}
}
}

- return keep_regs;
+ return keep_flag;
}

static struct ftrace_ops *
@@ -1750,7 +1750,8 @@ static bool __ftrace_hash_rec_update(struct ftrace_ops *ops,
if (ftrace_rec_count(rec) > 0 &&
rec->flags & FTRACE_FL_REGS &&
ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
- if (!test_rec_ops_needs_regs(rec))
+ if (!test_rec_ops_needs_flag(rec,
+ FTRACE_OPS_FL_SAVE_REGS))
rec->flags &= ~FTRACE_FL_REGS;
}

--
2.23.0