The following commit has been merged into the perf/core branch of tip:
Commit-ID: 5578534e4b92350995a20068f2e6ea3186c62d7f
Gitweb: https://git.kernel.org/tip/5578534e4b92350995a20068f2e6ea3186c62d7f
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Tue, 23 Sep 2025 13:04:09 +02:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 29 Oct 2025 10:29:57 +01:00
unwind: Simplify unwind_user_next_fp() alignment check
2^log_2(n) == n
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://patch.msgid.link/20250924080119.497867836@infradead.org
---
kernel/unwind/user.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/kernel/unwind/user.c b/kernel/unwind/user.c
index 97a8415..9dcde79 100644
--- a/kernel/unwind/user.c
+++ b/kernel/unwind/user.c
@@ -19,7 +19,6 @@ static int unwind_user_next_fp(struct unwind_user_state *state)
{
const struct unwind_user_frame *frame = &fp_frame;
unsigned long cfa, fp, ra;
- unsigned int shift;
if (frame->use_fp) {
if (state->fp < state->sp)
@@ -37,8 +36,7 @@ static int unwind_user_next_fp(struct unwind_user_state *state)
return -EINVAL;
/* Make sure that the address is word aligned */
- shift = sizeof(long) == 4 ? 2 : 3;
- if (cfa & ((1 << shift) - 1))
+ if (cfa & (sizeof(long) - 1))
return -EINVAL;
/* Find the Return Address (RA) */