From: Josh Poimboeuf <jpoimboe@kernel.org>
Date: Wed, 20 Aug 2025 18:03:42 +0000 (-0400)
Subject: perf: Simplify get_perf_callchain() user logic
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d77e3319e31098a6cb97b7ce4e71ba676e327fd7;p=thirdparty%2Fkernel%2Fstable.git

perf: Simplify get_perf_callchain() user logic

Simplify the get_perf_callchain() user logic a bit.  task_pt_regs()
should never be NULL.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250820180428.760066227@kernel.org
---

diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index 5982d18f169bd..808c0d7a31faf 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -247,21 +247,19 @@ get_perf_callchain(struct pt_regs *regs, bool kernel, bool user,
 	if (user && !crosstask) {
 		if (!user_mode(regs)) {
 			if (current->flags & (PF_KTHREAD | PF_USER_WORKER))
-				regs = NULL;
-			else
-				regs = task_pt_regs(current);
+				goto exit_put;
+			regs = task_pt_regs(current);
 		}
 
-		if (regs) {
-			if (add_mark)
-				perf_callchain_store_context(&ctx, PERF_CONTEXT_USER);
+		if (add_mark)
+			perf_callchain_store_context(&ctx, PERF_CONTEXT_USER);
 
-			start_entry_idx = entry->nr;
-			perf_callchain_user(&ctx, regs);
-			fixup_uretprobe_trampoline_entries(entry, start_entry_idx);
-		}
+		start_entry_idx = entry->nr;
+		perf_callchain_user(&ctx, regs);
+		fixup_uretprobe_trampoline_entries(entry, start_entry_idx);
 	}
 
+exit_put:
 	put_callchain_entry(rctx);
 
 	return entry;