From 1846a7fa767fbf8cf42d71daf75d51e30e3c8327 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 13 May 2021 11:17:02 -0700 Subject: [PATCH] tools/memory-model: Make read_foo_diagnostic() more clearly diagnostic The current definition of read_foo_diagnostic() in the "Lock Protection With Lockless Diagnostic Access" section returns a value, which could be use for any purpose. This could mislead people into incorrectly using data_race() in cases where READ_ONCE() is required. This commit therefore makes read_foo_diagnostic() simply print the value read. Reported-by: Manfred Spraul Signed-off-by: Paul E. McKenney --- tools/memory-model/Documentation/access-marking.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/memory-model/Documentation/access-marking.txt b/tools/memory-model/Documentation/access-marking.txt index 1ab189f51f55..58bff2619876 100644 --- a/tools/memory-model/Documentation/access-marking.txt +++ b/tools/memory-model/Documentation/access-marking.txt @@ -259,9 +259,9 @@ diagnostic purposes. The code might look as follows: return ret; } - int read_foo_diagnostic(void) + void read_foo_diagnostic(void) { - return data_race(foo); + pr_info("Current value of foo: %d\n", data_race(foo)); } The reader-writer lock prevents the compiler from introducing concurrency