From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id E79936B02B4 for ; Mon, 7 Aug 2017 03:14:13 -0400 (EDT) Received: by mail-pf0-f200.google.com with SMTP id r187so86592804pfr.8 for ; Mon, 07 Aug 2017 00:14:13 -0700 (PDT) Received: from lgeamrelo12.lge.com (LGEAMRELO12.lge.com. [156.147.23.52]) by mx.google.com with ESMTP id h90si4877450plb.303.2017.08.07.00.14.12 for ; Mon, 07 Aug 2017 00:14:12 -0700 (PDT) From: Byungchul Park Subject: [PATCH v8 03/14] lockdep: Change the meaning of check_prev_add()'s return value Date: Mon, 7 Aug 2017 16:12:50 +0900 Message-Id: <1502089981-21272-4-git-send-email-byungchul.park@lge.com> In-Reply-To: <1502089981-21272-1-git-send-email-byungchul.park@lge.com> References: <1502089981-21272-1-git-send-email-byungchul.park@lge.com> Sender: owner-linux-mm@kvack.org List-ID: To: peterz@infradead.org, mingo@kernel.org Cc: tglx@linutronix.de, walken@google.com, boqun.feng@gmail.com, kirill@shutemov.name, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, willy@infradead.org, npiggin@gmail.com, kernel-team@lge.com Firstly, return 1 instead of 2 when 'prev -> next' dependency already exists. Since the value 2 is not referenced anywhere, just return 1 indicating success in this case. Secondly, return 2 instead of 1 when successfully added a lock_list entry with saving stack_trace. With that, a caller can decide whether to avoid redundant save_trace() on the caller site. Signed-off-by: Byungchul Park --- kernel/locking/lockdep.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 9d16723..b23e930 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1870,7 +1870,7 @@ static inline void inc_chains(void) if (entry->class == hlock_class(next)) { if (distance == 1) entry->distance = 1; - return 2; + return 1; } } @@ -1910,9 +1910,10 @@ static inline void inc_chains(void) print_lock_name(hlock_class(next)); printk(KERN_CONT "\n"); dump_stack(); - return graph_lock(); + if (!graph_lock()) + return 0; } - return 1; + return 2; } /* -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org