From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Byungchul Park To: peterz@infradead.org, mingo@kernel.org, axboe@kernel.dk Cc: johan@kernel.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, tj@kernel.org, johannes.berg@intel.com, oleg@redhat.com, amir73il@gmail.com, david@fromorbit.com, darrick.wong@oracle.com, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, hch@infradead.org, idryomov@gmail.com, kernel-team@lge.com Subject: [PATCH v4 4/7] locking/lockdep: Introduce CONFIG_BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK Date: Wed, 25 Oct 2017 14:11:09 +0900 Message-Id: <1508908272-15757-5-git-send-email-byungchul.park@lge.com> In-Reply-To: <1508908272-15757-1-git-send-email-byungchul.park@lge.com> References: <1508908272-15757-1-git-send-email-byungchul.park@lge.com> Sender: owner-linux-mm@kvack.org List-ID: The boot parameter, crossrelease_fullstack, was introduced to control whether to enable unwind in cross-release or not. Add a Kconfig doing the same thing. Suggested-by: Ingo Molnar Signed-off-by: Byungchul Park --- kernel/locking/lockdep.c | 4 ++++ lib/Kconfig.debug | 15 +++++++++++++++ 2 files changed, 19 insertions(+) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 160b5d6..db933d0 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -76,7 +76,11 @@ #define lock_stat 0 #endif +#ifdef CONFIG_BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK +static int crossrelease_fullstack = 1; +#else static int crossrelease_fullstack; +#endif static int __init allow_crossrelease_fullstack(char *str) { crossrelease_fullstack = 1; diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 4bef610..e4b54a5 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1225,6 +1225,21 @@ config LOCKDEP_COMPLETIONS A deadlock caused by wait_for_completion() and complete() can be detected by lockdep using crossrelease feature. +config BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK + bool "Enable the boot parameter, crossrelease_fullstack" + depends on LOCKDEP_CROSSRELEASE + default n + help + The lockdep "cross-release" feature needs to record stack traces + (of calling functions) for all acquisitions, for eventual later + use during analysis. By default only a single caller is recorded, + because the unwind operation can be very expensive with deeper + stack chains. + + However a boot parameter, crossrelease_fullstack, was + introduced since sometimes deeper traces are required for full + analysis. This option turns on the boot parameter. + config DEBUG_LOCKDEP bool "Lock dependency engine debugging" depends on DEBUG_KERNEL && LOCKDEP -- 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