+cc
linux-mm@kvack.org akpm@linux-foundation.org mhocko@kernel.org minchan@kernel.org hannes@cmpxchg.org vdavydov.dev@gmail.com sj@kernel.org jglisse@redhat.com dennis@kernel.org cl@linux.com penberg@kernel.org rientjes@google.com vbabka@suse.cz ngupta@vflare.org linux-block@vger.kernel.org axboe@kernel.dk paolo.valente@linaro.org josef@toxicpanda.com linux-fsdevel@vger.kernel.org viro@zeniv.linux.org.uk jack@suse.cz jlayton@kernel.org dan.j.williams@intel.com hch@infradead.org djwong@kernel.org dri-devel@lists.freedesktop.org airlied@linux.ie rodrigosiqueiramelo@gmail.com melissa.srw@gmail.com hamohammed.sa@gmail.com
--->8---
From 68ee7ab996fc7d67b6b506f48da106493ca2546a Mon Sep 17 00:00:00 2001
From: Byungchul Park byungchul.park@lge.com Date: Tue, 25 Jan 2022 10:12:54 +0900 Subject: [RFC 00/14] DEPT(DEPendency Tracker)
Hi forks,
I've been developing a tool for detecting deadlock possibilities by tracking wait/event rather than lock(?) acquisition order to try to cover all synchonization machanisms. It's done on v5.10 tag. I bet it would work great! Try it and see what's gonna happen.
Now that there's a porting issue, I made Dept rely on Lockdep. But it should be separated from Lockdep once it's considered worth having.
Benifit:
0. Works with all lock primitives. 1. Works with wait_for_completion()/complete(). 2. Works with 'wait' on PG_locked. 3. Works with 'wait' on PG_writeback. 4. Works with swait/wakeup. 5. Multiple reports are allowed. 6. Deduplication control on multiple reports. 7. Withstand false positives thanks to 5. 8. Easy to tag any wait/event.
Future work:
0. To make it more stable. 1. To separates Dept from Lockdep. 2. To improves performance in terms of time and space. 3. To use Dept as a dependency engine for Lockdep. 4. To add any missing tags of wait/event in the kernel. 5. To deduplicate stack trace.
I hope you guys are gonna be satisfied with Dept. Don't hesitate to give any feedback. I will adopt any feedbacks if reasonable.
Thanks, Byungchul
Byungchul Park (14): llist: Move llist_{head,node} definition to types.h dept: Implement Dept(Dependency Tracker) dept: Embed Dept data in Lockdep dept: Apply Dept to spinlock dept: Apply Dept to mutex families dept: Apply Dept to rwlock dept: Apply Dept to wait_for_completion()/complete() dept: Apply Dept to seqlock dept: Apply Dept to rwsem dept: Add proc knobs to show stats and dependency graph dept: Introduce split map concept and new APIs for them dept: Apply Dept to wait/event of PG_{locked,writeback} dept: Separate out SDT(Single-event Dependency Tracker) header dept: Apply SDT to swait
include/linux/completion.h | 48 +- include/linux/dept.h | 541 ++++++++ include/linux/dept_page.h | 71 + include/linux/dept_sdt.h | 53 + include/linux/hardirq.h | 3 + include/linux/irqflags.h | 33 +- include/linux/llist.h | 9 +- include/linux/lockdep.h | 156 ++- include/linux/lockdep_types.h | 3 + include/linux/mutex.h | 31 + include/linux/page-flags.h | 26 +- include/linux/pagemap.h | 7 +- include/linux/percpu-rwsem.h | 10 +- include/linux/rtmutex.h | 11 +- include/linux/rwlock.h | 48 + include/linux/rwlock_api_smp.h | 8 +- include/linux/rwlock_types.h | 7 + include/linux/rwsem.h | 31 + include/linux/sched.h | 3 + include/linux/seqlock.h | 19 +- include/linux/spinlock.h | 24 + include/linux/spinlock_types.h | 10 + include/linux/swait.h | 4 + include/linux/types.h | 8 + init/init_task.c | 2 + init/main.c | 4 + kernel/Makefile | 1 + kernel/dependency/Makefile | 5 + kernel/dependency/dept.c | 2593 +++++++++++++++++++++++++++++++++++++ kernel/dependency/dept_hash.h | 11 + kernel/dependency/dept_internal.h | 26 + kernel/dependency/dept_object.h | 14 + kernel/dependency/dept_proc.c | 97 ++ kernel/exit.c | 1 + kernel/fork.c | 2 + kernel/locking/lockdep.c | 12 +- kernel/module.c | 2 + kernel/sched/completion.c | 12 +- kernel/sched/swait.c | 8 + kernel/softirq.c | 6 +- kernel/trace/trace_preemptirq.c | 19 +- lib/Kconfig.debug | 21 + mm/filemap.c | 62 + mm/page_ext.c | 5 + 44 files changed, 4009 insertions(+), 58 deletions(-) create mode 100644 include/linux/dept.h create mode 100644 include/linux/dept_page.h create mode 100644 include/linux/dept_sdt.h create mode 100644 kernel/dependency/Makefile create mode 100644 kernel/dependency/dept.c create mode 100644 kernel/dependency/dept_hash.h create mode 100644 kernel/dependency/dept_internal.h create mode 100644 kernel/dependency/dept_object.h create mode 100644 kernel/dependency/dept_proc.c