Messages in this thread | | | From | Bart Van Assche <> | Subject | [PATCH v2 00/24] locking/lockdep: Add support for dynamic keys | Date | Mon, 3 Dec 2018 16:28:09 -0800 |
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Hi Ingo and Peter,
A known shortcoming of the current lockdep implementation is that it requires lock keys to be allocated statically. This forces certain unrelated synchronization objects to share keys and this key sharing can cause false positive deadlock reports. This patch series adds support for dynamic keys in the lockdep code and eliminates a class of false positive reports from the workqueue implementation.
The changes compared to v1 are: - Addressed Peter's review comments: remove the list_head that I had added to struct lock_list again, replaced all_list_entries and free_list_entries by two bitmaps, use call_rcu() to free lockdep objects, add a BUILD_BUG_ON() that compares the size of struct lock_class_key and raw_spin_lock_t. - Addressed the "unknown symbol" errors reported by the build bot by adding a few #ifdef / #endif directives. Addressed the 32-bit warnings by using %d instead of %ld for array indices and by casting the array indices to unsigned int. - Removed several WARN_ON_ONCE(!class->hash_entry.pprev) statements since these duplicate the code in check_data_structures(). - Left out the patch that causes lockdep to complain if no name has been assigned to a lock object. That patch namely causes the build bot to complain about certain lock objects but I have not yet had the time to figure out the identity of these lock objects.
Bart.
Bart Van Assche (24): lockdep tests: Display compiler warning and error messages lockdep tests: Fix shellcheck warnings lockdep tests: Improve testing accuracy lockdep tests: Run lockdep tests a second time under Valgrind liblockdep: Rename "trywlock" into "trywrlock" liblockdep: Add dummy print_irqtrace_events() implementation lockdep tests: Test the lockdep_reset_lock() implementation locking/lockdep: Declare local symbols static locking/lockdep: Inline __lockdep_init_map() locking/lockdep: Introduce lock_class_cache_is_registered() locking/lockdep: Remove a superfluous INIT_LIST_HEAD() statement locking/lockdep: Make concurrent lockdep_reset_lock() calls safe locking/lockdep: Stop using RCU primitives to access all_lock_classes locking/lockdep: Make zap_class() remove all matching lock order entries locking/lockdep: Reorder struct lock_class members locking/lockdep: Retain the class key and name while freeing a lock class locking/lockdep: Free lock classes that are no longer in use locking/lockdep: Reuse list entries that are no longer in use locking/lockdep: Check data structure consistency locking/lockdep: Introduce __lockdep_free_key_range() locking/lockdep: Verify whether lock objects are small enough to be used as class keys locking/lockdep: Add support for dynamic keys kernel/workqueue: Use dynamic lockdep keys for workqueues lockdep tests: Test dynamic key registration
include/linux/lockdep.h | 37 +- include/linux/workqueue.h | 28 +- kernel/locking/lockdep.c | 660 +++++++++++++++--- kernel/workqueue.c | 60 +- tools/lib/lockdep/include/liblockdep/common.h | 3 + tools/lib/lockdep/include/liblockdep/mutex.h | 12 +- tools/lib/lockdep/include/liblockdep/rwlock.h | 6 +- tools/lib/lockdep/lockdep.c | 5 + tools/lib/lockdep/run_tests.sh | 39 +- tools/lib/lockdep/tests/AA.sh | 2 + tools/lib/lockdep/tests/ABA.sh | 2 + tools/lib/lockdep/tests/ABBA.c | 12 + tools/lib/lockdep/tests/ABBA.sh | 2 + tools/lib/lockdep/tests/ABBA_2threads.sh | 2 + tools/lib/lockdep/tests/ABBCCA.c | 4 + tools/lib/lockdep/tests/ABBCCA.sh | 2 + tools/lib/lockdep/tests/ABBCCDDA.c | 5 + tools/lib/lockdep/tests/ABBCCDDA.sh | 2 + tools/lib/lockdep/tests/ABCABC.c | 4 + tools/lib/lockdep/tests/ABCABC.sh | 2 + tools/lib/lockdep/tests/ABCDBCDA.c | 5 + tools/lib/lockdep/tests/ABCDBCDA.sh | 2 + tools/lib/lockdep/tests/ABCDBDDA.c | 5 + tools/lib/lockdep/tests/ABCDBDDA.sh | 2 + tools/lib/lockdep/tests/WW.sh | 2 + tools/lib/lockdep/tests/unlock_balance.c | 2 + tools/lib/lockdep/tests/unlock_balance.sh | 2 + 27 files changed, 744 insertions(+), 165 deletions(-) create mode 100755 tools/lib/lockdep/tests/AA.sh create mode 100755 tools/lib/lockdep/tests/ABA.sh create mode 100755 tools/lib/lockdep/tests/ABBA.sh create mode 100755 tools/lib/lockdep/tests/ABBA_2threads.sh create mode 100755 tools/lib/lockdep/tests/ABBCCA.sh create mode 100755 tools/lib/lockdep/tests/ABBCCDDA.sh create mode 100755 tools/lib/lockdep/tests/ABCABC.sh create mode 100755 tools/lib/lockdep/tests/ABCDBCDA.sh create mode 100755 tools/lib/lockdep/tests/ABCDBDDA.sh create mode 100755 tools/lib/lockdep/tests/WW.sh create mode 100755 tools/lib/lockdep/tests/unlock_balance.sh
-- 2.20.0.rc1.387.gf8505762e3-goog
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