summaryrefslogtreecommitdiff
path: root/kernel/kcsan/atomic.h
AgeCommit message (Collapse)Author
2020-06-29kcsan: Remove existing special atomic rulesMarco Elver
Remove existing special atomic rules from kcsan_is_atomic_special() because they are no longer needed. Since we rely on the compiler emitting instrumentation distinguishing volatile accesses, the rules have become redundant. Let's keep kcsan_is_atomic_special() around, so that we have an obvious place to add special rules should the need arise in future. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-03-25kcsan: Add current->state to implicitly atomic accessesMarco Elver
Add volatile current->state to list of implicitly atomic accesses. This is in preparation to eventually enable KCSAN on kernel/sched (which currently still has KCSAN_SANITIZE := n). Since accesses that match the special check in atomic.h are rare, it makes more sense to move this check to the slow-path, avoiding the additional compare in the fast-path. With the microbenchmark, a speedup of ~6% is measured. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-03-21kcsan: Prefer __always_inline for fast-pathMarco Elver
Prefer __always_inline for fast-path functions that are called outside of user_access_save, to avoid generating UACCESS warnings when optimizing for size (CC_OPTIMIZE_FOR_SIZE). It will also avoid future surprises with compiler versions that change the inlining heuristic even when optimizing for performance. Reported-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/58708908-84a0-0a81-a836-ad97e33dbb62@infradead.org
2019-11-20kcsan: Improve various small stylistic detailsIngo Molnar
Tidy up a few bits: - Fix typos and grammar, improve wording. - Remove spurious newlines that are col80 warning artifacts where the resulting line-break is worse than the disease it's curing. - Use core kernel coding style to improve readability and reduce spurious code pattern variations. - Use better vertical alignment for structure definitions and initialization sequences. - Misc other small details. No change in functionality intended. Cc: linux-kernel@vger.kernel.org Cc: Marco Elver <elver@google.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-16kcsan: Add Kernel Concurrency Sanitizer infrastructureMarco Elver
Kernel Concurrency Sanitizer (KCSAN) is a dynamic data-race detector for kernel space. KCSAN is a sampling watchpoint-based data-race detector. See the included Documentation/dev-tools/kcsan.rst for more details. This patch adds basic infrastructure, but does not yet enable KCSAN for any architecture. Signed-off-by: Marco Elver <elver@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>