Commit 18c23558 authored Nov 22, 2022 by Mathieu Desnoyers Committed by Peter Zijlstra Dec 27, 2022

selftests/rseq: Implement rseq mm_cid field support

Add support for the mm_cid field (per-memory-map concurrency ID) of
struct rseq to rseq selftests.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221122203932.231377-11-mathieu.desnoyers@efficios.com

parent 72cb1d7f

tools/testing/selftests/rseq/rseq-abi.h

+9 −0

Original line number	Diff line number	Diff line
		@@ -155,6 +155,15 @@ struct rseq_abi {
		*/
		__u32 node_id;

		/*
		* Restartable sequences mm_cid field. Updated by the kernel. Read by
		* user-space with single-copy atomicity semantics. This field should
		* only be read by the thread which registered this data structure.
		* Aligned on 32-bit. Contains the current thread's concurrency ID
		* (allocated uniquely within a memory map).
		*/
		__u32 mm_cid;

		/*
		* Flexible array member at end of structure, after last feature field.
		*/

tools/testing/selftests/rseq/rseq.h

+10 −0

Original line number	Diff line number	Diff line
		@@ -191,6 +191,16 @@ static inline uint32_t rseq_current_node_id(void)
		return RSEQ_ACCESS_ONCE(rseq_get_abi()->node_id);
		}

		static inline bool rseq_mm_cid_available(void)
		{
		return (int) rseq_feature_size >= rseq_offsetofend(struct rseq_abi, mm_cid);
		}

		static inline uint32_t rseq_current_mm_cid(void)
		{
		return RSEQ_ACCESS_ONCE(rseq_get_abi()->mm_cid);
		}

		static inline void rseq_clear_rseq_cs(void)
		{
		RSEQ_WRITE_ONCE(rseq_get_abi()->rseq_cs.arch.ptr, 0);