On 2025-02-10 08:57, Gabriele Monaco wrote:
A task in the kernel (task_mm_cid_work) runs somewhat periodically to
compact the mm_cid for each process. Add a test to validate that it runs
correctly and timely.
The test spawns 1 thread pinned to each CPU, then each thread, including
the main one, runs in short bursts for some time. During this period, the
mm_cids should be spanning all numbers between 0 and nproc.
At the end of this phase, a thread with high enough mm_cid (>= nproc/2)
is selected to be the new leader, all other threads terminate.
After some time, the only running thread should see 0 as mm_cid, if that
doesn't happen, the compaction mechanism didn't work and the test fails.
The test never fails if only 1 core is available, in which case, we
cannot test anything as the only available mm_cid is 0.
To: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
tiny nit below:
+ usleep(RUNNER_PERIOD);
+ curr_mm_cid = rseq_current_mm_cid();
+ /*
+ * We select one thread with high enough mm_cid to be the new leader
Missing punctuation here (...new leader. All other...)
+ * all other threads (including the main thread) will terminate.
+ * After some time, the mm_cid of the only remaining thread should
+ * converge to 0, if not, the test fails.
+ */
Thanks,
Mathieu
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
