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Signed-off-by: Isaev, Ilya <[email protected]>

src/tbb/tcm_adaptor.cpp

@@ -137,6 +137,8 @@ class tcm_client : public pm_client {
             // The permit has changed during the reading, so the callback will be invoked soon one more time and
             // we can just skip this renegotiation iteration.
             if (!new_permit.flags.stale) {
+                // If no other demand, the permit may still have granted concurrency but deactivated state and
+                // thus we need to enforce 0 allotment for arena so threads won't be trapped in it.
                 delta = update_concurrency(new_permit.state != TCM_PERMIT_STATE_INACTIVE ? new_concurrency : 0);
             }
         }