As I know, there was no mobilization, nor public alarm in the USSR. Also Sino-Soviet friendship treaty continued to function as well as all trade agreements throughout the whole period of clashes.
How this was possible? Did Chinese government made it clear that the conflict will not escalate and all the treaties remain in force? What was the official version of the clashes?
I suspect two variants
Chinese claimed that they were attacked themselves by the USSR but really wanted peace
Chinese claimed that the attacks on Russian territory were by uncontrolled units or groups.
Maybe there could be other explanation. Who knows what was the official Chinese position in reality?