[linux-next:master 9885/10451] kernel/rcu/tree_stall.h:797:undefined reference to `csd_lock_is_stuck'

[linux-next:master 9885/10451] kernel/rcu/tree_stall.h:797:undefined reference to `csd_lock_is_stuck'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   0b58e108042b0ed28a71cd7edf5175999955b233
commit: 3be88389f46263f166973e80e528dcc9268e24cb [9885/10451] rcu: Summarize RCU CPU stall warnings during CSD-lock stalls
config: x86_64-randconfig-a014-20211016 (https://download.01.org/0day-ci/archive/20240703/202407031722.nBIh2u7x-lkp@intel.com/config)
compiler: gcc-13 (Ubuntu 13.2.0-4ubuntu3) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240703/202407031722.nBIh2u7x-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407031722.nBIh2u7x-lkp@intel.com/

All errors (new ones prefixed by >>):

   ld: vmlinux.o: in function `check_cpu_stall':
>> kernel/rcu/tree_stall.h:797:(.text+0x273b89): undefined reference to `csd_lock_is_stuck'


vim +797 kernel/rcu/tree_stall.h

   724	
   725	static void check_cpu_stall(struct rcu_data *rdp)
   726	{
   727		bool self_detected;
   728		unsigned long gs1;
   729		unsigned long gs2;
   730		unsigned long gps;
   731		unsigned long j;
   732		unsigned long jn;
   733		unsigned long js;
   734		struct rcu_node *rnp;
   735	
   736		lockdep_assert_irqs_disabled();
   737		if ((rcu_stall_is_suppressed() && !READ_ONCE(rcu_kick_kthreads)) ||
   738		    !rcu_gp_in_progress())
   739			return;
   740		rcu_stall_kick_kthreads();
   741	
   742		/*
   743		 * Check if it was requested (via rcu_cpu_stall_reset()) that the FQS
   744		 * loop has to set jiffies to ensure a non-stale jiffies value. This
   745		 * is required to have good jiffies value after coming out of long
   746		 * breaks of jiffies updates. Not doing so can cause false positives.
   747		 */
   748		if (READ_ONCE(rcu_state.nr_fqs_jiffies_stall) > 0)
   749			return;
   750	
   751		j = jiffies;
   752	
   753		/*
   754		 * Lots of memory barriers to reject false positives.
   755		 *
   756		 * The idea is to pick up rcu_state.gp_seq, then
   757		 * rcu_state.jiffies_stall, then rcu_state.gp_start, and finally
   758		 * another copy of rcu_state.gp_seq.  These values are updated in
   759		 * the opposite order with memory barriers (or equivalent) during
   760		 * grace-period initialization and cleanup.  Now, a false positive
   761		 * can occur if we get an new value of rcu_state.gp_start and a old
   762		 * value of rcu_state.jiffies_stall.  But given the memory barriers,
   763		 * the only way that this can happen is if one grace period ends
   764		 * and another starts between these two fetches.  This is detected
   765		 * by comparing the second fetch of rcu_state.gp_seq with the
   766		 * previous fetch from rcu_state.gp_seq.
   767		 *
   768		 * Given this check, comparisons of jiffies, rcu_state.jiffies_stall,
   769		 * and rcu_state.gp_start suffice to forestall false positives.
   770		 */
   771		gs1 = READ_ONCE(rcu_state.gp_seq);
   772		smp_rmb(); /* Pick up ->gp_seq first... */
   773		js = READ_ONCE(rcu_state.jiffies_stall);
   774		smp_rmb(); /* ...then ->jiffies_stall before the rest... */
   775		gps = READ_ONCE(rcu_state.gp_start);
   776		smp_rmb(); /* ...and finally ->gp_start before ->gp_seq again. */
   777		gs2 = READ_ONCE(rcu_state.gp_seq);
   778		if (gs1 != gs2 ||
   779		    ULONG_CMP_LT(j, js) ||
   780		    ULONG_CMP_GE(gps, js))
   781			return; /* No stall or GP completed since entering function. */
   782		rnp = rdp->mynode;
   783		jn = jiffies + ULONG_MAX / 2;
   784		self_detected = READ_ONCE(rnp->qsmask) & rdp->grpmask;
   785		if (rcu_gp_in_progress() &&
   786		    (self_detected || ULONG_CMP_GE(j, js + RCU_STALL_RAT_DELAY)) &&
   787		    cmpxchg(&rcu_state.jiffies_stall, js, jn) == js) {
   788			/*
   789			 * If a virtual machine is stopped by the host it can look to
   790			 * the watchdog like an RCU stall. Check to see if the host
   791			 * stopped the vm.
   792			 */
   793			if (kvm_check_and_clear_guest_paused())
   794				return;
   795	
   796			rcu_stall_notifier_call_chain(RCU_STALL_NOTIFY_NORM, (void *)j - gps);
 > 797			if (READ_ONCE(csd_lock_suppress_rcu_stall) && csd_lock_is_stuck()) {
   798				pr_err("INFO: %s detected stall, but suppressed full report due to a stuck CSD-lock.\n", rcu_state.name);
   799			} else if (self_detected) {
   800				/* We haven't checked in, so go dump stack. */
   801				print_cpu_stall(gps);
   802			} else {
   803				/* They had a few time units to dump stack, so complain. */
   804				print_other_cpu_stall(gs2, gps);
   805			}
   806	
   807			if (READ_ONCE(rcu_cpu_stall_ftrace_dump))
   808				rcu_ftrace_dump(DUMP_ALL);
   809	
   810			if (READ_ONCE(rcu_state.jiffies_stall) == jn) {
   811				jn = jiffies + 3 * rcu_jiffies_till_stall_check() + 3;
   812				WRITE_ONCE(rcu_state.jiffies_stall, jn);
   813			}
   814		}
   815	}
   816	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki