rcu/nocb: Fix dump_tree hierarchy print always active (610dea36) · Commits · 戴 / test

Commit ("rcu/nocb: Print gp/cb kthread hierarchy if dump_tree") added print statements to rcu_organize_nocb_kthreads for debugging, but incorrectly guarded them, causing the function to always spew out its message. This patch fixes it by guarding both pr_alert statements with dump_tree, while also changing the second pr_alert to a pr_cont, to print the hierarchy in a single line (assuming that's how it was supposed to work). Fixes: ("rcu/nocb: Print gp/cb kthread hierarchy if dump_tree") Signed-off-by:

Stefan Reiter <stefan@pimaker.at> [ paulmck: Make single-nocbs-CPU GP kthreads look less erroneous. ] Signed-off-by:

Paul E. McKenney <paulmck@kernel.org>

kernel/rcu/tree_plugin.h

+17 −5

Original line number	Diff line number	Diff line
		@@ -2321,6 +2321,8 @@ static void __init rcu_organize_nocb_kthreads(void)
		{
		int cpu;
		bool firsttime = true;
		bool gotnocbs = false;
		bool gotnocbscbs = true;
		int ls = rcu_nocb_gp_stride;
		int nl = 0; /* Next GP kthread. */
		struct rcu_data *rdp;
		@@ -2343,21 +2345,31 @@ static void __init rcu_organize_nocb_kthreads(void)
		rdp = per_cpu_ptr(&rcu_data, cpu);
		if (rdp->cpu >= nl) {
		/* New GP kthread, set up for CBs & next GP. */
		gotnocbs = true;
		nl = DIV_ROUND_UP(rdp->cpu + 1, ls) * ls;
		rdp->nocb_gp_rdp = rdp;
		rdp_gp = rdp;
		if (!firsttime && dump_tree)
		pr_cont("\n");
		if (dump_tree) {
		if (!firsttime)
		pr_cont("%s\n", gotnocbscbs
		? "" : " (self only)");
		gotnocbscbs = false;
		firsttime = false;
		pr_alert("%s: No-CB GP kthread CPU %d:", __func__, cpu);
		pr_alert("%s: No-CB GP kthread CPU %d:",
		__func__, cpu);
		}
		} else {
		/* Another CB kthread, link to previous GP kthread. */
		gotnocbscbs = true;
		rdp->nocb_gp_rdp = rdp_gp;
		rdp_prev->nocb_next_cb_rdp = rdp;
		pr_alert(" %d", cpu);
		if (dump_tree)
		pr_cont(" %d", cpu);
		}
		rdp_prev = rdp;
		}
		if (gotnocbs && dump_tree)
		pr_cont("%s\n", gotnocbscbs ? "" : " (self only)");
		}

		/*

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