+ rcu-tree_plugin-dont-handle-the-case-of-all-cpu-range.patch added to -mm tree

+ rcu-tree_plugin-dont-handle-the-case-of-all-cpu-range.patch added to -mm tree

[akpm]

The patch titled
     Subject: rcu/tree_plugin: don't handle the case of 'all' CPU range
has been added to the -mm tree.  Its filename is
     rcu-tree_plugin-dont-handle-the-case-of-all-cpu-range.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/rcu-tree_plugin-dont-handle-the-case-of-all-cpu-range.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/rcu-tree_plugin-dont-handle-the-case-of-all-cpu-range.patch

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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next and is updated
there every 3-4 working days

------------------------------------------------------
From: Yury Norov <yury.norov@gmail.com>
Subject: rcu/tree_plugin: don't handle the case of 'all' CPU range

The 'all' semantics is now supported by the bitmap_parselist() so we can
drop supporting it as a special case in RCU code.  Since 'all' is properly
supported in core bitmap code, drop legacy comment in RCU for it.

This patch does not add any functional changes for existing users.

Link: https://lkml.kernel.org/r/20210421031326.72816-3-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/rcu/tree_plugin.h |    9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

--- a/kernel/rcu/tree_plugin.h~rcu-tree_plugin-dont-handle-the-case-of-all-cpu-range
+++ a/kernel/rcu/tree_plugin.h
@@ -1535,13 +1535,10 @@ static void rcu_cleanup_after_idle(void)
 static int __init rcu_nocb_setup(char *str)
 {
 	alloc_bootmem_cpumask_var(&rcu_nocb_mask);
-	if (!strcasecmp(str, "all"))		/* legacy: use "0-N" instead */
+	if (cpulist_parse(str, rcu_nocb_mask)) {
+		pr_warn("rcu_nocbs= bad CPU range, all CPUs set\n");
 		cpumask_setall(rcu_nocb_mask);
-	else
-		if (cpulist_parse(str, rcu_nocb_mask)) {
-			pr_warn("rcu_nocbs= bad CPU range, all CPUs set\n");
-			cpumask_setall(rcu_nocb_mask);
-		}
+	}
 	return 1;
 }
 __setup("rcu_nocbs=", rcu_nocb_setup);
_

Patches currently in -mm which might be from yury.norov@gmail.com are

bitmap_parse-support-all-semantics.patch
rcu-tree_plugin-dont-handle-the-case-of-all-cpu-range.patch