Merge tag 'bitmap-6.0-rc2' of https://github.com/norov/linux

Pull bitmap updates from Yury Norov:
 "cpumask: UP optimisation fixes follow-up

  As an older version of the UP optimisation fixes was merged, not all
  review feedback has been implemented.

  This implements the feedback received on the merged version [1], and
  the respin [2], for changes related to <linux/cpumask.h> and
  lib/cpumask.c"

Link: https://lore.kernel.org/lkml/[email protected]/ [1]
Link: https://lore.kernel.org/lkml/[email protected]/ [2]

It spent for more than a week with no issues.

* tag 'bitmap-6.0-rc2' of https://github.com/norov/linux:
  lib/cpumask: drop always-true preprocessor guard
  lib/cpumask: add inline cpumask_next_wrap() for UP
  cpumask: align signatures of UP implementations

Author: torvalds

include/linux/cpumask.h

@@ -202,12 +202,13 @@ static inline unsigned int cpumask_local_spread(unsigned int i, int node)
 	return 0;
 }
 
-static inline int cpumask_any_and_distribute(const struct cpumask *src1p,
-					     const struct cpumask *src2p) {
+static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
+						      const struct cpumask *src2p)
+{
 	return cpumask_first_and(src1p, src2p);
 }
 
-static inline int cpumask_any_distribute(const struct cpumask *srcp)
+static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp)
 {
 	return cpumask_first(srcp);
 }
@@ -261,7 +262,26 @@ unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
 		(cpu) = cpumask_next_zero((cpu), (mask)),	\
 		(cpu) < nr_cpu_ids;)
 
+#if NR_CPUS == 1
+static inline
+unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
+{
+	cpumask_check(start);
+	if (n != -1)
+		cpumask_check(n);
+
+	/*
+	 * Return the first available CPU when wrapping, or when starting before cpu0,
+	 * since there is only one valid option.
+	 */
+	if (wrap && n >= 0)
+		return nr_cpumask_bits;
+
+	return cpumask_first(mask);
+}
+#else
 unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
+#endif
 
 /**
  * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location

lib/Makefile

@@ -34,9 +34,10 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
 	 is_single_threaded.o plist.o decompress.o kobject_uevent.o \
 	 earlycpio.o seq_buf.o siphash.o dec_and_lock.o \
 	 nmi_backtrace.o win_minmax.o memcat_p.o \
-	 buildid.o cpumask.o
+	 buildid.o
 
 lib-$(CONFIG_PRINTK) += dump_stack.o
+lib-$(CONFIG_SMP) += cpumask.o
 
 lib-y	+= kobject.o klist.o
 obj-y	+= lockref.o

lib/cpumask.c

@@ -109,7 +109,6 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask)
 }
 #endif
 
-#if NR_CPUS > 1
 /**
  * cpumask_local_spread - select the i'th cpu with local numa cpu's first
  * @i: index number
@@ -197,4 +196,3 @@ unsigned int cpumask_any_distribute(const struct cpumask *srcp)
 	return next;
 }
 EXPORT_SYMBOL(cpumask_any_distribute);
-#endif /* NR_CPUS */