Commit db7f47cf authored by Paul Menage's avatar Paul Menage Committed by Linus Torvalds
Browse files

cpusets: allow cpusets to be configured/built on non-SMP systems 



Allow cpusets to be configured/built on non-SMP systems

Currently it's impossible to build cpusets under UML on x86-64, since
cpusets depends on SMP and x86-64 UML doesn't support SMP.

There's code in cpusets that doesn't depend on SMP.  This patch surrounds
the minimum amount of cpusets code with #ifdef CONFIG_SMP in order to
allow cpusets to build/run on UP systems (for testing purposes under UML).

Reviewed-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: default avatarPaul Menage <menage@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a1bc5a4e

init/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -531,7 +531,7 @@ config CGROUP_DEVICE 


config CPUSETS

	bool "Cpuset support"

	depends on SMP && CGROUPS

	depends on CGROUPS

	help

	  This option will let you create and manage CPUSETs which

	  allow dynamically partitioning a system into sets of CPUs and

kernel/cpuset.c

+15 −0
Original line number Diff line number Diff line
@@ -517,6 +517,7 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial) 
	return 0;

}



#ifdef CONFIG_SMP

/*

 * Helper routine for generate_sched_domains().

 * Do cpusets a, b have overlapping cpus_allowed masks?
@@ -811,6 +812,18 @@ static void do_rebuild_sched_domains(struct work_struct *unused) 


	put_online_cpus();

}

#else /* !CONFIG_SMP */

static void do_rebuild_sched_domains(struct work_struct *unused)

{

}



static int generate_sched_domains(struct cpumask **domains,

			struct sched_domain_attr **attributes)

{

	*domains = NULL;

	return 1;

}

#endif /* CONFIG_SMP */



static DECLARE_WORK(rebuild_sched_domains_work, do_rebuild_sched_domains);
@@ -1164,8 +1177,10 @@ int current_cpuset_is_being_rebound(void) 


static int update_relax_domain_level(struct cpuset *cs, s64 val)

{

#ifdef CONFIG_SMP

	if (val < -1 || val >= SD_LV_MAX)

		return -EINVAL;

#endif



	if (val != cs->relax_domain_level) {

		cs->relax_domain_level = val;

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