Commit 92b23278 authored Oct 26, 2016 by Michael Ellerman Committed by Thomas Gleixner Oct 26, 2016

kernel/smp: Make the SMP boot message common on all arches



Currently after bringing up secondary CPUs all arches print "Brought up
%d CPUs". On x86 they also print the number of nodes that were brought
online.

It would be nice to also print the number of nodes on other arches.
Although we could override smp_announce() on the other ~10 NUMA aware
arches, it seems simpler to just always print the number of nodes. On
non-NUMA arches there is just always 1 node.

Having done that, smp_announce() is no longer weak, and seems small
enough to just pull directly into smp_init().

Also update the printing of "%d CPUs" to be smart when an SMP kernel is
booted on a single CPU system, or when only one CPU is available, eg:

   smp: Brought up 2 nodes, 1 CPU

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: akpm@osdl.org
Cc: jgross@suse.com
Cc: ak@linux.intel.com
Cc: tim.c.chen@linux.intel.com
Cc: len.brown@intel.com
Cc: peterz@infradead.org
Cc: richard@nod.at
Cc: jolsa@redhat.com
Cc: boris.ostrovsky@oracle.com
Cc: mgorman@techsingularity.net
Link: http://lkml.kernel.org/r/1477460275-8266-2-git-send-email-mpe@ellerman.id.au


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

parent ca7dfdbb

arch/x86/kernel/smpboot.c

+0 −8

Original line number	Diff line number	Diff line
		@@ -821,14 +821,6 @@ wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
		return (send_status \| accept_status);
		}

		void smp_announce(void)
		{
		int num_nodes = num_online_nodes();

		printk(KERN_INFO "x86: Booted up %d node%s, %d CPUs\n",
		num_nodes, (num_nodes > 1 ? "s" : ""), num_online_cpus());
		}

		/* reduce the number of lines printed when booting a large cpu count system */
		static void announce_cpu(int cpu, int apicid)
		{

kernel/smp.c

+7 −6

Original line number	Diff line number	Diff line
		@@ -546,14 +546,10 @@ void __init setup_nr_cpu_ids(void)
		nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
		}

		void __weak smp_announce(void)
		{
		printk(KERN_INFO "Brought up %d CPUs\n", num_online_cpus());
		}

		/* Called by boot processor to activate the rest. */
		void __init smp_init(void)
		{
		int num_nodes, num_cpus;
		unsigned int cpu;

		idle_threads_init();
		@@ -567,8 +563,13 @@ void __init smp_init(void)
		cpu_up(cpu);
		}

		num_nodes = num_online_nodes();
		num_cpus = num_online_cpus();
		pr_info("Brought up %d node%s, %d CPU%s\n",
		num_nodes, (num_nodes > 1 ? "s" : ""),
		num_cpus, (num_cpus > 1 ? "s" : ""));

		/* Any cleanup work */
		smp_announce();
		smp_cpus_done(setup_max_cpus);
		}

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