[PATCH -v1.4] x86, boot: Further compress CPUs bootup message

From: Borislav Petkov
Date: Sun Sep 29 2013 - 11:17:58 EST


From: Borislav Petkov <bp@xxxxxxx>

Turn it into (for example):

[ 0.073380] x86: Booting SMP configuration:
[ 0.074005] .... node #0, CPUs: #1 #2 #3 #4 #5 #6 #7
[ 0.603005] .... node #1, CPUs: #8 #9 #10 #11 #12 #13 #14 #15
[ 1.200005] .... node #2, CPUs: #16 #17 #18 #19 #20 #21 #22 #23
[ 1.796005] .... node #3, CPUs: #24 #25 #26 #27 #28 #29 #30 #31
[ 2.393005] .... node #4, CPUs: #32 #33 #34 #35 #36 #37 #38 #39
[ 2.996005] .... node #5, CPUs: #40 #41 #42 #43 #44 #45 #46 #47
[ 3.600005] .... node #6, CPUs: #48 #49 #50 #51 #52 #53 #54 #55
[ 4.202005] .... node #7, CPUs: #56 #57 #58 #59 #60 #61 #62 #63
[ 4.811005] .... node #8, CPUs: #64 #65 #66 #67 #68 #69 #70 #71
[ 5.421006] .... node #9, CPUs: #72 #73 #74 #75 #76 #77 #78 #79
[ 6.032005] .... node #10, CPUs: #80 #81 #82 #83 #84 #85 #86 #87
[ 6.648006] .... node #11, CPUs: #88 #89 #90 #91 #92 #93 #94 #95
[ 7.262005] .... node #12, CPUs: #96 #97 #98 #99 #100 #101 #102 #103
[ 7.865005] .... node #13, CPUs: #104 #105 #106 #107 #108 #109 #110 #111
[ 8.466005] .... node #14, CPUs: #112 #113 #114 #115 #116 #117 #118 #119
[ 9.073006] .... node #15, CPUs: #120 #121 #122 #123 #124 #125 #126 #127
[ 9.679901] x86: Booted up 16 nodes, 128 CPUs

and drop useless elements.

Change num_digits() to hpa's division-avoiding, cell-phone-typed version
which he went at great lengths and pains to submit on a Saturday
evening.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/kernel/smpboot.c | 24 +++++++++++++++++++-----
arch/x86/lib/misc.c | 18 ++++++++++++------
kernel/smp.c | 7 ++++++-
3 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index d41f3ba26ced..2a165580fa16 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -647,22 +647,38 @@ 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)
{
static int current_node = -1;
int node = early_cpu_to_node(cpu);
- static int width;
+ static int width, node_width;

if (!width)
width = num_digits(num_possible_cpus()) + 1; /* + '#' sign */

+ if (!node_width)
+ node_width = num_digits(num_possible_nodes()) + 1; /* + '#' */
+
+ if (cpu == 1)
+ printk(KERN_INFO "x86: Booting SMP configuration:\n");
+
if (system_state == SYSTEM_BOOTING) {
if (node != current_node) {
if (current_node > (-1))
- pr_cont(" OK\n");
+ pr_cont("\n");
current_node = node;
- pr_info("Booting Node %3d, Processors:", node);
+
+ printk(KERN_INFO ".... node %*s#%d, CPUs: ",
+ node_width - num_digits(node), " ", node);
}

/* Add padding for the BSP */
@@ -671,8 +687,6 @@ static void announce_cpu(int cpu, int apicid)

pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu);

- if (cpu == num_present_cpus() - 1)
- pr_cont(" OK\n");
} else
pr_info("Booting Node %d Processor %d APIC 0x%x\n",
node, cpu, apicid);
diff --git a/arch/x86/lib/misc.c b/arch/x86/lib/misc.c
index bc35cde9769f..9acca74a0833 100644
--- a/arch/x86/lib/misc.c
+++ b/arch/x86/lib/misc.c
@@ -1,11 +1,17 @@
+/*
+ * Count only the digits in @val, without the sign
+ */
int num_digits(int val)
{
- int digits = 0;
+ int m = 10;
+ int d = 1;

- while (val) {
- val /= 10;
- digits++;
- }
+ if (val < 0)
+ val = -val;

- return digits;
+ while (val >= m) {
+ m *= 10;
+ d++;
+ }
+ return d;
}
diff --git a/kernel/smp.c b/kernel/smp.c
index 0564571dcdf7..f5768b0c816a 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -524,6 +524,11 @@ 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)
{
@@ -540,7 +545,7 @@ void __init smp_init(void)
}

/* Any cleanup work */
- printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
+ smp_announce();
smp_cpus_done(setup_max_cpus);
}

--
1.8.4

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