[kvm-unit-tests PATCH 5/8] x86: replace per-AP bringup prints with a single summary line

[Giacomo Mazzola <gmazz@amazon.de>]

Remove the per-AP "CPU %d online" printf from ap_online() and the
per-CPU "enabling apic" printf from enable_apic().  Replace them
with a single "smp: %d CPUs online" message printed once after all
APs have come up.

On systems with many CPUs, the serial lock contention from per-AP
prints delays bringup long enough to trigger platform watchdogs.
A single summary line provides the same information without O(ncpus)
serial transactions during bringup.

Signed-off-by: Giacomo Mazzola <gmazz@amazon.de>
---
 lib/x86/apic.c | 1 -
 lib/x86/smp.c  | 4 ++--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/x86/apic.c b/lib/x86/apic.c
index c538fb5f..483b26d3 100644
--- a/lib/x86/apic.c
+++ b/lib/x86/apic.c
@@ -237,7 +237,6 @@ void set_irq_line(unsigned line, int val)
 
 void enable_apic(void)
 {
-	printf("enabling apic\n");
 	xapic_write(APIC_SPIV, 0x1ff);
 }
 
diff --git a/lib/x86/smp.c b/lib/x86/smp.c
index 0cd44cdc..706f071a 100644
--- a/lib/x86/smp.c
+++ b/lib/x86/smp.c
@@ -97,7 +97,6 @@ void ap_online(void)
 {
 	sti();
 
-	printf("setup: CPU %" PRId32 " online\n", apic_id());
 	atomic_inc(&cpu_online_count);
 
 	/* Only the BSP runs the test's main(), APs are given work via IPIs. */
@@ -294,7 +293,8 @@ void bringup_aps(void)
 
 	_cpu_count = fwcfg_get_nb_cpus();
 
-	printf("smp: waiting for %d APs\n", _cpu_count - 1);
 	while (_cpu_count != atomic_read(&cpu_online_count))
 		cpu_relax();
+
+	printf("smp: %d CPUs online\n", _cpu_count);
 }
-- 
2.47.3




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