[PATCH] PM / sleep: console flush during suspend if no_console_suspend enabled

From: Bibek Basu
Date: Mon Dec 21 2015 - 01:32:05 EST


On multicore CPUs, sometimes debug console logs are not flushed
if you have VT consoles also enabled. Reason being console_lock
is taken by secondary/nonboot cpus which are disabled as part
of suspend.This patch flushes the console before disabling
nonboot cpus

Signed-off-by: Bibek Basu <bbasu@xxxxxxxxxx>
---
kernel/power/suspend.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index f9fe133..42c5912 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -352,6 +352,16 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
goto Platform_wake;
}

+ /*
+ * Flush console buffer if console_suspend_enabled cleared.
+ * This will enable console flush if console_lock is taken
+ * by nonboot cpus which will soon be disabled below.
+ */
+ if (!console_suspend_enabled) {
+ console_lock();
+ console_unlock();
+ }
+
error = disable_nonboot_cpus();
if (error || suspend_test(TEST_CPUS))
goto Enable_cpus;
--
2.1.4

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