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Diffstat (limited to 'kernel/smpboot.c')
-rw-r--r--kernel/smpboot.c15
1 files changed, 8 insertions, 7 deletions
diff --git a/kernel/smpboot.c b/kernel/smpboot.c
index b9f54544e749..2c7396da470c 100644
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -433,7 +433,7 @@ bool cpu_wait_death(unsigned int cpu, int seconds)
/* The outgoing CPU will normally get done quite quickly. */
if (atomic_read(&per_cpu(cpu_hotplug_state, cpu)) == CPU_DEAD)
- goto update_state;
+ goto update_state_early;
udelay(5);
/* But if the outgoing CPU dawdles, wait increasingly long times. */
@@ -444,16 +444,17 @@ bool cpu_wait_death(unsigned int cpu, int seconds)
break;
sleep_jf = DIV_ROUND_UP(sleep_jf * 11, 10);
}
-update_state:
+update_state_early:
oldstate = atomic_read(&per_cpu(cpu_hotplug_state, cpu));
+update_state:
if (oldstate == CPU_DEAD) {
/* Outgoing CPU died normally, update state. */
smp_mb(); /* atomic_read() before update. */
atomic_set(&per_cpu(cpu_hotplug_state, cpu), CPU_POST_DEAD);
} else {
/* Outgoing CPU still hasn't died, set state accordingly. */
- if (atomic_cmpxchg(&per_cpu(cpu_hotplug_state, cpu),
- oldstate, CPU_BROKEN) != oldstate)
+ if (!atomic_try_cmpxchg(&per_cpu(cpu_hotplug_state, cpu),
+ &oldstate, CPU_BROKEN))
goto update_state;
ret = false;
}
@@ -475,14 +476,14 @@ bool cpu_report_death(void)
int newstate;
int cpu = smp_processor_id();
+ oldstate = atomic_read(&per_cpu(cpu_hotplug_state, cpu));
do {
- oldstate = atomic_read(&per_cpu(cpu_hotplug_state, cpu));
if (oldstate != CPU_BROKEN)
newstate = CPU_DEAD;
else
newstate = CPU_DEAD_FROZEN;
- } while (atomic_cmpxchg(&per_cpu(cpu_hotplug_state, cpu),
- oldstate, newstate) != oldstate);
+ } while (!atomic_try_cmpxchg(&per_cpu(cpu_hotplug_state, cpu),
+ &oldstate, newstate));
return newstate == CPU_DEAD;
}