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| author | Thomas Gleixner <tglx@linutronix.de> | 2019-07-22 20:47:16 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2019-07-25 15:47:37 +0200 |
| commit | e797bda3fd29137f6c151dfa10ea6a61c17895ce (patch) | |
| tree | cb0bbe066270a64ff96721d63c4b2c5c31cd2591 /kernel/cpu.c | |
| parent | ad5e427e0f6b702e52c11d1f7b2b7be3bac7de82 (diff) | |
| download | lwn-e797bda3fd29137f6c151dfa10ea6a61c17895ce.tar.gz lwn-e797bda3fd29137f6c151dfa10ea6a61c17895ce.zip | |
smp/hotplug: Track booted once CPUs in a cpumask
The booted once information which is required to deal with the MCE
broadcast issue on X86 correctly is stored in the per cpu hotplug state,
which is perfectly fine for the intended purpose.
X86 needs that information for supporting NMI broadcasting via shortcuts,
but retrieving it from per cpu data is cumbersome.
Move it to a cpumask so the information can be checked against the
cpu_present_mask quickly.
No functional change intended.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105219.818822855@linutronix.de
Diffstat (limited to 'kernel/cpu.c')
| -rw-r--r-- | kernel/cpu.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index e84c0873559e..05778e32674a 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -62,7 +62,6 @@ struct cpuhp_cpu_state { bool rollback; bool single; bool bringup; - bool booted_once; struct hlist_node *node; struct hlist_node *last; enum cpuhp_state cb_state; @@ -76,6 +75,10 @@ static DEFINE_PER_CPU(struct cpuhp_cpu_state, cpuhp_state) = { .fail = CPUHP_INVALID, }; +#ifdef CONFIG_SMP +cpumask_t cpus_booted_once_mask; +#endif + #if defined(CONFIG_LOCKDEP) && defined(CONFIG_SMP) static struct lockdep_map cpuhp_state_up_map = STATIC_LOCKDEP_MAP_INIT("cpuhp_state-up", &cpuhp_state_up_map); @@ -433,7 +436,7 @@ static inline bool cpu_smt_allowed(unsigned int cpu) * CPU. Otherwise, a broadacasted MCE observing CR4.MCE=0b on any * core will shutdown the machine. */ - return !per_cpu(cpuhp_state, cpu).booted_once; + return !cpumask_test_cpu(cpu, &cpus_booted_once_mask); } #else static inline bool cpu_smt_allowed(unsigned int cpu) { return true; } @@ -1066,7 +1069,7 @@ void notify_cpu_starting(unsigned int cpu) int ret; rcu_cpu_starting(cpu); /* Enables RCU usage on this CPU. */ - st->booted_once = true; + cpumask_set_cpu(cpu, &cpus_booted_once_mask); while (st->state < target) { st->state++; ret = cpuhp_invoke_callback(cpu, st->state, true, NULL, NULL); @@ -2334,7 +2337,7 @@ void __init boot_cpu_init(void) void __init boot_cpu_hotplug_init(void) { #ifdef CONFIG_SMP - this_cpu_write(cpuhp_state.booted_once, true); + cpumask_set_cpu(smp_processor_id(), &cpus_booted_once_mask); #endif this_cpu_write(cpuhp_state.state, CPUHP_ONLINE); } |