diff options
| -rw-r--r-- | include/linux/cpuhotplug.h | 1 | ||||
| -rw-r--r-- | include/linux/relay.h | 6 | ||||
| -rw-r--r-- | kernel/cpu.c | 6 | ||||
| -rw-r--r-- | kernel/relay.c | 58 |
4 files changed, 26 insertions, 45 deletions
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 9e6d10786e29..4c79f40fcebc 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -21,6 +21,7 @@ enum cpuhp_state { CPUHP_PROFILE_PREPARE, CPUHP_X2APIC_PREPARE, CPUHP_SMPCFD_PREPARE, + CPUHP_RELAY_PREPARE, CPUHP_RCUTREE_PREP, CPUHP_NOTIFY_PREPARE, CPUHP_TIMERS_DEAD, diff --git a/include/linux/relay.h b/include/linux/relay.h index eb295e373b90..ecbb34a382b8 100644 --- a/include/linux/relay.h +++ b/include/linux/relay.h @@ -288,5 +288,11 @@ static inline void subbuf_start_reserve(struct rchan_buf *buf, */ extern const struct file_operations relay_file_operations; +#ifdef CONFIG_RELAY +int relay_prepare_cpu(unsigned int cpu); +#else +#define relay_prepare_cpu NULL +#endif + #endif /* _LINUX_RELAY_H */ diff --git a/kernel/cpu.c b/kernel/cpu.c index d14ae4438e8e..0c0d4b2ddd1c 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -23,6 +23,7 @@ #include <linux/tick.h> #include <linux/irq.h> #include <linux/smpboot.h> +#include <linux/relay.h> #include <trace/events/power.h> #define CREATE_TRACE_POINTS @@ -1272,6 +1273,11 @@ static struct cpuhp_step cpuhp_bp_states[] = { .startup.single = smpcfd_prepare_cpu, .teardown.single = smpcfd_dead_cpu, }, + [CPUHP_RELAY_PREPARE] = { + .name = "relay:prepare", + .startup.single = relay_prepare_cpu, + .teardown.single = NULL, + }, [CPUHP_RCUTREE_PREP] = { .name = "RCU/tree:prepare", .startup.single = rcutree_prepare_cpu, diff --git a/kernel/relay.c b/kernel/relay.c index ed157378f6cb..fc9b4a4af463 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -513,48 +513,25 @@ static void setup_callbacks(struct rchan *chan, chan->cb = cb; } -/** - * relay_hotcpu_callback - CPU hotplug callback - * @nb: notifier block - * @action: hotplug action to take - * @hcpu: CPU number - * - * Returns the success/failure of the operation. (%NOTIFY_OK, %NOTIFY_BAD) - */ -static int relay_hotcpu_callback(struct notifier_block *nb, - unsigned long action, - void *hcpu) +int relay_prepare_cpu(unsigned int cpu) { - unsigned int hotcpu = (unsigned long)hcpu; struct rchan *chan; struct rchan_buf *buf; - switch(action) { - case CPU_UP_PREPARE: - case CPU_UP_PREPARE_FROZEN: - mutex_lock(&relay_channels_mutex); - list_for_each_entry(chan, &relay_channels, list) { - if ((buf = *per_cpu_ptr(chan->buf, hotcpu))) - continue; - buf = relay_open_buf(chan, hotcpu); - if (!buf) { - printk(KERN_ERR - "relay_hotcpu_callback: cpu %d buffer " - "creation failed\n", hotcpu); - mutex_unlock(&relay_channels_mutex); - return notifier_from_errno(-ENOMEM); - } - *per_cpu_ptr(chan->buf, hotcpu) = buf; + mutex_lock(&relay_channels_mutex); + list_for_each_entry(chan, &relay_channels, list) { + if ((buf = *per_cpu_ptr(chan->buf, cpu))) + continue; + buf = relay_open_buf(chan, cpu); + if (!buf) { + pr_err("relay: cpu %d buffer creation failed\n", cpu); + mutex_unlock(&relay_channels_mutex); + return -ENOMEM; } - mutex_unlock(&relay_channels_mutex); - break; - case CPU_DEAD: - case CPU_DEAD_FROZEN: - /* No need to flush the cpu : will be flushed upon - * final relay_flush() call. */ - break; + *per_cpu_ptr(chan->buf, cpu) = buf; } - return NOTIFY_OK; + mutex_unlock(&relay_channels_mutex); + return 0; } /** @@ -1387,12 +1364,3 @@ const struct file_operations relay_file_operations = { .splice_read = relay_file_splice_read, }; EXPORT_SYMBOL_GPL(relay_file_operations); - -static __init int relay_init(void) -{ - - hotcpu_notifier(relay_hotcpu_callback, 0); - return 0; -} - -early_initcall(relay_init); |