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-rw-r--r--include/linux/smp.h289
1 files changed, 289 insertions, 0 deletions
diff --git a/include/linux/smp.h b/include/linux/smp.h
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index 000000000..a80ab58ae
--- /dev/null
+++ b/include/linux/smp.h
@@ -0,0 +1,289 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_SMP_H
+#define __LINUX_SMP_H
+
+/*
+ * Generic SMP support
+ * Alan Cox. <alan@redhat.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/cpumask.h>
+#include <linux/init.h>
+#include <linux/smp_types.h>
+
+typedef void (*smp_call_func_t)(void *info);
+typedef bool (*smp_cond_func_t)(int cpu, void *info);
+
+/*
+ * structure shares (partial) layout with struct irq_work
+ */
+struct __call_single_data {
+ struct __call_single_node node;
+ smp_call_func_t func;
+ void *info;
+};
+
+#define CSD_INIT(_func, _info) \
+ (struct __call_single_data){ .func = (_func), .info = (_info), }
+
+/* Use __aligned() to avoid to use 2 cache lines for 1 csd */
+typedef struct __call_single_data call_single_data_t
+ __aligned(sizeof(struct __call_single_data));
+
+#define INIT_CSD(_csd, _func, _info) \
+do { \
+ *(_csd) = CSD_INIT((_func), (_info)); \
+} while (0)
+
+/*
+ * Enqueue a llist_node on the call_single_queue; be very careful, read
+ * flush_smp_call_function_queue() in detail.
+ */
+extern void __smp_call_single_queue(int cpu, struct llist_node *node);
+
+/* total number of cpus in this system (may exceed NR_CPUS) */
+extern unsigned int total_cpus;
+
+int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
+ int wait);
+
+void on_each_cpu_cond_mask(smp_cond_func_t cond_func, smp_call_func_t func,
+ void *info, bool wait, const struct cpumask *mask);
+
+int smp_call_function_single_async(int cpu, struct __call_single_data *csd);
+
+/*
+ * Cpus stopping functions in panic. All have default weak definitions.
+ * Architecture-dependent code may override them.
+ */
+void panic_smp_self_stop(void);
+void nmi_panic_self_stop(struct pt_regs *regs);
+void crash_smp_send_stop(void);
+
+/*
+ * Call a function on all processors
+ */
+static inline void on_each_cpu(smp_call_func_t func, void *info, int wait)
+{
+ on_each_cpu_cond_mask(NULL, func, info, wait, cpu_online_mask);
+}
+
+/**
+ * on_each_cpu_mask(): Run a function on processors specified by
+ * cpumask, which may include the local processor.
+ * @mask: The set of cpus to run on (only runs on online subset).
+ * @func: The function to run. This must be fast and non-blocking.
+ * @info: An arbitrary pointer to pass to the function.
+ * @wait: If true, wait (atomically) until function has completed
+ * on other CPUs.
+ *
+ * If @wait is true, then returns once @func has returned.
+ *
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler. The
+ * exception is that it may be used during early boot while
+ * early_boot_irqs_disabled is set.
+ */
+static inline void on_each_cpu_mask(const struct cpumask *mask,
+ smp_call_func_t func, void *info, bool wait)
+{
+ on_each_cpu_cond_mask(NULL, func, info, wait, mask);
+}
+
+/*
+ * Call a function on each processor for which the supplied function
+ * cond_func returns a positive value. This may include the local
+ * processor. May be used during early boot while early_boot_irqs_disabled is
+ * set. Use local_irq_save/restore() instead of local_irq_disable/enable().
+ */
+static inline void on_each_cpu_cond(smp_cond_func_t cond_func,
+ smp_call_func_t func, void *info, bool wait)
+{
+ on_each_cpu_cond_mask(cond_func, func, info, wait, cpu_online_mask);
+}
+
+#ifdef CONFIG_SMP
+
+#include <linux/preempt.h>
+#include <linux/compiler.h>
+#include <linux/thread_info.h>
+#include <asm/smp.h>
+
+/*
+ * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
+ * (defined in asm header):
+ */
+
+/*
+ * stops all CPUs but the current one:
+ */
+extern void smp_send_stop(void);
+
+/*
+ * sends a 'reschedule' event to another CPU:
+ */
+extern void smp_send_reschedule(int cpu);
+
+
+/*
+ * Prepare machine for booting other CPUs.
+ */
+extern void smp_prepare_cpus(unsigned int max_cpus);
+
+/*
+ * Bring a CPU up
+ */
+extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
+
+/*
+ * Final polishing of CPUs
+ */
+extern void smp_cpus_done(unsigned int max_cpus);
+
+/*
+ * Call a function on all other processors
+ */
+void smp_call_function(smp_call_func_t func, void *info, int wait);
+void smp_call_function_many(const struct cpumask *mask,
+ smp_call_func_t func, void *info, bool wait);
+
+int smp_call_function_any(const struct cpumask *mask,
+ smp_call_func_t func, void *info, int wait);
+
+void kick_all_cpus_sync(void);
+void wake_up_all_idle_cpus(void);
+
+/*
+ * Generic and arch helpers
+ */
+void __init call_function_init(void);
+void generic_smp_call_function_single_interrupt(void);
+#define generic_smp_call_function_interrupt \
+ generic_smp_call_function_single_interrupt
+
+/*
+ * Mark the boot cpu "online" so that it can call console drivers in
+ * printk() and can access its per-cpu storage.
+ */
+void smp_prepare_boot_cpu(void);
+
+extern unsigned int setup_max_cpus;
+extern void __init setup_nr_cpu_ids(void);
+extern void __init smp_init(void);
+
+extern int __boot_cpu_id;
+
+static inline int get_boot_cpu_id(void)
+{
+ return __boot_cpu_id;
+}
+
+#else /* !SMP */
+
+static inline void smp_send_stop(void) { }
+
+/*
+ * These macros fold the SMP functionality into a single CPU system
+ */
+#define raw_smp_processor_id() 0
+static inline void up_smp_call_function(smp_call_func_t func, void *info)
+{
+}
+#define smp_call_function(func, info, wait) \
+ (up_smp_call_function(func, info))
+
+static inline void smp_send_reschedule(int cpu) { }
+#define smp_prepare_boot_cpu() do {} while (0)
+#define smp_call_function_many(mask, func, info, wait) \
+ (up_smp_call_function(func, info))
+static inline void call_function_init(void) { }
+
+static inline int
+smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
+ void *info, int wait)
+{
+ return smp_call_function_single(0, func, info, wait);
+}
+
+static inline void kick_all_cpus_sync(void) { }
+static inline void wake_up_all_idle_cpus(void) { }
+
+#ifdef CONFIG_UP_LATE_INIT
+extern void __init up_late_init(void);
+static inline void smp_init(void) { up_late_init(); }
+#else
+static inline void smp_init(void) { }
+#endif
+
+static inline int get_boot_cpu_id(void)
+{
+ return 0;
+}
+
+#endif /* !SMP */
+
+/**
+ * raw_processor_id() - get the current (unstable) CPU id
+ *
+ * For then you know what you are doing and need an unstable
+ * CPU id.
+ */
+
+/**
+ * smp_processor_id() - get the current (stable) CPU id
+ *
+ * This is the normal accessor to the CPU id and should be used
+ * whenever possible.
+ *
+ * The CPU id is stable when:
+ *
+ * - IRQs are disabled;
+ * - preemption is disabled;
+ * - the task is CPU affine.
+ *
+ * When CONFIG_DEBUG_PREEMPT; we verify these assumption and WARN
+ * when smp_processor_id() is used when the CPU id is not stable.
+ */
+
+/*
+ * Allow the architecture to differentiate between a stable and unstable read.
+ * For example, x86 uses an IRQ-safe asm-volatile read for the unstable but a
+ * regular asm read for the stable.
+ */
+#ifndef __smp_processor_id
+#define __smp_processor_id(x) raw_smp_processor_id(x)
+#endif
+
+#ifdef CONFIG_DEBUG_PREEMPT
+ extern unsigned int debug_smp_processor_id(void);
+# define smp_processor_id() debug_smp_processor_id()
+#else
+# define smp_processor_id() __smp_processor_id()
+#endif
+
+#define get_cpu() ({ preempt_disable(); __smp_processor_id(); })
+#define put_cpu() preempt_enable()
+
+/*
+ * Callback to arch code if there's nosmp or maxcpus=0 on the
+ * boot command line:
+ */
+extern void arch_disable_smp_support(void);
+
+extern void arch_thaw_secondary_cpus_begin(void);
+extern void arch_thaw_secondary_cpus_end(void);
+
+void smp_setup_processor_id(void);
+
+int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par,
+ bool phys);
+
+/* SMP core functions */
+int smpcfd_prepare_cpu(unsigned int cpu);
+int smpcfd_dead_cpu(unsigned int cpu);
+int smpcfd_dying_cpu(unsigned int cpu);
+
+#endif /* __LINUX_SMP_H */