mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
![Linus Torvalds](/assets/img/avatar_default.png)
- Optimize the task wakeup CPU selection logic, to improve scalability and reduce wakeup latency spikes - PELT enhancements - CFS bandwidth handling fixes - Optimize the wakeup path by remove rq->wake_list and replacing it with ->ttwu_pending - Optimize IPI cross-calls by making flush_smp_call_function_queue() process sync callbacks first. - Misc fixes and enhancements. Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl7WPL0RHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1i0ThAAs0fbvMzNJ5SWFdwOQ4KZIlA+Im4dEBMK sx/XAZqa/hGxvkm1jS0RDVQl1V1JdOlru5UF4C42ctnAFGtBBHDriO5rn9oCpkSw DAoLc4eZqzldIXN6sDZ0xMtC14Eu15UAP40OyM4qxBc4GqGlOnnale6Vhn+n+pLQ jAuZlMJIkmmzeA6cuvtultevrVh+QUqJ/5oNUANlTER4OM48umjr5rNTOb8cIW53 9K3vbS3nmqSvJuIyqfRFoMy5GFM6+Jj2+nYuq8aTuYLEtF4qqWzttS3wBzC9699g XYRKILkCK8ZP4RB5Ps/DIKj6maZGZoICBxTJEkIgXujJlxlKKTD3mddk+0LBXChW Ijznanxn67akoAFpqi/Dnkhieg7cUrE9v1OPRS2J0xy550synSPFcSgOK3viizga iqbjptY4scUWkCwHQNjABerxc7MWzrwbIrRt+uNvCaqJLweUh0GnEcV5va8R+4I8 K20XwOdrzuPLo5KdDWA/BKOEv49guHZDvoykzlwMlR3gFfwHS/UsjzmSQIWK3gZG 9OMn8ibO2f1OzhRcEpDLFzp7IIj6NJmPFVSW+7xHyL9/vTveUx3ZXPLteb2qxJVP BYPsduVx8YeGRBlLya0PJriB23ajQr0lnHWo15g0uR9o/0Ds1ephcymiF3QJmCaA To3CyIuQN8M= =C2OP -----END PGP SIGNATURE----- Merge tag 'sched-core-2020-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The changes in this cycle are: - Optimize the task wakeup CPU selection logic, to improve scalability and reduce wakeup latency spikes - PELT enhancements - CFS bandwidth handling fixes - Optimize the wakeup path by remove rq->wake_list and replacing it with ->ttwu_pending - Optimize IPI cross-calls by making flush_smp_call_function_queue() process sync callbacks first. - Misc fixes and enhancements" * tag 'sched-core-2020-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) irq_work: Define irq_work_single() on !CONFIG_IRQ_WORK too sched/headers: Split out open-coded prototypes into kernel/sched/smp.h sched: Replace rq::wake_list sched: Add rq::ttwu_pending irq_work, smp: Allow irq_work on call_single_queue smp: Optimize send_call_function_single_ipi() smp: Move irq_work_run() out of flush_smp_call_function_queue() smp: Optimize flush_smp_call_function_queue() sched: Fix smp_call_function_single_async() usage for ILB sched/core: Offload wakee task activation if it the wakee is descheduling sched/core: Optimize ttwu() spinning on p->on_cpu sched: Defend cfs and rt bandwidth quota against overflow sched/cpuacct: Fix charge cpuacct.usage_sys sched/fair: Replace zero-length array with flexible-array sched/pelt: Sync util/runnable_sum with PELT window when propagating sched/cpuacct: Use __this_cpu_add() instead of this_cpu_ptr() sched/fair: Optimize enqueue_task_fair() sched: Make scheduler_ipi inline sched: Clean up scheduler_ipi() sched/core: Simplify sched_init() ...
265 lines
6.4 KiB
C
265 lines
6.4 KiB
C
/* 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/llist.h>
|
|
|
|
typedef void (*smp_call_func_t)(void *info);
|
|
typedef bool (*smp_cond_func_t)(int cpu, void *info);
|
|
|
|
enum {
|
|
CSD_FLAG_LOCK = 0x01,
|
|
|
|
/* IRQ_WORK_flags */
|
|
|
|
CSD_TYPE_ASYNC = 0x00,
|
|
CSD_TYPE_SYNC = 0x10,
|
|
CSD_TYPE_IRQ_WORK = 0x20,
|
|
CSD_TYPE_TTWU = 0x30,
|
|
CSD_FLAG_TYPE_MASK = 0xF0,
|
|
};
|
|
|
|
/*
|
|
* structure shares (partial) layout with struct irq_work
|
|
*/
|
|
struct __call_single_data {
|
|
struct llist_node llist;
|
|
unsigned int flags;
|
|
smp_call_func_t func;
|
|
void *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));
|
|
|
|
/*
|
|
* 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);
|
|
|
|
/*
|
|
* Call a function on all processors
|
|
*/
|
|
void on_each_cpu(smp_call_func_t func, void *info, int wait);
|
|
|
|
/*
|
|
* Call a function on processors specified by mask, which might include
|
|
* the local one.
|
|
*/
|
|
void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
|
|
void *info, bool wait);
|
|
|
|
/*
|
|
* Call a function on each processor for which the supplied function
|
|
* cond_func returns a positive value. This may include the local
|
|
* processor.
|
|
*/
|
|
void on_each_cpu_cond(smp_cond_func_t cond_func, smp_call_func_t func,
|
|
void *info, bool 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, call_single_data_t *csd);
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
#include <linux/preempt.h>
|
|
#include <linux/kernel.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 */
|