diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/irq_work.h | 9 | ||||
| -rw-r--r-- | include/linux/sched.h | 11 | ||||
| -rw-r--r-- | include/linux/sched/mm.h | 2 | ||||
| -rw-r--r-- | include/linux/sched/topology.h | 29 | ||||
| -rw-r--r-- | include/linux/smp.h | 24 | ||||
| -rw-r--r-- | include/linux/swait.h | 23 |
6 files changed, 62 insertions, 36 deletions
diff --git a/include/linux/irq_work.h b/include/linux/irq_work.h index 3b752e80c017..2735da5f839e 100644 --- a/include/linux/irq_work.h +++ b/include/linux/irq_work.h @@ -13,6 +13,8 @@ * busy NULL, 2 -> {free, claimed} : callback in progress, can be claimed */ +/* flags share CSD_FLAG_ space */ + #define IRQ_WORK_PENDING BIT(0) #define IRQ_WORK_BUSY BIT(1) @@ -23,9 +25,12 @@ #define IRQ_WORK_CLAIMED (IRQ_WORK_PENDING | IRQ_WORK_BUSY) +/* + * structure shares layout with single_call_data_t. + */ struct irq_work { - atomic_t flags; struct llist_node llnode; + atomic_t flags; void (*func)(struct irq_work *); }; @@ -53,9 +58,11 @@ void irq_work_sync(struct irq_work *work); void irq_work_run(void); bool irq_work_needs_cpu(void); +void irq_work_single(void *arg); #else static inline bool irq_work_needs_cpu(void) { return false; } static inline void irq_work_run(void) { } +static inline void irq_work_single(void *arg) { } #endif #endif /* _LINUX_IRQ_WORK_H */ diff --git a/include/linux/sched.h b/include/linux/sched.h index 33bb7c539246..12938d438d69 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -654,6 +654,7 @@ struct task_struct { #ifdef CONFIG_SMP struct llist_node wake_entry; + unsigned int wake_entry_type; int on_cpu; #ifdef CONFIG_THREAD_INFO_IN_TASK /* Current CPU: */ @@ -1730,7 +1731,15 @@ extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk); }) #ifdef CONFIG_SMP -void scheduler_ipi(void); +static __always_inline void scheduler_ipi(void) +{ + /* + * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting + * TIF_NEED_RESCHED remotely (for the first time) will also send + * this IPI. + */ + preempt_fold_need_resched(); +} extern unsigned long wait_task_inactive(struct task_struct *, long match_state); #else static inline void scheduler_ipi(void) { } diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index c49257a3b510..a132d875d351 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -49,6 +49,8 @@ static inline void mmdrop(struct mm_struct *mm) __mmdrop(mm); } +void mmdrop(struct mm_struct *mm); + /* * This has to be called after a get_task_mm()/mmget_not_zero() * followed by taking the mmap_sem for writing before modifying the diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h index 95253ad792b0..fb11091129b3 100644 --- a/include/linux/sched/topology.h +++ b/include/linux/sched/topology.h @@ -11,21 +11,20 @@ */ #ifdef CONFIG_SMP -#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ -#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ -#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ -#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ -#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ -#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ -#define SD_ASYM_CPUCAPACITY 0x0040 /* Domain members have different CPU capacities */ -#define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share CPU capacity */ -#define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ -#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share CPU pkg resources */ -#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ -#define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ -#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ -#define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ -#define SD_NUMA 0x4000 /* cross-node balancing */ +#define SD_BALANCE_NEWIDLE 0x0001 /* Balance when about to become idle */ +#define SD_BALANCE_EXEC 0x0002 /* Balance on exec */ +#define SD_BALANCE_FORK 0x0004 /* Balance on fork, clone */ +#define SD_BALANCE_WAKE 0x0008 /* Balance on wakeup */ +#define SD_WAKE_AFFINE 0x0010 /* Wake task to waking CPU */ +#define SD_ASYM_CPUCAPACITY 0x0020 /* Domain members have different CPU capacities */ +#define SD_SHARE_CPUCAPACITY 0x0040 /* Domain members share CPU capacity */ +#define SD_SHARE_POWERDOMAIN 0x0080 /* Domain members share power domain */ +#define SD_SHARE_PKG_RESOURCES 0x0100 /* Domain members share CPU pkg resources */ +#define SD_SERIALIZE 0x0200 /* Only a single load balancing instance */ +#define SD_ASYM_PACKING 0x0400 /* Place busy groups earlier in the domain */ +#define SD_PREFER_SIBLING 0x0800 /* Prefer to place tasks in a sibling domain */ +#define SD_OVERLAP 0x1000 /* sched_domains of this level overlap */ +#define SD_NUMA 0x2000 /* cross-node balancing */ #ifdef CONFIG_SCHED_SMT static inline int cpu_smt_flags(void) diff --git a/include/linux/smp.h b/include/linux/smp.h index 04019872c7bc..7ee202ad21a6 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -16,17 +16,39 @@ 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; - unsigned int flags; }; /* 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; diff --git a/include/linux/swait.h b/include/linux/swait.h index 73e06e9986d4..6a8c22b8c2a5 100644 --- a/include/linux/swait.h +++ b/include/linux/swait.h @@ -9,23 +9,10 @@ #include <asm/current.h> /* - * BROKEN wait-queues. - * - * These "simple" wait-queues are broken garbage, and should never be - * used. The comments below claim that they are "similar" to regular - * wait-queues, but the semantics are actually completely different, and - * every single user we have ever had has been buggy (or pointless). - * - * A "swake_up_one()" only wakes up _one_ waiter, which is not at all what - * "wake_up()" does, and has led to problems. In other cases, it has - * been fine, because there's only ever one waiter (kvm), but in that - * case gthe whole "simple" wait-queue is just pointless to begin with, - * since there is no "queue". Use "wake_up_process()" with a direct - * pointer instead. - * - * While these are very similar to regular wait queues (wait.h) the most - * important difference is that the simple waitqueue allows for deterministic - * behaviour -- IOW it has strictly bounded IRQ and lock hold times. + * Simple waitqueues are semantically very different to regular wait queues + * (wait.h). The most important difference is that the simple waitqueue allows + * for deterministic behaviour -- IOW it has strictly bounded IRQ and lock hold + * times. * * Mainly, this is accomplished by two things. Firstly not allowing swake_up_all * from IRQ disabled, and dropping the lock upon every wakeup, giving a higher @@ -39,7 +26,7 @@ * sleeper state. * * - the !exclusive mode; because that leads to O(n) wakeups, everything is - * exclusive. + * exclusive. As such swake_up_one will only ever awake _one_ waiter. * * - custom wake callback functions; because you cannot give any guarantees * about random code. This also allows swait to be used in RT, such that |