diff options
Diffstat (limited to 'include/linux/sched/mm.h')
| -rw-r--r-- | include/linux/sched/mm.h | 207 |
1 files changed, 151 insertions, 56 deletions
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 2a243616f222..0e1d73955fa5 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -8,7 +8,7 @@ #include <linux/mm_types.h> #include <linux/gfp.h> #include <linux/sync_core.h> -#include <linux/ioasid.h> +#include <linux/sched/coredump.h> /* * Routines for handling mm_structs @@ -37,6 +37,11 @@ static inline void mmgrab(struct mm_struct *mm) atomic_inc(&mm->mm_count); } +static inline void smp_mb__after_mmgrab(void) +{ + smp_mb__after_atomic(); +} + extern void __mmdrop(struct mm_struct *mm); static inline void mmdrop(struct mm_struct *mm) @@ -79,6 +84,34 @@ static inline void mmdrop_sched(struct mm_struct *mm) } #endif +/* Helpers for lazy TLB mm refcounting */ +static inline void mmgrab_lazy_tlb(struct mm_struct *mm) +{ + if (IS_ENABLED(CONFIG_MMU_LAZY_TLB_REFCOUNT)) + mmgrab(mm); +} + +static inline void mmdrop_lazy_tlb(struct mm_struct *mm) +{ + if (IS_ENABLED(CONFIG_MMU_LAZY_TLB_REFCOUNT)) { + mmdrop(mm); + } else { + /* + * mmdrop_lazy_tlb must provide a full memory barrier, see the + * membarrier comment finish_task_switch which relies on this. + */ + smp_mb(); + } +} + +static inline void mmdrop_lazy_tlb_sched(struct mm_struct *mm) +{ + if (IS_ENABLED(CONFIG_MMU_LAZY_TLB_REFCOUNT)) + mmdrop_sched(mm); + else + smp_mb(); /* see mmdrop_lazy_tlb() above */ +} + /** * mmget() - Pin the address space associated with a &struct mm_struct. * @mm: The address space to pin. @@ -107,7 +140,7 @@ static inline bool mmget_not_zero(struct mm_struct *mm) /* mmput gets rid of the mappings and all user-space */ extern void mmput(struct mm_struct *); -#ifdef CONFIG_MMU +#if defined(CONFIG_MMU) || defined(CONFIG_FUTEX_PRIVATE_HASH) /* same as above but performs the slow path from the async context. Can * be called from the atomic context as well */ @@ -145,26 +178,39 @@ static inline void mm_update_next_owner(struct mm_struct *mm) #endif extern void arch_pick_mmap_layout(struct mm_struct *mm, - struct rlimit *rlim_stack); -extern unsigned long -arch_get_unmapped_area(struct file *, unsigned long, unsigned long, - unsigned long, unsigned long); -extern unsigned long + const struct rlimit *rlim_stack); + +unsigned long +arch_get_unmapped_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t vm_flags); +unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, - unsigned long len, unsigned long pgoff, - unsigned long flags); + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t); + +unsigned long mm_get_unmapped_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags); + +unsigned long mm_get_unmapped_area_vmflags(struct file *filp, + unsigned long addr, + unsigned long len, + unsigned long pgoff, + unsigned long flags, + vm_flags_t vm_flags); unsigned long generic_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags); + unsigned long flags, vm_flags_t vm_flags); unsigned long generic_get_unmapped_area_topdown(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, - unsigned long flags); + unsigned long flags, vm_flags_t vm_flags); #else static inline void arch_pick_mmap_layout(struct mm_struct *mm, - struct rlimit *rlim_stack) {} + const struct rlimit *rlim_stack) {} #endif static inline bool in_vfork(struct task_struct *tsk) @@ -271,10 +317,31 @@ static inline void might_alloc(gfp_t gfp_mask) fs_reclaim_acquire(gfp_mask); fs_reclaim_release(gfp_mask); + if (current->flags & PF_MEMALLOC) + return; + might_sleep_if(gfpflags_allow_blocking(gfp_mask)); } /** + * memalloc_flags_save - Add a PF_* flag to current->flags, save old value + * + * This allows PF_* flags to be conveniently added, irrespective of current + * value, and then the old version restored with memalloc_flags_restore(). + */ +static inline unsigned memalloc_flags_save(unsigned flags) +{ + unsigned oldflags = ~current->flags & flags; + current->flags |= flags; + return oldflags; +} + +static inline void memalloc_flags_restore(unsigned flags) +{ + current->flags &= ~flags; +} + +/** * memalloc_noio_save - Marks implicit GFP_NOIO allocation scope. * * This functions marks the beginning of the GFP_NOIO allocation scope. @@ -283,13 +350,12 @@ static inline void might_alloc(gfp_t gfp_mask) * point of view. Use memalloc_noio_restore to end the scope with flags * returned by this function. * - * This function is safe to be used from any context. + * Context: This function is safe to be used from any context. + * Return: The saved flags to be passed to memalloc_noio_restore. */ static inline unsigned int memalloc_noio_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC_NOIO; - current->flags |= PF_MEMALLOC_NOIO; - return flags; + return memalloc_flags_save(PF_MEMALLOC_NOIO); } /** @@ -302,7 +368,7 @@ static inline unsigned int memalloc_noio_save(void) */ static inline void memalloc_noio_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; + memalloc_flags_restore(flags); } /** @@ -314,13 +380,12 @@ static inline void memalloc_noio_restore(unsigned int flags) * point of view. Use memalloc_nofs_restore to end the scope with flags * returned by this function. * - * This function is safe to be used from any context. + * Context: This function is safe to be used from any context. + * Return: The saved flags to be passed to memalloc_nofs_restore. */ static inline unsigned int memalloc_nofs_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC_NOFS; - current->flags |= PF_MEMALLOC_NOFS; - return flags; + return memalloc_flags_save(PF_MEMALLOC_NOFS); } /** @@ -333,32 +398,76 @@ static inline unsigned int memalloc_nofs_save(void) */ static inline void memalloc_nofs_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC_NOFS) | flags; + memalloc_flags_restore(flags); } +/** + * memalloc_noreclaim_save - Marks implicit __GFP_MEMALLOC scope. + * + * This function marks the beginning of the __GFP_MEMALLOC allocation scope. + * All further allocations will implicitly add the __GFP_MEMALLOC flag, which + * prevents entering reclaim and allows access to all memory reserves. This + * should only be used when the caller guarantees the allocation will allow more + * memory to be freed very shortly, i.e. it needs to allocate some memory in + * the process of freeing memory, and cannot reclaim due to potential recursion. + * + * Users of this scope have to be extremely careful to not deplete the reserves + * completely and implement a throttling mechanism which controls the + * consumption of the reserve based on the amount of freed memory. Usage of a + * pre-allocated pool (e.g. mempool) should be always considered before using + * this scope. + * + * Individual allocations under the scope can opt out using __GFP_NOMEMALLOC + * + * Context: This function should not be used in an interrupt context as that one + * does not give PF_MEMALLOC access to reserves. + * See __gfp_pfmemalloc_flags(). + * Return: The saved flags to be passed to memalloc_noreclaim_restore. + */ static inline unsigned int memalloc_noreclaim_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC; - current->flags |= PF_MEMALLOC; - return flags; + return memalloc_flags_save(PF_MEMALLOC); } +/** + * memalloc_noreclaim_restore - Ends the implicit __GFP_MEMALLOC scope. + * @flags: Flags to restore. + * + * Ends the implicit __GFP_MEMALLOC scope started by memalloc_noreclaim_save + * function. Always make sure that the given flags is the return value from the + * pairing memalloc_noreclaim_save call. + */ static inline void memalloc_noreclaim_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC) | flags; + memalloc_flags_restore(flags); } +/** + * memalloc_pin_save - Marks implicit ~__GFP_MOVABLE scope. + * + * This function marks the beginning of the ~__GFP_MOVABLE allocation scope. + * All further allocations will implicitly remove the __GFP_MOVABLE flag, which + * will constraint the allocations to zones that allow long term pinning, i.e. + * not ZONE_MOVABLE zones. + * + * Return: The saved flags to be passed to memalloc_pin_restore. + */ static inline unsigned int memalloc_pin_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC_PIN; - - current->flags |= PF_MEMALLOC_PIN; - return flags; + return memalloc_flags_save(PF_MEMALLOC_PIN); } +/** + * memalloc_pin_restore - Ends the implicit ~__GFP_MOVABLE scope. + * @flags: Flags to restore. + * + * Ends the implicit ~__GFP_MOVABLE scope started by memalloc_pin_save function. + * Always make sure that the given flags is the return value from the pairing + * memalloc_pin_save call. + */ static inline void memalloc_pin_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC_PIN) | flags; + memalloc_flags_restore(flags); } #ifdef CONFIG_MEMCG @@ -371,6 +480,10 @@ DECLARE_PER_CPU(struct mem_cgroup *, int_active_memcg); * __GFP_ACCOUNT allocations till the end of the scope will be charged to the * given memcg. * + * Please, make sure that caller has a reference to the passed memcg structure, + * so its lifetime is guaranteed to exceed the scope between two + * set_active_memcg() calls. + * * NOTE: This function can nest. Users must save the return value and * reset the previous value after their own charging scope is over. */ @@ -420,6 +533,13 @@ enum { static inline void membarrier_mm_sync_core_before_usermode(struct mm_struct *mm) { + /* + * The atomic_read() below prevents CSE. The following should + * help the compiler generate more efficient code on architectures + * where sync_core_before_usermode() is a no-op. + */ + if (!IS_ENABLED(CONFIG_ARCH_HAS_SYNC_CORE_BEFORE_USERMODE)) + return; if (current->mm != mm) return; if (likely(!(atomic_read(&mm->membarrier_state) & @@ -451,29 +571,4 @@ static inline void membarrier_update_current_mm(struct mm_struct *next_mm) } #endif -#ifdef CONFIG_IOMMU_SVA -static inline void mm_pasid_init(struct mm_struct *mm) -{ - mm->pasid = INVALID_IOASID; -} - -/* Associate a PASID with an mm_struct: */ -static inline void mm_pasid_set(struct mm_struct *mm, u32 pasid) -{ - mm->pasid = pasid; -} - -static inline void mm_pasid_drop(struct mm_struct *mm) -{ - if (pasid_valid(mm->pasid)) { - ioasid_free(mm->pasid); - mm->pasid = INVALID_IOASID; - } -} -#else -static inline void mm_pasid_init(struct mm_struct *mm) {} -static inline void mm_pasid_set(struct mm_struct *mm, u32 pasid) {} -static inline void mm_pasid_drop(struct mm_struct *mm) {} -#endif - #endif /* _LINUX_SCHED_MM_H */ |