diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2025-11-19 20:27:03 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2025-11-25 21:45:40 +0300 |
| commit | 539115f08cf850b9fdc6526b31da0839ff6c1631 (patch) | |
| tree | 4de423fb43b543bd798c8de23be934bbbaace9aa /include/linux | |
| parent | 35a5c37cb9f1f947dff18e7cfc75a8cfcfd557ca (diff) | |
| download | linux-539115f08cf850b9fdc6526b31da0839ff6c1631.tar.xz | |
sched/mmcid: Convert mm CID mask to a bitmap
This is truly a bitmap and just conveniently uses a cpumask because the
maximum size of the bitmap is nr_cpu_ids.
But that prevents to do searches for a zero bit in a limited range, which
is helpful to provide an efficient mechanism to consolidate the CID space
when the number of users decreases.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Link: https://patch.msgid.link/20251119172549.642866767@linutronix.de
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/mm_types.h | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 67a7bdf772f7..bafb81b33922 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -1342,13 +1342,13 @@ static inline cpumask_t *mm_cpus_allowed(struct mm_struct *mm) } /* Accessor for struct mm_struct's cidmask. */ -static inline cpumask_t *mm_cidmask(struct mm_struct *mm) +static inline unsigned long *mm_cidmask(struct mm_struct *mm) { unsigned long cid_bitmap = (unsigned long)mm_cpus_allowed(mm); /* Skip mm_cpus_allowed */ cid_bitmap += cpumask_size(); - return (struct cpumask *)cid_bitmap; + return (unsigned long *)cid_bitmap; } static inline void mm_init_cid(struct mm_struct *mm, struct task_struct *p) @@ -1363,7 +1363,7 @@ static inline void mm_init_cid(struct mm_struct *mm, struct task_struct *p) mm->mm_cid.nr_cpus_allowed = p->nr_cpus_allowed; raw_spin_lock_init(&mm->mm_cid.lock); cpumask_copy(mm_cpus_allowed(mm), &p->cpus_mask); - cpumask_clear(mm_cidmask(mm)); + bitmap_zero(mm_cidmask(mm), num_possible_cpus()); } static inline int mm_alloc_cid_noprof(struct mm_struct *mm, struct task_struct *p) @@ -1384,7 +1384,8 @@ static inline void mm_destroy_cid(struct mm_struct *mm) static inline unsigned int mm_cid_size(void) { - return 2 * cpumask_size(); /* mm_cpus_allowed(), mm_cidmask(). */ + /* mm_cpus_allowed(), mm_cidmask(). */ + return cpumask_size() + bitmap_size(num_possible_cpus()); } #else /* CONFIG_SCHED_MM_CID */ |