From 83606043960b323332d2dd3b5f62a8026ef712a2 Mon Sep 17 00:00:00 2001 From: Tashfin Shakeer Rhythm Date: Tue, 1 Mar 2022 02:21:31 +0600 Subject: [PATCH] Revert "mm: Perform PID map reads on the little CPU cluster" Our little cores are not that fast; moreover, they are inefficient. Therefore, it's not a good idea to perform PID map reads on this cluster. We can presumably get better jitter by doing this. This reverts commit d46ff2c40d6e5539925c4ad7bdf13921ac91928c. Signed-off-by: Tashfin Shakeer Rhythm --- fs/proc/internal.h | 1 - fs/proc/task_mmu.c | 6 ------ 2 files changed, 7 deletions(-) diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 041af21ebc0bc..e05deaee80d93 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -298,7 +298,6 @@ struct proc_maps_private { #ifdef CONFIG_NUMA struct mempolicy *task_mempolicy; #endif - unsigned long old_cpus_allowed; } __randomize_layout; struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode); diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 2a923a3606f96..b4a6e797dea4c 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -182,9 +182,6 @@ static void vma_stop(struct proc_maps_private *priv) release_task_mempolicy(priv); up_read(&mm->mmap_sem); mmput(mm); - - sched_migrate_to_cpumask_end(to_cpumask(&priv->old_cpus_allowed), - cpu_lp_mask); } static struct vm_area_struct * @@ -221,9 +218,6 @@ static void *m_start(struct seq_file *m, loff_t *ppos) if (!mm || !mmget_not_zero(mm)) return NULL; - sched_migrate_to_cpumask_start(to_cpumask(&priv->old_cpus_allowed), - cpu_lp_mask); - if (down_read_killable(&mm->mmap_sem)) { mmput(mm); return ERR_PTR(-EINTR);