Commit 923717cb authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar
Browse files

sched/rt, mm: Use CONFIG_PREEMPTION 



CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the pte_unmap_same() and SLUB code over to use CONFIG_PREEMPTION.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarChistoph Lameter <cl@linux.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/20191015191821.11479-26-bigeasy@linutronix.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 94545870

mm/memory.c

+1 −1
Original line number Diff line number Diff line
@@ -2151,7 +2151,7 @@ static inline int pte_unmap_same(struct mm_struct *mm, pmd_t *pmd, 
				pte_t *page_table, pte_t orig_pte)

{

	int same = 1;

#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)

#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPTION)

	if (sizeof(pte_t) > sizeof(unsigned long)) {

		spinlock_t *ptl = pte_lockptr(mm, pmd);

		spin_lock(ptl);

mm/slub.c

+6 −6
Original line number Diff line number Diff line
@@ -1964,7 +1964,7 @@ static void *get_partial(struct kmem_cache *s, gfp_t flags, int node, 
	return get_any_partial(s, flags, c);

}



#ifdef CONFIG_PREEMPT

#ifdef CONFIG_PREEMPTION

/*

 * Calculate the next globally unique transaction for disambiguiation

 * during cmpxchg. The transactions start with the cpu number and are then
@@ -2009,7 +2009,7 @@ static inline void note_cmpxchg_failure(const char *n, 


	pr_info("%s %s: cmpxchg redo ", n, s->name);



#ifdef CONFIG_PREEMPT

#ifdef CONFIG_PREEMPTION

	if (tid_to_cpu(tid) != tid_to_cpu(actual_tid))

		pr_warn("due to cpu change %d -> %d\n",

			tid_to_cpu(tid), tid_to_cpu(actual_tid));
@@ -2637,7 +2637,7 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, 
	unsigned long flags;



	local_irq_save(flags);

#ifdef CONFIG_PREEMPT

#ifdef CONFIG_PREEMPTION

	/*

	 * We may have been preempted and rescheduled on a different

	 * cpu before disabling interrupts. Need to reload cpu area
@@ -2691,13 +2691,13 @@ redo: 
	 * as we end up on the original cpu again when doing the cmpxchg.

	 *

	 * We should guarantee that tid and kmem_cache are retrieved on

	 * the same cpu. It could be different if CONFIG_PREEMPT so we need

	 * the same cpu. It could be different if CONFIG_PREEMPTION so we need

	 * to check if it is matched or not.

	 */

	do {

		tid = this_cpu_read(s->cpu_slab->tid);

		c = raw_cpu_ptr(s->cpu_slab);

	} while (IS_ENABLED(CONFIG_PREEMPT) &&

	} while (IS_ENABLED(CONFIG_PREEMPTION) &&

		 unlikely(tid != READ_ONCE(c->tid)));



	/*
@@ -2971,7 +2971,7 @@ redo: 
	do {

		tid = this_cpu_read(s->cpu_slab->tid);

		c = raw_cpu_ptr(s->cpu_slab);

	} while (IS_ENABLED(CONFIG_PREEMPT) &&

	} while (IS_ENABLED(CONFIG_PREEMPTION) &&

		 unlikely(tid != READ_ONCE(c->tid)));



	/* Same with comment on barrier() in slab_alloc_node() */

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