Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b3fa6417 authored by Matthew Wilcox's avatar Matthew Wilcox
Browse files

ppc: Convert mmu context allocation to new IDA API 



ida_alloc_range is the perfect fit for this use case.  Eliminates
a custom spinlock, a call to ida_pre_get and a local check for the
allocated ID exceeding a maximum.

Signed-off-by: default avatarMatthew Wilcox <willy@infradead.org>
Reviewed-by: default avatarNicholas Piggin <npiggin@gmail.com>
parent 6e77cc47

arch/powerpc/mm/mmu_context_book3s64.c

+4 −40
Original line number Diff line number Diff line
@@ -26,48 +26,16 @@ 
#include <asm/mmu_context.h>

#include <asm/pgalloc.h>



static DEFINE_SPINLOCK(mmu_context_lock);

static DEFINE_IDA(mmu_context_ida);



static int alloc_context_id(int min_id, int max_id)

{

	int index, err;



again:

	if (!ida_pre_get(&mmu_context_ida, GFP_KERNEL))

		return -ENOMEM;



	spin_lock(&mmu_context_lock);

	err = ida_get_new_above(&mmu_context_ida, min_id, &index);

	spin_unlock(&mmu_context_lock);



	if (err == -EAGAIN)

		goto again;

	else if (err)

		return err;



	if (index > max_id) {

		spin_lock(&mmu_context_lock);

		ida_remove(&mmu_context_ida, index);

		spin_unlock(&mmu_context_lock);

		return -ENOMEM;

	}



	return index;

	return ida_alloc_range(&mmu_context_ida, min_id, max_id, GFP_KERNEL);

}



void hash__reserve_context_id(int id)

{

	int rc, result = 0;



	do {

		if (!ida_pre_get(&mmu_context_ida, GFP_KERNEL))

			break;



		spin_lock(&mmu_context_lock);

		rc = ida_get_new_above(&mmu_context_ida, id, &result);

		spin_unlock(&mmu_context_lock);

	} while (rc == -EAGAIN);

	int result = ida_alloc_range(&mmu_context_ida, id, id, GFP_KERNEL);



	WARN(result != id, "mmu: Failed to reserve context id %d (rc %d)\n", id, result);

}
@@ -172,9 +140,7 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm) 


void __destroy_context(int context_id)

{

	spin_lock(&mmu_context_lock);

	ida_remove(&mmu_context_ida, context_id);

	spin_unlock(&mmu_context_lock);

	ida_free(&mmu_context_ida, context_id);

}

EXPORT_SYMBOL_GPL(__destroy_context);
@@ -182,13 +148,11 @@ static void destroy_contexts(mm_context_t *ctx) 
{

	int index, context_id;



	spin_lock(&mmu_context_lock);

	for (index = 0; index < ARRAY_SIZE(ctx->extended_id); index++) {

		context_id = ctx->extended_id[index];

		if (context_id)

			ida_remove(&mmu_context_ida, context_id);

			ida_free(&mmu_context_ida, context_id);

	}

	spin_unlock(&mmu_context_lock);

}



static void pte_frag_destroy(void *pte_frag)