Commit 09dc3972 authored by Thomas Richter's avatar Thomas Richter Committed by Heiko Carstens
Browse files

s390/pai_crypto: Consolidate PAI crypto allocation and cleanup paths 



Introduce paicrypt_free() to centralize memory release for per-CPU
maps and remove duplicated free logic. Replace paicrypt_busy() with
paicrypt_alloc_cpu() returning int error codes instead of ERR_PTR,
and adjust callers accordingly. System-wide allocation now uses
paicrypt_alloc() with consistent error handling. Memory allocation
and free management is now identical to PMU pai_ext.

Reference counting and root anchor management remain unchanged.
Debug output in the destroy path is dropped.

Signed-off-by: default avatarThomas Richter <tmricht@linux.ibm.com>
Tested-by: default avatarJan Polensky <japo@linux.ibm.com>
Reviewed-by: default avatarJan Polensky <japo@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent 9daa5a87

arch/s390/kernel/perf_pai_crypto.c

+44 −62
Original line number Diff line number Diff line
@@ -80,6 +80,15 @@ static int paicrypt_root_alloc(void) 
/* Release the PMU if event is the last perf event */

static DEFINE_MUTEX(pai_reserve_mutex);



/* Free all memory allocated for event counting/sampling setup */

static void paicrypt_free(struct paicrypt_mapptr *mp)

{

	free_page((unsigned long)mp->mapptr->page);

	kvfree(mp->mapptr->save);

	kfree(mp->mapptr);

	mp->mapptr = NULL;

}



/* Adjust usage counters and remove allocated memory when all users are

 * gone.

 */
@@ -93,15 +102,8 @@ static void paicrypt_event_destroy_cpu(struct perf_event *event, int cpu) 
			    "refcnt %u\n", __func__, event->attr.config,

			    event->cpu, cpump->active_events,

			    refcount_read(&cpump->refcnt));

	if (refcount_dec_and_test(&cpump->refcnt)) {

		debug_sprintf_event(cfm_dbg, 4, "%s page %#lx save %p\n",

				    __func__, (unsigned long)cpump->page,

				    cpump->save);

		free_page((unsigned long)cpump->page);

		kvfree(cpump->save);

		kfree(cpump);

		mp->mapptr = NULL;

	}

	if (refcount_dec_and_test(&cpump->refcnt))

		paicrypt_free(mp);

	paicrypt_root_free();

	mutex_unlock(&pai_reserve_mutex);

}
@@ -175,14 +177,13 @@ static u64 paicrypt_getall(struct perf_event *event) 
 *

 * Allocate the memory for the event.

 */

static struct paicrypt_map *paicrypt_busy(struct perf_event *event, int cpu)

static int paicrypt_alloc_cpu(struct perf_event *event, int cpu)

{

	struct paicrypt_map *cpump = NULL;

	struct paicrypt_mapptr *mp;

	int rc;



	mutex_lock(&pai_reserve_mutex);



	/* Allocate root node */

	rc = paicrypt_root_alloc();

	if (rc)
@@ -192,58 +193,44 @@ static struct paicrypt_map *paicrypt_busy(struct perf_event *event, int cpu) 
	mp = per_cpu_ptr(paicrypt_root.mapptr, cpu);

	cpump = mp->mapptr;

	if (!cpump) {			/* Paicrypt_map allocated? */

		cpump = kzalloc(sizeof(*cpump), GFP_KERNEL);

		if (!cpump) {

		rc = -ENOMEM;

			goto free_root;

		}

		INIT_LIST_HEAD(&cpump->syswide_list);

	}



		cpump = kzalloc(sizeof(*cpump), GFP_KERNEL);

		if (!cpump)

			goto undo;

		/* Allocate memory for counter page and counter extraction.

		 * Only the first counting event has to allocate a page.

		 */

	if (cpump->page) {

		refcount_inc(&cpump->refcnt);

		goto unlock;

	}



	rc = -ENOMEM;

		mp->mapptr = cpump;

		cpump->page = (unsigned long *)get_zeroed_page(GFP_KERNEL);

	if (!cpump->page)

		goto free_paicrypt_map;

		cpump->save = kvmalloc_array(paicrypt_cnt + 1,

				     sizeof(struct pai_userdata), GFP_KERNEL);

	if (!cpump->save) {

		free_page((unsigned long)cpump->page);

		cpump->page = NULL;

		goto free_paicrypt_map;

					     sizeof(struct pai_userdata),

					     GFP_KERNEL);

		if (!cpump->page || !cpump->save) {

			paicrypt_free(mp);

			goto undo;

		}



	/* Set mode and reference count */

	rc = 0;

		INIT_LIST_HEAD(&cpump->syswide_list);

		refcount_set(&cpump->refcnt, 1);

	mp->mapptr = cpump;

	debug_sprintf_event(cfm_dbg, 5, "%s users %d refcnt %u page %#lx "

			    "save %p rc %d\n", __func__, cpump->active_events,

			    refcount_read(&cpump->refcnt),

			    (unsigned long)cpump->page, cpump->save, rc);

	goto unlock;

		rc = 0;

	} else {

		refcount_inc(&cpump->refcnt);

	}



free_paicrypt_map:

	/* Undo memory allocation */

	kfree(cpump);

	mp->mapptr = NULL;

free_root:

undo:

	if (rc) {

		/* Error in allocation of event, decrement anchor. Since

		 * the event in not created, its destroy() function is never

		 * invoked. Adjust the reference counter for the anchor.

		 */

		paicrypt_root_free();

	}

unlock:

	mutex_unlock(&pai_reserve_mutex);

	return rc ? ERR_PTR(rc) : cpump;

	return rc;

}



static int paicrypt_event_init_all(struct perf_event *event)

static int paicrypt_alloc(struct perf_event *event)

{

	struct paicrypt_map *cpump;

	struct cpumask *maskptr;

	int cpu, rc = -ENOMEM;
@@ -252,12 +239,11 @@ static int paicrypt_event_init_all(struct perf_event *event) 
		goto out;



	for_each_online_cpu(cpu) {

		cpump = paicrypt_busy(event, cpu);

		if (IS_ERR(cpump)) {

		rc = paicrypt_alloc_cpu(event, cpu);

		if (rc) {

			for_each_cpu(cpu, maskptr)

				paicrypt_event_destroy_cpu(event, cpu);

			kfree(maskptr);

			rc = PTR_ERR(cpump);

			goto out;

		}

		cpumask_set_cpu(cpu, maskptr);
@@ -279,7 +265,6 @@ static int paicrypt_event_init_all(struct perf_event *event) 
static int paicrypt_event_init(struct perf_event *event)

{

	struct perf_event_attr *a = &event->attr;

	struct paicrypt_map *cpump;

	int rc = 0;



	/* PAI crypto PMU registered as PERF_TYPE_RAW, check event type */
@@ -301,13 +286,10 @@ static int paicrypt_event_init(struct perf_event *event) 
		}

	}



	if (event->cpu >= 0) {

		cpump = paicrypt_busy(event, event->cpu);

		if (IS_ERR(cpump))

			rc = PTR_ERR(cpump);

	} else {

		rc = paicrypt_event_init_all(event);

	}

	if (event->cpu >= 0)

		rc = paicrypt_alloc_cpu(event, event->cpu);

	else

		rc = paicrypt_alloc(event);

	if (rc) {

		free_page(PAI_SAVE_AREA(event));

		goto out;