Re: [PATCH v3 3/9] coresight: change coresight_trace_id_map's lock type to raw_spinlock_t

On Mon, 16 Dec 2024 at 11:50, Yeoreum Yun yeoreum.yun@arm.com wrote:

coresight_trace_id_map->lock can be acquired while coresight devices' drvdata_lock.

But the drvdata_lock can be raw_spinlock_t (i.e) coresight-etm4x.

To address this, change type of coresight_trace_id_map->lock to raw_spinlock_t

Signed-off-by: Yeoreum Yun yeoreum.yun@arm.com

drivers/hwtracing/coresight/coresight-core.c | 2 +- .../hwtracing/coresight/coresight-trace-id.c | 22 +++++++++---------- include/linux/coresight.h | 2 +- 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index ea38ecf26fcb..cc2d87b2f248 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -1164,7 +1164,7 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)

    if (csdev->type == CORESIGHT_DEV_TYPE_SINK ||
        csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) {

•           spin_lock_init(&csdev->perf_sink_id_map.lock);
  

•           raw_spin_lock_init(&csdev->perf_sink_id_map.lock);
            csdev->perf_sink_id_map.cpu_map = alloc_percpu(atomic_t);
            if (!csdev->perf_sink_id_map.cpu_map) {
                    kfree(csdev);
  

diff --git a/drivers/hwtracing/coresight/coresight-trace-id.c b/drivers/hwtracing/coresight/coresight-trace-id.c index d98e12cb30ec..a6531869e9ec 100644 --- a/drivers/hwtracing/coresight/coresight-trace-id.c +++ b/drivers/hwtracing/coresight/coresight-trace-id.c @@ -16,7 +16,7 @@ static DEFINE_PER_CPU(atomic_t, id_map_default_cpu_ids) = ATOMIC_INIT(0); static struct coresight_trace_id_map id_map_default = { .cpu_map = &id_map_default_cpu_ids,

•   .lock = __SPIN_LOCK_UNLOCKED(id_map_default.lock)
  

•   .lock = __RAW_SPIN_LOCK_UNLOCKED(id_map_default.lock)
  

};

/* #define TRACE_ID_DEBUG 1 */ @@ -121,11 +121,11 @@ static void coresight_trace_id_release_all(struct coresight_trace_id_map *id_map unsigned long flags; int cpu;

•   spin_lock_irqsave(&id_map->lock, flags);
  

•   raw_spin_lock_irqsave(&id_map->lock, flags);
    bitmap_zero(id_map->used_ids, CORESIGHT_TRACE_IDS_MAX);
    for_each_possible_cpu(cpu)
            atomic_set(per_cpu_ptr(id_map->cpu_map, cpu), 0);
  

•   spin_unlock_irqrestore(&id_map->lock, flags);
  

•   raw_spin_unlock_irqrestore(&id_map->lock, flags);
    DUMP_ID_MAP(id_map);
  

}

@@ -134,7 +134,7 @@ static int _coresight_trace_id_get_cpu_id(int cpu, struct coresight_trace_id_map unsigned long flags; int id;

•   spin_lock_irqsave(&id_map->lock, flags);
  

•   raw_spin_lock_irqsave(&id_map->lock, flags);
  
    /* check for existing allocation for this CPU */
    id = _coresight_trace_id_read_cpu_id(cpu, id_map);
  

@@ -161,7 +161,7 @@ static int _coresight_trace_id_get_cpu_id(int cpu, struct coresight_trace_id_map atomic_set(per_cpu_ptr(id_map->cpu_map, cpu), id);

get_cpu_id_out_unlock:

•   spin_unlock_irqrestore(&id_map->lock, flags);
  

•   raw_spin_unlock_irqrestore(&id_map->lock, flags);
  
    DUMP_ID_CPU(cpu, id);
    DUMP_ID_MAP(id_map);
  

@@ -178,12 +178,12 @@ static void _coresight_trace_id_put_cpu_id(int cpu, struct coresight_trace_id_ma if (!id) return;

•   spin_lock_irqsave(&id_map->lock, flags);
  

•   raw_spin_lock_irqsave(&id_map->lock, flags);
  
    coresight_trace_id_free(id, id_map);
    atomic_set(per_cpu_ptr(id_map->cpu_map, cpu), 0);
  
  

•   spin_unlock_irqrestore(&id_map->lock, flags);
  

•   raw_spin_unlock_irqrestore(&id_map->lock, flags);
    DUMP_ID_CPU(cpu, id);
    DUMP_ID_MAP(id_map);
  

} @@ -193,10 +193,10 @@ static int coresight_trace_id_map_get_system_id(struct coresight_trace_id_map *i unsigned long flags; int id;

•   spin_lock_irqsave(&id_map->lock, flags);
  

•   raw_spin_lock_irqsave(&id_map->lock, flags);
    /* prefer odd IDs for system components to avoid legacy CPU IDS */
    id = coresight_trace_id_alloc_new_id(id_map, 0, true);
  

•   spin_unlock_irqrestore(&id_map->lock, flags);
  

•   raw_spin_unlock_irqrestore(&id_map->lock, flags);
  
    DUMP_ID(id);
    DUMP_ID_MAP(id_map);
  

@@ -207,9 +207,9 @@ static void coresight_trace_id_map_put_system_id(struct coresight_trace_id_map * { unsigned long flags;

•   spin_lock_irqsave(&id_map->lock, flags);
  

•   raw_spin_lock_irqsave(&id_map->lock, flags);
    coresight_trace_id_free(id, id_map);
  

•   spin_unlock_irqrestore(&id_map->lock, flags);
  

•   raw_spin_unlock_irqrestore(&id_map->lock, flags);
  
    DUMP_ID(id);
    DUMP_ID_MAP(id_map);
  

diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 924b58c343b3..6446ca1f09d8 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -233,7 +233,7 @@ struct coresight_trace_id_map { DECLARE_BITMAP(used_ids, CORESIGHT_TRACE_IDS_MAX); atomic_t __percpu *cpu_map; atomic_t perf_cs_etm_session_active;

•   spinlock_t lock;
  

•   raw_spinlock_t lock;
  

};

/**

LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}

Reviewed-by: Mike Leach mike.leach@linaro.org

-- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK