Re: [PATCH v5 14/14] coresight: trace-id: Add debug & test macros to Trace ID allocation

On 01/11/2022 16:31, Mike Leach wrote:

Adds in a number of pr_debug macros to allow the debugging and test of the trace ID allocation system.

Signed-off-by: Mike Leach mike.leach@linaro.org

.../hwtracing/coresight/coresight-trace-id.c | 33 +++++++++++++++++++ 1 file changed, 33 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-trace-id.c b/drivers/hwtracing/coresight/coresight-trace-id.c index 8e05a244c9d6..1588bad60715 100644 --- a/drivers/hwtracing/coresight/coresight-trace-id.c +++ b/drivers/hwtracing/coresight/coresight-trace-id.c @@ -64,6 +64,27 @@ static void coresight_trace_id_set_pend_rel(int id, struct coresight_trace_id_ma set_bit(id, id_map->pend_rel_ids); } +/* #define TRACE_ID_DEBUG 1 */ +#ifdef TRACE_ID_DEBUG

+static void coresight_trace_id_dump_table(struct coresight_trace_id_map *id_map,

• 			  const char *func_name)
  

+{

• pr_debug("%s id_map::\n", func_name);
• pr_debug("Avial= %*pb\n", CORESIGHT_TRACE_IDS_MAX, id_map->used_ids);

minor nit: "Avail". Rather, shouldn't it be "Used" ?

Otherwise, the code looks good to me. The only concern is, the code could be stale without actually getting compiled. Could we turn this to may be:

#if defined(TRACE_ID_DEBUG) || defined(CONFIG_COMPILE_TEST)

or even tie this to a CONFIG, so that the code can be tested.

e.g., CONFIG_CORESIGHT_DEBUG_TRACEID depending on the DEBUG_KERNEL

Suzuki

• pr_debug("Pend = %*pb\n", CORESIGHT_TRACE_IDS_MAX, id_map->pend_rel_ids);

+} +#define DUMP_ID_MAP(map) coresight_trace_id_dump_table(map, __func__) +#define DUMP_ID_CPU(cpu, id) pr_debug("%s called; cpu=%d, id=%d\n", __func__, cpu, id) +#define DUMP_ID(id) pr_debug("%s called; id=%d\n", __func__, id) +#define PERF_SESSION(n) pr_debug("%s perf count %d\n", __func__, n) +#else +#define DUMP_ID_MAP(map) +#define DUMP_ID(id) +#define DUMP_ID_CPU(cpu, id) +#define PERF_SESSION(n) +#endif

• /* release all pending IDs for all current maps & clear CPU associations */ static void coresight_trace_id_release_all_pending(void) {

@@ -81,6 +102,7 @@ static void coresight_trace_id_release_all_pending(void) clear_bit(cpu, cpu_id_release_pending); } spin_unlock_irqrestore(&id_map_lock, flags);

• DUMP_ID_MAP(id_map); }

static int coresight_trace_id_map_get_cpu_id(int cpu, struct coresight_trace_id_map *id_map) @@ -120,6 +142,8 @@ static int coresight_trace_id_map_get_cpu_id(int cpu, struct coresight_trace_id_ get_cpu_id_out_unlock: spin_unlock_irqrestore(&id_map_lock, flags);

• DUMP_ID_CPU(cpu, id);
• DUMP_ID_MAP(id_map); return id; }

@@ -146,6 +170,8 @@ static void coresight_trace_id_map_put_cpu_id(int cpu, struct coresight_trace_id } spin_unlock_irqrestore(&id_map_lock, flags);

• DUMP_ID_CPU(cpu, id);
• DUMP_ID_MAP(id_map); }

static int coresight_trace_id_map_get_system_id(struct coresight_trace_id_map *id_map) @@ -157,6 +183,8 @@ static int coresight_trace_id_map_get_system_id(struct coresight_trace_id_map *i id = coresight_trace_id_alloc_new_id(id_map, 0); spin_unlock_irqrestore(&id_map_lock, flags);

• DUMP_ID(id);
• DUMP_ID_MAP(id_map); return id; }

@@ -167,6 +195,9 @@ static void coresight_trace_id_map_put_system_id(struct coresight_trace_id_map * spin_lock_irqsave(&id_map_lock, flags); coresight_trace_id_free(id, id_map); spin_unlock_irqrestore(&id_map_lock, flags);

• DUMP_ID(id);
• DUMP_ID_MAP(id_map); }

/* API functions */ @@ -204,6 +235,7 @@ EXPORT_SYMBOL_GPL(coresight_trace_id_put_system_id); void coresight_trace_id_perf_start(void) { atomic_inc(&perf_cs_etm_session_active);

• PERF_SESSION(atomic_read(&perf_cs_etm_session_active)); } EXPORT_SYMBOL_GPL(coresight_trace_id_perf_start);

@@ -211,6 +243,7 @@ void coresight_trace_id_perf_stop(void) { if (!atomic_dec_return(&perf_cs_etm_session_active)) coresight_trace_id_release_all_pending();

• PERF_SESSION(atomic_read(&perf_cs_etm_session_active)); } EXPORT_SYMBOL_GPL(coresight_trace_id_perf_stop);