diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 38 |
1 files changed, 23 insertions, 15 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 70202e60a60a..d3e630dd36f8 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5453,10 +5453,31 @@ int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) return 0; } -int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) +static int trace_alloc_tgid_map(void) { int *map; + if (tgid_map) + return 0; + + tgid_map_max = pid_max; + map = kvcalloc(tgid_map_max + 1, sizeof(*tgid_map), + GFP_KERNEL); + if (!map) + return -ENOMEM; + + /* + * Pairs with smp_load_acquire() in + * trace_find_tgid_ptr() to ensure that if it observes + * the tgid_map we just allocated then it also observes + * the corresponding tgid_map_max value. + */ + smp_store_release(&tgid_map, map); + return 0; +} + +int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) +{ if ((mask == TRACE_ITER_RECORD_TGID) || (mask == TRACE_ITER_RECORD_CMD)) lockdep_assert_held(&event_mutex); @@ -5479,20 +5500,7 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) trace_event_enable_cmd_record(enabled); if (mask == TRACE_ITER_RECORD_TGID) { - if (!tgid_map) { - tgid_map_max = pid_max; - map = kvcalloc(tgid_map_max + 1, sizeof(*tgid_map), - GFP_KERNEL); - - /* - * Pairs with smp_load_acquire() in - * trace_find_tgid_ptr() to ensure that if it observes - * the tgid_map we just allocated then it also observes - * the corresponding tgid_map_max value. - */ - smp_store_release(&tgid_map, map); - } - if (!tgid_map) { + if (trace_alloc_tgid_map() < 0) { tr->trace_flags &= ~TRACE_ITER_RECORD_TGID; return -ENOMEM; } |