On Mon, Aug 03, 2020 at 11:32:39AM -0400, Steven Rostedt wrote: > On Mon, 3 Aug 2020 14:47:19 +0000 > Kalesh Singh <kaleshsingh@xxxxxxxxxx> wrote: > > > +DECLARE_EVENT_CLASS(dma_buf_ref_template, > > + > > + TP_PROTO(struct task_struct *task, struct file *filp), > > + > > + TP_ARGS(task, filp), > > + > > + TP_STRUCT__entry( > > + __field(u32, tgid) > > + __field(u32, pid) > > I only see "current" passed in as "task". Why are you recording the pid > and tgid as these are available by the tracing infrastructure. > > At least the pid is saved at every event. You can see the tgid when > enabling the "record_tgid". > > # trace-cmd start -e all -O record_tgid > # trace-cmd show > > # tracer: nop > # > # entries-in-buffer/entries-written: 39750/39750 #P:8 > # > # _-----=> irqs-off > # / _----=> need-resched > # | / _---=> hardirq/softirq > # || / _--=> preempt-depth > # ||| / delay > # TASK-PID TGID CPU# |||| TIMESTAMP FUNCTION > # | | | | |||| | | > trace-cmd-28284 (28284) [005] .... 240338.934671: sys_exit: NR 1 = 1 > kworker/3:2-27891 (27891) [003] d... 240338.934671: timer_start: timer=00000000d643debd function=delayed_work_timer_fn expires=4535008893 [timeout=1981] cpu=3 idx=186 flags=I > trace-cmd-28284 (28284) [005] .... 240338.934672: sys_write -> 0x1 > kworker/3:2-27891 (27891) [003] .... 240338.934672: workqueue_execute_end: work struct 000000008fddd403: function psi_avgs_work > kworker/3:2-27891 (27891) [003] .... 240338.934673: workqueue_execute_start: work struct 00000000111c941e: function dbs_work_handler > kworker/3:2-27891 (27891) [003] .... 240338.934673: workqueue_execute_end: work struct 00000000111c941e: function dbs_work_handler > kworker/3:2-27891 (27891) [003] d... 240338.934673: rcu_utilization: Start context switch > kworker/3:2-27891 (27891) [003] d... 240338.934673: rcu_utilization: End context switch > > -- Steve > Thanks for the comments Steve. I'll remove the task arg. > > + __field(u64, size) > > + __field(s64, count) > > + __string(exp_name, dma_buffer(filp)->exp_name) > > + __string(name, dma_buffer(filp)->name ? dma_buffer(filp)->name : UNKNOWN) > > + __field(u64, i_ino) > > + ), > > + > > + TP_fast_assign( > > + __entry->tgid = task->tgid; > > + __entry->pid = task->pid; > > + __entry->size = dma_buffer(filp)->size; > > + __entry->count = file_count(filp); > > + __assign_str(exp_name, dma_buffer(filp)->exp_name); > > + __assign_str(name, dma_buffer(filp)->name ? dma_buffer(filp)->name : UNKNOWN); > > + __entry->i_ino = filp->f_inode->i_ino; > > + ), > > +
