11:02 <baotiao> where can I see the conversations log?

12:27 <gromero> Hi. I'm using systemtap to tap a function which contains a printk("HELLO"); I can see it was hit (since I see "HELLO" in dmesg) but systemtap shows nothing. Looks like that sometimes it's able to catch the function call but in some cases it just miss the call. Is that any known issue?

12:37 <baotiao> no can you show me you probe

13:16 <fche> gromero, the kernel can sometimes cause a kprobe not to fire; we usually get told of this with a 'missed probe' counter at termination

13:16 <fche> but that's relatively unlikely

13:17 <gromero> fche: hum, right. My probe is: https://github.com/leitao/htm_torture/blob/31533dfd9f2419b757f19b233f51adaf652f2c80/systemtap/tapset/tap8.d

13:17 <gromero> fche: in function "load_up_fpu"

13:21 <gromero> fche: when you say "missed probe" counter at termination, what termination you are talk about? when I hit Ctrl-C? I just see nothing: like: https://hastebin.com/raw/hicawucisi

13:22 <gromero> fche: but sometimes it works: https://hastebin.com/raw/bozocezace

13:22 <gromero> that's indeed weird...

13:54 <fche> gromero, try running with stap -t ....

13:54 <gromero> fche: ok

13:57 <gromero> fche: looks like didn't change much. I'll double check if the condition to hit load_up_fpu is indeed satisfied. ta!

14:15 <gromero> fche: probe was not missed, indeed the condition I was looking for is dependent of a condition not always satisfied (the condition is time dependent, it has a counter that overflows from time to time)...

14:16 <gromero> so all is fine with systemtap

14:16 <fche> good stuff!

14:29 <gromero> fche: heh yep :)

14:29 <fche> by the way, on newer stap, you may not need to be so repetitious with the current_task()->foo->bar constructs all the time

14:29 <fche> you may be able to store foo = current_task()->foo and then use foo->bar elsewhere in the script

14:30 <fche> or that sort of thing

14:30 <fche> or use macros

14:30 <fche> but anyway this works too

14:31 <gromero> fche: got it! thanks for the hint :)