thread_group_sample_cputime(9)

💅 thread_group_sample_cputime ✨

ok so bestie, welcome to the Kernel API Manual entry for thread_group_sample_cputime — yes that's a mouthful, yes it's iconic, and yes we're gonna get through it together 🫶

---

🌸 NAME 🌸

thread_group_sample_cputime — sample cputime for a given task ⏱️✨

---

🎀 SYNOPSIS 🎀

void thread_group_sample_cputime (struct task_struct *tsk , u64 *samples );

literally that's the whole signature. no cap. 💅

---

🦋 ARGUMENTS 🦋

• tsk — the task whose cputime needs to be started 👑
• samples — your storage spot for the time samples, aka where the numbers go 🍓

---

🔥 DESCRIPTION 🔥

okay so here's the vibe: this one gets called from sys_getitimer to calculate the expiry time of an active timer. which means — and this is the important part, bestie — group cputime accounting is already active. it also gets called with the task sighand lock held, so don't go doing anything weird in there, iykyk 🔒

what does it actually do? it updates the times with an up-to-date sample of the thread group cputimes. that's it. that's the whole job. main character energy, minimal drama ✨

---

🌈 SEE ALSO 🌈

• Kernel file ./kernel/time/posix-cpu-timers.c 📁
• thread_group_start_cputime(9)
• task_cputimers_expired(9)
• fastpath_timer_check(9)

go read those too, fr fr, they're all besties 💖

---

ngl if you skimmed all of that, the takeaway is: it samples cputime for a task's thread group, it's called from sys_getitimer with the sighand lock held, and group cputime accounting is already active when you get here. periodt 💅

---

and that's the page!! 🧚 this little gem lives under ./kernel/time and it's dated October 2026 — mwah, sending you off with a kiss and a 🎀, go forth and sample those cputimes bestie 💜