pwq_dec_nr_active(9)

📦 version 7.3.1, in nixpkgs unstable

💅 pwq_dec_nr_active — a Kernel API Manual moment (section 9, bestie)

Okay so this is a page from the Kernel API Manual, and honestly it's one of those tiny little functions that does a huge amount of emotional (and scheduler) labor 🫶. Let's get into it.

🌸 NAME 🌸

pwq_dec_nr_active — retire an active count ✨

Like, it takes one (1) active count out of the group chat and quietly retires it. No drama, just bookkeeping 💅.

🦋 SYNOPSIS 🦋

void pwq_dec_nr_active (struct pool_workqueue *pwq );

Returns void, so no surprises, no callback chaos, we love a low-stakes queen 👑.

🎀 ARGUMENTS 🎀

  • pwq — the pool_workqueue of interest. That's the one you're looking at. The main character, if you will 👀.

💖 DESCRIPTION 💖

So here's the vibe: this function decrements pwq's nr_active — yes, the count goes down by one, icon behavior — and then it tries to activate the first inactive work item 🔥. Like, a slot just freed up, so it goes and taps the next work item on the shoulder and is like "you're up, bestie."

And here's the spicy part 🌶️: for unbound workqueues, this function may temporarily drop pwq->pool->lock. So the lock is not held for the whole ride — it lets go for a sec, which is exactly the kind of thing you want to know before you go assuming anything about locking around here, ngl 😭. That's a real caveat, so don't sleep on it.

⭐ SEE ALSO ⭐

Go read the source, and then go read all of these, because the cross-reference game here is genuinely unmatched — it's giving "linked list of knowledge" 🌈. The kernel file is ./kernel/workqueue.c, and the gang is:

Like, that's the whole workqueue cinematic universe in one SEE ALSO, and every single one of them is a real page — go click through them, iykyk 💜

🧚 sign-off 🧚

This lil beauty lives in ./kernel (yes, the source tree, mwah 💋), it's the October 2026 vintage, and its whole name-tag says pwq_dec_nr_active(9). Go forth, decrement responsibly, and remember: the lock might briefly dip out on unbound workqueues 💀✨ periodt.

📦 where this page comes from