same_state_synchronize_srcu(9)

💅 same_state_synchronize_srcu(9) — the Kernel API Manual, bestie edition ✨

okay so welcome to same_state_synchronize_srcu(9), a genuinely tiny little function in the Linux kernel API manual and honestly? she's iconic in her simplicity. this is her moment, let's get into it 🎀

---

🌸 NAME 🌸

same_state_synchronize_srcu — literally just: are two old-state values identical? that's the whole vibe check 💖

---

✨ SYNOPSIS ✨

bool same_state_synchronize_srcu (unsigned long oldstate1 , unsigned
long oldstate2 );

she takes two unsigned longs and hands you back a bool. no cap, that's it 🫶

---

🦋 ARGUMENTS 🦋

• oldstate1 — the first old-state value, bestie. first out of two 🌸
• oldstate2 — and this one's the second old-state value 💜

---

🔥 DESCRIPTION 🔥

so here's the tea ☕ — these two old-state values must have been obtained from one of these three:

• get_state_synchronize_srcu
• start_poll_synchronize_srcu
• get_completed_synchronize_srcu

like, that's a hard requirement, not a suggestion, iykyk 🙈

she returns true if the two values are identical and false otherwise. periodt. 💅

and why do we care?? because this lets structures whose lifetimes are tracked by old-state values push those values to a list header — which means those structures can be slightly smaller. tiny struct, big slay 👑 lowkey a main character optimization fr fr.

---

👀 SEE ALSO 👀

Kernel file ./include/linux/srcu.h — go read it, she's right there 🧚

• get_completed_synchronize_srcu(9)
• srcu_read_lock_held(9)
• srcu_dereference_check(9)
• srcu_dereference(9)
• srcu_dereference_notrace(9)
• srcu_read_lock(9)
• srcu_read_lock_fast(9)
• srcu_read_lock_fast_updown(9)
• srcu_down_read_fast(9)
• srcu_read_lock_nmisafe(9)
• srcu_down_read(9)
• srcu_read_unlock(9)
• srcu_read_unlock_fast(9)
• srcu_read_unlock_fast_updown(9)
• srcu_up_read_fast(9)
• srcu_read_unlock_nmisafe(9)
• srcu_up_read(9)
• smp_mb__after_srcu_read_unlock(9)
• smp_mb__after_srcu_read_lock(9)

like, that's the whole srcu friend group right there — go say hi to all of them 💖✨

---

and that's the page, bestie!! 🎀 this whole thing lives in <bold>./include/linux</bold> and it's dated October 2026 — so yeah, timestamped straight from the source, no cap. mwah, go read some kernel headers 💋🌈⭐