list_for_each_entry_srcu(9)

💅 list_for_each_entry_srcu — a lil intro

okay so first things first, bestie: this page lives in the Kernel API Manual ✨ (yes, that kernel, and yes, we're being cute about it). Buckle up, because this one is a loop macro and it's genuinely iconic 🎀

✨ NAME ✨

list_for_each_entry_srcu — iterate over rcu list of given type 🦋

🌸 SYNOPSIS 🌸

list_for_each_entry_srcu (pos , head , member , cond );

🎀 ARGUMENTS 🎀

• pos — the type * to use as a loop cursor. this is your main character pointer, she walks the list for you 💅
• head — the head for your list. the origin, the queen bee 👑
• member — the name of the list_head within the struct. iykyk, it's the lil field that makes the struct listable 🧚
• cond — lockdep expression for the lock required to traverse the list. this is the vibe check for your locking, fr fr 🔒

💖 DESCRIPTION 💖

so here's the tea 🍓: this list-traversal primitive may safely run concurrently with the _rcu list-mutation primitives such as list_add_rcu as long as the traversal is guarded by srcu_read_lock. literally that's the whole deal — no cap.

and the lockdep expression srcu_read_lock_held can be passed as the cond argument from the read side. so you get the safety check and the traversal, cute and correct at the same time 😭✨

bestie pls note: the "may safely run concurrently" part is conditional on that srcu_read_lock guard — don't skip it, that's not a vibe, that's a bug 💀

🦋 SEE ALSO 🦋

Kernel file ./include/linux/rculist.h — and honestly the whole rcu family showed up to the group chat 🌈:

• list_for_each_rcu(9)
• list_tail_rcu(9)
• list_add_rcu(9)
• list_add_tail_rcu(9)
• list_del_rcu(9)
• list_bidir_del_rcu(9)
• hlist_del_init_rcu(9)
• list_replace_rcu(9)
• list_splice_rcu(9)
• __list_splice_init_rcu(9)
• list_splice_init_rcu(9)
• list_splice_tail_init_rcu(9)
• list_entry_rcu(9)
• list_first_or_null_rcu(9)
• list_next_or_null_rcu(9)
• list_for_each_entry_rcu(9)
• list_entry_lockless(9)
• list_for_each_entry_lockless(9)
• list_for_each_entry_continue_rcu(9)
• list_for_each_entry_from_rcu(9)
• hlist_del_rcu(9)
• hlist_replace_rcu(9)
• hlists_swap_heads_rcu(9)
• hlist_add_head_rcu(9)
• hlist_add_tail_rcu(9)
• hlist_add_before_rcu(9)
• hlist_add_behind_rcu(9)
• hlist_for_each_entry_rcu(9)
• hlist_for_each_entry_srcu(9)
• hlist_for_each_entry_rcu_notrace(9)
• hlist_for_each_entry_rcu_bh(9)
• hlist_for_each_entry_continue_rcu(9)
• hlist_for_each_entry_continue_rcu_bh(9)
• hlist_for_each_entry_from_rcu(9)

okay that's the whole page, you ate that 🫶 signing off from ./include/linux, dated October 2026, page list_for_each_entry_srcu(9) — slay, go guard your traversal, mwah 💋💅