rcu_read_lock_bh_held(9)

rcu_read_lock_bh_held9

Might we be in rcu-bh read-side critical section?

Usage

int rcu_read_lock_bh_held(void);

Arguments

void

no arguments

Overview

Check for bottom half being disabled, which covers both the CONFIG_PROVE_RCU and not cases. Note that if someone uses rcu_read_lock_bh, but then later enables BH, lockdep (if enabled) will show the situation. This is useful for debug checks in functions that require that they be called within an RCU read-side critical section.

Check debug_lockdep_rcu_enabled to prevent false positives during boot.

Note that rcu_read_lock is disallowed if the CPU is either idle or offline from an RCU perspective, so check for those as well.

Releases

2 releases since Debian 7 (Wheezy); the text changed 1 time.

  1. 7
  2. 8

From linux-manual-3.16 3.16.56-1+deb8u1 in Debian 8 (Jessie). Parsed by carta from the page's man source.