Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
srcu: Add srcu_read_lock_fast_notrace() and srcu_read_unlock_fast_notrace()
This commit adds no-trace variants of the srcu_read_lock_fast() and
srcu_read_unlock_fast() functions for tracing use.
[ paulmck: Apply notrace feedback from Joel Fernandes, Steven Rostedt, and Mathieu Desnoyers. ]
[ paulmck: Apply excess-notrace feedback from Boqun Feng. ]
Link: https://lore.kernel.org/all/20250721162433.10454-1-paulmck@kernel.org
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: <bpf@vger.kernel.org>
+28
-2
+25
include/linux/srcu.h
+25
include/linux/srcu.h
···
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return retval;
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}
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+
/*
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* Used by tracing, cannot be traced and cannot call lockdep.
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* See srcu_read_lock_fast() for more information.
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*/
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static inline struct srcu_ctr __percpu *srcu_read_lock_fast_notrace(struct srcu_struct *ssp)
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__acquires(ssp)
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{
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struct srcu_ctr __percpu *retval;
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+
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srcu_check_read_flavor_force(ssp, SRCU_READ_FLAVOR_FAST);
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retval = __srcu_read_lock_fast(ssp);
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return retval;
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}
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+
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/**
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* srcu_down_read_fast - register a new reader for an SRCU-protected structure.
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* @ssp: srcu_struct in which to register the new reader.
···
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srcu_lock_release(&ssp->dep_map);
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__srcu_read_unlock_fast(ssp, scp);
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RCU_LOCKDEP_WARN(!rcu_is_watching(), "RCU must be watching srcu_read_unlock_fast().");
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}
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+
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/*
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* Used by tracing, cannot be traced and cannot call lockdep.
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* See srcu_read_unlock_fast() for more information.
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*/
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static inline void srcu_read_unlock_fast_notrace(struct srcu_struct *ssp,
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struct srcu_ctr __percpu *scp) __releases(ssp)
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{
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srcu_check_read_flavor(ssp, SRCU_READ_FLAVOR_FAST);
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__srcu_read_unlock_fast(ssp, scp);
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}
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/**
+3
-2
include/linux/srcutree.h
+3
-2
include/linux/srcutree.h
···
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* on architectures that support NMIs but do not supply NMI-safe
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* implementations of this_cpu_inc().
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*/
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-
static inline struct srcu_ctr __percpu *__srcu_read_lock_fast(struct srcu_struct *ssp)
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static inline struct srcu_ctr __percpu notrace *__srcu_read_lock_fast(struct srcu_struct *ssp)
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{
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struct srcu_ctr __percpu *scp = READ_ONCE(ssp->srcu_ctrp);
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···
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* on architectures that support NMIs but do not supply NMI-safe
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* implementations of this_cpu_inc().
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*/
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-
static inline void __srcu_read_unlock_fast(struct srcu_struct *ssp, struct srcu_ctr __percpu *scp)
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static inline void notrace
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__srcu_read_unlock_fast(struct srcu_struct *ssp, struct srcu_ctr __percpu *scp)
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{
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barrier(); /* Avoid leaking the critical section. */
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if (!IS_ENABLED(CONFIG_NEED_SRCU_NMI_SAFE))