The rcu_dereference_raw_notrace() API name is confusing. It is equivalent to rcu_dereference_raw() except that it also does sparse pointer checking. There are only a few users of rcu_dereference_raw_notrace(). This patches renames all of them to be rcu_dereference_raw_check with the "check" indicating sparse checking. Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> --- Previous discussion is here: https://lore.kernel.org/linuxppc-dev/20190528200014.GV28207@xxxxxxxxxxxxx/T/ Documentation/RCU/Design/Requirements/Requirements.html | 2 +- arch/powerpc/include/asm/kvm_book3s_64.h | 2 +- include/linux/rculist.h | 4 ++-- include/linux/rcupdate.h | 2 +- kernel/trace/ftrace_internal.h | 8 ++++---- kernel/trace/trace.c | 4 ++-- 6 files changed, 11 insertions(+), 11 deletions(-) diff --git a/Documentation/RCU/Design/Requirements/Requirements.html b/Documentation/RCU/Design/Requirements/Requirements.html index f04c467e55c5..467251f7fef6 100644 --- a/Documentation/RCU/Design/Requirements/Requirements.html +++ b/Documentation/RCU/Design/Requirements/Requirements.html @@ -2514,7 +2514,7 @@ disabled across the entire RCU read-side critical section. <p> It is possible to use tracing on RCU code, but tracing itself uses RCU. -For this reason, <tt>rcu_dereference_raw_notrace()</tt> +For this reason, <tt>rcu_dereference_raw_check()</tt> is provided for use by tracing, which avoids the destructive recursion that could otherwise ensue. This API is also used by virtualization in some architectures, diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h index 21b1ed5df888..53388a311967 100644 --- a/arch/powerpc/include/asm/kvm_book3s_64.h +++ b/arch/powerpc/include/asm/kvm_book3s_64.h @@ -546,7 +546,7 @@ static inline void note_hpte_modification(struct kvm *kvm, */ static inline struct kvm_memslots *kvm_memslots_raw(struct kvm *kvm) { - return rcu_dereference_raw_notrace(kvm->memslots[0]); + return rcu_dereference_raw_check(kvm->memslots[0]); } extern void kvmppc_mmu_debugfs_init(struct kvm *kvm); diff --git a/include/linux/rculist.h b/include/linux/rculist.h index e91ec9ddcd30..10aab1d2d471 100644 --- a/include/linux/rculist.h +++ b/include/linux/rculist.h @@ -642,10 +642,10 @@ static inline void hlist_add_behind_rcu(struct hlist_node *n, * not do any RCU debugging or tracing. */ #define hlist_for_each_entry_rcu_notrace(pos, head, member) \ - for (pos = hlist_entry_safe (rcu_dereference_raw_notrace(hlist_first_rcu(head)),\ + for (pos = hlist_entry_safe (rcu_dereference_raw_check(hlist_first_rcu(head)),\ typeof(*(pos)), member); \ pos; \ - pos = hlist_entry_safe(rcu_dereference_raw_notrace(hlist_next_rcu(\ + pos = hlist_entry_safe(rcu_dereference_raw_check(hlist_next_rcu(\ &(pos)->member)), typeof(*(pos)), member)) /** diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 0c9b92799abc..e5161e377ad4 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -478,7 +478,7 @@ do { \ * The no-tracing version of rcu_dereference_raw() must not call * rcu_read_lock_held(). */ -#define rcu_dereference_raw_notrace(p) __rcu_dereference_check((p), 1, __rcu) +#define rcu_dereference_raw_check(p) __rcu_dereference_check((p), 1, __rcu) /** * rcu_dereference_protected() - fetch RCU pointer when updates prevented diff --git a/kernel/trace/ftrace_internal.h b/kernel/trace/ftrace_internal.h index 0515a2096f90..0456e0a3dab1 100644 --- a/kernel/trace/ftrace_internal.h +++ b/kernel/trace/ftrace_internal.h @@ -6,22 +6,22 @@ /* * Traverse the ftrace_global_list, invoking all entries. The reason that we - * can use rcu_dereference_raw_notrace() is that elements removed from this list + * can use rcu_dereference_raw_check() is that elements removed from this list * are simply leaked, so there is no need to interact with a grace-period - * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle + * mechanism. The rcu_dereference_raw_check() calls are needed to handle * concurrent insertions into the ftrace_global_list. * * Silly Alpha and silly pointer-speculation compiler optimizations! */ #define do_for_each_ftrace_op(op, list) \ - op = rcu_dereference_raw_notrace(list); \ + op = rcu_dereference_raw_check(list); \ do /* * Optimized for just a single item in the list (as that is the normal case). */ #define while_for_each_ftrace_op(op) \ - while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \ + while (likely(op = rcu_dereference_raw_check((op)->next)) && \ unlikely((op) != &ftrace_list_end)) extern struct ftrace_ops __rcu *ftrace_ops_list; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 2c92b3d9ea30..1d69110d9e5b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2642,10 +2642,10 @@ static void ftrace_exports(struct ring_buffer_event *event) preempt_disable_notrace(); - export = rcu_dereference_raw_notrace(ftrace_exports_list); + export = rcu_dereference_raw_check(ftrace_exports_list); while (export) { trace_process_export(export, event); - export = rcu_dereference_raw_notrace(export->next); + export = rcu_dereference_raw_check(export->next); } preempt_enable_notrace(); -- 2.22.0.410.gd8fdbe21b5-goog
