Re: [PATCH] treewide: Rename rcu_dereference_raw_notrace to _check
On Fri, Jul 12, 2019 at 08:01:07AM -0700, Paul E. McKenney wrote:
> On Thu, Jul 11, 2019 at 04:45:41PM -0400, Joel Fernandes (Google) wrote:
> > 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)
>
> I queued this, but reworked the commit log and fixed a couple of
> irritating checkpatch issues that were in the original code.
> Does this work for you?
Thanks, yes it looks good to me.
thanks,
- Joel
>
> Thanx, Paul
>
>
>
> commit bd5c0fea6016c90cf7a9eb0435cd0c373dfdac2f
> Author: Joel Fernandes (Google)
> Date: Thu Jul 11 16:45:41 2019 -0400
>
> treewide: Rename rcu_dereference_raw_notrace() to _check()
>
> 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)
> [ paulmck: Fix checkpatch warnings about parentheses. ]
> Signed-off-by: Paul E. McKenney
>
> 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.
>
> It is possible to use tracing on RCU code, but tracing itself
> uses RCU.
> -For this reason, rcu_dereference_raw_notrace()
> +For this reason, rcu_dereference_raw_check()
> 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..932296144131 100644
> --- a/include/linux/rculist.h
> +++ b/include/linux/rculist.h
> @@ -622,7 +622,7 @@ static inline void hlist_add_behind_rcu(struct hlist_node
> *n,
> * as long as the traversal is guarded by rcu_read_lock().
> */
> #define hlist_for_each_entry_rcu(pos, head, member) \
> - for (pos = hlist_entry_safe
> (rcu_dereference_raw(hlist_first_rcu(head)),\
> + for (pos = hlist_entry_safe(rcu_dereference_raw(hlist_first_rcu(head)),\
> typeof(*(pos)), member);\
> pos;\
> pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(\
> @@ -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)
Re: [PATCH] treewide: Rename rcu_dereference_raw_notrace to _check
On Thu, Jul 11, 2019 at 04:45:41PM -0400, Joel Fernandes (Google) wrote:
> 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)
I queued this, but reworked the commit log and fixed a couple of
irritating checkpatch issues that were in the original code.
Does this work for you?
Thanx, Paul
commit bd5c0fea6016c90cf7a9eb0435cd0c373dfdac2f
Author: Joel Fernandes (Google)
Date: Thu Jul 11 16:45:41 2019 -0400
treewide: Rename rcu_dereference_raw_notrace() to _check()
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)
[ paulmck: Fix checkpatch warnings about parentheses. ]
Signed-off-by: Paul E. McKenney
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.
It is possible to use tracing on RCU code, but tracing itself
uses RCU.
-For this reason, rcu_dereference_raw_notrace()
+For this reason, rcu_dereference_raw_check()
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..932296144131 100644
--- a/include/linux/rculist.h
+++ b/include/linux/rculist.h
@@ -622,7 +622,7 @@ static inline void hlist_add_behind_rcu(struct hlist_node
*n,
* as long as the traversal is guarded by rcu_read_lock().
*/
#define hlist_for_each_entry_rcu(pos, head, member)\
- for (pos = hlist_entry_safe
(rcu_dereference_raw(hlist_first_rcu(head)),\
+ for (pos = hlist_entry_safe(rcu_dereference_raw(hlist_first_rcu(head)),\
typeof(*(pos)), member);\
pos;\
pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(\
@@ -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
---
Re: [PATCH] treewide: Rename rcu_dereference_raw_notrace to _check
On Thu, Jul 11, 2019 at 4:45 PM Joel Fernandes (Google) wrote: > > 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) There also these _notrace things but I am Ok with leaving them alone for now: hash_for_each_possible_rcu_notrace hlist_for_each_entry_rcu_notrace - Joel
[PATCH] treewide: Rename rcu_dereference_raw_notrace to _check
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)
---
Previous discussion is here:
https://lore.kernel.org/linuxppc-dev/20190528200014.gv28...@linux.ibm.com/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.
It is possible to use tracing on RCU code, but tracing itself
uses RCU.
-For this reason, rcu_dereference_raw_notrace()
+For this reason, rcu_dereference_raw_check()
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 =
