diff mbox series

[v7,net-next,06/18] net: introduce rcu_replace_pointer_rtnl

Message ID 20231016093549.181952-7-jhs@mojatatu.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series Introducing P4TC | expand

Checks

Context Check Description
netdev/series_format fail Series longer than 15 patches (and no cover letter)
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 4794 this patch: 4794
netdev/cc_maintainers warning 3 maintainers not CCed: gnault@redhat.com liuhangbin@gmail.com martin@strongswan.org
netdev/build_clang success Errors and warnings before: 1626 this patch: 1626
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 5066 this patch: 5066
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 18 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jamal Hadi Salim Oct. 16, 2023, 9:35 a.m. UTC 
We use rcu_replace_pointer(rcu_ptr, ptr, lockdep_rtnl_is_held()) throughout
the P4TC infrastructure code.

It may be useful for other use cases, so we create a helper.

Co-developed-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Co-developed-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
---
 include/linux/rtnetlink.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)
diff mbox series

Patch

diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index 3d6cf306c..971055e66 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -62,6 +62,18 @@  static inline bool lockdep_rtnl_is_held(void)
 #define rcu_dereference_rtnl(p)					\
 	rcu_dereference_check(p, lockdep_rtnl_is_held())
 
+/**
+ * rcu_replace_pointer_rtnl - replace an RCU pointer under rtnl_lock, returning
+ * its old value
+ * @rcu_ptr: RCU pointer, whose old value is returned
+ * @ptr: regular pointer
+ *
+ * Perform a replacement under rtnl_lock, where @rcu_ptr is an RCU-annotated
+ * pointer. The old value of @rcu_ptr is returned, and @rcu_ptr is set to @ptr
+ */
+#define rcu_replace_pointer_rtnl(rcu_ptr, ptr)			\
+	rcu_replace_pointer(rcu_ptr, ptr, lockdep_rtnl_is_held())
+
 /**
  * rtnl_dereference - fetch RCU pointer when updates are prevented by RTNL
  * @p: The pointer to read, prior to dereferencing