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| author | Hauke Mehrtens <hauke@hauke-m.de> | 2020-03-12 11:18:40 +0100 |
|---|---|---|
| committer | Hauke Mehrtens <hauke@hauke-m.de> | 2020-03-19 19:40:43 +0100 |
| commit | b0656050457ef9ee8bebb40c3f826e77cd209a06 (patch) | |
| tree | fd480cd85b47beb2cbd5f8ed6363ecfa8f55da2e | |
| parent | d97302fd5b16a90bca09682df8696895fedf06b1 (diff) | |
| download | backports-b0656050457ef9ee8bebb40c3f826e77cd209a06.tar.gz | |
backports: rcupdate.h: Add rcu_swap_protected()
Backport rcu_swap_protected() from upstream Linux commit 26e3e3cb0560
("scsi: rcu: Introduce rcu_swap_protected()"). This is used by the mt76
driver.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
| -rw-r--r-- | backport/backport-include/linux/rcupdate.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/backport/backport-include/linux/rcupdate.h b/backport/backport-include/linux/rcupdate.h index cec4b3e8..db501007 100644 --- a/backport/backport-include/linux/rcupdate.h +++ b/backport/backport-include/linux/rcupdate.h @@ -59,4 +59,22 @@ rcu_head_after_call_rcu(struct rcu_head *rhp, rcu_callback_t f) } #endif /* < 4.20 */ +#ifndef rcu_swap_protected +/** + * rcu_swap_protected() - swap an RCU and a regular pointer + * @rcu_ptr: RCU pointer + * @ptr: regular pointer + * @c: the conditions under which the dereference will take place + * + * Perform swap(@rcu_ptr, @ptr) where @rcu_ptr is an RCU-annotated pointer and + * @c is the argument that is passed to the rcu_dereference_protected() call + * used to read that pointer. + */ +#define rcu_swap_protected(rcu_ptr, ptr, c) do { \ + typeof(ptr) __tmp = rcu_dereference_protected((rcu_ptr), (c)); \ + rcu_assign_pointer((rcu_ptr), (ptr)); \ + (ptr) = __tmp; \ +} while (0) +#endif + #endif /* __BACKPORT_LINUX_RCUPDATE_H */ |