Commit ce4dce12 authored May 25, 2020 by Uladzislau Rezki (Sony) Committed by Paul E. McKenney Jun 29, 2020

rcu: Introduce 2 arg kvfree_rcu() interface



kvmalloc() can allocate two types of objects: SLAB backed
and vmalloc backed. How it behaves depends on requested
object's size and memory pressure.

Add a kvfree_rcu() interface that can free memory allocated
via kvmalloc(). It is a simple alias to kfree_rcu() which
can now handle either type of object.

<snip>
    struct test_kvfree_rcu {
        struct rcu_head rcu;
        unsigned char array[100];
    };

    struct test_kvfree_rcu *p;

    p = kvmalloc(10 * PAGE_SIZE);
    if (p)
        kvfree_rcu(p, rcu);
<snip>

Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Co-developed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

parent e0feed08

include/linux/rcupdate.h

+9 −0

Original line number	Diff line number	Diff line
		@@ -875,6 +875,15 @@ do { \
		__kvfree_rcu(&((___p)->rhf), offsetof(typeof(*(ptr)), rhf)); \
		} while (0)

		/**
		* kvfree_rcu() - kvfree an object after a grace period.
		* @ptr: pointer to kvfree
		* @rhf: the name of the struct rcu_head within the type of @ptr.
		*
		* Same as kfree_rcu(), just simple alias.
		*/
		#define kvfree_rcu(ptr, rhf) kfree_rcu(ptr, rhf)

		/*
		* Place this after a lock-acquisition primitive to guarantee that
		* an UNLOCK+LOCK pair acts as a full barrier. This guarantee applies

Admin message