On 3/12/23 10:59, Mike Rapoport wrote: > On Fri, Mar 10, 2023 at 11:32:09AM +0100, Vlastimil Babka wrote: >> This will make it easier to free objects in situations when they can >> come from either kmalloc() or kmem_cache_alloc(), and also allow >> kfree_rcu() for freeing objects from kmem_cache_alloc(). >> >> For the SLAB and SLUB allocators this was always possible so with SLOB >> gone, we can document it as supported. >> >> Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx> >> Cc: Mike Rapoport <rppt@xxxxxxxxxx> >> Cc: Jonathan Corbet <corbet@xxxxxxx> >> Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx> >> Cc: Frederic Weisbecker <frederic@xxxxxxxxxx> >> Cc: Neeraj Upadhyay <quic_neeraju@xxxxxxxxxxx> >> Cc: Josh Triplett <josh@xxxxxxxxxxxxxxxx> >> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> >> Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> >> Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx> >> Cc: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx> >> --- >> Documentation/core-api/memory-allocation.rst | 15 +++++++++++---- >> include/linux/rcupdate.h | 6 ++++-- >> mm/slab_common.c | 5 +---- >> 3 files changed, 16 insertions(+), 10 deletions(-) >> >> diff --git a/Documentation/core-api/memory-allocation.rst b/Documentation/core-api/memory-allocation.rst >> index 5954ddf6ee13..f9e8d352ed67 100644 >> --- a/Documentation/core-api/memory-allocation.rst >> +++ b/Documentation/core-api/memory-allocation.rst >> @@ -170,7 +170,14 @@ should be used if a part of the cache might be copied to the userspace. >> After the cache is created kmem_cache_alloc() and its convenience >> wrappers can allocate memory from that cache. >> >> -When the allocated memory is no longer needed it must be freed. You can >> -use kvfree() for the memory allocated with `kmalloc`, `vmalloc` and >> -`kvmalloc`. The slab caches should be freed with kmem_cache_free(). And >> -don't forget to destroy the cache with kmem_cache_destroy(). >> +When the allocated memory is no longer needed it must be freed. Objects > > I'd add a line break before Objects ^ > >> +allocated by `kmalloc` can be freed by `kfree` or `kvfree`. >> +Objects allocated by `kmem_cache_alloc` can be freed with `kmem_cache_free` >> +or also by `kfree` or `kvfree`, which can be more convenient as it does > > Maybe replace 'or also by' with a coma: > > Objects allocated by `kmem_cache_alloc` can be freed with `kmem_cache_free`, > `kfree` or `kvfree`, which can be more convenient as it does But then I need to clarify what the "which" applies to? > >> +not require the kmem_cache pointed. > > ^ pointer. > >> +The rules for _bulk and _rcu flavors of freeing functions are analogical. > > Maybe > > The same rules apply to _bulk and _rcu flavors of freeing functions. So like this incremental diff? diff --git a/Documentation/core-api/memory-allocation.rst b/Documentation/core-api/memory-allocation.rst index f9e8d352ed67..1c58d883b273 100644 --- a/Documentation/core-api/memory-allocation.rst +++ b/Documentation/core-api/memory-allocation.rst @@ -170,12 +170,14 @@ should be used if a part of the cache might be copied to the userspace. After the cache is created kmem_cache_alloc() and its convenience wrappers can allocate memory from that cache. -When the allocated memory is no longer needed it must be freed. Objects -allocated by `kmalloc` can be freed by `kfree` or `kvfree`. -Objects allocated by `kmem_cache_alloc` can be freed with `kmem_cache_free` -or also by `kfree` or `kvfree`, which can be more convenient as it does -not require the kmem_cache pointed. -The rules for _bulk and _rcu flavors of freeing functions are analogical. +When the allocated memory is no longer needed it must be freed. + +Objects allocated by `kmalloc` can be freed by `kfree` or `kvfree`. Objects +allocated by `kmem_cache_alloc` can be freed with `kmem_cache_free`, `kfree` +or `kvfree`, where the latter two might be more convenient thanks to not +needing the kmem_cache pointer. + +The same rules apply to _bulk and _rcu flavors of freeing functions. Memory allocated by `vmalloc` can be freed with `vfree` or `kvfree`. Memory allocated by `kvmalloc` can be freed with `kvfree`.
