[PATCH RFC tip/core/rcu 0/4] Forbid static SRCU use in modules
Mathieu Desnoyers
mathieu.desnoyers at efficios.com
Tue Apr 2 15:14:40 UTC 2019
----- On Apr 2, 2019, at 10:28 AM, paulmck paulmck at linux.ibm.com wrote:
> Hello!
>
> This series prohibits use of DEFINE_SRCU() and DEFINE_STATIC_SRCU()
> by loadable modules. The reason for this prohibition is the fact
> that using these two macros within modules requires that the size of
> the reserved region be increased, which is not something we want to
> be doing all that often. Instead, loadable modules should define an
> srcu_struct and invoke init_srcu_struct() from their module_init function
> and cleanup_srcu_struct() from their module_exit function. Note that
> modules using call_srcu() will also need to invoke srcu_barrier() from
> their module_exit function.
This arbitrary API limitation seems weird.
Isn't there a way to allow modules to use DEFINE_SRCU and DEFINE_STATIC_SRCU
while implementing them with dynamic allocation under the hood ?
Thanks,
Mathieu
>
> This series consist of the following:
>
> 1. Dynamically allocate dax_srcu.
>
> 2. Dynamically allocate drm_unplug_srcu.
>
> 3. Dynamically allocate kfd_processes_srcu.
>
> These build and have been subjected to 0day testing, but might also need
> testing by someone having the requisite hardware.
>
> Thanx, Paul
>
> ------------------------------------------------------------------------
>
> drivers/dax/super.c | 10 +++++-
> drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c | 5 +++
> drivers/gpu/drm/amd/amdkfd/kfd_process.c | 2 -
> drivers/gpu/drm/drm_drv.c | 8 ++++
> include/linux/srcutree.h | 19 +++++++++--
> kernel/rcu/rcuperf.c | 40 +++++++++++++++++++-----
> kernel/rcu/rcutorture.c | 48 +++++++++++++++++++++--------
> 7 files changed, 105 insertions(+), 27 deletions(-)
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
More information about the dri-devel
mailing list