diff options
| author | Felix Kuehling <Felix.Kuehling@amd.com> | 2018-07-11 22:32:44 -0400 |
|---|---|---|
| committer | Oded Gabbay <oded.gabbay@gmail.com> | 2018-07-11 22:32:44 -0400 |
| commit | efeaed4d98eb4dc9ce01e1dca6d3778d180b272c (patch) | |
| tree | c86bc91ff25f05acbc6071d8cb7df8e529ccf91b /drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h | |
| parent | 0337976f40b0a9605c24797762b95b3414619d71 (diff) | |
| download | linux-efeaed4d98eb4dc9ce01e1dca6d3778d180b272c.tar.bz2 | |
drm/amdkfd: Reliably prevent reclaim-FS while holding DQM lock
This is needed to prevent deadlocks when MMU notifiers run in
reclaim-FS context and take the DQM lock for userptr evictions.
Previously this was done by making all memory allocations under
DQM locks GFP_NOIO. This is error prone. Using
memalloc_nofs_save/restore will reliably affect all memory
allocations anywhere in the kernel while the DQM lock is held.
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Diffstat (limited to 'drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h')
| -rw-r--r-- | drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h index 59a6b1956932..0a23ddac345e 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h +++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.h @@ -26,6 +26,8 @@ #include <linux/rwsem.h> #include <linux/list.h> +#include <linux/mutex.h> +#include <linux/sched/mm.h> #include "kfd_priv.h" #include "kfd_mqd_manager.h" @@ -173,8 +175,9 @@ struct device_queue_manager { struct mqd_manager *mqds[KFD_MQD_TYPE_MAX]; struct packet_manager packets; struct kfd_dev *dev; - struct mutex lock; + struct mutex lock_hidden; /* use dqm_lock/unlock(dqm) */ struct list_head queues; + unsigned int saved_flags; unsigned int processes_count; unsigned int queue_count; unsigned int sdma_queue_count; @@ -219,4 +222,19 @@ get_sh_mem_bases_nybble_64(struct kfd_process_device *pdd) return (pdd->lds_base >> 60) & 0x0E; } +/* The DQM lock can be taken in MMU notifiers. Make sure no reclaim-FS + * happens while holding this lock anywhere to prevent deadlocks when + * an MMU notifier runs in reclaim-FS context. + */ +static inline void dqm_lock(struct device_queue_manager *dqm) +{ + mutex_lock(&dqm->lock_hidden); + dqm->saved_flags = memalloc_nofs_save(); +} +static inline void dqm_unlock(struct device_queue_manager *dqm) +{ + memalloc_nofs_restore(dqm->saved_flags); + mutex_unlock(&dqm->lock_hidden); +} + #endif /* KFD_DEVICE_QUEUE_MANAGER_H_ */ |