diff options
| -rw-r--r-- | drivers/gpu/msm/kgsl_device.h | 2 | ||||
| -rw-r--r-- | drivers/gpu/msm/kgsl_snapshot.c | 36 |
2 files changed, 27 insertions, 11 deletions
diff --git a/drivers/gpu/msm/kgsl_device.h b/drivers/gpu/msm/kgsl_device.h index 706de527c444..abad774d481a 100644 --- a/drivers/gpu/msm/kgsl_device.h +++ b/drivers/gpu/msm/kgsl_device.h @@ -449,6 +449,7 @@ struct kgsl_device_private { * @work: worker to dump the frozen memory * @dump_gate: completion gate signaled by worker when it is finished. * @process: the process that caused the hang, if known. + * @sysfs_read: An atomic for concurrent snapshot reads via syfs. */ struct kgsl_snapshot { u8 *start; @@ -463,6 +464,7 @@ struct kgsl_snapshot { struct work_struct work; struct completion dump_gate; struct kgsl_process_private *process; + atomic_t sysfs_read; }; /** diff --git a/drivers/gpu/msm/kgsl_snapshot.c b/drivers/gpu/msm/kgsl_snapshot.c index 8116ccaa96bd..0977d1477b6a 100644 --- a/drivers/gpu/msm/kgsl_snapshot.c +++ b/drivers/gpu/msm/kgsl_snapshot.c @@ -608,6 +608,7 @@ void kgsl_device_snapshot(struct kgsl_device *device, snapshot->start = device->snapshot_memory.ptr; snapshot->ptr = device->snapshot_memory.ptr; snapshot->remain = device->snapshot_memory.size; + atomic_set(&snapshot->sysfs_read, 0); header = (struct kgsl_snapshot_header *) snapshot->ptr; @@ -711,6 +712,8 @@ static ssize_t snapshot_show(struct file *filep, struct kobject *kobj, mutex_lock(&device->mutex); snapshot = device->snapshot; + if (snapshot != NULL) + atomic_inc(&snapshot->sysfs_read); mutex_unlock(&device->mutex); /* Return nothing if we haven't taken a snapshot yet */ @@ -722,8 +725,10 @@ static ssize_t snapshot_show(struct file *filep, struct kobject *kobj, * to allow userspace to bail if things go horribly wrong. */ ret = wait_for_completion_interruptible(&snapshot->dump_gate); - if (ret) + if (ret) { + atomic_dec(&snapshot->sysfs_read); return ret; + } obj_itr_init(&itr, buf, off, count); @@ -732,7 +737,7 @@ static ssize_t snapshot_show(struct file *filep, struct kobject *kobj, goto done; /* Dump the memory pool if it exists */ - if (device->snapshot->mempool) { + if (snapshot->mempool) { ret = obj_itr_out(&itr, snapshot->mempool, snapshot->mempool_size); if (ret == 0) @@ -751,26 +756,35 @@ static ssize_t snapshot_show(struct file *filep, struct kobject *kobj, * Make sure everything has been written out before destroying things. * The best way to confirm this is to go all the way through without * writing any bytes - so only release if we get this far and - * itr->write is 0 + * itr->write is 0 and there are no concurrent reads pending */ if (itr.write == 0) { + bool snapshot_free = false; + mutex_lock(&device->mutex); - device->snapshot = NULL; + if (atomic_dec_and_test(&snapshot->sysfs_read)) { + device->snapshot = NULL; + snapshot_free = true; + } mutex_unlock(&device->mutex); - list_for_each_entry_safe(obj, tmp, &snapshot->obj_list, node) - kgsl_snapshot_put_object(obj); + if (snapshot_free) { + list_for_each_entry_safe(obj, tmp, + &snapshot->obj_list, node) + kgsl_snapshot_put_object(obj); - if (snapshot->mempool) - vfree(snapshot->mempool); + if (snapshot->mempool) + vfree(snapshot->mempool); - kfree(snapshot); - KGSL_CORE_ERR("snapshot: objects released\n"); + kfree(snapshot); + KGSL_CORE_ERR("snapshot: objects released\n"); + } + return 0; } done: - + atomic_dec(&snapshot->sysfs_read); return itr.write; } |