With the new channel allocation model, multiple threads can be allocating channels simultaneously. Therefore we need to add a lock around the code.
Signed-off-by: Mikko Perttunen mperttunen@nvidia.com --- drivers/gpu/host1x/channel.c | 7 +++++++ drivers/gpu/host1x/channel.h | 2 ++ 2 files changed, 9 insertions(+)
diff --git a/drivers/gpu/host1x/channel.c b/drivers/gpu/host1x/channel.c index 2fb93c27c1d9..9d8cad12f9d8 100644 --- a/drivers/gpu/host1x/channel.c +++ b/drivers/gpu/host1x/channel.c @@ -42,6 +42,8 @@ int host1x_channel_list_init(struct host1x_channel_list *chlist,
bitmap_zero(chlist->allocated_channels, num_channels);
+ mutex_init(&chlist->lock); + return 0; }
@@ -111,8 +113,11 @@ static struct host1x_channel *acquire_unused_channel(struct host1x *host) unsigned int max_channels = host->info->nb_channels; unsigned int index;
+ mutex_lock(&chlist->lock); + index = find_first_zero_bit(chlist->allocated_channels, max_channels); if (index >= max_channels) { + mutex_unlock(&chlist->lock); dev_err(host->dev, "failed to find free channel\n"); return NULL; } @@ -121,6 +126,8 @@ static struct host1x_channel *acquire_unused_channel(struct host1x *host)
set_bit(index, chlist->allocated_channels);
+ mutex_unlock(&chlist->lock); + return &chlist->channels[index]; }
diff --git a/drivers/gpu/host1x/channel.h b/drivers/gpu/host1x/channel.h index 7068e42d42df..e68a8ae9a670 100644 --- a/drivers/gpu/host1x/channel.h +++ b/drivers/gpu/host1x/channel.h @@ -29,6 +29,8 @@ struct host1x_channel;
struct host1x_channel_list { struct host1x_channel *channels; + + struct mutex lock; unsigned long *allocated_channels; };