diff options
Diffstat (limited to 'drivers/interconnect/core.c')
| -rw-r--r-- | drivers/interconnect/core.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c index 14d785e5629e..aadb2b97498a 100644 --- a/drivers/interconnect/core.c +++ b/drivers/interconnect/core.c @@ -13,6 +13,7 @@ #include <linux/interconnect.h> #include <linux/interconnect-provider.h> #include <linux/list.h> +#include <linux/sched/mm.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/slab.h> @@ -29,6 +30,7 @@ static LIST_HEAD(icc_providers); static int providers_count; static bool synced_state; static DEFINE_MUTEX(icc_lock); +static DEFINE_MUTEX(icc_bw_lock); static struct dentry *icc_debugfs_dir; static void icc_summary_show_one(struct seq_file *s, struct icc_node *n) @@ -380,6 +382,9 @@ struct icc_node_data *of_icc_get_from_provider(struct of_phandle_args *spec) } mutex_unlock(&icc_lock); + if (!node) + return ERR_PTR(-EINVAL); + if (IS_ERR(node)) return ERR_CAST(node); @@ -632,7 +637,7 @@ int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw) if (WARN_ON(IS_ERR(path) || !path->num_nodes)) return -EINVAL; - mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); old_avg = path->reqs[0].avg_bw; old_peak = path->reqs[0].peak_bw; @@ -664,7 +669,7 @@ int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw) apply_constraints(path); } - mutex_unlock(&icc_lock); + mutex_unlock(&icc_bw_lock); trace_icc_set_bw_end(path, ret); @@ -967,6 +972,7 @@ void icc_node_add(struct icc_node *node, struct icc_provider *provider) return; mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); node->provider = provider; list_add_tail(&node->node_list, &provider->nodes); @@ -992,6 +998,7 @@ void icc_node_add(struct icc_node *node, struct icc_provider *provider) node->avg_bw = 0; node->peak_bw = 0; + mutex_unlock(&icc_bw_lock); mutex_unlock(&icc_lock); } EXPORT_SYMBOL_GPL(icc_node_add); @@ -1119,6 +1126,7 @@ void icc_sync_state(struct device *dev) return; mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); synced_state = true; list_for_each_entry(p, &icc_providers, provider_list) { dev_dbg(p->dev, "interconnect provider is in synced state\n"); @@ -1131,13 +1139,21 @@ void icc_sync_state(struct device *dev) } } } + mutex_unlock(&icc_bw_lock); mutex_unlock(&icc_lock); } EXPORT_SYMBOL_GPL(icc_sync_state); static int __init icc_init(void) { - struct device_node *root = of_find_node_by_path("/"); + struct device_node *root; + + /* Teach lockdep about lock ordering wrt. shrinker: */ + fs_reclaim_acquire(GFP_KERNEL); + might_lock(&icc_bw_lock); + fs_reclaim_release(GFP_KERNEL); + + root = of_find_node_by_path("/"); providers_count = of_count_icc_providers(root); of_node_put(root); |