bindings: cleanup cache locking

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/bindings.c b/src/bindings.c
index b89e28f20172064c954bac143dfe1778f84d91bc..42f5aa7aae0dce92bccc58745f3c3c0b3a5bef3f 100644 (file)
--- a/src/bindings.c
+++ b/src/bindings.c
@@ -98,7 +98,7 @@ struct pidns_init_store {
 static struct pidns_init_store *pidns_hash_table[PIDNS_HASH_SIZE];
 static pthread_mutex_t pidns_store_mutex = PTHREAD_MUTEX_INITIALIZER;
 
-static void lock_mutex(pthread_mutex_t *l)
+static void mutex_lock(pthread_mutex_t *l)
 {
        int ret;
 
@@ -109,7 +109,7 @@ static void lock_mutex(pthread_mutex_t *l)
 
 struct cgroup_ops *cgroup_ops;
 
-static void unlock_mutex(pthread_mutex_t *l)
+static void mutex_unlock(pthread_mutex_t *l)
 {
        int ret;
 
@@ -118,17 +118,14 @@ static void unlock_mutex(pthread_mutex_t *l)
                log_exit("%s - returned %d\n", strerror(ret), ret);
 }
 
-static inline void unlock_mutex_function(pthread_mutex_t **mutex)
+static inline void store_lock(void)
 {
-       if (*mutex)
-               unlock_mutex(*mutex);
+       mutex_lock(&pidns_store_mutex);
 }
-#define __do_unlock call_cleaner(unlock_mutex)
 
-static pthread_mutex_t* __attribute__((warn_unused_result)) store_lock(void)
+static inline void store_unlock(void)
 {
-       lock_mutex(&pidns_store_mutex);
-       return &pidns_store_mutex;
+       mutex_unlock(&pidns_store_mutex);
 }
 
 /* /proc/       =    6
@@ -435,18 +432,16 @@ out:
 
 pid_t lookup_initpid_in_store(pid_t pid)
 {
-       __do_unlock pthread_mutex_t *store_mutex = NULL;
        pid_t answer = 0;
        char path[LXCFS_PROC_PID_NS_LEN];
        struct stat st;
        struct pidns_init_store *entry;
 
        snprintf(path, sizeof(path), "/proc/%d/ns/pid", pid);
-
        if (stat(path, &st))
-               goto out;
+               return ret_errno(ESRCH);
 
-       store_mutex = store_lock();
+       store_lock();
 
        entry = lookup_verify_initpid(st.st_ino);
        if (entry) {
@@ -455,9 +450,11 @@ pid_t lookup_initpid_in_store(pid_t pid)
        }
 
        /* release the mutex as the following call is expensive */
-       unlock_mutex(move_ptr(store_mutex));
+       store_unlock();
+
        answer = get_init_pid_for_task(pid);
-       store_mutex = store_lock();
+
+       store_lock();
 
        if (answer > 0)
                save_initpid(st.st_ino, answer);
@@ -468,6 +465,7 @@ out:
         * return.
         */
        prune_initpid_store();
+       store_unlock();
 
        return answer;
 }