diskutil: ensure that we lock around disk_list access

And also ensure that before we free the disk util structures,
we wait for the disk util thread to exit.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/backend.c b/backend.c
index e1dc0ac8b154a662866eea6ecc381921f5000cf0..9cc8dbc3ce1e029b4729e23e150428e4217b60e4 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -50,6 +50,7 @@
 #include "server.h"
 
 static pthread_t disk_util_thread;
+static struct fio_mutex *disk_thread_mutex;
 static struct fio_mutex *startup_mutex;
 static struct fio_mutex *writeout_mutex;
 static struct flist_head *cgroup_list;
@@ -1588,20 +1589,28 @@ static void run_threads(void)
        fio_unpin_memory();
 }
 
+void wait_for_disk_thread_exit(void)
+{
+       fio_mutex_down(disk_thread_mutex);
+}
+
 static void *disk_thread_main(void *data)
 {
+       int ret = 0;
+
        fio_mutex_up(startup_mutex);
 
-       while (threads) {
+       while (threads && !ret) {
                usleep(DISK_UTIL_MSEC * 1000);
                if (!threads)
                        break;
-               update_io_ticks();
+               ret = update_io_ticks();
 
                if (!is_backend)
                        print_thread_status();
        }
 
+       fio_mutex_up(disk_thread_mutex);
        return NULL;
 }
 
@@ -1609,14 +1618,20 @@ static int create_disk_util_thread(void)
 {
        int ret;
 
+       setup_disk_util();
+
+       disk_thread_mutex = fio_mutex_init(0);
+
        ret = pthread_create(&disk_util_thread, NULL, disk_thread_main, NULL);
        if (ret) {
+               fio_mutex_remove(disk_thread_mutex);
                log_err("Can't create disk util thread: %s\n", strerror(ret));
                return 1;
        }
 
        ret = pthread_detach(disk_util_thread);
        if (ret) {
+               fio_mutex_remove(disk_thread_mutex);
                log_err("Can't detatch disk util thread: %s\n", strerror(ret));
                return 1;
        }
@@ -1680,5 +1695,6 @@ int fio_backend(void)
 
        fio_mutex_remove(startup_mutex);
        fio_mutex_remove(writeout_mutex);
+       fio_mutex_remove(disk_thread_mutex);
        return exit_value;
 }

diff --git a/diskutil.c b/diskutil.c
index feb88526bbb90af4d67fbcec8b038c2305328ec2..32616b75848192cadd7412df379709cb72c8ec04 100644 (file)
--- a/diskutil.c
+++ b/diskutil.c
@@ -14,6 +14,9 @@
 static int last_majdev, last_mindev;
 static struct disk_util *last_du;
 
+static struct fio_mutex *disk_util_mutex;
+static int disk_util_exit;
+
 FLIST_HEAD(disk_list);
 
 static struct disk_util *__init_per_file_disk_util(struct thread_data *td,
@@ -102,17 +105,26 @@ static void update_io_tick_disk(struct disk_util *du)
        memcpy(ldus, &__dus, sizeof(__dus));
 }
 
-void update_io_ticks(void)
+int update_io_ticks(void)
 {
        struct flist_head *entry;
        struct disk_util *du;
+       int ret = 0;
 
        dprint(FD_DISKUTIL, "update io ticks\n");
 
-       flist_for_each(entry, &disk_list) {
-               du = flist_entry(entry, struct disk_util, list);
-               update_io_tick_disk(du);
-       }
+       fio_mutex_down(disk_util_mutex);
+
+       if (!disk_util_exit) {
+               flist_for_each(entry, &disk_list) {
+                       du = flist_entry(entry, struct disk_util, list);
+                       update_io_tick_disk(du);
+               }
+       } else
+               ret = 1;
+
+       fio_mutex_up(disk_util_mutex);
+       return ret;
 }
 
 static struct disk_util *disk_util_exists(int major, int minor)
@@ -276,6 +288,8 @@ static struct disk_util *disk_util_add(struct thread_data *td, int majdev,
        du->lock = fio_mutex_init(1);
        du->users = 0;
 
+       fio_mutex_down(disk_util_mutex);
+
        flist_for_each(entry, &disk_list) {
                __du = flist_entry(entry, struct disk_util, list);
 
@@ -283,6 +297,7 @@ static struct disk_util *disk_util_add(struct thread_data *td, int majdev,
 
                if (!strcmp((char *) du->dus.name, (char *) __du->dus.name)) {
                        disk_util_free(du);
+                       fio_mutex_up(disk_util_mutex);
                        return __du;
                }
        }
@@ -294,6 +309,7 @@ static struct disk_util *disk_util_add(struct thread_data *td, int majdev,
 
        flist_add_tail(&du->list, &disk_list);
        find_add_disk_slaves(td, path, du);
+       fio_mutex_up(disk_util_mutex);
        return du;
 }
 
@@ -521,6 +537,11 @@ void free_disk_util(void)
 {
        struct disk_util *du;
 
+       disk_util_exit = 1;
+       wait_for_disk_thread_exit();
+
+       fio_mutex_down(disk_util_mutex);
+
        while (!flist_empty(&disk_list)) {
                du = flist_entry(disk_list.next, struct disk_util, list);
                flist_del(&du->list);
@@ -528,6 +549,8 @@ void free_disk_util(void)
        }
 
        last_majdev = last_mindev = -1;
+       fio_mutex_up(disk_util_mutex);
+       fio_mutex_remove(disk_util_mutex);
 }
 
 void print_disk_util(struct disk_util_stat *dus, struct disk_util_agg *agg,
@@ -573,8 +596,12 @@ void show_disk_util(int terse)
        struct flist_head *entry;
        struct disk_util *du;
 
-       if (flist_empty(&disk_list))
+       fio_mutex_down(disk_util_mutex);
+
+       if (flist_empty(&disk_list)) {
+               fio_mutex_up(disk_util_mutex);
                return;
+       }
 
        if (!terse)
                log_info("\nDisk stats (read/write):\n");
@@ -585,4 +612,11 @@ void show_disk_util(int terse)
                aggregate_slaves_stats(du);
                print_disk_util(&du->dus, &du->agg, terse);
        }
+
+       fio_mutex_up(disk_util_mutex);
+}
+
+void setup_disk_util(void)
+{
+       disk_util_mutex = fio_mutex_init(1);
 }

diff --git a/diskutil.h b/diskutil.h
index 5a9b079661023487642179b84dfad0b8b3d330e0..88dde555c4cae68f07c87c828ad543e0e4ea85fb 100644 (file)
--- a/diskutil.h
+++ b/diskutil.h
@@ -94,6 +94,8 @@ static inline void disk_util_dec(struct disk_util *du)
 
 extern struct flist_head disk_list;
 
+extern void wait_for_disk_thread_exit(void);
+
 /*
  * disk util stuff
  */
@@ -102,13 +104,18 @@ extern void print_disk_util(struct disk_util_stat *, struct disk_util_agg *, int
 extern void show_disk_util(int terse);
 extern void free_disk_util(void);
 extern void init_disk_util(struct thread_data *);
-extern void update_io_ticks(void);
+extern int update_io_ticks(void);
+extern void setup_disk_util(void);
 #else
 #define print_disk_util(dus, agg, terse)
 #define show_disk_util(terse)
 #define free_disk_util()
 #define init_disk_util(td)
-#define update_io_ticks()
+#define setup_disk_util()
+static inline int update_io_ticks(void)
+{
+       return 0;
+}
 #endif
 
 #endif

diff --git a/iolog.h b/iolog.h
index 95617fccb6891a92970c60cb0873e06b99d9782f..1853846edb7a2c6072e159bd9003a2c3027a6d9a 100644 (file)
--- a/iolog.h
+++ b/iolog.h
@@ -107,7 +107,6 @@ extern void add_bw_sample(struct thread_data *, enum fio_ddir, unsigned int,
 extern void add_iops_sample(struct thread_data *, enum fio_ddir, struct timeval *);
 extern void init_disk_util(struct thread_data *);
 extern void update_rusage_stat(struct thread_data *);
-extern void update_io_ticks(void);
 extern void setup_log(struct io_log **, unsigned long);
 extern void finish_log(struct thread_data *, struct io_log *, const char *);
 extern void finish_log_named(struct thread_data *, struct io_log *, const char *, const char *);