s390/dasd: add locking for global_profile access
Access to DASDs global statistics is done without locking which
can lead to inconsistent data. Add locking to fix this. Also move
the relevant structs in a global dasd_profile struct.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd_proc.c b/drivers/s390/block/dasd_proc.c
index 78ac905a..7641008 100644
--- a/drivers/s390/block/dasd_proc.c
+++ b/drivers/s390/block/dasd_proc.c
@@ -219,7 +219,8 @@
"/proc/dasd/statistics'\n");
return 0;
}
- prof = &dasd_global_profile_data;
+ spin_lock_bh(&dasd_global_profile.lock);
+ prof = dasd_global_profile.data;
/* prevent counter 'overflow' on output */
for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
@@ -255,6 +256,7 @@
dasd_statistics_array(m, prof->dasd_io_time3, factor);
seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
+ spin_unlock_bh(&dasd_global_profile.lock);
#else
seq_printf(m, "Statistics are not activated in this kernel\n");
#endif