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authorSebastian Ott <sebott@linux.vnet.ibm.com>2015-01-28 18:44:17 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2015-01-29 09:19:27 +0100
commit8ea55c95c372a7a51fa50cb7c75240bfbe8bd337 (patch)
treea7a496ce7f0f0ae9a417d50acb44fb9fe1229ff9 /drivers/s390
parente6d60b368b45b9be3aa068f8e5fa98c3487c9d4e (diff)
downloadlinux-8ea55c95c372a7a51fa50cb7c75240bfbe8bd337.tar.bz2
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>
Diffstat (limited to 'drivers/s390')
-rw-r--r--drivers/s390/block/dasd.c32
-rw-r--r--drivers/s390/block/dasd_int.h2
-rw-r--r--drivers/s390/block/dasd_proc.c4
3 files changed, 24 insertions, 14 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 4abf11965484..a67e8dae73c3 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -674,8 +674,12 @@ EXPORT_SYMBOL(dasd_enable_device);
unsigned int dasd_global_profile_level = DASD_PROFILE_OFF;
#ifdef CONFIG_DASD_PROFILE
-struct dasd_profile_info dasd_global_profile_data;
-static struct dentry *dasd_global_profile_dentry;
+static struct dasd_profile_info dasd_global_profile_data;
+struct dasd_profile dasd_global_profile = {
+ .dentry = NULL,
+ .data = &dasd_global_profile_data,
+ .lock = __SPIN_LOCK_UNLOCKED(dasd_global_profile.lock),
+};
static struct dentry *dasd_debugfs_global_entry;
/*
@@ -696,11 +700,13 @@ static void dasd_profile_start(struct dasd_block *block,
if (++counter >= 31)
break;
+ spin_lock(&dasd_global_profile.lock);
if (dasd_global_profile_level) {
- dasd_global_profile_data.dasd_io_nr_req[counter]++;
+ dasd_global_profile.data->dasd_io_nr_req[counter]++;
if (rq_data_dir(req) == READ)
- dasd_global_profile_data.dasd_read_nr_req[counter]++;
+ dasd_global_profile.data->dasd_read_nr_req[counter]++;
}
+ spin_unlock(&dasd_global_profile.lock);
spin_lock(&block->profile.lock);
if (block->profile.data) {
@@ -825,8 +831,9 @@ static void dasd_profile_end(struct dasd_block *block,
dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
dasd_profile_counter(endtime, endtime_ind);
+ spin_lock(&dasd_global_profile.lock);
if (dasd_global_profile_level) {
- dasd_profile_end_add_data(&dasd_global_profile_data,
+ dasd_profile_end_add_data(dasd_global_profile.data,
cqr->startdev != block->base,
cqr->cpmode == 1,
rq_data_dir(req) == READ,
@@ -835,6 +842,7 @@ static void dasd_profile_end(struct dasd_block *block,
irqtime_ind, irqtimeps_ind,
endtime_ind);
}
+ spin_unlock(&dasd_global_profile.lock);
spin_lock(&block->profile.lock);
if (block->profile.data)
@@ -878,8 +886,7 @@ void dasd_profile_reset(struct dasd_profile *profile)
void dasd_global_profile_reset(void)
{
- memset(&dasd_global_profile_data, 0, sizeof(dasd_global_profile_data));
- getnstimeofday(&dasd_global_profile_data.starttod);
+ dasd_profile_reset(&dasd_global_profile);
}
int dasd_profile_on(struct dasd_profile *profile)
@@ -1077,7 +1084,9 @@ static int dasd_stats_global_show(struct seq_file *m, void *v)
seq_puts(m, "disabled\n");
return 0;
}
- dasd_stats_seq_print(m, &dasd_global_profile_data);
+ spin_lock_bh(&dasd_global_profile.lock);
+ dasd_stats_seq_print(m, dasd_global_profile.data);
+ spin_unlock_bh(&dasd_global_profile.lock);
return 0;
}
@@ -1123,8 +1132,8 @@ static void dasd_profile_exit(struct dasd_profile *profile)
static void dasd_statistics_removeroot(void)
{
dasd_global_profile_level = DASD_PROFILE_OFF;
- debugfs_remove(dasd_global_profile_dentry);
- dasd_global_profile_dentry = NULL;
+ debugfs_remove(dasd_global_profile.dentry);
+ dasd_global_profile.dentry = NULL;
debugfs_remove(dasd_debugfs_global_entry);
debugfs_remove(dasd_debugfs_root_entry);
}
@@ -1136,7 +1145,6 @@ static void dasd_statistics_createroot(void)
dasd_debugfs_root_entry = NULL;
dasd_debugfs_global_entry = NULL;
- dasd_global_profile_dentry = NULL;
pde = debugfs_create_dir("dasd", NULL);
if (!pde || IS_ERR(pde))
goto error;
@@ -1151,7 +1159,7 @@ static void dasd_statistics_createroot(void)
NULL, &dasd_stats_global_fops);
if (!pde || IS_ERR(pde))
goto error;
- dasd_global_profile_dentry = pde;
+ dasd_global_profile.dentry = pde;
return;
error:
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 8b5d4100abf7..91731fa05604 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -651,7 +651,7 @@ dasd_check_blocksize(int bsize)
#define DASD_PROFILE_GLOBAL_ONLY 2
extern debug_info_t *dasd_debug_area;
-extern struct dasd_profile_info dasd_global_profile_data;
+extern struct dasd_profile dasd_global_profile;
extern unsigned int dasd_global_profile_level;
extern const struct block_device_operations dasd_device_operations;
diff --git a/drivers/s390/block/dasd_proc.c b/drivers/s390/block/dasd_proc.c
index 78ac905a5b7f..76410084c48f 100644
--- a/drivers/s390/block/dasd_proc.c
+++ b/drivers/s390/block/dasd_proc.c
@@ -219,7 +219,8 @@ static int dasd_stats_proc_show(struct seq_file *m, void *v)
"/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 @@ static int dasd_stats_proc_show(struct seq_file *m, void *v)
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