[PATCH 07/10] dlm: change lock time stamping

From: David Teigland
Date: Tue Dec 23 2008 - 11:15:52 EST


Use ktime instead of jiffies for timestamping lkb's. Also stamp the
time on every lkb whenever it's added to a resource queue, instead of
just stamping locks subject to timeouts. This will allow us to use
timestamps more widely for debugging all locks.

Signed-off-by: David Teigland <teigland@xxxxxxxxxx>
---
fs/dlm/debug_fs.c | 14 +++++++-------
fs/dlm/dlm_internal.h | 2 +-
fs/dlm/lock.c | 21 +++++++++++----------
fs/dlm/netlink.c | 1 -
4 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/fs/dlm/debug_fs.c b/fs/dlm/debug_fs.c
index 8fc24f4..19e4f9e 100644
--- a/fs/dlm/debug_fs.c
+++ b/fs/dlm/debug_fs.c
@@ -162,21 +162,21 @@ static int print_resource(struct dlm_rsb *res, struct seq_file *s)

static void print_lock(struct seq_file *s, struct dlm_lkb *lkb, struct dlm_rsb *r)
{
- unsigned int waiting = 0;
- uint64_t xid = 0;
+ u64 xid = 0;
+ u64 us;

if (lkb->lkb_flags & DLM_IFL_USER) {
if (lkb->lkb_ua)
xid = lkb->lkb_ua->xid;
}

- if (lkb->lkb_timestamp)
- waiting = jiffies_to_msecs(jiffies - lkb->lkb_timestamp);
+ /* microseconds since lkb was added to current queue */
+ us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_timestamp));

- /* id nodeid remid pid xid exflags flags sts grmode rqmode time_ms
+ /* id nodeid remid pid xid exflags flags sts grmode rqmode time_us
r_nodeid r_len r_name */

- seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %u %u %d \"%s\"\n",
+ seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %llu %u %d \"%s\"\n",
lkb->lkb_id,
lkb->lkb_nodeid,
lkb->lkb_remid,
@@ -187,7 +187,7 @@ static void print_lock(struct seq_file *s, struct dlm_lkb *lkb, struct dlm_rsb *
lkb->lkb_status,
lkb->lkb_grmode,
lkb->lkb_rqmode,
- waiting,
+ (unsigned long long)us,
r->res_nodeid,
r->res_length,
r->res_name);
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index 868e4c9..e69135c 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -245,7 +245,7 @@ struct dlm_lkb {
struct list_head lkb_astqueue; /* need ast to be sent */
struct list_head lkb_ownqueue; /* list of locks for a process */
struct list_head lkb_time_list;
- unsigned long lkb_timestamp;
+ ktime_t lkb_timestamp;
unsigned long lkb_timeout_cs;

char *lkb_lvbptr;
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 7b758da..dfc57ae 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -742,6 +742,8 @@ static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)

DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););

+ lkb->lkb_timestamp = ktime_get();
+
lkb->lkb_status = status;

switch (status) {
@@ -1011,10 +1013,8 @@ static void add_timeout(struct dlm_lkb *lkb)
{
struct dlm_ls *ls = lkb->lkb_resource->res_ls;

- if (is_master_copy(lkb)) {
- lkb->lkb_timestamp = jiffies;
+ if (is_master_copy(lkb))
return;
- }

if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
@@ -1029,7 +1029,6 @@ static void add_timeout(struct dlm_lkb *lkb)
DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
mutex_lock(&ls->ls_timeout_mutex);
hold_lkb(lkb);
- lkb->lkb_timestamp = jiffies;
list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
mutex_unlock(&ls->ls_timeout_mutex);
}
@@ -1057,6 +1056,7 @@ void dlm_scan_timeout(struct dlm_ls *ls)
struct dlm_rsb *r;
struct dlm_lkb *lkb;
int do_cancel, do_warn;
+ s64 wait_us;

for (;;) {
if (dlm_locking_stopped(ls))
@@ -1067,14 +1067,15 @@ void dlm_scan_timeout(struct dlm_ls *ls)
mutex_lock(&ls->ls_timeout_mutex);
list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {

+ wait_us = ktime_to_us(ktime_sub(ktime_get(),
+ lkb->lkb_timestamp));
+
if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
- time_after_eq(jiffies, lkb->lkb_timestamp +
- lkb->lkb_timeout_cs * HZ/100))
+ wait_us >= (lkb->lkb_timeout_cs * 10000))
do_cancel = 1;

if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
- time_after_eq(jiffies, lkb->lkb_timestamp +
- dlm_config.ci_timewarn_cs * HZ/100))
+ wait_us >= dlm_config.ci_timewarn_cs * 10000)
do_warn = 1;

if (!do_cancel && !do_warn)
@@ -1120,12 +1121,12 @@ void dlm_scan_timeout(struct dlm_ls *ls)
void dlm_adjust_timeouts(struct dlm_ls *ls)
{
struct dlm_lkb *lkb;
- long adj = jiffies - ls->ls_recover_begin;
+ u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);

ls->ls_recover_begin = 0;
mutex_lock(&ls->ls_timeout_mutex);
list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
- lkb->lkb_timestamp += adj;
+ lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
mutex_unlock(&ls->ls_timeout_mutex);
}

diff --git a/fs/dlm/netlink.c b/fs/dlm/netlink.c
index 18bda83..46e582c 100644
--- a/fs/dlm/netlink.c
+++ b/fs/dlm/netlink.c
@@ -115,7 +115,6 @@ static void fill_data(struct dlm_lock_data *data, struct dlm_lkb *lkb)
data->status = lkb->lkb_status;
data->grmode = lkb->lkb_grmode;
data->rqmode = lkb->lkb_rqmode;
- data->timestamp = lkb->lkb_timestamp;
if (lkb->lkb_ua)
data->xid = lkb->lkb_ua->xid;
if (r) {
--
1.5.5.1

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