* [Cluster-devel] [PATCH 2/2] dlm: replace usage of found with dedicated list iterator variable
2022-03-31 22:00 [Cluster-devel] [PATCH 1/2] dlm: remove usage of list iterator for list_add() after the loop body Jakob Koschel
@ 2022-03-31 22:00 ` Jakob Koschel
0 siblings, 0 replies; 2+ messages in thread
From: Jakob Koschel @ 2022-03-31 22:00 UTC (permalink / raw)
To: cluster-devel.redhat.com
To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.
To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].
This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w at mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
---
fs/dlm/lock.c | 53 +++++++++++++++++++++++-------------------------
fs/dlm/plock.c | 25 ++++++++++++-----------
fs/dlm/recover.c | 35 ++++++++++++++++----------------
3 files changed, 55 insertions(+), 58 deletions(-)
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 66e92617d7ea..729c1ca8824f 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -1870,7 +1870,7 @@ static void del_timeout(struct dlm_lkb *lkb)
void dlm_scan_timeout(struct dlm_ls *ls)
{
struct dlm_rsb *r;
- struct dlm_lkb *lkb;
+ struct dlm_lkb *lkb = NULL, *iter;
int do_cancel, do_warn;
s64 wait_us;
@@ -1881,27 +1881,28 @@ void dlm_scan_timeout(struct dlm_ls *ls)
do_cancel = 0;
do_warn = 0;
mutex_lock(&ls->ls_timeout_mutex);
- list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
+ list_for_each_entry(iter, &ls->ls_timeout, lkb_time_list) {
wait_us = ktime_to_us(ktime_sub(ktime_get(),
- lkb->lkb_timestamp));
+ iter->lkb_timestamp));
- if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
- wait_us >= (lkb->lkb_timeout_cs * 10000))
+ if ((iter->lkb_exflags & DLM_LKF_TIMEOUT) &&
+ wait_us >= (iter->lkb_timeout_cs * 10000))
do_cancel = 1;
- if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
+ if ((iter->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
wait_us >= dlm_config.ci_timewarn_cs * 10000)
do_warn = 1;
if (!do_cancel && !do_warn)
continue;
- hold_lkb(lkb);
+ hold_lkb(iter);
+ lkb = iter;
break;
}
mutex_unlock(&ls->ls_timeout_mutex);
- if (!do_cancel && !do_warn)
+ if (!lkb)
break;
r = lkb->lkb_resource;
@@ -5261,21 +5262,18 @@ void dlm_recover_waiters_pre(struct dlm_ls *ls)
static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
{
- struct dlm_lkb *lkb;
- int found = 0;
+ struct dlm_lkb *lkb = NULL, *iter;
mutex_lock(&ls->ls_waiters_mutex);
- list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
- if (lkb->lkb_flags & DLM_IFL_RESEND) {
- hold_lkb(lkb);
- found = 1;
+ list_for_each_entry(iter, &ls->ls_waiters, lkb_wait_reply) {
+ if (iter->lkb_flags & DLM_IFL_RESEND) {
+ hold_lkb(iter);
+ lkb = iter;
break;
}
}
mutex_unlock(&ls->ls_waiters_mutex);
- if (!found)
- lkb = NULL;
return lkb;
}
@@ -5929,37 +5927,36 @@ int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
int mode, uint32_t flags, void *name, unsigned int namelen,
unsigned long timeout_cs, uint32_t *lkid)
{
- struct dlm_lkb *lkb;
+ struct dlm_lkb *lkb = NULL, *iter;
struct dlm_user_args *ua;
int found_other_mode = 0;
- int found = 0;
int rv = 0;
mutex_lock(&ls->ls_orphans_mutex);
- list_for_each_entry(lkb, &ls->ls_orphans, lkb_ownqueue) {
- if (lkb->lkb_resource->res_length != namelen)
+ list_for_each_entry(iter, &ls->ls_orphans, lkb_ownqueue) {
+ if (iter->lkb_resource->res_length != namelen)
continue;
- if (memcmp(lkb->lkb_resource->res_name, name, namelen))
+ if (memcmp(iter->lkb_resource->res_name, name, namelen))
continue;
- if (lkb->lkb_grmode != mode) {
+ if (iter->lkb_grmode != mode) {
found_other_mode = 1;
continue;
}
- found = 1;
- list_del_init(&lkb->lkb_ownqueue);
- lkb->lkb_flags &= ~DLM_IFL_ORPHAN;
- *lkid = lkb->lkb_id;
+ lkb = iter;
+ list_del_init(&iter->lkb_ownqueue);
+ iter->lkb_flags &= ~DLM_IFL_ORPHAN;
+ *lkid = iter->lkb_id;
break;
}
mutex_unlock(&ls->ls_orphans_mutex);
- if (!found && found_other_mode) {
+ if (!lkb && found_other_mode) {
rv = -EAGAIN;
goto out;
}
- if (!found) {
+ if (!lkb) {
rv = -ENOENT;
goto out;
}
diff --git a/fs/dlm/plock.c b/fs/dlm/plock.c
index c38b2b8ffd1d..c7ac0377822c 100644
--- a/fs/dlm/plock.c
+++ b/fs/dlm/plock.c
@@ -419,8 +419,8 @@ static ssize_t dev_write(struct file *file, const char __user *u, size_t count,
loff_t *ppos)
{
struct dlm_plock_info info;
- struct plock_op *op;
- int found = 0, do_callback = 0;
+ struct plock_op *op = NULL, *iter;
+ int do_callback = 0;
if (count != sizeof(info))
return -EINVAL;
@@ -432,24 +432,25 @@ static ssize_t dev_write(struct file *file, const char __user *u, size_t count,
return -EINVAL;
spin_lock(&ops_lock);
- list_for_each_entry(op, &recv_list, list) {
- if (op->info.fsid == info.fsid &&
- op->info.number == info.number &&
- op->info.owner == info.owner) {
- struct plock_xop *xop = (struct plock_xop *)op;
- list_del_init(&op->list);
- memcpy(&op->info, &info, sizeof(info));
+ list_for_each_entry(iter, &recv_list, list) {
+ if (iter->info.fsid == info.fsid &&
+ iter->info.number == info.number &&
+ iter->info.owner == info.owner) {
+ struct plock_xop *xop = (struct plock_xop *)iter;
+
+ list_del_init(&iter->list);
+ memcpy(&iter->info, &info, sizeof(info));
if (xop->callback)
do_callback = 1;
else
- op->done = 1;
- found = 1;
+ iter->done = 1;
+ op = iter;
break;
}
}
spin_unlock(&ops_lock);
- if (found) {
+ if (op) {
if (do_callback)
dlm_plock_callback(op);
else
diff --git a/fs/dlm/recover.c b/fs/dlm/recover.c
index 8928e99dfd47..15ad5c2c9dfc 100644
--- a/fs/dlm/recover.c
+++ b/fs/dlm/recover.c
@@ -732,10 +732,9 @@ void dlm_recovered_lock(struct dlm_rsb *r)
static void recover_lvb(struct dlm_rsb *r)
{
- struct dlm_lkb *lkb, *high_lkb = NULL;
+ struct dlm_lkb *lkb = NULL, *iter, *high_lkb = NULL;
uint32_t high_seq = 0;
int lock_lvb_exists = 0;
- int big_lock_exists = 0;
int lvblen = r->res_ls->ls_lvblen;
if (!rsb_flag(r, RSB_NEW_MASTER2) &&
@@ -751,37 +750,37 @@ static void recover_lvb(struct dlm_rsb *r)
/* we are the new master, so figure out if VALNOTVALID should
be set, and set the rsb lvb from the best lkb available. */
- list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
- if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
+ list_for_each_entry(iter, &r->res_grantqueue, lkb_statequeue) {
+ if (!(iter->lkb_exflags & DLM_LKF_VALBLK))
continue;
lock_lvb_exists = 1;
- if (lkb->lkb_grmode > DLM_LOCK_CR) {
- big_lock_exists = 1;
+ if (iter->lkb_grmode > DLM_LOCK_CR) {
+ lkb = iter;
goto setflag;
}
- if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
- high_lkb = lkb;
- high_seq = lkb->lkb_lvbseq;
+ if (((int)iter->lkb_lvbseq - (int)high_seq) >= 0) {
+ high_lkb = iter;
+ high_seq = iter->lkb_lvbseq;
}
}
- list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
- if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
+ list_for_each_entry(iter, &r->res_convertqueue, lkb_statequeue) {
+ if (!(iter->lkb_exflags & DLM_LKF_VALBLK))
continue;
lock_lvb_exists = 1;
- if (lkb->lkb_grmode > DLM_LOCK_CR) {
- big_lock_exists = 1;
+ if (iter->lkb_grmode > DLM_LOCK_CR) {
+ lkb = iter;
goto setflag;
}
- if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) {
- high_lkb = lkb;
- high_seq = lkb->lkb_lvbseq;
+ if (((int)iter->lkb_lvbseq - (int)high_seq) >= 0) {
+ high_lkb = iter;
+ high_seq = iter->lkb_lvbseq;
}
}
@@ -790,7 +789,7 @@ static void recover_lvb(struct dlm_rsb *r)
goto out;
/* lvb is invalidated if only NL/CR locks remain */
- if (!big_lock_exists)
+ if (!lkb)
rsb_set_flag(r, RSB_VALNOTVALID);
if (!r->res_lvbptr) {
@@ -799,7 +798,7 @@ static void recover_lvb(struct dlm_rsb *r)
goto out;
}
- if (big_lock_exists) {
+ if (lkb) {
r->res_lvbseq = lkb->lkb_lvbseq;
memcpy(r->res_lvbptr, lkb->lkb_lvbptr, lvblen);
} else if (high_lkb) {
--
2.25.1
^ permalink raw reply related [flat|nested] 2+ messages in thread