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authorDavid S. Miller2022-11-16 12:42:01 +0000
committerDavid S. Miller2022-11-16 12:42:01 +0000
commit68d268d089314b7c9c9754388a9a301175287b1a (patch)
tree0c745a13b644805bdb6f08f99251d486f1800911
parent8c55facecd7ade835287298ce325f930d888d8ec (diff)
parent4ebf802cf1c6a87fd14e7936728c99e18d7ba794 (diff)
Merge branch 'net-try_cmpxchg-conversions'
Eric Dumazet says: ==================== net: more try_cmpxchg() conversions Adopt try_cmpxchg() and friends in more places, as this is preferred nowadays. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--net/core/dev.c42
-rw-r--r--net/core/skbuff.c5
-rw-r--r--net/core/sock_diag.c12
-rw-r--r--net/ipv6/ip6_fib.c7
4 files changed, 26 insertions, 40 deletions
diff --git a/net/core/dev.c b/net/core/dev.c
index 117e830cabb0..fb943dad9651 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2073,13 +2073,10 @@ static DECLARE_WORK(netstamp_work, netstamp_clear);
void net_enable_timestamp(void)
{
#ifdef CONFIG_JUMP_LABEL
- int wanted;
+ int wanted = atomic_read(&netstamp_wanted);
- while (1) {
- wanted = atomic_read(&netstamp_wanted);
- if (wanted <= 0)
- break;
- if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted)
+ while (wanted > 0) {
+ if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1))
return;
}
atomic_inc(&netstamp_needed_deferred);
@@ -2093,13 +2090,10 @@ EXPORT_SYMBOL(net_enable_timestamp);
void net_disable_timestamp(void)
{
#ifdef CONFIG_JUMP_LABEL
- int wanted;
+ int wanted = atomic_read(&netstamp_wanted);
- while (1) {
- wanted = atomic_read(&netstamp_wanted);
- if (wanted <= 1)
- break;
- if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted)
+ while (wanted > 1) {
+ if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1))
return;
}
atomic_dec(&netstamp_needed_deferred);
@@ -5985,10 +5979,9 @@ EXPORT_SYMBOL(__napi_schedule);
*/
bool napi_schedule_prep(struct napi_struct *n)
{
- unsigned long val, new;
+ unsigned long new, val = READ_ONCE(n->state);
do {
- val = READ_ONCE(n->state);
if (unlikely(val & NAPIF_STATE_DISABLE))
return false;
new = val | NAPIF_STATE_SCHED;
@@ -6001,7 +5994,7 @@ bool napi_schedule_prep(struct napi_struct *n)
*/
new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED *
NAPIF_STATE_MISSED;
- } while (cmpxchg(&n->state, val, new) != val);
+ } while (!try_cmpxchg(&n->state, &val, new));
return !(val & NAPIF_STATE_SCHED);
}
@@ -6069,9 +6062,8 @@ bool napi_complete_done(struct napi_struct *n, int work_done)
local_irq_restore(flags);
}
+ val = READ_ONCE(n->state);
do {
- val = READ_ONCE(n->state);
-
WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED));
new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED |
@@ -6084,7 +6076,7 @@ bool napi_complete_done(struct napi_struct *n, int work_done)
*/
new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED *
NAPIF_STATE_SCHED;
- } while (cmpxchg(&n->state, val, new) != val);
+ } while (!try_cmpxchg(&n->state, &val, new));
if (unlikely(val & NAPIF_STATE_MISSED)) {
__napi_schedule(n);
@@ -6405,8 +6397,8 @@ void napi_disable(struct napi_struct *n)
might_sleep();
set_bit(NAPI_STATE_DISABLE, &n->state);
- for ( ; ; ) {
- val = READ_ONCE(n->state);
+ val = READ_ONCE(n->state);
+ do {
if (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) {
usleep_range(20, 200);
continue;
@@ -6414,10 +6406,7 @@ void napi_disable(struct napi_struct *n)
new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC;
new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL);
-
- if (cmpxchg(&n->state, val, new) == val)
- break;
- }
+ } while (!try_cmpxchg(&n->state, &val, new));
hrtimer_cancel(&n->timer);
@@ -6434,16 +6423,15 @@ EXPORT_SYMBOL(napi_disable);
*/
void napi_enable(struct napi_struct *n)
{
- unsigned long val, new;
+ unsigned long new, val = READ_ONCE(n->state);
do {
- val = READ_ONCE(n->state);
BUG_ON(!test_bit(NAPI_STATE_SCHED, &val));
new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC);
if (n->dev->threaded && n->thread)
new |= NAPIF_STATE_THREADED;
- } while (cmpxchg(&n->state, val, new) != val);
+ } while (!try_cmpxchg(&n->state, &val, new));
}
EXPORT_SYMBOL(napi_enable);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 90d085290d49..4bf95e36ed16 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1267,13 +1267,12 @@ int mm_account_pinned_pages(struct mmpin *mmp, size_t size)
max_pg = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
user = mmp->user ? : current_user();
+ old_pg = atomic_long_read(&user->locked_vm);
do {
- old_pg = atomic_long_read(&user->locked_vm);
new_pg = old_pg + num_pg;
if (new_pg > max_pg)
return -ENOBUFS;
- } while (atomic_long_cmpxchg(&user->locked_vm, old_pg, new_pg) !=
- old_pg);
+ } while (!atomic_long_try_cmpxchg(&user->locked_vm, &old_pg, new_pg));
if (!mmp->user) {
mmp->user = get_uid(user);
diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c
index f7cf74cdd3db..b11593cae5a0 100644
--- a/net/core/sock_diag.c
+++ b/net/core/sock_diag.c
@@ -25,14 +25,14 @@ DEFINE_COOKIE(sock_cookie);
u64 __sock_gen_cookie(struct sock *sk)
{
- while (1) {
- u64 res = atomic64_read(&sk->sk_cookie);
+ u64 res = atomic64_read(&sk->sk_cookie);
- if (res)
- return res;
- res = gen_cookie_next(&sock_cookie);
- atomic64_cmpxchg(&sk->sk_cookie, 0, res);
+ if (!res) {
+ u64 new = gen_cookie_next(&sock_cookie);
+
+ atomic64_try_cmpxchg(&sk->sk_cookie, &res, new);
}
+ return res;
}
int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie)
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 413f66781e50..2438da5ff6da 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -91,13 +91,12 @@ static void fib6_walker_unlink(struct net *net, struct fib6_walker *w)
static int fib6_new_sernum(struct net *net)
{
- int new, old;
+ int new, old = atomic_read(&net->ipv6.fib6_sernum);
do {
- old = atomic_read(&net->ipv6.fib6_sernum);
new = old < INT_MAX ? old + 1 : 1;
- } while (atomic_cmpxchg(&net->ipv6.fib6_sernum,
- old, new) != old);
+ } while (!atomic_try_cmpxchg(&net->ipv6.fib6_sernum, &old, new));
+
return new;
}