From 751a68b2e46fe11a42450cb55a16e8065eddec7e Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 7 May 2012 13:44:44 -0700 Subject: rcu: Rationalize ordering of torture_ops list Move the raw SRCU interfaces out of the middle of the normal SRCU interfaces. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutorture.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/rcutorture.c') diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index e66b34ab755..9850479f319 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -1908,8 +1908,8 @@ rcu_torture_init(void) static struct rcu_torture_ops *torture_ops[] = { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops, &rcu_bh_ops, &rcu_bh_sync_ops, &rcu_bh_expedited_ops, - &srcu_ops, &srcu_sync_ops, &srcu_raw_ops, - &srcu_raw_sync_ops, &srcu_expedited_ops, + &srcu_ops, &srcu_sync_ops, &srcu_expedited_ops, + &srcu_raw_ops, &srcu_raw_sync_ops, &sched_ops, &sched_sync_ops, &sched_expedited_ops, }; mutex_lock(&fullstop_mutex); -- cgit v1.2.3-70-g09d2 From e3f8d3788ed7cf55946030dc9b76e73edb111602 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 8 May 2012 10:21:50 -0700 Subject: rcu: Test srcu_barrier() from rcutorture test suite SRCU now has a call_srcu() and an srcu_barrier(), but rcutorture does not test them. This commit adds the machinery to allow rcutorture's existing tests for call_rcu() and rcu_barrier() to apply to the SRCU equivalents. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutorture.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'kernel/rcutorture.c') diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 9850479f319..7b6935e0cee 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -635,6 +635,17 @@ static void srcu_torture_synchronize(void) synchronize_srcu(&srcu_ctl); } +static void srcu_torture_call(struct rcu_head *head, + void (*func)(struct rcu_head *head)) +{ + call_srcu(&srcu_ctl, head, func); +} + +static void srcu_torture_barrier(void) +{ + srcu_barrier(&srcu_ctl); +} + static int srcu_torture_stats(char *page) { int cnt = 0; @@ -661,8 +672,8 @@ static struct rcu_torture_ops srcu_ops = { .completed = srcu_torture_completed, .deferred_free = srcu_torture_deferred_free, .sync = srcu_torture_synchronize, - .call = NULL, - .cb_barrier = NULL, + .call = srcu_torture_call, + .cb_barrier = srcu_torture_barrier, .stats = srcu_torture_stats, .name = "srcu" }; -- cgit v1.2.3-70-g09d2 From c6ebcbb60c8c68a88160fe54302e851700d1362c Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 28 May 2012 19:21:41 -0700 Subject: rcu: Fix bug in rcu_barrier() torture test The child threads in the rcu_torture_barrier_cbs() are improperly synchronized, which can cause the rcu_barrier() tests to hang. The failure mode is as follows: 1. CPU 0 running in rcu_torture_barrier() sets barrier_cbs_count to n_barrier_cbs. 2. CPU 1 running in rcu_torture_barrier_cbs() wakes up, posts its RCU callback, and atomically decrements barrier_cbs_count. Because barrier_cbs_count is not zero, it does not do the wake_up(). 3. CPU 2 running in rcu_torture_barrier_cbs() wakes up, but finds that barrier_cbs_count is not equal to n_barrier_cbs, and so returns to sleep. 4. The value of barrier_cbs_count therefore never reaches zero, which causes the test to hang. This commit therefore uses a phase variable to coordinate the test, preventing this scenario from occurring. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- kernel/rcutorture.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'kernel/rcutorture.c') diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 7b6935e0cee..f7fe73e59c9 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -206,6 +206,7 @@ static unsigned long boost_starttime; /* jiffies of next boost test start. */ DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ /* and boost task create/destroy. */ static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */ +static bool barrier_phase; /* Test phase. */ static atomic_t barrier_cbs_invoked; /* Barrier callbacks invoked. */ static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */ static DECLARE_WAIT_QUEUE_HEAD(barrier_wq); @@ -1642,6 +1643,7 @@ void rcu_torture_barrier_cbf(struct rcu_head *rcu) static int rcu_torture_barrier_cbs(void *arg) { long myid = (long)arg; + bool lastphase = 0; struct rcu_head rcu; init_rcu_head_on_stack(&rcu); @@ -1649,9 +1651,11 @@ static int rcu_torture_barrier_cbs(void *arg) set_user_nice(current, 19); do { wait_event(barrier_cbs_wq[myid], - atomic_read(&barrier_cbs_count) == n_barrier_cbs || + barrier_phase != lastphase || kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP); + lastphase = barrier_phase; + smp_mb(); /* ensure barrier_phase load before ->call(). */ if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP) break; cur_ops->call(&rcu, rcu_torture_barrier_cbf); @@ -1676,7 +1680,8 @@ static int rcu_torture_barrier(void *arg) do { atomic_set(&barrier_cbs_invoked, 0); atomic_set(&barrier_cbs_count, n_barrier_cbs); - /* wake_up() path contains the required barriers. */ + smp_mb(); /* Ensure barrier_phase after prior assignments. */ + barrier_phase = !barrier_phase; for (i = 0; i < n_barrier_cbs; i++) wake_up(&barrier_cbs_wq[i]); wait_event(barrier_wq, -- cgit v1.2.3-70-g09d2 From 143aa672f4fc643420c8325ad09c379ed33a27cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 24 May 2012 18:17:48 -0700 Subject: rcu: Fix diagnostic-printk typo in rcutorture The rcu_torture_barrier() function has a copy-and-paste typo in the string passed to rcutorture_shutdown_absorb(), which this commit fixes. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutorture.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/rcutorture.c') diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index f7fe73e59c9..045a3dc233e 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -1700,7 +1700,7 @@ static int rcu_torture_barrier(void *arg) schedule_timeout_interruptible(HZ / 10); } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); VERBOSE_PRINTK_STRING("rcu_torture_barrier task stopping"); - rcutorture_shutdown_absorb("rcu_torture_barrier_cbs"); + rcutorture_shutdown_absorb("rcu_torture_barrier"); while (!kthread_should_stop()) schedule_timeout_interruptible(1); return 0; -- cgit v1.2.3-70-g09d2 From 72472a02a9c4507ef54d03d71bb253c26015f52c Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 29 May 2012 17:50:51 -0700 Subject: rcu: Make rcutorture fakewriters invoke rcu_barrier() The current rcutorture rcu_barrier() testing never intentionally runs more than one instance of rcu_barrier() at a given time. This fails to test the the shiny new concurrency features of rcu_barrier(). This commit therefore modifies the rcutorture fakewriter kthread to randomly invoke rcu_barrier() rather than the usual synchronize_rcu(). Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- kernel/rcutorture.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'kernel/rcutorture.c') diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 045a3dc233e..c279ee92094 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -1025,7 +1025,11 @@ rcu_torture_fakewriter(void *arg) do { schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); udelay(rcu_random(&rand) & 0x3ff); - cur_ops->sync(); + if (cur_ops->cb_barrier != NULL && + rcu_random(&rand) % (nfakewriters * 8) == 0) + cur_ops->cb_barrier(); + else + cur_ops->sync(); rcu_stutter_wait("rcu_torture_fakewriter"); } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); -- cgit v1.2.3-70-g09d2 From c701d5d9b384ff03ceb232ef21236364d784a411 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 28 Jun 2012 08:08:25 -0700 Subject: rcu: Fix code-style issues involving "else" The Linux kernel coding style says that single-statement blocks should omit curly braces unless the other leg of the "if" statement has multiple statements, in which case the curly braces should be included. This commit fixes RCU's violations of this rule. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutiny_plugin.h | 7 ++++--- kernel/rcutorture.c | 3 ++- kernel/rcutree.c | 7 ++++--- kernel/rcutree_plugin.h | 14 ++++++++------ 4 files changed, 18 insertions(+), 13 deletions(-) (limited to 'kernel/rcutorture.c') diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h index 116725b5edf..918fd1e8509 100644 --- a/kernel/rcutiny_plugin.h +++ b/kernel/rcutiny_plugin.h @@ -350,8 +350,9 @@ static int rcu_initiate_boost(void) rcu_preempt_ctrlblk.boost_tasks = rcu_preempt_ctrlblk.gp_tasks; invoke_rcu_callbacks(); - } else + } else { RCU_TRACE(rcu_initiate_boost_trace()); + } return 1; } @@ -778,9 +779,9 @@ void synchronize_rcu_expedited(void) rpcp->exp_tasks = NULL; /* Wait for tail of ->blkd_tasks list to drain. */ - if (!rcu_preempted_readers_exp()) + if (!rcu_preempted_readers_exp()) { local_irq_restore(flags); - else { + } else { rcu_initiate_boost(); local_irq_restore(flags); wait_event(sync_rcu_preempt_exp_wq, diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index c279ee92094..155fb129b64 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -408,8 +408,9 @@ rcu_torture_cb(struct rcu_head *p) if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { rp->rtort_mbtest = 0; rcu_torture_free(rp); - } else + } else { cur_ops->deferred_free(rp); + } } static int rcu_no_completed(void) diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 117218a4372..f280e542e3e 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -892,8 +892,9 @@ static void __note_new_gpnum(struct rcu_state *rsp, struct rcu_node *rnp, struct if (rnp->qsmask & rdp->grpmask) { rdp->qs_pending = 1; rdp->passed_quiesce = 0; - } else + } else { rdp->qs_pending = 0; + } zero_cpu_stall_ticks(rdp); } } @@ -2130,9 +2131,9 @@ void synchronize_sched_expedited(void) put_online_cpus(); /* No joy, try again later. Or just synchronize_sched(). */ - if (trycount++ < 10) + if (trycount++ < 10) { udelay(trycount * num_online_cpus()); - else { + } else { synchronize_sched(); return; } diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index a9194d5606c..7f3244c0df0 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -390,8 +390,9 @@ void rcu_read_unlock_special(struct task_struct *t) rnp->grphi, !!rnp->gp_tasks); rcu_report_unblock_qs_rnp(rnp, flags); - } else + } else { raw_spin_unlock_irqrestore(&rnp->lock, flags); + } #ifdef CONFIG_RCU_BOOST /* Unboost if we were boosted. */ @@ -757,9 +758,9 @@ sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp) int must_wait = 0; raw_spin_lock_irqsave(&rnp->lock, flags); - if (list_empty(&rnp->blkd_tasks)) + if (list_empty(&rnp->blkd_tasks)) { raw_spin_unlock_irqrestore(&rnp->lock, flags); - else { + } else { rnp->exp_tasks = rnp->blkd_tasks.next; rcu_initiate_boost(rnp, flags); /* releases rnp->lock */ must_wait = 1; @@ -803,9 +804,9 @@ void synchronize_rcu_expedited(void) * expedited grace period for us, just leave. */ while (!mutex_trylock(&sync_rcu_preempt_exp_mutex)) { - if (trycount++ < 10) + if (trycount++ < 10) { udelay(trycount * num_online_cpus()); - else { + } else { synchronize_rcu(); return; } @@ -2093,8 +2094,9 @@ static void rcu_prepare_for_idle(int cpu) if (rcu_cpu_has_callbacks(cpu)) { trace_rcu_prep_idle("More callbacks"); invoke_rcu_core(); - } else + } else { trace_rcu_prep_idle("Callbacks drained"); + } } /* -- cgit v1.2.3-70-g09d2 From 5cf05ad758c30d17ff23c2be346b5de982bc2121 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 17 May 2012 15:12:45 -0700 Subject: rcu: Fix broken strings in RCU's source code. Although the C language allows you to break strings across lines, doing this makes it hard for people to find the Linux kernel code corresponding to a given console message. This commit therefore fixes broken strings throughout RCU's source code. Suggested-by: Josh Triplett Suggested-by: Ingo Molnar Signed-off-by: Paul E. McKenney --- include/linux/rcupdate.h | 3 +-- kernel/rcutorture.c | 33 ++++++++++++++------------------- kernel/rcutree_trace.c | 25 ++++++++++++------------- lib/list_debug.c | 6 ++---- 4 files changed, 29 insertions(+), 38 deletions(-) (limited to 'kernel/rcutorture.c') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index c2c0d86dd3a..115ead2b515 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -427,8 +427,7 @@ extern int rcu_my_thread_group_empty(void); static inline void rcu_preempt_sleep_check(void) { rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), - "Illegal context switch in RCU read-side " - "critical section"); + "Illegal context switch in RCU read-side critical section"); } #else /* #ifdef CONFIG_PROVE_RCU */ static inline void rcu_preempt_sleep_check(void) diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 155fb129b64..25b15033c61 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -49,8 +49,7 @@ #include MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Paul E. McKenney and " - "Josh Triplett "); +MODULE_AUTHOR("Paul E. McKenney and Josh Triplett "); static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ static int nfakewriters = 4; /* # fake writer threads */ @@ -1200,27 +1199,27 @@ rcu_torture_printk(char *page) } cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); cnt += sprintf(&page[cnt], - "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d " - "rtmbe: %d rtbke: %ld rtbre: %ld " - "rtbf: %ld rtb: %ld nt: %ld " - "onoff: %ld/%ld:%ld/%ld " - "barrier: %ld/%ld:%ld", + "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", rcu_torture_current, rcu_torture_current_version, list_empty(&rcu_torture_freelist), atomic_read(&n_rcu_torture_alloc), atomic_read(&n_rcu_torture_alloc_fail), - atomic_read(&n_rcu_torture_free), + atomic_read(&n_rcu_torture_free)); + cnt += sprintf(&page[cnt], "rtmbe: %d rtbke: %ld rtbre: %ld ", atomic_read(&n_rcu_torture_mberror), n_rcu_torture_boost_ktrerror, - n_rcu_torture_boost_rterror, + n_rcu_torture_boost_rterror); + cnt += sprintf(&page[cnt], "rtbf: %ld rtb: %ld nt: %ld ", n_rcu_torture_boost_failure, n_rcu_torture_boosts, - n_rcu_torture_timers, + n_rcu_torture_timers); + cnt += sprintf(&page[cnt], "onoff: %ld/%ld:%ld/%ld ", n_online_successes, n_online_attempts, n_offline_successes, - n_offline_attempts, + n_offline_attempts); + cnt += sprintf(&page[cnt], "barrier: %ld/%ld:%ld", n_barrier_successes, n_barrier_attempts, n_rcu_torture_barrier_error); @@ -1462,8 +1461,7 @@ rcu_torture_shutdown(void *arg) delta = shutdown_time - jiffies_snap; if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG - "rcu_torture_shutdown task: %lu " - "jiffies remaining\n", + "rcu_torture_shutdown task: %lu jiffies remaining\n", torture_type, delta); schedule_timeout_interruptible(delta); jiffies_snap = ACCESS_ONCE(jiffies); @@ -1515,8 +1513,7 @@ rcu_torture_onoff(void *arg) if (cpu_down(cpu) == 0) { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG - "rcu_torture_onoff task: " - "offlined %d\n", + "rcu_torture_onoff task: offlined %d\n", torture_type, cpu); n_offline_successes++; } @@ -1529,8 +1526,7 @@ rcu_torture_onoff(void *arg) if (cpu_up(cpu) == 0) { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG - "rcu_torture_onoff task: " - "onlined %d\n", + "rcu_torture_onoff task: onlined %d\n", torture_type, cpu); n_online_successes++; } @@ -1952,8 +1948,7 @@ rcu_torture_init(void) return -EINVAL; } if (cur_ops->fqs == NULL && fqs_duration != 0) { - printk(KERN_ALERT "rcu-torture: ->fqs NULL and non-zero " - "fqs_duration, fqs disabled.\n"); + printk(KERN_ALERT "rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); fqs_duration = 0; } if (cur_ops->init) diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c index a16ddbd6fdc..abffb486e94 100644 --- a/kernel/rcutree_trace.c +++ b/kernel/rcutree_trace.c @@ -218,8 +218,7 @@ static const struct file_operations rcudata_csv_fops = { static void print_one_rcu_node_boost(struct seq_file *m, struct rcu_node *rnp) { - seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu " - "j=%04x bt=%04x\n", + seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu ", rnp->grplo, rnp->grphi, "T."[list_empty(&rnp->blkd_tasks)], "N."[!rnp->gp_tasks], @@ -227,11 +226,11 @@ static void print_one_rcu_node_boost(struct seq_file *m, struct rcu_node *rnp) "B."[!rnp->boost_tasks], convert_kthread_status(rnp->boost_kthread_status), rnp->n_tasks_boosted, rnp->n_exp_boosts, - rnp->n_normal_boosts, + rnp->n_normal_boosts); + seq_printf(m, "j=%04x bt=%04x\n", (int)(jiffies & 0xffff), (int)(rnp->boost_time & 0xffff)); - seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n", - " balk", + seq_printf(m, " balk: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n", rnp->n_balk_blkd_tasks, rnp->n_balk_exp_gp_tasks, rnp->n_balk_boost_tasks, @@ -287,11 +286,11 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp) struct rcu_node *rnp; gpnum = rsp->gpnum; - seq_printf(m, "%s: c=%lu g=%lu s=%d jfq=%ld j=%x " - "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n", + seq_printf(m, "%s: c=%lu g=%lu s=%d jfq=%ld j=%x ", rsp->name, rsp->completed, gpnum, rsp->fqs_state, (long)(rsp->jiffies_force_qs - jiffies), - (int)(jiffies & 0xffff), + (int)(jiffies & 0xffff)); + seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n", rsp->n_force_qs, rsp->n_force_qs_ngp, rsp->n_force_qs - rsp->n_force_qs_ngp, rsp->n_force_qs_lh, rsp->qlen_lazy, rsp->qlen); @@ -378,16 +377,16 @@ static const struct file_operations rcugp_fops = { static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp) { - seq_printf(m, "%3d%cnp=%ld " - "qsp=%ld rpq=%ld cbr=%ld cng=%ld " - "gpc=%ld gps=%ld nf=%ld nn=%ld\n", + seq_printf(m, "%3d%cnp=%ld ", rdp->cpu, cpu_is_offline(rdp->cpu) ? '!' : ' ', - rdp->n_rcu_pending, + rdp->n_rcu_pending); + seq_printf(m, "qsp=%ld rpq=%ld cbr=%ld cng=%ld ", rdp->n_rp_qs_pending, rdp->n_rp_report_qs, rdp->n_rp_cb_ready, - rdp->n_rp_cpu_needs_gp, + rdp->n_rp_cpu_needs_gp); + seq_printf(m, "gpc=%ld gps=%ld nf=%ld nn=%ld\n", rdp->n_rp_gp_completed, rdp->n_rp_gp_started, rdp->n_rp_need_fqs, diff --git a/lib/list_debug.c b/lib/list_debug.c index 23a5e031cd8..c24c2f7e296 100644 --- a/lib/list_debug.c +++ b/lib/list_debug.c @@ -87,12 +87,10 @@ void __list_add_rcu(struct list_head *new, struct list_head *prev, struct list_head *next) { WARN(next->prev != prev, - "list_add_rcu corruption. next->prev should be " - "prev (%p), but was %p. (next=%p).\n", + "list_add_rcu corruption. next->prev should be prev (%p), but was %p. (next=%p).\n", prev, next->prev, next); WARN(prev->next != next, - "list_add_rcu corruption. prev->next should be " - "next (%p), but was %p. (prev=%p).\n", + "list_add_rcu corruption. prev->next should be next (%p), but was %p. (prev=%p).\n", next, prev->next, prev); new->next = next; new->prev = prev; -- cgit v1.2.3-70-g09d2