From: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
To: "Paul E . McKenney" <paulmck@kernel.org>
Cc: RCU <rcu@vger.kernel.org>,
Neeraj upadhyay <Neeraj.Upadhyay@amd.com>,
Boqun Feng <boqun.feng@gmail.com>,
Hillf Danton <hdanton@sina.com>,
Joel Fernandes <joel@joelfernandes.org>,
LKML <linux-kernel@vger.kernel.org>,
Uladzislau Rezki <urezki@gmail.com>,
Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>,
Frederic Weisbecker <frederic@kernel.org>,
Zqiang <qiang.zhang1211@gmail.com>
Subject: [PATCH 43/48] rcutorture: Make rcutorture support print rcu-tasks gp state
Date: Tue, 7 May 2024 11:35:25 +0200 [thread overview]
Message-ID: <20240507093530.3043-44-urezki@gmail.com> (raw)
In-Reply-To: <20240507093530.3043-1-urezki@gmail.com>
From: Zqiang <qiang.zhang1211@gmail.com>
This commit make rcu-tasks related rcutorture test support rcu-tasks
gp state printing when the writer stall occurs or the at the end of
rcutorture test, and generate rcu_ops->get_gp_data() operation to
simplify the acquisition of gp state for different types of rcutorture
tests.
Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
---
kernel/rcu/rcu.h | 20 ++++++++++----------
kernel/rcu/rcutorture.c | 26 ++++++++++++++++++--------
kernel/rcu/srcutree.c | 5 +----
kernel/rcu/tasks.h | 21 +++++++++++++++++++++
kernel/rcu/tree.c | 13 +++----------
5 files changed, 53 insertions(+), 32 deletions(-)
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index 86fce206560e..38238e595a61 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -522,12 +522,18 @@ static inline void show_rcu_tasks_gp_kthreads(void) {}
#ifdef CONFIG_TASKS_RCU
struct task_struct *get_rcu_tasks_gp_kthread(void);
+void rcu_tasks_get_gp_data(int *flags, unsigned long *gp_seq);
#endif // # ifdef CONFIG_TASKS_RCU
#ifdef CONFIG_TASKS_RUDE_RCU
struct task_struct *get_rcu_tasks_rude_gp_kthread(void);
+void rcu_tasks_rude_get_gp_data(int *flags, unsigned long *gp_seq);
#endif // # ifdef CONFIG_TASKS_RUDE_RCU
+#ifdef CONFIG_TASKS_TRACE_RCU
+void rcu_tasks_trace_get_gp_data(int *flags, unsigned long *gp_seq);
+#endif
+
#ifdef CONFIG_TASKS_RCU_GENERIC
void tasks_cblist_init_generic(void);
#else /* #ifdef CONFIG_TASKS_RCU_GENERIC */
@@ -557,8 +563,7 @@ static inline void rcu_set_jiffies_lazy_flush(unsigned long j) { }
#endif
#if defined(CONFIG_TREE_RCU)
-void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags,
- unsigned long *gp_seq);
+void rcutorture_get_gp_data(int *flags, unsigned long *gp_seq);
void do_trace_rcu_torture_read(const char *rcutorturename,
struct rcu_head *rhp,
unsigned long secs,
@@ -566,8 +571,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename,
unsigned long c);
void rcu_gp_set_torture_wait(int duration);
#else
-static inline void rcutorture_get_gp_data(enum rcutorture_type test_type,
- int *flags, unsigned long *gp_seq)
+static inline void rcutorture_get_gp_data(int *flags, unsigned long *gp_seq)
{
*flags = 0;
*gp_seq = 0;
@@ -587,20 +591,16 @@ static inline void rcu_gp_set_torture_wait(int duration) { }
#ifdef CONFIG_TINY_SRCU
-static inline void srcutorture_get_gp_data(enum rcutorture_type test_type,
- struct srcu_struct *sp, int *flags,
+static inline void srcutorture_get_gp_data(struct srcu_struct *sp, int *flags,
unsigned long *gp_seq)
{
- if (test_type != SRCU_FLAVOR)
- return;
*flags = 0;
*gp_seq = sp->srcu_idx;
}
#elif defined(CONFIG_TREE_SRCU)
-void srcutorture_get_gp_data(enum rcutorture_type test_type,
- struct srcu_struct *sp, int *flags,
+void srcutorture_get_gp_data(struct srcu_struct *sp, int *flags,
unsigned long *gp_seq);
#endif
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 2f43d31fb7a5..85ff8a32f75a 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -381,6 +381,7 @@ struct rcu_torture_ops {
void (*gp_kthread_dbg)(void);
bool (*check_boost_failed)(unsigned long gp_state, int *cpup);
int (*stall_dur)(void);
+ void (*get_gp_data)(int *flags, unsigned long *gp_seq);
long cbflood_max;
int irq_capable;
int can_boost;
@@ -569,6 +570,7 @@ static struct rcu_torture_ops rcu_ops = {
.gp_kthread_dbg = show_rcu_gp_kthreads,
.check_boost_failed = rcu_check_boost_fail,
.stall_dur = rcu_jiffies_till_stall_check,
+ .get_gp_data = rcutorture_get_gp_data,
.irq_capable = 1,
.can_boost = IS_ENABLED(CONFIG_RCU_BOOST),
.extendables = RCUTORTURE_MAX_EXTEND,
@@ -628,6 +630,11 @@ static struct srcu_struct srcu_ctld;
static struct srcu_struct *srcu_ctlp = &srcu_ctl;
static struct rcu_torture_ops srcud_ops;
+static void srcu_get_gp_data(int *flags, unsigned long *gp_seq)
+{
+ srcutorture_get_gp_data(srcu_ctlp, flags, gp_seq);
+}
+
static int srcu_torture_read_lock(void)
{
if (cur_ops == &srcud_ops)
@@ -736,6 +743,7 @@ static struct rcu_torture_ops srcu_ops = {
.call = srcu_torture_call,
.cb_barrier = srcu_torture_barrier,
.stats = srcu_torture_stats,
+ .get_gp_data = srcu_get_gp_data,
.cbflood_max = 50000,
.irq_capable = 1,
.no_pi_lock = IS_ENABLED(CONFIG_TINY_SRCU),
@@ -774,6 +782,7 @@ static struct rcu_torture_ops srcud_ops = {
.call = srcu_torture_call,
.cb_barrier = srcu_torture_barrier,
.stats = srcu_torture_stats,
+ .get_gp_data = srcu_get_gp_data,
.cbflood_max = 50000,
.irq_capable = 1,
.no_pi_lock = IS_ENABLED(CONFIG_TINY_SRCU),
@@ -882,6 +891,7 @@ static struct rcu_torture_ops tasks_ops = {
.call = call_rcu_tasks,
.cb_barrier = rcu_barrier_tasks,
.gp_kthread_dbg = show_rcu_tasks_classic_gp_kthread,
+ .get_gp_data = rcu_tasks_get_gp_data,
.fqs = NULL,
.stats = NULL,
.irq_capable = 1,
@@ -922,6 +932,7 @@ static struct rcu_torture_ops tasks_rude_ops = {
.call = call_rcu_tasks_rude,
.cb_barrier = rcu_barrier_tasks_rude,
.gp_kthread_dbg = show_rcu_tasks_rude_gp_kthread,
+ .get_gp_data = rcu_tasks_rude_get_gp_data,
.cbflood_max = 50000,
.fqs = NULL,
.stats = NULL,
@@ -974,6 +985,7 @@ static struct rcu_torture_ops tasks_tracing_ops = {
.call = call_rcu_tasks_trace,
.cb_barrier = rcu_barrier_tasks_trace,
.gp_kthread_dbg = show_rcu_tasks_trace_gp_kthread,
+ .get_gp_data = rcu_tasks_trace_get_gp_data,
.cbflood_max = 50000,
.fqs = NULL,
.stats = NULL,
@@ -2264,10 +2276,8 @@ rcu_torture_stats_print(void)
int __maybe_unused flags = 0;
unsigned long __maybe_unused gp_seq = 0;
- rcutorture_get_gp_data(cur_ops->ttype,
- &flags, &gp_seq);
- srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp,
- &flags, &gp_seq);
+ if (cur_ops->get_gp_data)
+ cur_ops->get_gp_data(&flags, &gp_seq);
wtp = READ_ONCE(writer_task);
pr_alert("??? Writer stall state %s(%d) g%lu f%#x ->state %#x cpu %d\n",
rcu_torture_writer_state_getname(),
@@ -3390,8 +3400,8 @@ rcu_torture_cleanup(void)
fakewriter_tasks = NULL;
}
- rcutorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq);
- srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, &flags, &gp_seq);
+ if (cur_ops->get_gp_data)
+ cur_ops->get_gp_data(&flags, &gp_seq);
pr_alert("%s: End-test grace-period state: g%ld f%#x total-gps=%ld\n",
cur_ops->name, (long)gp_seq, flags,
rcutorture_seq_diff(gp_seq, start_gp_seq));
@@ -3762,8 +3772,8 @@ rcu_torture_init(void)
nrealreaders = 1;
}
rcu_torture_print_module_parms(cur_ops, "Start of test");
- rcutorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq);
- srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, &flags, &gp_seq);
+ if (cur_ops->get_gp_data)
+ cur_ops->get_gp_data(&flags, &gp_seq);
start_gp_seq = gp_seq;
pr_alert("%s: Start-test grace-period state: g%ld f%#x\n",
cur_ops->name, (long)gp_seq, flags);
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index e4d673fc30f4..bc4b58b0204e 100644
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -1826,12 +1826,9 @@ static void process_srcu(struct work_struct *work)
srcu_reschedule(ssp, curdelay);
}
-void srcutorture_get_gp_data(enum rcutorture_type test_type,
- struct srcu_struct *ssp, int *flags,
+void srcutorture_get_gp_data(struct srcu_struct *ssp, int *flags,
unsigned long *gp_seq)
{
- if (test_type != SRCU_FLAVOR)
- return;
*flags = 0;
*gp_seq = rcu_seq_current(&ssp->srcu_sup->srcu_gp_seq);
}
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 147b5945d67a..a1af7dadc0f7 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -1178,6 +1178,13 @@ struct task_struct *get_rcu_tasks_gp_kthread(void)
}
EXPORT_SYMBOL_GPL(get_rcu_tasks_gp_kthread);
+void rcu_tasks_get_gp_data(int *flags, unsigned long *gp_seq)
+{
+ *flags = 0;
+ *gp_seq = rcu_seq_current(&rcu_tasks.tasks_gp_seq);
+}
+EXPORT_SYMBOL_GPL(rcu_tasks_get_gp_data);
+
/*
* Protect against tasklist scan blind spot while the task is exiting and
* may be removed from the tasklist. Do this by adding the task to yet
@@ -1358,6 +1365,13 @@ struct task_struct *get_rcu_tasks_rude_gp_kthread(void)
}
EXPORT_SYMBOL_GPL(get_rcu_tasks_rude_gp_kthread);
+void rcu_tasks_rude_get_gp_data(int *flags, unsigned long *gp_seq)
+{
+ *flags = 0;
+ *gp_seq = rcu_seq_current(&rcu_tasks_rude.tasks_gp_seq);
+}
+EXPORT_SYMBOL_GPL(rcu_tasks_rude_get_gp_data);
+
#endif /* #ifdef CONFIG_TASKS_RUDE_RCU */
////////////////////////////////////////////////////////////////////////
@@ -2010,6 +2024,13 @@ struct task_struct *get_rcu_tasks_trace_gp_kthread(void)
}
EXPORT_SYMBOL_GPL(get_rcu_tasks_trace_gp_kthread);
+void rcu_tasks_trace_get_gp_data(int *flags, unsigned long *gp_seq)
+{
+ *flags = 0;
+ *gp_seq = rcu_seq_current(&rcu_tasks_trace.tasks_gp_seq);
+}
+EXPORT_SYMBOL_GPL(rcu_tasks_trace_get_gp_data);
+
#else /* #ifdef CONFIG_TASKS_TRACE_RCU */
static void exit_tasks_rcu_finish_trace(struct task_struct *t) { }
#endif /* #else #ifdef CONFIG_TASKS_TRACE_RCU */
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index d9642dd06c25..60e79ed73700 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -508,17 +508,10 @@ static struct rcu_node *rcu_get_root(void)
/*
* Send along grace-period-related data for rcutorture diagnostics.
*/
-void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags,
- unsigned long *gp_seq)
+void rcutorture_get_gp_data(int *flags, unsigned long *gp_seq)
{
- switch (test_type) {
- case RCU_FLAVOR:
- *flags = READ_ONCE(rcu_state.gp_flags);
- *gp_seq = rcu_seq_current(&rcu_state.gp_seq);
- break;
- default:
- break;
- }
+ *flags = READ_ONCE(rcu_state.gp_flags);
+ *gp_seq = rcu_seq_current(&rcu_state.gp_seq);
}
EXPORT_SYMBOL_GPL(rcutorture_get_gp_data);
--
2.39.2
next prev parent reply other threads:[~2024-05-07 9:36 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-07 9:34 [PATCH 00/48] RCU changes for v6.10 Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 01/48] scftorture: Increase memory provided to guest OS Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 02/48] rcutorture: Disable tracing to permit Tasks Rude RCU testing Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 03/48] rcu: Add lockdep checks and kernel-doc header to rcu_softirq_qs() Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 04/48] rcutorture: Enable RCU priority boosting for TREE09 Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 05/48] rcutorture: Dump # online CPUs on insufficient cb-flood laundering Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 06/48] rcutorture: Dump GP kthread state " Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 07/48] rcutorture: ASSERT_EXCLUSIVE_WRITER() for ->rtort_pipe_count updates Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 08/48] rcu-tasks: Make Tasks RCU wait idly for grace-period delays Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 09/48] doc: Remove references to arrayRCU.rst Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 10/48] MAINTAINERS: Update Neeraj's email address Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 11/48] bpf: Select new NEED_TASKS_RCU Kconfig option Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 12/48] arch: " Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 13/48] rcu: Add data structures for synchronize_rcu() Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 14/48] tracing: Select new NEED_TASKS_RCU Kconfig option Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 15/48] bpf: Choose RCU Tasks based on TASKS_RCU rather than PREEMPTION Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 16/48] ftrace: " Uladzislau Rezki (Sony)
2024-05-07 9:34 ` [PATCH 17/48] rcu: Update lockdep while in RCU read-side critical section Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 18/48] rcu: Make TINY_RCU depend on !PREEMPT_RCU rather than !PREEMPTION Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 19/48] srcu: Make Tiny SRCU explicitly disable preemption Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 20/48] rcu: Create NEED_TASKS_RCU to factor out enablement logic Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 21/48] rcu: Remove redundant BH disabling in TINY_RCU Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 22/48] rcu: Make Tiny RCU explicitly disable preemption Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 23/48] rcu: Remove redundant READ_ONCE() of rcu_state.gp_flags in tree.c Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 24/48] rcu: Bring diagnostic read of rcu_state.gp_flags into alignment Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 25/48] rcu: Mark writes to rcu_sync ->gp_count field Uladzislau Rezki (Sony)
2024-05-07 14:54 ` Oleg Nesterov
2024-05-07 17:44 ` Paul E. McKenney
2024-05-09 15:13 ` Oleg Nesterov
2024-05-10 3:59 ` Paul E. McKenney
2024-05-10 11:31 ` Oleg Nesterov
2024-05-10 14:00 ` Alan Huang
2024-05-10 14:04 ` Paul E. McKenney
2024-05-12 10:53 ` Oleg Nesterov
2024-05-12 14:57 ` Paul E. McKenney
2024-05-10 13:18 ` Oleg Nesterov
2024-05-10 13:50 ` Oleg Nesterov
2024-05-10 14:11 ` Paul E. McKenney
2024-05-12 10:41 ` Oleg Nesterov
2024-05-13 14:13 ` Marco Elver
2024-05-14 16:54 ` Paul E. McKenney
2024-05-10 13:58 ` Paul E. McKenney
2024-05-12 11:19 ` [PATCH] rcu/sync: don't read rcu_sync->gp_count lockless Oleg Nesterov
2024-05-12 15:10 ` Paul E. McKenney
2024-05-12 16:55 ` Oleg Nesterov
2024-05-12 17:11 ` Paul E. McKenney
2024-05-12 18:06 ` Oleg Nesterov
2024-05-07 9:35 ` [PATCH 26/48] rcu: Mark loads from rcu_state.n_online_cpus Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 27/48] rcu: Make hotplug operations track GP state, not flags Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 28/48] rcu: Inform KCSAN of one-byte cmpxchg() in rcu_trc_cmpxchg_need_qs() Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 29/48] rcu: Remove redundant CONFIG_PROVE_RCU #if condition Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 30/48] rcu-tasks: Replace exit_tasks_rcu_start() initialization with WARN_ON_ONCE() Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 31/48] rcu-tasks: Fix the comments for tasks_rcu_exit_srcu_stall_timer Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 32/48] rcu-tasks: Fix show_rcu_tasks_trace_gp_kthread buffer overflow Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 33/48] rcu: Mollify sparse with RCU guard Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 34/48] rcu: Fix buffer overflow in print_cpu_stall_info() Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 35/48] rcu: Reduce synchronize_rcu() latency Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 36/48] rcu: Add a trace event for synchronize_rcu_normal() Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 37/48] rcu: Support direct wake-up of synchronize_rcu() users Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 38/48] rcu: Allocate WQ with WQ_MEM_RECLAIM bit set Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 39/48] rcutorture: Remove extraneous rcu_torture_pipe_update_one() READ_ONCE() Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 40/48] rcutorture: Fix rcu_torture_one_read() pipe_count overflow comment Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 41/48] rcutorture: Re-use value stored to ->rtort_pipe_count instead of re-reading Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 42/48] rcutorture: Use the gp_kthread_dbg operation specified by cur_ops Uladzislau Rezki (Sony)
2024-05-07 9:35 ` Uladzislau Rezki (Sony) [this message]
2024-05-07 9:35 ` [PATCH 44/48] rcutorture: Removing redundant function pointer initialization Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 45/48] rcutorture: Make stall-tasks directly exit when rcutorture tests end Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 46/48] rcutorture: Fix invalid context warning when enable srcu barrier testing Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 47/48] torture: Scale --do-kvfree test time Uladzislau Rezki (Sony)
2024-05-07 9:35 ` [PATCH 48/48] rcutorture: Use rcu_gp_slow_register/unregister() only for rcutype test Uladzislau Rezki (Sony)
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