openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

rcu: Add expedited-grace-period event tracing 

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit is contained in:
Paul E. McKenney 2016-01-28 20:49:49 -08:00
parent bea2de44ae
commit 4f41530245
2 changed files with 16 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
kernel/rcu/tree.c
View File

@ -3584,17 +3584,18 @@ static bool sync_exp_work_done(struct rcu_state *rsp, struct rcu_node *rnp,
atomic_long_t *stat, unsigned long s)
{
if (rcu_exp_gp_seq_done(rsp, s)) {
trace_rcu_exp_grace_period(rsp->name, s, TPS("done"));
if (rnp) {
mutex_unlock(&rnp->exp_funnel_mutex);
trace_rcu_exp_funnel_lock(rsp->name, rnp->level,
rnp->grplo, rnp->grphi,
TPS("rel"));
mutex_unlock(&rnp->exp_funnel_mutex);
} else if (rdp) {
mutex_unlock(&rdp->exp_funnel_mutex);
trace_rcu_exp_funnel_lock(rsp->name,
rdp->mynode->level + 1,
rdp->cpu, rdp->cpu,
TPS("rel"));
mutex_unlock(&rdp->exp_funnel_mutex);
}
/* Ensure test happens before caller kfree(). */
smp_mb__before_atomic(); /* ^^^ */
@ -3624,12 +3625,12 @@ static struct rcu_node *exp_funnel_lock(struct rcu_state *rsp, unsigned long s)
rnp0 = rcu_get_root(rsp);
if (!mutex_is_locked(&rnp0->exp_funnel_mutex)) {
if (mutex_trylock(&rnp0->exp_funnel_mutex)) {
if (sync_exp_work_done(rsp, rnp0, NULL,
&rdp->expedited_workdone0, s))
return NULL;
trace_rcu_exp_funnel_lock(rsp->name, rnp0->level,
rnp0->grplo, rnp0->grphi,
TPS("acq"));
if (sync_exp_work_done(rsp, rnp0, NULL,
&rdp->expedited_workdone0, s))
return NULL;
return rnp0;
}
}
@ -3656,16 +3657,16 @@ static struct rcu_node *exp_funnel_lock(struct rcu_state *rsp, unsigned long s)
trace_rcu_exp_funnel_lock(rsp->name, rnp0->level,
rnp0->grplo, rnp0->grphi, TPS("acq"));
if (rnp1) {
mutex_unlock(&rnp1->exp_funnel_mutex);
trace_rcu_exp_funnel_lock(rsp->name, rnp1->level,
rnp1->grplo, rnp1->grphi,
TPS("rel"));
mutex_unlock(&rnp1->exp_funnel_mutex);
} else {
mutex_unlock(&rdp->exp_funnel_mutex);
trace_rcu_exp_funnel_lock(rsp->name,
rdp->mynode->level + 1,
rdp->cpu, rdp->cpu,
TPS("rel"));
mutex_unlock(&rdp->exp_funnel_mutex);
}
rnp1 = rnp0;
}
@ -3895,16 +3896,21 @@ void synchronize_sched_expedited(void)
/* Take a snapshot of the sequence number. */
s = rcu_exp_gp_seq_snap(rsp);
trace_rcu_exp_grace_period(rsp->name, s, TPS("snap"));
rnp = exp_funnel_lock(rsp, s);
if (rnp == NULL)
return; /* Someone else did our work for us. */
rcu_exp_gp_seq_start(rsp);
trace_rcu_exp_grace_period(rsp->name, s, TPS("start"));
sync_rcu_exp_select_cpus(rsp, sync_sched_exp_handler);
synchronize_sched_expedited_wait(rsp);
rcu_exp_gp_seq_end(rsp);
trace_rcu_exp_grace_period(rsp->name, s, TPS("end"));
trace_rcu_exp_funnel_lock(rsp->name, rnp->level,
rnp->grplo, rnp->grphi, TPS("rel"));
mutex_unlock(&rnp->exp_funnel_mutex);
}
EXPORT_SYMBOL_GPL(synchronize_sched_expedited);

3
kernel/rcu/tree_plugin.h
View File

@ -750,12 +750,14 @@ void synchronize_rcu_expedited(void)
}
s = rcu_exp_gp_seq_snap(rsp);
trace_rcu_exp_grace_period(rsp->name, s, TPS("snap"));
rnp_unlock = exp_funnel_lock(rsp, s);
if (rnp_unlock == NULL)
return; /* Someone else did our work for us. */
rcu_exp_gp_seq_start(rsp);
trace_rcu_exp_grace_period(rsp->name, s, TPS("start"));
/* Initialize the rcu_node tree in preparation for the wait. */
sync_rcu_exp_select_cpus(rsp, sync_rcu_exp_handler);
@ -766,6 +768,7 @@ void synchronize_rcu_expedited(void)
/* Clean up and exit. */
rcu_exp_gp_seq_end(rsp);
trace_rcu_exp_grace_period(rsp->name, s, TPS("end"));
mutex_unlock(&rnp_unlock->exp_funnel_mutex);
trace_rcu_exp_funnel_lock(rsp->name, rnp_unlock->level,
rnp_unlock->grplo, rnp_unlock->grphi,