Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On Wed, May 14, 2014 at 08:57:06AM -0700, Paul E. McKenney wrote: > On Wed, May 14, 2014 at 08:41:50AM -0700, Josh Triplett wrote: > > On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: > > > From: Uma Sharma > > > > > > The variable and struct both having the name "rcu_state" confuses > > > sparse in some situations, so this commit changes the variable to > > > "rcu_state_p" in order to avoid this confusion. This also makes > > > things easier for human readers. > > > > Human readers aside, how does Sparse get confused? Let's fix that. > > OK. The issue appears to be that we have a variable with the same > name as a struct, as in: > > struct rcu_state *rcu_state; Which is completely legal C, and Sparse should have no issue with it. > > Personally, I don't think the _p makes things particularly easier for > > human readers, but it doesn't make things *harder* for anyone other than > > those used to reading the existing code, so, *shrug*. > > It does make it a bit easier for me when grepping through the source, > given the large number of "struct rcu_state" strings in there. And > yes, I should be using some more modern tools than "grep" and "cscope"! > But I am not the only throwback. ;-) Count me in as someone using "grep" as well (usually via "git grep"). - Josh Triplett -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On Wed, May 14, 2014 at 08:41:50AM -0700, Josh Triplett wrote: > On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: > > From: Uma Sharma > > > > The variable and struct both having the name "rcu_state" confuses > > sparse in some situations, so this commit changes the variable to > > "rcu_state_p" in order to avoid this confusion. This also makes > > things easier for human readers. > > Human readers aside, how does Sparse get confused? Let's fix that. OK. The issue appears to be that we have a variable with the same name as a struct, as in: struct rcu_state *rcu_state; Of course, now I don't recall the details or the kernel version, other than that the name change cleared things up. :-/ > Personally, I don't think the _p makes things particularly easier for > human readers, but it doesn't make things *harder* for anyone other than > those used to reading the existing code, so, *shrug*. It does make it a bit easier for me when grepping through the source, given the large number of "struct rcu_state" strings in there. And yes, I should be using some more modern tools than "grep" and "cscope"! But I am not the only throwback. ;-) Thanx, Paul -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On 05/14/2014 08:41 AM, Josh Triplett wrote: > On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: >> From: Uma Sharma >> >> The variable and struct both having the name "rcu_state" confuses >> sparse in some situations, so this commit changes the variable to >> "rcu_state_p" in order to avoid this confusion. This also makes >> things easier for human readers. > > Human readers aside, how does Sparse get confused? Let's fix that. ack that. Has it been reported on linux-sparse mailing list? > Personally, I don't think the _p makes things particularly easier for > human readers, but it doesn't make things *harder* for anyone other than > those used to reading the existing code, so, *shrug*. -- ~Randy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: > From: Uma Sharma > > The variable and struct both having the name "rcu_state" confuses > sparse in some situations, so this commit changes the variable to > "rcu_state_p" in order to avoid this confusion. This also makes > things easier for human readers. Human readers aside, how does Sparse get confused? Let's fix that. Personally, I don't think the _p makes things particularly easier for human readers, but it doesn't make things *harder* for anyone other than those used to reading the existing code, so, *shrug*. - Josh Triplett -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: From: Uma Sharma uma.sharma...@gmail.com The variable and struct both having the name rcu_state confuses sparse in some situations, so this commit changes the variable to rcu_state_p in order to avoid this confusion. This also makes things easier for human readers. Human readers aside, how does Sparse get confused? Let's fix that. Personally, I don't think the _p makes things particularly easier for human readers, but it doesn't make things *harder* for anyone other than those used to reading the existing code, so, *shrug*. - Josh Triplett -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On 05/14/2014 08:41 AM, Josh Triplett wrote: On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: From: Uma Sharma uma.sharma...@gmail.com The variable and struct both having the name rcu_state confuses sparse in some situations, so this commit changes the variable to rcu_state_p in order to avoid this confusion. This also makes things easier for human readers. Human readers aside, how does Sparse get confused? Let's fix that. ack that. Has it been reported on linux-sparse mailing list? Personally, I don't think the _p makes things particularly easier for human readers, but it doesn't make things *harder* for anyone other than those used to reading the existing code, so, *shrug*. -- ~Randy -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On Wed, May 14, 2014 at 08:41:50AM -0700, Josh Triplett wrote: On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: From: Uma Sharma uma.sharma...@gmail.com The variable and struct both having the name rcu_state confuses sparse in some situations, so this commit changes the variable to rcu_state_p in order to avoid this confusion. This also makes things easier for human readers. Human readers aside, how does Sparse get confused? Let's fix that. OK. The issue appears to be that we have a variable with the same name as a struct, as in: struct rcu_state *rcu_state; Of course, now I don't recall the details or the kernel version, other than that the name change cleared things up. :-/ Personally, I don't think the _p makes things particularly easier for human readers, but it doesn't make things *harder* for anyone other than those used to reading the existing code, so, *shrug*. It does make it a bit easier for me when grepping through the source, given the large number of struct rcu_state strings in there. And yes, I should be using some more modern tools than grep and cscope! But I am not the only throwback. ;-) Thanx, Paul -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
On Wed, May 14, 2014 at 08:57:06AM -0700, Paul E. McKenney wrote: On Wed, May 14, 2014 at 08:41:50AM -0700, Josh Triplett wrote: On Tue, May 13, 2014 at 05:30:59PM -0700, Paul E. McKenney wrote: From: Uma Sharma uma.sharma...@gmail.com The variable and struct both having the name rcu_state confuses sparse in some situations, so this commit changes the variable to rcu_state_p in order to avoid this confusion. This also makes things easier for human readers. Human readers aside, how does Sparse get confused? Let's fix that. OK. The issue appears to be that we have a variable with the same name as a struct, as in: struct rcu_state *rcu_state; Which is completely legal C, and Sparse should have no issue with it. Personally, I don't think the _p makes things particularly easier for human readers, but it doesn't make things *harder* for anyone other than those used to reading the existing code, so, *shrug*. It does make it a bit easier for me when grepping through the source, given the large number of struct rcu_state strings in there. And yes, I should be using some more modern tools than grep and cscope! But I am not the only throwback. ;-) Count me in as someone using grep as well (usually via git grep). - Josh Triplett -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
From: Uma Sharma
The variable and struct both having the name "rcu_state" confuses
sparse in some situations, so this commit changes the variable to
"rcu_state_p" in order to avoid this confusion. This also makes
things easier for human readers.
Signed-off-by: Uma Sharma
[ paulmck: Changed the declaration and several additional uses. ]
Signed-off-by: Paul E. McKenney
---
kernel/rcu/tree.c| 16
kernel/rcu/tree_plugin.h | 16
2 files changed, 16 insertions(+), 16 deletions(-)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 3bbe48939e47..3e3f13e8b429 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -101,7 +101,7 @@ DEFINE_PER_CPU(struct rcu_data, sname##_data)
RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched);
RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh);
-static struct rcu_state *rcu_state;
+static struct rcu_state *rcu_state_p;
LIST_HEAD(rcu_struct_flavors);
/* Increase (but not decrease) the CONFIG_RCU_FANOUT_LEAF at boot time. */
@@ -275,7 +275,7 @@ EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
*/
void rcu_force_quiescent_state(void)
{
- force_quiescent_state(rcu_state);
+ force_quiescent_state(rcu_state_p);
}
EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
@@ -327,7 +327,7 @@ void rcutorture_get_gp_data(enum rcutorture_type test_type,
int *flags,
switch (test_type) {
case RCU_FLAVOR:
- rsp = rcu_state;
+ rsp = rcu_state_p;
break;
case RCU_BH_FLAVOR:
rsp = _bh_state;
@@ -910,7 +910,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp,
* we will beat on the first one until it gets unstuck, then move
* to the next. Only do this for the primary flavor of RCU.
*/
- if (rdp->rsp == rcu_state &&
+ if (rdp->rsp == rcu_state_p &&
ULONG_CMP_GE(jiffies, rdp->rsp->jiffies_resched)) {
rdp->rsp->jiffies_resched += 5;
resched_cpu(rdp->cpu);
@@ -2660,7 +2660,7 @@ EXPORT_SYMBOL_GPL(call_rcu_bh);
void kfree_call_rcu(struct rcu_head *head,
void (*func)(struct rcu_head *rcu))
{
- __call_rcu(head, func, rcu_state, -1, 1);
+ __call_rcu(head, func, rcu_state_p, -1, 1);
}
EXPORT_SYMBOL_GPL(kfree_call_rcu);
@@ -2787,7 +2787,7 @@ unsigned long get_state_synchronize_rcu(void)
* time-consuming work between get_state_synchronize_rcu()
* and cond_synchronize_rcu().
*/
- return smp_load_acquire(_state->gpnum);
+ return smp_load_acquire(_state_p->gpnum);
}
EXPORT_SYMBOL_GPL(get_state_synchronize_rcu);
@@ -2813,7 +2813,7 @@ void cond_synchronize_rcu(unsigned long oldstate)
* Ensure that this load happens before any RCU-destructive
* actions the caller might carry out after we return.
*/
- newstate = smp_load_acquire(_state->completed);
+ newstate = smp_load_acquire(_state_p->completed);
if (ULONG_CMP_GE(oldstate, newstate))
synchronize_rcu();
}
@@ -3354,7 +3354,7 @@ static int rcu_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
long cpu = (long)hcpu;
- struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
+ struct rcu_data *rdp = per_cpu_ptr(rcu_state_p->rda, cpu);
struct rcu_node *rnp = rdp->mynode;
struct rcu_state *rsp;
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 2e579c38bd91..29977ae84e7e 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -116,7 +116,7 @@ static void __init rcu_bootup_announce_oddness(void)
#ifdef CONFIG_TREE_PREEMPT_RCU
RCU_STATE_INITIALIZER(rcu_preempt, 'p', call_rcu);
-static struct rcu_state *rcu_state = _preempt_state;
+static struct rcu_state *rcu_state_p = _preempt_state;
static int rcu_preempted_readers_exp(struct rcu_node *rnp);
@@ -947,7 +947,7 @@ void exit_rcu(void)
#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
-static struct rcu_state *rcu_state = _sched_state;
+static struct rcu_state *rcu_state_p = _sched_state;
/*
* Tell them what RCU they are running.
@@ -1468,11 +1468,11 @@ static int __init rcu_spawn_kthreads(void)
for_each_possible_cpu(cpu)
per_cpu(rcu_cpu_has_work, cpu) = 0;
BUG_ON(smpboot_register_percpu_thread(_cpu_thread_spec));
- rnp = rcu_get_root(rcu_state);
- (void)rcu_spawn_one_boost_kthread(rcu_state, rnp);
+ rnp = rcu_get_root(rcu_state_p);
+ (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp);
if (NUM_RCU_NODES > 1) {
- rcu_for_each_leaf_node(rcu_state, rnp)
- (void)rcu_spawn_one_boost_kthread(rcu_state, rnp);
+ rcu_for_each_leaf_node(rcu_state_p, rnp)
+ (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp);
}
return 0;
}
@@ -1480,12 +1480,12 @@
[PATCH tip/core/rcu 1/1] rcu: Variable name changed in tree_plugin.h and used in tree.c
From: Uma Sharma uma.sharma...@gmail.com
The variable and struct both having the name rcu_state confuses
sparse in some situations, so this commit changes the variable to
rcu_state_p in order to avoid this confusion. This also makes
things easier for human readers.
Signed-off-by: Uma Sharma uma.sharma...@gmail.com
[ paulmck: Changed the declaration and several additional uses. ]
Signed-off-by: Paul E. McKenney paul...@linux.vnet.ibm.com
---
kernel/rcu/tree.c| 16
kernel/rcu/tree_plugin.h | 16
2 files changed, 16 insertions(+), 16 deletions(-)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 3bbe48939e47..3e3f13e8b429 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -101,7 +101,7 @@ DEFINE_PER_CPU(struct rcu_data, sname##_data)
RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched);
RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh);
-static struct rcu_state *rcu_state;
+static struct rcu_state *rcu_state_p;
LIST_HEAD(rcu_struct_flavors);
/* Increase (but not decrease) the CONFIG_RCU_FANOUT_LEAF at boot time. */
@@ -275,7 +275,7 @@ EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
*/
void rcu_force_quiescent_state(void)
{
- force_quiescent_state(rcu_state);
+ force_quiescent_state(rcu_state_p);
}
EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
@@ -327,7 +327,7 @@ void rcutorture_get_gp_data(enum rcutorture_type test_type,
int *flags,
switch (test_type) {
case RCU_FLAVOR:
- rsp = rcu_state;
+ rsp = rcu_state_p;
break;
case RCU_BH_FLAVOR:
rsp = rcu_bh_state;
@@ -910,7 +910,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp,
* we will beat on the first one until it gets unstuck, then move
* to the next. Only do this for the primary flavor of RCU.
*/
- if (rdp-rsp == rcu_state
+ if (rdp-rsp == rcu_state_p
ULONG_CMP_GE(jiffies, rdp-rsp-jiffies_resched)) {
rdp-rsp-jiffies_resched += 5;
resched_cpu(rdp-cpu);
@@ -2660,7 +2660,7 @@ EXPORT_SYMBOL_GPL(call_rcu_bh);
void kfree_call_rcu(struct rcu_head *head,
void (*func)(struct rcu_head *rcu))
{
- __call_rcu(head, func, rcu_state, -1, 1);
+ __call_rcu(head, func, rcu_state_p, -1, 1);
}
EXPORT_SYMBOL_GPL(kfree_call_rcu);
@@ -2787,7 +2787,7 @@ unsigned long get_state_synchronize_rcu(void)
* time-consuming work between get_state_synchronize_rcu()
* and cond_synchronize_rcu().
*/
- return smp_load_acquire(rcu_state-gpnum);
+ return smp_load_acquire(rcu_state_p-gpnum);
}
EXPORT_SYMBOL_GPL(get_state_synchronize_rcu);
@@ -2813,7 +2813,7 @@ void cond_synchronize_rcu(unsigned long oldstate)
* Ensure that this load happens before any RCU-destructive
* actions the caller might carry out after we return.
*/
- newstate = smp_load_acquire(rcu_state-completed);
+ newstate = smp_load_acquire(rcu_state_p-completed);
if (ULONG_CMP_GE(oldstate, newstate))
synchronize_rcu();
}
@@ -3354,7 +3354,7 @@ static int rcu_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
long cpu = (long)hcpu;
- struct rcu_data *rdp = per_cpu_ptr(rcu_state-rda, cpu);
+ struct rcu_data *rdp = per_cpu_ptr(rcu_state_p-rda, cpu);
struct rcu_node *rnp = rdp-mynode;
struct rcu_state *rsp;
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 2e579c38bd91..29977ae84e7e 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -116,7 +116,7 @@ static void __init rcu_bootup_announce_oddness(void)
#ifdef CONFIG_TREE_PREEMPT_RCU
RCU_STATE_INITIALIZER(rcu_preempt, 'p', call_rcu);
-static struct rcu_state *rcu_state = rcu_preempt_state;
+static struct rcu_state *rcu_state_p = rcu_preempt_state;
static int rcu_preempted_readers_exp(struct rcu_node *rnp);
@@ -947,7 +947,7 @@ void exit_rcu(void)
#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
-static struct rcu_state *rcu_state = rcu_sched_state;
+static struct rcu_state *rcu_state_p = rcu_sched_state;
/*
* Tell them what RCU they are running.
@@ -1468,11 +1468,11 @@ static int __init rcu_spawn_kthreads(void)
for_each_possible_cpu(cpu)
per_cpu(rcu_cpu_has_work, cpu) = 0;
BUG_ON(smpboot_register_percpu_thread(rcu_cpu_thread_spec));
- rnp = rcu_get_root(rcu_state);
- (void)rcu_spawn_one_boost_kthread(rcu_state, rnp);
+ rnp = rcu_get_root(rcu_state_p);
+ (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp);
if (NUM_RCU_NODES 1) {
- rcu_for_each_leaf_node(rcu_state, rnp)
- (void)rcu_spawn_one_boost_kthread(rcu_state, rnp);
+ rcu_for_each_leaf_node(rcu_state_p, rnp)
+
