* [PATCH -next] sched: Use struct_size() helper in task_numa_group()
@ 2021-12-21 13:21 Xiu Jianfeng
2022-01-06 16:39 ` Steven Rostedt
0 siblings, 1 reply; 7+ messages in thread
From: Xiu Jianfeng @ 2021-12-21 13:21 UTC (permalink / raw)
To: mingo, peterz, juri.lelli, vincent.guittot, dietmar.eggemann,
rostedt, bsegall, mgorman, bristot
Cc: linux-kernel
Make use of struct_size() helper instead of an open-coded calculation.
There is no functional change in this patch.
Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
---
kernel/sched/fair.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 095b0aa378df..265e37be0c92 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2437,11 +2437,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
int i;
if (unlikely(!deref_curr_numa_group(p))) {
- unsigned int size = sizeof(struct numa_group) +
- NR_NUMA_HINT_FAULT_STATS *
- nr_node_ids * sizeof(unsigned long);
-
- grp = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
+ grp = kzalloc(struct_size(grp, faults, NR_NUMA_HINT_FAULT_STATS * nr_node_ids),
+ GFP_KERNEL | __GFP_NOWARN);
if (!grp)
return;
--
2.17.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [PATCH -next] sched: Use struct_size() helper in task_numa_group()
2021-12-21 13:21 [PATCH -next] sched: Use struct_size() helper in task_numa_group() Xiu Jianfeng
@ 2022-01-06 16:39 ` Steven Rostedt
0 siblings, 0 replies; 7+ messages in thread
From: Steven Rostedt @ 2022-01-06 16:39 UTC (permalink / raw)
To: Xiu Jianfeng
Cc: mingo, peterz, juri.lelli, vincent.guittot, dietmar.eggemann,
bsegall, mgorman, bristot, linux-kernel
On Tue, 21 Dec 2021 21:21:38 +0800
Xiu Jianfeng <xiujianfeng@huawei.com> wrote:
> Make use of struct_size() helper instead of an open-coded calculation.
> There is no functional change in this patch.
I'm all for this clean up, but...
>
> Link: https://github.com/KSPP/linux/issues/160
> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
> ---
> kernel/sched/fair.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 095b0aa378df..265e37be0c92 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -2437,11 +2437,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
> int i;
>
> if (unlikely(!deref_curr_numa_group(p))) {
> - unsigned int size = sizeof(struct numa_group) +
> - NR_NUMA_HINT_FAULT_STATS *
> - nr_node_ids * sizeof(unsigned long);
> -
> - grp = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
> + grp = kzalloc(struct_size(grp, faults, NR_NUMA_HINT_FAULT_STATS * nr_node_ids),
> + GFP_KERNEL | __GFP_NOWARN);
Ug, the above is so ugly. Why remove the size variable?
unsigned int size = struct_size(grp, faults,
NR_NUMA_HINT_FAULT_STATS * nr_node_ids);
-- Steve
> if (!grp)
> return;
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH -next] sched: Use struct_size() helper in task_numa_group()
@ 2022-01-07 2:52 Xiu Jianfeng
2022-01-07 14:36 ` Steven Rostedt
2022-01-10 16:06 ` Peter Zijlstra
0 siblings, 2 replies; 7+ messages in thread
From: Xiu Jianfeng @ 2022-01-07 2:52 UTC (permalink / raw)
To: mingo, peterz, juri.lelli, vincent.guittot, dietmar.eggemann,
rostedt, bsegall, mgorman, bristot, gustavoars
Cc: linux-kernel, linux-hardening
Make use of struct_size() helper instead of an open-coded calculation.
There is no functional change in this patch.
Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
---
kernel/sched/fair.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 095b0aa378df..265e37be0c92 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2437,11 +2437,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
int i;
if (unlikely(!deref_curr_numa_group(p))) {
- unsigned int size = sizeof(struct numa_group) +
- NR_NUMA_HINT_FAULT_STATS *
- nr_node_ids * sizeof(unsigned long);
-
- grp = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
+ grp = kzalloc(struct_size(grp, faults, NR_NUMA_HINT_FAULT_STATS * nr_node_ids),
+ GFP_KERNEL | __GFP_NOWARN);
if (!grp)
return;
--
2.17.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [PATCH -next] sched: Use struct_size() helper in task_numa_group()
2022-01-07 2:52 Xiu Jianfeng
@ 2022-01-07 14:36 ` Steven Rostedt
2022-01-10 1:20 ` xiujianfeng
2022-01-10 16:06 ` Peter Zijlstra
1 sibling, 1 reply; 7+ messages in thread
From: Steven Rostedt @ 2022-01-07 14:36 UTC (permalink / raw)
To: Xiu Jianfeng
Cc: mingo, peterz, juri.lelli, vincent.guittot, dietmar.eggemann,
bsegall, mgorman, bristot, gustavoars, linux-kernel,
linux-hardening
On Fri, 7 Jan 2022 10:52:12 +0800
Xiu Jianfeng <xiujianfeng@huawei.com> wrote:
> Make use of struct_size() helper instead of an open-coded calculation.
> There is no functional change in this patch.
>
> Link: https://github.com/KSPP/linux/issues/160
> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
> ---
> kernel/sched/fair.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 095b0aa378df..265e37be0c92 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -2437,11 +2437,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
> int i;
>
> if (unlikely(!deref_curr_numa_group(p))) {
> - unsigned int size = sizeof(struct numa_group) +
> - NR_NUMA_HINT_FAULT_STATS *
> - nr_node_ids * sizeof(unsigned long);
> -
> - grp = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
> + grp = kzalloc(struct_size(grp, faults, NR_NUMA_HINT_FAULT_STATS * nr_node_ids),
> + GFP_KERNEL | __GFP_NOWARN);
I just replied yesterday. Keep the size variable. The above is too much for
a kzalloc().
-- Steve
> if (!grp)
> return;
>
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH -next] sched: Use struct_size() helper in task_numa_group()
2022-01-07 14:36 ` Steven Rostedt
@ 2022-01-10 1:20 ` xiujianfeng
0 siblings, 0 replies; 7+ messages in thread
From: xiujianfeng @ 2022-01-10 1:20 UTC (permalink / raw)
To: Steven Rostedt
Cc: mingo, peterz, juri.lelli, vincent.guittot, dietmar.eggemann,
bsegall, mgorman, bristot, gustavoars, linux-kernel,
linux-hardening
在 2022/1/7 22:36, Steven Rostedt 写道:
> On Fri, 7 Jan 2022 10:52:12 +0800
> Xiu Jianfeng <xiujianfeng@huawei.com> wrote:
>
>> Make use of struct_size() helper instead of an open-coded calculation.
>> There is no functional change in this patch.
>>
>> Link: https://github.com/KSPP/linux/issues/160
>> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
>> ---
>> kernel/sched/fair.c | 7 ++-----
>> 1 file changed, 2 insertions(+), 5 deletions(-)
>>
>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
>> index 095b0aa378df..265e37be0c92 100644
>> --- a/kernel/sched/fair.c
>> +++ b/kernel/sched/fair.c
>> @@ -2437,11 +2437,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
>> int i;
>>
>> if (unlikely(!deref_curr_numa_group(p))) {
>> - unsigned int size = sizeof(struct numa_group) +
>> - NR_NUMA_HINT_FAULT_STATS *
>> - nr_node_ids * sizeof(unsigned long);
>> -
>> - grp = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
>> + grp = kzalloc(struct_size(grp, faults, NR_NUMA_HINT_FAULT_STATS * nr_node_ids),
>> + GFP_KERNEL | __GFP_NOWARN);
> I just replied yesterday. Keep the size variable. The above is too much for
> a kzalloc().
thanks, I may missed your reply mail, I'll modify and resend this patch.
>
> -- Steve
>
>
>
>
>> if (!grp)
>> return;
>>
> .
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH -next] sched: Use struct_size() helper in task_numa_group()
2022-01-07 2:52 Xiu Jianfeng
2022-01-07 14:36 ` Steven Rostedt
@ 2022-01-10 16:06 ` Peter Zijlstra
2022-01-10 16:11 ` Steven Rostedt
1 sibling, 1 reply; 7+ messages in thread
From: Peter Zijlstra @ 2022-01-10 16:06 UTC (permalink / raw)
To: Xiu Jianfeng
Cc: mingo, juri.lelli, vincent.guittot, dietmar.eggemann, rostedt,
bsegall, mgorman, bristot, gustavoars, linux-kernel,
linux-hardening
On Fri, Jan 07, 2022 at 10:52:12AM +0800, Xiu Jianfeng wrote:
> Make use of struct_size() helper instead of an open-coded calculation.
> There is no functional change in this patch.
Why ?!? This makes something that was trivial to read into something
weird.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH -next] sched: Use struct_size() helper in task_numa_group()
2022-01-10 16:06 ` Peter Zijlstra
@ 2022-01-10 16:11 ` Steven Rostedt
0 siblings, 0 replies; 7+ messages in thread
From: Steven Rostedt @ 2022-01-10 16:11 UTC (permalink / raw)
To: Peter Zijlstra
Cc: Xiu Jianfeng, mingo, juri.lelli, vincent.guittot,
dietmar.eggemann, bsegall, mgorman, bristot, gustavoars,
linux-kernel, linux-hardening
On Mon, 10 Jan 2022 17:06:30 +0100
Peter Zijlstra <peterz@infradead.org> wrote:
> On Fri, Jan 07, 2022 at 10:52:12AM +0800, Xiu Jianfeng wrote:
> > Make use of struct_size() helper instead of an open-coded calculation.
> > There is no functional change in this patch.
>
> Why ?!? This makes something that was trivial to read into something
> weird.
Please take his last patch (which only modifies the update to size) and
makes it more robust.
https://lore.kernel.org/all/20220110012354.144394-1-xiujianfeng@huawei.com/
Which is much easier to read.
We should really replace all open coded struct_size() code.
-- Steve
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2022-01-10 16:11 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
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2021-12-21 13:21 [PATCH -next] sched: Use struct_size() helper in task_numa_group() Xiu Jianfeng
2022-01-06 16:39 ` Steven Rostedt
2022-01-07 2:52 Xiu Jianfeng
2022-01-07 14:36 ` Steven Rostedt
2022-01-10 1:20 ` xiujianfeng
2022-01-10 16:06 ` Peter Zijlstra
2022-01-10 16:11 ` Steven Rostedt
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