* Re: [PATCH v2] sched/features: Fix !CONFIG_JUMP_LABEL case
2020-10-13 5:31 [PATCH v2] sched/features: Fix !CONFIG_JUMP_LABEL case Juri Lelli
@ 2020-10-13 8:26 ` Patrick Bellasi
2020-10-13 10:48 ` Juri Lelli
2020-10-13 10:02 ` [tip: sched/urgent] " tip-bot2 for Juri Lelli
2020-10-14 17:58 ` tip-bot2 for Juri Lelli
2 siblings, 1 reply; 5+ messages in thread
From: Patrick Bellasi @ 2020-10-13 8:26 UTC (permalink / raw)
To: Juri Lelli
Cc: peterz, mingo, linux-kernel, bristot, vincent.guittot,
dietmar.eggemann, chris.redpath, rostedt, bsegall, mgorman,
valentin.schneider
On Tue, Oct 13, 2020 at 07:31:14 +0200, Juri Lelli <juri.lelli@redhat.com> wrote...
> Commit 765cc3a4b224e ("sched/core: Optimize sched_feat() for
> !CONFIG_SCHED_DEBUG builds") made sched features static for
> !CONFIG_SCHED_DEBUG configurations, but overlooked the CONFIG_
> SCHED_DEBUG enabled and !CONFIG_JUMP_LABEL cases. For the latter echoing
> changes to /sys/kernel/debug/sched_features has the nasty effect of
> effectively changing what sched_features reports, but without actually
> changing the scheduler behaviour (since different translation units get
> different sysctl_sched_features).
Hops, yes, I think I missed to properly check that config :/
Good spot!
> Fix CONFIG_SCHED_DEBUG and !CONFIG_JUMP_LABEL configurations by properly
> restructuring ifdefs.
>
> Fixes: 765cc3a4b224e ("sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds")
> Co-developed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
> Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
(did you get some wrong formatting for the changelog above?)
> ---
> v1->v2
> - use CONFIG_JUMP_LABEL (and not the old HAVE_JUMP_LABEL) [Valentin]
> ---
> kernel/sched/core.c | 2 +-
> kernel/sched/sched.h | 13 ++++++++++---
> 2 files changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 3dc415f58bd7..a7949e3ed7e7 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -44,7 +44,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(sched_update_nr_running_tp);
>
> DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
>
> -#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
> +#ifdef CONFIG_SCHED_DEBUG
> /*
> * Debugging: various feature bits
> *
> diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
> index 28709f6b0975..8d1ca65db3b0 100644
> --- a/kernel/sched/sched.h
> +++ b/kernel/sched/sched.h
> @@ -1629,7 +1629,7 @@ enum {
>
> #undef SCHED_FEAT
>
> -#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
> +#ifdef CONFIG_SCHED_DEBUG
>
> /*
> * To support run-time toggling of sched features, all the translation units
> @@ -1637,6 +1637,7 @@ enum {
> */
> extern const_debug unsigned int sysctl_sched_features;
>
> +#ifdef CONFIG_JUMP_LABEL
> #define SCHED_FEAT(name, enabled) \
> static __always_inline bool static_branch_##name(struct static_key *key) \
> { \
> @@ -1649,7 +1650,13 @@ static __always_inline bool static_branch_##name(struct static_key *key) \
> extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
> #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
>
> -#else /* !(SCHED_DEBUG && CONFIG_JUMP_LABEL) */
> +#else /* !CONFIG_JUMP_LABEL */
> +
> +#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
> +
> +#endif /* CONFIG_JUMP_LABEL */
> +
> +#else /* !SCHED_DEBUG */
>
> /*
> * Each translation unit has its own copy of sysctl_sched_features to allow
> @@ -1665,7 +1672,7 @@ static const_debug __maybe_unused unsigned int sysctl_sched_features =
>
> #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
>
> -#endif /* SCHED_DEBUG && CONFIG_JUMP_LABEL */
> +#endif /* SCHED_DEBUG */
>
> extern struct static_key_false sched_numa_balancing;
> extern struct static_key_false sched_schedstats;
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH v2] sched/features: Fix !CONFIG_JUMP_LABEL case
2020-10-13 8:26 ` Patrick Bellasi
@ 2020-10-13 10:48 ` Juri Lelli
0 siblings, 0 replies; 5+ messages in thread
From: Juri Lelli @ 2020-10-13 10:48 UTC (permalink / raw)
To: Patrick Bellasi
Cc: peterz, mingo, linux-kernel, bristot, vincent.guittot,
dietmar.eggemann, chris.redpath, rostedt, bsegall, mgorman,
valentin.schneider
On 13/10/20 10:26, Patrick Bellasi wrote:
>
> On Tue, Oct 13, 2020 at 07:31:14 +0200, Juri Lelli <juri.lelli@redhat.com> wrote...
>
> > Commit 765cc3a4b224e ("sched/core: Optimize sched_feat() for
> > !CONFIG_SCHED_DEBUG builds") made sched features static for
> > !CONFIG_SCHED_DEBUG configurations, but overlooked the CONFIG_
> > SCHED_DEBUG enabled and !CONFIG_JUMP_LABEL cases. For the latter echoing
> > changes to /sys/kernel/debug/sched_features has the nasty effect of
> > effectively changing what sched_features reports, but without actually
> > changing the scheduler behaviour (since different translation units get
> > different sysctl_sched_features).
>
> Hops, yes, I think I missed to properly check that config :/
> Good spot!
>
> > Fix CONFIG_SCHED_DEBUG and !CONFIG_JUMP_LABEL configurations by properly
> > restructuring ifdefs.
> >
> > Fixes: 765cc3a4b224e ("sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds")
> > Co-developed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
> > Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
> > Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
>
> (did you get some wrong formatting for the changelog above?)
Hummm, what you mean?
I intended to follow
https://elixir.bootlin.com/linux/latest/source/Documentation/process/submitting-patches.rst#L566
^ permalink raw reply [flat|nested] 5+ messages in thread
* [tip: sched/urgent] sched/features: Fix !CONFIG_JUMP_LABEL case
2020-10-13 5:31 [PATCH v2] sched/features: Fix !CONFIG_JUMP_LABEL case Juri Lelli
2020-10-13 8:26 ` Patrick Bellasi
@ 2020-10-13 10:02 ` tip-bot2 for Juri Lelli
2020-10-14 17:58 ` tip-bot2 for Juri Lelli
2 siblings, 0 replies; 5+ messages in thread
From: tip-bot2 for Juri Lelli @ 2020-10-13 10:02 UTC (permalink / raw)
To: linux-tip-commits
Cc: Daniel Bristot de Oliveira, Juri Lelli, Ingo Molnar,
Patrick Bellasi, x86, LKML
The following commit has been merged into the sched/urgent branch of tip:
Commit-ID: da912c29a4a552588cbfa895487d9d5523b6faa7
Gitweb: https://git.kernel.org/tip/da912c29a4a552588cbfa895487d9d5523b6faa7
Author: Juri Lelli <juri.lelli@redhat.com>
AuthorDate: Tue, 13 Oct 2020 07:31:14 +02:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Tue, 13 Oct 2020 11:33:08 +02:00
sched/features: Fix !CONFIG_JUMP_LABEL case
Commit:
765cc3a4b224e ("sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds")
made sched features static for !CONFIG_SCHED_DEBUG configurations, but
overlooked the CONFIG_SCHED_DEBUG=y and !CONFIG_JUMP_LABEL cases.
For the latter echoing changes to /sys/kernel/debug/sched_features has
the nasty effect of effectively changing what sched_features reports,
but without actually changing the scheduler behaviour (since different
translation units get different sysctl_sched_features).
Fix CONFIG_SCHED_DEBUG=y and !CONFIG_JUMP_LABEL configurations by properly
restructuring ifdefs.
Fixes: 765cc3a4b224e ("sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds")
Co-developed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Patrick Bellasi <patrick.bellasi@matbug.net>
Link: https://lore.kernel.org/r/20201013053114.160628-1-juri.lelli@redhat.com
---
kernel/sched/core.c | 2 +-
kernel/sched/sched.h | 13 ++++++++++---
2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 8160ab5..d2003a7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -44,7 +44,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(sched_update_nr_running_tp);
DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
-#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
+#ifdef CONFIG_SCHED_DEBUG
/*
* Debugging: various feature bits
*
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 28709f6..8d1ca65 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1629,7 +1629,7 @@ enum {
#undef SCHED_FEAT
-#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
+#ifdef CONFIG_SCHED_DEBUG
/*
* To support run-time toggling of sched features, all the translation units
@@ -1637,6 +1637,7 @@ enum {
*/
extern const_debug unsigned int sysctl_sched_features;
+#ifdef CONFIG_JUMP_LABEL
#define SCHED_FEAT(name, enabled) \
static __always_inline bool static_branch_##name(struct static_key *key) \
{ \
@@ -1649,7 +1650,13 @@ static __always_inline bool static_branch_##name(struct static_key *key) \
extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
-#else /* !(SCHED_DEBUG && CONFIG_JUMP_LABEL) */
+#else /* !CONFIG_JUMP_LABEL */
+
+#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
+
+#endif /* CONFIG_JUMP_LABEL */
+
+#else /* !SCHED_DEBUG */
/*
* Each translation unit has its own copy of sysctl_sched_features to allow
@@ -1665,7 +1672,7 @@ static const_debug __maybe_unused unsigned int sysctl_sched_features =
#define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
-#endif /* SCHED_DEBUG && CONFIG_JUMP_LABEL */
+#endif /* SCHED_DEBUG */
extern struct static_key_false sched_numa_balancing;
extern struct static_key_false sched_schedstats;
^ permalink raw reply related [flat|nested] 5+ messages in thread* [tip: sched/urgent] sched/features: Fix !CONFIG_JUMP_LABEL case
2020-10-13 5:31 [PATCH v2] sched/features: Fix !CONFIG_JUMP_LABEL case Juri Lelli
2020-10-13 8:26 ` Patrick Bellasi
2020-10-13 10:02 ` [tip: sched/urgent] " tip-bot2 for Juri Lelli
@ 2020-10-14 17:58 ` tip-bot2 for Juri Lelli
2 siblings, 0 replies; 5+ messages in thread
From: tip-bot2 for Juri Lelli @ 2020-10-14 17:58 UTC (permalink / raw)
To: linux-tip-commits
Cc: Daniel Bristot de Oliveira, Juri Lelli, Ingo Molnar,
Patrick Bellasi, Valentin Schneider, x86, LKML
The following commit has been merged into the sched/urgent branch of tip:
Commit-ID: a73f863af4ce9730795eab7097fb2102e6854365
Gitweb: https://git.kernel.org/tip/a73f863af4ce9730795eab7097fb2102e6854365
Author: Juri Lelli <juri.lelli@redhat.com>
AuthorDate: Tue, 13 Oct 2020 07:31:14 +02:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Wed, 14 Oct 2020 19:55:46 +02:00
sched/features: Fix !CONFIG_JUMP_LABEL case
Commit:
765cc3a4b224e ("sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds")
made sched features static for !CONFIG_SCHED_DEBUG configurations, but
overlooked the CONFIG_SCHED_DEBUG=y and !CONFIG_JUMP_LABEL cases.
For the latter echoing changes to /sys/kernel/debug/sched_features has
the nasty effect of effectively changing what sched_features reports,
but without actually changing the scheduler behaviour (since different
translation units get different sysctl_sched_features).
Fix CONFIG_SCHED_DEBUG=y and !CONFIG_JUMP_LABEL configurations by properly
restructuring ifdefs.
Fixes: 765cc3a4b224e ("sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds")
Co-developed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Patrick Bellasi <patrick.bellasi@matbug.net>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lore.kernel.org/r/20201013053114.160628-1-juri.lelli@redhat.com
---
kernel/sched/core.c | 2 +-
kernel/sched/sched.h | 13 ++++++++++---
2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 8160ab5..d2003a7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -44,7 +44,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(sched_update_nr_running_tp);
DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
-#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
+#ifdef CONFIG_SCHED_DEBUG
/*
* Debugging: various feature bits
*
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 648f023..df80bfc 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1629,7 +1629,7 @@ enum {
#undef SCHED_FEAT
-#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
+#ifdef CONFIG_SCHED_DEBUG
/*
* To support run-time toggling of sched features, all the translation units
@@ -1637,6 +1637,7 @@ enum {
*/
extern const_debug unsigned int sysctl_sched_features;
+#ifdef CONFIG_JUMP_LABEL
#define SCHED_FEAT(name, enabled) \
static __always_inline bool static_branch_##name(struct static_key *key) \
{ \
@@ -1649,7 +1650,13 @@ static __always_inline bool static_branch_##name(struct static_key *key) \
extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
-#else /* !(SCHED_DEBUG && CONFIG_JUMP_LABEL) */
+#else /* !CONFIG_JUMP_LABEL */
+
+#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
+
+#endif /* CONFIG_JUMP_LABEL */
+
+#else /* !SCHED_DEBUG */
/*
* Each translation unit has its own copy of sysctl_sched_features to allow
@@ -1665,7 +1672,7 @@ static const_debug __maybe_unused unsigned int sysctl_sched_features =
#define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
-#endif /* SCHED_DEBUG && CONFIG_JUMP_LABEL */
+#endif /* SCHED_DEBUG */
extern struct static_key_false sched_numa_balancing;
extern struct static_key_false sched_schedstats;
^ permalink raw reply related [flat|nested] 5+ messages in thread