Re: [PATCH v2] kvm: remove dependence on delay-accounting
On Sat, Jan 14, 2012 at 08:30:51PM +0400, Konstantin Khlebnikov wrote:
KVM selects delay-accounting only to get sched-info for steal-time accounting.
Meanwhile delay-accounting can be disabled by boot option. This is ridiculous.
This patch adds internal boolean option CONFIG_TASK_SCHED_INFO to enable only
task-sched_info and its collecting inside scheduler.
v2:
* stupid misprint fixed
Signed-off-by: Konstantin Khlebnikov khlebni...@openvz.org
---
arch/x86/kvm/Kconfig |5 +
include/linux/sched.h |6 ++
init/Kconfig |7 +++
kernel/sched/core.c |2 +-
kernel/sched/stats.h |4 ++--
lib/Kconfig.debug |1 +
6 files changed, 14 insertions(+), 11 deletions(-)
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 1a7fe86..e3952e8 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -22,8 +22,6 @@ config KVM
depends on HAVE_KVM
# for device assignment:
depends on PCI
- # for TASKSTATS/TASK_DELAY_ACCT:
- depends on NET
select PREEMPT_NOTIFIERS
select MMU_NOTIFIER
select ANON_INODES
@@ -33,8 +31,7 @@ config KVM
select KVM_ASYNC_PF
select USER_RETURN_NOTIFIER
select KVM_MMIO
- select TASKSTATS
- select TASK_DELAY_ACCT
+ select TASK_SCHED_INFO
select PERF_EVENTS
---help---
Support hosting fully virtualized guest machines using hardware
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 868cb83..dd5bf78 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -734,7 +734,6 @@ extern struct user_struct root_user;
struct backing_dev_info;
-#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
struct sched_info {
/* cumulative counters */
unsigned long pcount; /* # of times run on this cpu */
@@ -744,7 +743,6 @@ struct sched_info {
unsigned long long last_arrival,/* when we last ran on a cpu */
last_queued; /* when we were last queued to run */
};
-#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info {
@@ -782,7 +780,7 @@ struct task_delay_info {
static inline int sched_info_on(void)
{
-#ifdef CONFIG_SCHEDSTATS
+#if IS_ENABLED(CONFIG_SCHEDSTATS) || IS_ENABLED(CONFIG_KVM)
return 1;
CONFIG_TASK_SCHED_INFO?
--
To unsubscribe from this list: send the line unsubscribe kvm in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v2] kvm: remove dependence on delay-accounting
On Sat, 2012-01-14 at 20:30 +0400, Konstantin Khlebnikov wrote:
KVM selects delay-accounting only to get sched-info for steal-time accounting.
Meanwhile delay-accounting can be disabled by boot option. This is ridiculous.
This patch adds internal boolean option CONFIG_TASK_SCHED_INFO to enable only
task-sched_info and its collecting inside scheduler.
Urgh, more stupid config knobs, we should be removing them, not adding
moar.
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 868cb83..dd5bf78 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -734,7 +734,6 @@ extern struct user_struct root_user;
struct backing_dev_info;
-#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
struct sched_info {
/* cumulative counters */
unsigned long pcount; /* # of times run on this cpu */
@@ -744,7 +743,6 @@ struct sched_info {
unsigned long long last_arrival,/* when we last ran on a cpu */
last_queued; /* when we were last queued to run */
};
-#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
Not having that structure helps with compile errors.
#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info {
@@ -782,7 +780,7 @@ struct task_delay_info {
static inline int sched_info_on(void)
{
-#ifdef CONFIG_SCHEDSTATS
+#if IS_ENABLED(CONFIG_SCHEDSTATS) || IS_ENABLED(CONFIG_KVM)
WTF is IS_ENABLED and why do you use it?
Not much like this stuff.
--
To unsubscribe from this list: send the line unsubscribe kvm in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v2] kvm: remove dependence on delay-accounting
Marcelo Tosatti wrote:
On Sat, Jan 14, 2012 at 08:30:51PM +0400, Konstantin Khlebnikov wrote:
KVM selects delay-accounting only to get sched-info for steal-time accounting.
Meanwhile delay-accounting can be disabled by boot option. This is ridiculous.
This patch adds internal boolean option CONFIG_TASK_SCHED_INFO to enable only
task-sched_info and its collecting inside scheduler.
cut
static inline int sched_info_on(void)
{
-#ifdef CONFIG_SCHEDSTATS
+#if IS_ENABLED(CONFIG_SCHEDSTATS) || IS_ENABLED(CONFIG_KVM)
return 1;
CONFIG_TASK_SCHED_INFO?
It makes it equal to constant 1, because all its callers are
under #ifdef CONFIG_TASK_SCHED_INFO =)
its current code:
static inline int sched_info_on(void)
{
#ifdef CONFIG_SCHEDSTATS
return 1;
#elif defined(CONFIG_TASK_DELAY_ACCT)
extern int delayacct_on;
return delayacct_on;
#else
return 0;
#endif
}
CONFIG_SCHEDSTATS == debug option in lib/Kconfig.debug for /proc/schedstat
CONFIG_TASK_DELAY_ACCT == wierd net-link based statistics collecting tool
Thus, may be better to remove this function, because it can return 0
only if delay-accounting is compiled but disabled by boot option
(delayacct_on =1 by default since 2.6.18)
patch follows...
--
To unsubscribe from this list: send the line unsubscribe kvm in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v2] kvm: remove dependence on delay-accounting
Peter Zijlstra wrote:
On Sat, 2012-01-14 at 20:30 +0400, Konstantin Khlebnikov wrote:
KVM selects delay-accounting only to get sched-info for steal-time accounting.
Meanwhile delay-accounting can be disabled by boot option. This is ridiculous.
This patch adds internal boolean option CONFIG_TASK_SCHED_INFO to enable only
task-sched_info and its collecting inside scheduler.
Urgh, more stupid config knobs, we should be removing them, not adding
moar.
Unfortunately, removing task-delay-accounting is not the option =)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 868cb83..dd5bf78 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -734,7 +734,6 @@ extern struct user_struct root_user;
struct backing_dev_info;
-#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
struct sched_info {
/* cumulative counters */
unsigned long pcount; /* # of times run on this cpu */
@@ -744,7 +743,6 @@ struct sched_info {
unsigned long long last_arrival,/* when we last ran on a cpu */
last_queued; /* when we were last queued to run */
};
-#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
Not having that structure helps with compile errors.
I don't think so, this only helps to catch useless declarations and definitions
in code and inside other structures.
#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info {
@@ -782,7 +780,7 @@ struct task_delay_info {
static inline int sched_info_on(void)
{
-#ifdef CONFIG_SCHEDSTATS
+#if IS_ENABLED(CONFIG_SCHEDSTATS) || IS_ENABLED(CONFIG_KVM)
WTF is IS_ENABLED and why do you use it?
IS_ENABLED(smth) == (defined(smth) || defined(smth_MODULE))
but using it for CONFIG_SCHEDSTATS is overkill, indeed.
Not much like this stuff.
--
To unsubscribe from this list: send the line unsubscribe kvm in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
