Re: [PATCH] arm: Fix build error with context tracking calls
On Wed, Sep 25, 2013 at 10:38:58AM -0700, Kevin Hilman wrote: Frederic Weisbecker fweis...@gmail.com writes: 2013/9/14, Russell King - ARM Linux li...@arm.linux.org.uk: On Fri, Sep 13, 2013 at 07:03:34PM +0200, Frederic Weisbecker wrote: diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c index 247091b..859c8df 100644 --- a/kernel/context_tracking.c +++ b/kernel/context_tracking.c @@ -51,6 +51,15 @@ void context_tracking_user_enter(void) unsigned long flags; /* + * Repeat the user_enter() check here because some archs may be calling + * this from asm and if no CPU needs context tracking, they shouldn't + * go further. We can remove that check here once these archs support the static key + * check. The only (minor) comment on this is that the above would fail checkpatch, but that's not a good enough reason to respin it if you've already applied it IMHO. Ah I haven't yet pushed that patch anywhere so I can definetly fix that. Thanks for the review. BTW, I initially first thought this fix could go through your tree but if you prefer I can push it through Ingo to the context tracking bits. Just tell me either way. Frederic, I suggest you queue it directly for v3.12-rc. Thanks, Ok, I'm doing that then, thanks you! -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] arm: Fix build error with context tracking calls
2013/9/14, Russell King - ARM Linux li...@arm.linux.org.uk: On Fri, Sep 13, 2013 at 07:03:34PM +0200, Frederic Weisbecker wrote: diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c index 247091b..859c8df 100644 --- a/kernel/context_tracking.c +++ b/kernel/context_tracking.c @@ -51,6 +51,15 @@ void context_tracking_user_enter(void) unsigned long flags; /* + * Repeat the user_enter() check here because some archs may be calling + * this from asm and if no CPU needs context tracking, they shouldn't + * go further. We can remove that check here once these archs support the static key + * check. The only (minor) comment on this is that the above would fail checkpatch, but that's not a good enough reason to respin it if you've already applied it IMHO. Ah I haven't yet pushed that patch anywhere so I can definetly fix that. Thanks for the review. BTW, I initially first thought this fix could go through your tree but if you prefer I can push it through Ingo to the context tracking bits. Just tell me either way. Thanks! -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] arm: Fix build error with context tracking calls
On Fri, Sep 13, 2013 at 03:50:07PM -0700, Kevin Hilman wrote: Frederic Weisbecker fweis...@gmail.com writes: On Tue, Sep 10, 2013 at 08:07:45AM -0700, Kevin Hilman wrote: Nicolas Pitre nicolas.pi...@linaro.org writes: Adding Kevin Hilman to the CC as he might be interested as well. Thanks, I'd already noticed this but was distracted getting arm-soc changes ready for the merge window. Looking into it now. Kevin, can you please try this patch? It built tested fine on ARM and live tested correctly on x86. There should be no problem but just in case. Tested-by: Kevin Hilman khil...@linaro.org Things are back to working again on ARM. Thanks for the fix, and for build testing on ARM. As you noticed to test on ARM, we still have to carry that patch to drop that 'depends on 64BIT' in order to build/test this... any more thoughts on what the remaining obstacles there are? I was mostly fine with your last patchset that enabled that + a few stuff to make it working on ARM. There were just a few details to polish. But I remember I sent detailed reviews, may be you missed them somewhow? Thanks. -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH] arm: Fix build error with context tracking calls
On Tue, Sep 10, 2013 at 08:07:45AM -0700, Kevin Hilman wrote:
Nicolas Pitre nicolas.pi...@linaro.org writes:
Adding Kevin Hilman to the CC as he might be interested as well.
Thanks, I'd already noticed this but was distracted getting arm-soc
changes ready for the merge window. Looking into it now.
Kevin, can you please try this patch? It built tested fine on ARM
and live tested correctly on x86. There should be no problem but
just in case.
Thanks!
---
From 9bb601401baea0a2b2eead3909a9f186d894d617 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker fweis...@gmail.com
Date: Tue, 10 Sep 2013 00:54:17 +0200
Subject: [PATCH] arm: Fix build error with context tracking calls
ad65782fba50 (context_tracking: Optimize main APIs off case
with static key) converted context tracking main APIs to inline
functions and left ARM asm callers behind.
This can be easily fixed by making ARM calling the post static
keys context tracking functions. We just need to replicate the
static key checks there. We'll remove these later when ARM will
support the context tracking static keys.
Reported-by: Guenter Roeck li...@roeck-us.net
Reported-by: Russell King li...@arm.linux.org.uk
Signed-off-by: Frederic Weisbecker fweis...@gmail.com
Cc: Kevin Hilman khil...@linaro.org
Cc: Guenter Roeck li...@roeck-us.net
Cc: Nicolas Pitre nicolas.pi...@linaro.org
Cc: Anil Kumar anilk...@gmail.com
Cc: Tony Lindgren t...@atomide.com
Cc: Benoit Cousson b-cous...@ti.com
---
arch/arm/kernel/entry-header.S |8
kernel/context_tracking.c | 12
2 files changed, 16 insertions(+), 4 deletions(-)
diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
index de23a9b..39f89fb 100644
--- a/arch/arm/kernel/entry-header.S
+++ b/arch/arm/kernel/entry-header.S
@@ -329,10 +329,10 @@
#ifdef CONFIG_CONTEXT_TRACKING
.if \save
stmdb sp!, {r0-r3, ip, lr}
- bl user_exit
+ bl context_tracking_user_exit
ldmia sp!, {r0-r3, ip, lr}
.else
- bl user_exit
+ bl context_tracking_user_exit
.endif
#endif
.endm
@@ -341,10 +341,10 @@
#ifdef CONFIG_CONTEXT_TRACKING
.if \save
stmdb sp!, {r0-r3, ip, lr}
- bl user_enter
+ bl context_tracking_user_enter
ldmia sp!, {r0-r3, ip, lr}
.else
- bl user_enter
+ bl context_tracking_user_enter
.endif
#endif
.endm
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 247091b..859c8df 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -51,6 +51,15 @@ void context_tracking_user_enter(void)
unsigned long flags;
/*
+* Repeat the user_enter() check here because some archs may be calling
+* this from asm and if no CPU needs context tracking, they shouldn't
+* go further. We can remove that check here once these archs support
the static key
+* check.
+*/
+ if (!static_key_false(context_tracking_enabled))
+ return;
+
+ /*
* Some contexts may involve an exception occuring in an irq,
* leading to that nesting:
* rcu_irq_enter() rcu_user_exit() rcu_user_exit() rcu_irq_exit()
@@ -151,6 +160,9 @@ void context_tracking_user_exit(void)
{
unsigned long flags;
+ if (!static_key_false(context_tracking_enabled))
+ return;
+
if (in_interrupt())
return;
--
1.7.5.4
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Re: Build error in torvalds kernel 3.11 for omap2plus
On Tue, Sep 10, 2013 at 08:07:45AM -0700, Kevin Hilman wrote: Nicolas Pitre nicolas.pi...@linaro.org writes: Adding Kevin Hilman to the CC as he might be interested as well. Thanks, I'd already noticed this but was distracted getting arm-soc changes ready for the merge window. Looking into it now. I have the fix pending. It passed the cross build so I'll send it soon. Thanks. Kevin On Mon, 9 Sep 2013, Guenter Roeck wrote: On Mon, Sep 09, 2013 at 09:31:41PM +0100, Russell King - ARM Linux wrote: On Mon, Sep 09, 2013 at 09:03:48AM -0700, Guenter Roeck wrote: Unfortunately, there are more problems. arch/arm/kernel/built-in.o: In function `ret_fast_syscall': /home/groeck/src/linux-stable/arch/arm/kernel/entry-common.S:42: undefined reference to `user_enter' arch/arm/kernel/built-in.o: In function `no_work_pending': /home/groeck/src/linux-stable/arch/arm/kernel/entry-common.S:77: undefined reference to `user_enter' arch/arm/kernel/built-in.o: In function `vector_swi': /home/groeck/src/linux-stable/arch/arm/kernel/entry-common.S:376: undefined reference to `user_exit' arch/arm/kernel/built-in.o: In function `__dabt_usr': /home/groeck/src/linux-stable/arch/arm/kernel/entry-armv.S:365: undefined reference to `user_exit' arch/arm/kernel/built-in.o: In function `__irq_usr': /home/groeck/src/linux-stable/arch/arm/kernel/entry-armv.S:375: undefined reference to `user_exit' arch/arm/kernel/built-in.o: In function `__und_usr': /home/groeck/src/linux-stable/arch/arm/kernel/entry-armv.S:388: undefined reference to `user_exit' arch/arm/kernel/built-in.o: In function `__pabt_usr': /home/groeck/src/linux-stable/arch/arm/kernel/entry-armv.S:662: undefined reference to `user_exit' These are due to ad65782fba50 (context_tracking: Optimize main APIs off case with static key) converting these functions to be inline. No idea what the fix for this is other than reverting the change. Any ideas Frederic? I am all for reverting unless this can be fixed quickly. AFAICS this breaks all arm builds if CONFIG_CONTEXT_TRACKING is enabled. Guenter -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: rcu self-detected stall messages on OMAP3, 4 boards
2012/9/22 Paul E. McKenney paul...@linux.vnet.ibm.com: On Fri, Sep 21, 2012 at 01:31:49PM -0700, Tony Lindgren wrote: * Paul E. McKenney paul...@linux.vnet.ibm.com [120921 12:58]: Just to make sure I understand the combinations: o All stalls have happened when running a minimal userspace. o CONFIG_NO_HZ=n suppresses the stalls. o CONFIG_RCU_FAST_NO_HZ (which depends on CONFIG_NO_HZ=y) has no observable effect on the stalls. The reason why you may need minimal userspace is to cut down the number of timers waking up the system with NO_HZ. Booting with init=/bin/sh might also do the trick for that. Good point! This does make for a very quiet system, but does not reproduce the problem under kvm, even after waiting for four minutes. I will leave it for more time, but it looks like I really might need to ask Linaro for remote access to a Panda. I have one. I'm currently installing Ubuntu on it and I'll try to manage to build a kernel and reproduce the issue. I'll give more news soon. -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCH [0/4] perf: clean-up of power events API
On Thu, Oct 07, 2010 at 05:23:43PM +0200, Pierre Tardy wrote: On Thu, Oct 7, 2010 at 5:08 PM, Mathieu Desnoyers mathieu.desnoy...@efficios.com wrote: [ Adding a few more CCs, since this discussion is about a tracepoint userspace ABI policy, which is a topic of general interest. ] To add a little more comment, this is not the first time that tracepoints ABI changes. You can look at pytimechart sourcecode: http://gitorious.org/pytimechart/pytimechart/blobs/master/timechart/ftrace.py from 2.6.31 which is the first kernel I support, sched_switch: 'task %s:%d [%d] == %s:%d [%d]', changed to: sched_switch: 'prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s == next_comm=%s next_pid=%d next_prio=%d', workqueue_execution: 'thread=%s func=%s\\+%s/%s','thread','func','func_offset','func_size'), changed to: workqueue_execution: 'thread=%s func=%s','thread','func'), Seems to be only formatting changes, but no field has been removed and no tracepoint has been renamed, etc... So these are no stable ABI changes because the formatting can be changed anytime. We want that flexibility and it stands on top of the per event format files. Tools are not supposed to read ascii formatted traces from trace/trace_pipe files. Instead they need to read binary traces from trace_pipe_raw files and look at the format file to know how to format this. This is why we have these format files: to let tools adapt with changes like format change or fields added. And we have a library in perf and trace-cmd that let you - request a field value in a raw trace, by its name. So the field doesn't need to have a stable offset in the trace. - request ascii format info, so that if ascii format changes, the tool adapt. - record binary traces, much more leightweight for the writer (kernel) and for the reader (user). I did told you that it would be better you make PyTimeChart use the perf scripting facilities, it handles all the above things + it would avoid you to handle a lot of things. Now it's up to you, but don't count on us to make the ascii formatting a stable ABI. actually, over all the events pytimechart supports, only power traces are stable... Now one problem is that we have really broken the workqueue tracepoints in this release. I thought nobody was using them so we could refactor this tracepoint subsystem, my bad. workqueue_execution has become workqueue_execution_start and workqueue_execution_end. workqueue_insertion is going to suffer a similar split. workqueue_creation and workqueue_destruction have disappear but I can probably restore them, but for the rest, what should we do? I really feel uncomfortable with this tracepoint/ABI problem Mathieu suggested we start a user library that could handle these changes when they are really necessary. Thoughts? (Adding Tejun in Cc). -- To unsubscribe from this list: send the line unsubscribe linux-omap in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
