Re: [RFA][PATCH 25/27] arm64, ftrace: Remove check of obsolete variable function_trace_stop
On 06/27/2014 09:44 PM, Will Deacon wrote: Hi Steve, On Thu, Jun 26, 2014 at 05:52:46PM +0100, Steven Rostedt wrote: From: "Steven Rostedt (Red Hat)" Nothing sets function_trace_stop to disable function tracing anymore. Remove the check for it in the arch code. arm64 was broken anyway, as it had an ifdef testing CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST which is only set if the arch supports the code (which it obviously did not), and it was testing a non existent ftrace_trace_stop instead of function_trace_stop. Yeah, the current code is total crap. Well spotted. Thank you for fixing my bug :) I also exercised ftrace with sysfs interface, and it just works well. -Takahiro AKASHI Cc: AKASHI Takahiro Cc: Will Deacon Signed-off-by: Steven Rostedt --- arch/arm64/kernel/entry-ftrace.S | 5 - 1 file changed, 5 deletions(-) Acked-by: Will Deacon I'm happy for you to take this via the ftrace tree, along with the rest of the series. I successfully ran the ftrace self tests with this applied (on top of "ftrace: Remove check for HAVE_FUNCTION_TRACE_MCOUNT_TEST"), but note that I don't have a platform with working suspend/resume right now. Cheers, Will diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S index b051871f2965..1b1e330e6849 100644 --- a/arch/arm64/kernel/entry-ftrace.S +++ b/arch/arm64/kernel/entry-ftrace.S @@ -96,11 +96,6 @@ * - ftrace_graph_caller to set up an exit hook */ ENTRY(_mcount) -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ldr x0, =ftrace_trace_stop - ldr x0, [x0]// if ftrace_trace_stop - ret // return; -#endif mcount_enter ldr x0, =ftrace_trace_function -- 2.0.0 -- 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: [RFA][PATCH 25/27] arm64, ftrace: Remove check of obsolete variable function_trace_stop
Hi Steve, On Thu, Jun 26, 2014 at 05:52:46PM +0100, Steven Rostedt wrote: > From: "Steven Rostedt (Red Hat)" > > Nothing sets function_trace_stop to disable function tracing anymore. > Remove the check for it in the arch code. > > arm64 was broken anyway, as it had an ifdef testing > CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST which is only set if > the arch supports the code (which it obviously did not), and > it was testing a non existent ftrace_trace_stop instead of > function_trace_stop. Yeah, the current code is total crap. Well spotted. > Cc: AKASHI Takahiro > Cc: Will Deacon > Signed-off-by: Steven Rostedt > --- > arch/arm64/kernel/entry-ftrace.S | 5 - > 1 file changed, 5 deletions(-) Acked-by: Will Deacon I'm happy for you to take this via the ftrace tree, along with the rest of the series. I successfully ran the ftrace self tests with this applied (on top of "ftrace: Remove check for HAVE_FUNCTION_TRACE_MCOUNT_TEST"), but note that I don't have a platform with working suspend/resume right now. Cheers, Will > diff --git a/arch/arm64/kernel/entry-ftrace.S > b/arch/arm64/kernel/entry-ftrace.S > index b051871f2965..1b1e330e6849 100644 > --- a/arch/arm64/kernel/entry-ftrace.S > +++ b/arch/arm64/kernel/entry-ftrace.S > @@ -96,11 +96,6 @@ > * - ftrace_graph_caller to set up an exit hook > */ > ENTRY(_mcount) > -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST > - ldr x0, =ftrace_trace_stop > - ldr x0, [x0]// if ftrace_trace_stop > - ret // return; > -#endif > mcount_enter > > ldr x0, =ftrace_trace_function > -- > 2.0.0 > > > -- 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: [RFA][PATCH 25/27] arm64, ftrace: Remove check of obsolete variable function_trace_stop
On Thu, 26 Jun 2014 12:52:46 -0400 Steven Rostedt wrote: > From: "Steven Rostedt (Red Hat)" > > Nothing sets function_trace_stop to disable function tracing anymore. > Remove the check for it in the arch code. > > arm64 was broken anyway, as it had an ifdef testing > CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST which is only set if > the arch supports the code (which it obviously did not), and > it was testing a non existent ftrace_trace_stop instead of > function_trace_stop. >From the cover letter, you were not Cc'd on. Anyway, as there is no more reason to set function_trace_stop it is time to remove it. Unfortunately it's in several archs in assembly. Most of the assembly looks rather straight forward and I removed them myself. But I was only able to compile test them (for archs: arm64, metag, and microblaze I do not have my cross tools set up for them and did not even compile test it). But I would really love it if people can download their patch and test it out. You only need the patches that go against your arch and to really test it, also include the patch titled: ftrace: Remove check for HAVE_FUNCTION_TRACE_MCOUNT_TEST Otherwise your arch patch will call the list op that still does the check. That is, if you want to test suspend and resume on your arch. As you may see, there are patches to the ftrace infrastructure that depend on the arch patches being implemented. I removed the functionality from the infrastructure, then removed it from the archs, and then finally removed the existence of the function_trace_stop variable, which would cause the archs to fail to compile if that were to go first. If you can test your arch and give me your acked-by, I would appreciate it. Otherwise, if you need this to go through your tree, I would ask you to set up a dedicated branch that I can pull from to keep this order intact. -- Steve > > Cc: AKASHI Takahiro > Cc: Will Deacon > Signed-off-by: Steven Rostedt > --- > arch/arm64/kernel/entry-ftrace.S | 5 - > 1 file changed, 5 deletions(-) > > diff --git a/arch/arm64/kernel/entry-ftrace.S > b/arch/arm64/kernel/entry-ftrace.S > index b051871f2965..1b1e330e6849 100644 > --- a/arch/arm64/kernel/entry-ftrace.S > +++ b/arch/arm64/kernel/entry-ftrace.S > @@ -96,11 +96,6 @@ > * - ftrace_graph_caller to set up an exit hook > */ > ENTRY(_mcount) > -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST > - ldr x0, =ftrace_trace_stop > - ldr x0, [x0]// if ftrace_trace_stop > - ret // return; > -#endif > mcount_enter > > ldr x0, =ftrace_trace_function -- 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/
[RFA][PATCH 25/27] arm64, ftrace: Remove check of obsolete variable function_trace_stop
From: "Steven Rostedt (Red Hat)" Nothing sets function_trace_stop to disable function tracing anymore. Remove the check for it in the arch code. arm64 was broken anyway, as it had an ifdef testing CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST which is only set if the arch supports the code (which it obviously did not), and it was testing a non existent ftrace_trace_stop instead of function_trace_stop. Cc: AKASHI Takahiro Cc: Will Deacon Signed-off-by: Steven Rostedt --- arch/arm64/kernel/entry-ftrace.S | 5 - 1 file changed, 5 deletions(-) diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S index b051871f2965..1b1e330e6849 100644 --- a/arch/arm64/kernel/entry-ftrace.S +++ b/arch/arm64/kernel/entry-ftrace.S @@ -96,11 +96,6 @@ * - ftrace_graph_caller to set up an exit hook */ ENTRY(_mcount) -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ldr x0, =ftrace_trace_stop - ldr x0, [x0]// if ftrace_trace_stop - ret // return; -#endif mcount_enter ldr x0, =ftrace_trace_function -- 2.0.0 -- 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/
