Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-20 Thread Christoph Lameter
On Tue, 18 Mar 2014, Andrew Morton wrote: > > snprintf can cause hangs. > > This is weird. How the heck can snprintf() fail if called too early? > All it does is shuffle chars around in memory. The only external > dependency I'm seeing is a WARN_ON() which presumably didn't trigger > anyway. >

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-20 Thread Christoph Lameter
On Tue, 18 Mar 2014, Andrew Morton wrote: snprintf can cause hangs. This is weird. How the heck can snprintf() fail if called too early? All it does is shuffle chars around in memory. The only external dependency I'm seeing is a WARN_ON() which presumably didn't trigger anyway. I'm

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-19 Thread Grygorii Strashko
On 03/18/2014 11:37 PM, Andrew Morton wrote:> On Tue, 18 Mar 2014 10:54:06 -0500 (CDT) Christoph Lameter wrote: > >> On Tue, 18 Mar 2014, Grygorii Strashko wrote: >> >>> Any way, I can boot and console works fine with your change :) >>> Thanks. >> >> Ok here is the properly formatted patch: >>

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-19 Thread Grygorii Strashko
On 03/18/2014 11:37 PM, Andrew Morton wrote: On Tue, 18 Mar 2014 10:54:06 -0500 (CDT) Christoph Lameter c...@linux.com wrote: On Tue, 18 Mar 2014, Grygorii Strashko wrote: Any way, I can boot and console works fine with your change :) Thanks. Ok here is the properly formatted patch:

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Andrew Morton
On Tue, 18 Mar 2014 10:54:06 -0500 (CDT) Christoph Lameter wrote: > On Tue, 18 Mar 2014, Grygorii Strashko wrote: > > > Any way, I can boot and console works fine with your change :) > > Thanks. > > Ok here is the properly formatted patch: > > > Subject: preemption_checks: Avoid snprintf

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Christoph Lameter
On Tue, 18 Mar 2014, Grygorii Strashko wrote: > Any way, I can boot and console works fine with your change :) > Thanks. Ok here is the properly formatted patch: Subject: preemption_checks: Avoid snprintf before checking error conditions snprintf can cause hangs. Move the string processing

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Grygorii Strashko
On 03/18/2014 04:37 PM, Christoph Lameter wrote: On Tue, 18 Mar 2014, Grygorii Strashko wrote: diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c index a270dce..73a2004 100644 --- a/lib/smp_processor_id.c +++ b/lib/smp_processor_id.c @@ -58,9 +58,6 @@

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Christoph Lameter
On Tue, 18 Mar 2014, Grygorii Strashko wrote: > diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c > index a270dce..73a2004 100644 > --- a/lib/smp_processor_id.c > +++ b/lib/smp_processor_id.c > @@ -58,9 +58,6 @@ EXPORT_SYMBOL(debug_smp_processor_id); > > notrace void

[linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Grygorii Strashko
Hi All, The regression is observed in the current linux-next on ARM Keystone 2 SoC: - system is booted till console and in a second or two and then stall, no messages displayed (CONFIG_DEBUG_PREEMPT=y). The cause of regression has been bisected to the commit: commit

[linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Grygorii Strashko
Hi All, The regression is observed in the current linux-next on ARM Keystone 2 SoC: - system is booted till console and in a second or two and then stall, no messages displayed (CONFIG_DEBUG_PREEMPT=y). The cause of regression has been bisected to the commit: commit

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Christoph Lameter
On Tue, 18 Mar 2014, Grygorii Strashko wrote: diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c index a270dce..73a2004 100644 --- a/lib/smp_processor_id.c +++ b/lib/smp_processor_id.c @@ -58,9 +58,6 @@ EXPORT_SYMBOL(debug_smp_processor_id); notrace void

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Grygorii Strashko
On 03/18/2014 04:37 PM, Christoph Lameter wrote: On Tue, 18 Mar 2014, Grygorii Strashko wrote: diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c index a270dce..73a2004 100644 --- a/lib/smp_processor_id.c +++ b/lib/smp_processor_id.c @@ -58,9 +58,6 @@

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Christoph Lameter
On Tue, 18 Mar 2014, Grygorii Strashko wrote: Any way, I can boot and console works fine with your change :) Thanks. Ok here is the properly formatted patch: Subject: preemption_checks: Avoid snprintf before checking error conditions snprintf can cause hangs. Move the string processing into

Re: [linux-next][regression] [PATCH] percpu: add preemption checks to __this_cpu ops

2014-03-18 Thread Andrew Morton
On Tue, 18 Mar 2014 10:54:06 -0500 (CDT) Christoph Lameter c...@linux.com wrote: On Tue, 18 Mar 2014, Grygorii Strashko wrote: Any way, I can boot and console works fine with your change :) Thanks. Ok here is the properly formatted patch: Subject: preemption_checks: Avoid snprintf