Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-12-01 Thread Sergey Senozhatsky
On (12/01/16 14:36), Petr Mladek wrote: [..] > > > > > Note that the same code is newly used to flush also the printk_safe > > > > > per-CPU buffers. It means that logbuf_lock is zapped also when > > > > > flushing these new buffers. > > > > > > > > > > > > > Note that (raw_)spin_lock_init() as d

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-12-01 Thread Petr Mladek
On Thu 2016-12-01 06:42:29, Peter Zijlstra wrote: > On Thu, Dec 01, 2016 at 11:34:42AM +0900, Sergey Senozhatsky wrote: > > On (11/25/16 16:17), Peter Zijlstra wrote: > > > On Fri, Nov 25, 2016 at 04:01:13PM +0100, Petr Mladek wrote: > > > > On Fri 2016-10-28 00:49:33, Sergey Senozhatsky wrote: > >

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-12-01 Thread Petr Mladek
On Thu 2016-12-01 21:50:45, Sergey Senozhatsky wrote: > On (11/25/16 16:01), Petr Mladek wrote: > [..] > > > apart from detecting and reporting printk recursions, that code also > > > used to zap_lockc() in case of panic. However, zap_locks() does not > > ^ > > > > s/zap_lock

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-12-01 Thread Sergey Senozhatsky
On (11/25/16 16:01), Petr Mladek wrote: [..] > > apart from detecting and reporting printk recursions, that code also > > used to zap_lockc() in case of panic. However, zap_locks() does not > ^ > > s/zap_lockc/zap_locks/ > > > look to be needed anymore: > > > > 1) Since c

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-11-30 Thread Peter Zijlstra
On Thu, Dec 01, 2016 at 11:34:42AM +0900, Sergey Senozhatsky wrote: > On (11/25/16 16:17), Peter Zijlstra wrote: > > On Fri, Nov 25, 2016 at 04:01:13PM +0100, Petr Mladek wrote: > > > On Fri 2016-10-28 00:49:33, Sergey Senozhatsky wrote: > > > > 2) Since commit cf9b1106c81c ("printk/nmi: flush NMI

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-11-30 Thread Sergey Senozhatsky
On (11/25/16 16:17), Peter Zijlstra wrote: > On Fri, Nov 25, 2016 at 04:01:13PM +0100, Petr Mladek wrote: > > On Fri 2016-10-28 00:49:33, Sergey Senozhatsky wrote: > > > 2) Since commit cf9b1106c81c ("printk/nmi: flush NMI messages on the > > >system panic") panic attempts to zap the `logbuf_lo

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-11-30 Thread Sergey Senozhatsky
On (11/25/16 16:01), Petr Mladek wrote: > On Fri 2016-10-28 00:49:33, Sergey Senozhatsky wrote: > > We use printk-safe now which makes printk-recursion detection code > > in vprintk_emit() is unreachable. The tricky thing here is that, > ^^ superfluous "is" > > > apart from detec

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-11-25 Thread Peter Zijlstra
On Fri, Nov 25, 2016 at 04:01:13PM +0100, Petr Mladek wrote: > On Fri 2016-10-28 00:49:33, Sergey Senozhatsky wrote: > > 2) Since commit cf9b1106c81c ("printk/nmi: flush NMI messages on the > >system panic") panic attempts to zap the `logbuf_lock' spin_lock to > >successfully flush nmi mess

Re: [RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-11-25 Thread Petr Mladek
On Fri 2016-10-28 00:49:33, Sergey Senozhatsky wrote: > We use printk-safe now which makes printk-recursion detection code > in vprintk_emit() is unreachable. The tricky thing here is that, ^^ superfluous "is" > apart from detecting and reporting printk recursions, that code al

[RFC][PATCHv4 6/6] printk: remove zap_locks() function

2016-10-27 Thread Sergey Senozhatsky
We use printk-safe now which makes printk-recursion detection code in vprintk_emit() is unreachable. The tricky thing here is that, apart from detecting and reporting printk recursions, that code also used to zap_lockc() in case of panic. However, zap_locks() does not look to be needed anymore: 1)