Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-12 Thread Peter Zijlstra
On Thu, Aug 08, 2013 at 12:59:55PM -0500, Eric Boxer wrote: > Eric Boxer liked your message with Boxer. On Wed, Aug 07, 2013 at 07:36 PM, > Paul E. McKenney wrote: WTF kinda crap is this and can we stop this? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-08 Thread Paul E. McKenney
On Thu, Aug 08, 2013 at 01:27:55PM +0800, Lai Jiangshan wrote: > On 08/08/2013 12:18 PM, Paul E. McKenney wrote: > > On Thu, Aug 08, 2013 at 11:10:47AM +0800, Lai Jiangshan wrote: > >> On 08/08/2013 10:33 AM, Paul E. McKenney wrote: > >>> On Thu, Aug 08, 2013 at 10:33:15AM +0800, Lai Jiangshan wrot

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Lai Jiangshan
On 08/08/2013 12:18 PM, Paul E. McKenney wrote: > On Thu, Aug 08, 2013 at 11:10:47AM +0800, Lai Jiangshan wrote: >> On 08/08/2013 10:33 AM, Paul E. McKenney wrote: >>> On Thu, Aug 08, 2013 at 10:33:15AM +0800, Lai Jiangshan wrote: On 08/08/2013 10:12 AM, Steven Rostedt wrote: > On Thu, 201

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Paul E. McKenney
On Thu, Aug 08, 2013 at 11:10:47AM +0800, Lai Jiangshan wrote: > On 08/08/2013 10:33 AM, Paul E. McKenney wrote: > > On Thu, Aug 08, 2013 at 10:33:15AM +0800, Lai Jiangshan wrote: > >> On 08/08/2013 10:12 AM, Steven Rostedt wrote: > >>> On Thu, 2013-08-08 at 09:47 +0800, Lai Jiangshan wrote: > >>>

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Lai Jiangshan
On 08/08/2013 10:33 AM, Paul E. McKenney wrote: > On Thu, Aug 08, 2013 at 10:33:15AM +0800, Lai Jiangshan wrote: >> On 08/08/2013 10:12 AM, Steven Rostedt wrote: >>> On Thu, 2013-08-08 at 09:47 +0800, Lai Jiangshan wrote: >>> > [ 393.641012]CPU0 > [ 393.641012] > [

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Lai Jiangshan
On 08/08/2013 10:12 AM, Steven Rostedt wrote: > On Thu, 2013-08-08 at 09:47 +0800, Lai Jiangshan wrote: > >>> [ 393.641012]CPU0 >>> [ 393.641012] >>> [ 393.641012] lock(&lock->wait_lock); >>> [ 393.641012] >>> [ 393.641012] lock(&lock->wait_lock); >> >> Patch2 cau

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Paul E. McKenney
On Thu, Aug 08, 2013 at 10:33:15AM +0800, Lai Jiangshan wrote: > On 08/08/2013 10:12 AM, Steven Rostedt wrote: > > On Thu, 2013-08-08 at 09:47 +0800, Lai Jiangshan wrote: > > > >>> [ 393.641012]CPU0 > >>> [ 393.641012] > >>> [ 393.641012] lock(&lock->wait_lock); > >>> [ 3

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Lai Jiangshan
On 08/08/2013 10:12 AM, Steven Rostedt wrote: > On Thu, 2013-08-08 at 09:47 +0800, Lai Jiangshan wrote: > >>> [ 393.641012]CPU0 >>> [ 393.641012] >>> [ 393.641012] lock(&lock->wait_lock); >>> [ 393.641012] >>> [ 393.641012] lock(&lock->wait_lock); >> >> Patch2 cau

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Steven Rostedt
On Thu, 2013-08-08 at 09:47 +0800, Lai Jiangshan wrote: > > [ 393.641012]CPU0 > > [ 393.641012] > > [ 393.641012] lock(&lock->wait_lock); > > [ 393.641012] > > [ 393.641012] lock(&lock->wait_lock); > > Patch2 causes it! > When I found all lock which can (chained)

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Lai Jiangshan
On 08/08/2013 08:36 AM, Paul E. McKenney wrote: > On Wed, Aug 07, 2013 at 05:38:27AM -0700, Paul E. McKenney wrote: >> On Wed, Aug 07, 2013 at 06:24:56PM +0800, Lai Jiangshan wrote: >>> Although all articles declare that rcu read site is deadlock-immunity. >>> It is not true for rcu-preempt, it wil

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Lai Jiangshan
On 08/08/2013 03:29 AM, Carsten Emde wrote: > Hi Paul, > >>> Although all articles declare that rcu read site is deadlock-immunity. >>> It is not true for rcu-preempt, it will be deadlock if rcu read site >>> overlaps with scheduler lock. >> >> The real rule is that if the scheduler does its outer

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Carsten Emde
Hi Paul, Although all articles declare that rcu read site is deadlock-immunity. It is not true for rcu-preempt, it will be deadlock if rcu read site overlaps with scheduler lock. The real rule is that if the scheduler does its outermost rcu_read_unlock() with one of those locks held, it has to

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Paul E. McKenney
On Wed, Aug 07, 2013 at 09:29:07PM +0200, Carsten Emde wrote: > Hi Paul, > > >>Although all articles declare that rcu read site is deadlock-immunity. > >>It is not true for rcu-preempt, it will be deadlock if rcu read site > >>overlaps with scheduler lock. > > > >The real rule is that if the sched

Re: [PATCH 0/8] rcu: Ensure rcu read site is deadlock-immunity

2013-08-07 Thread Paul E. McKenney
On Wed, Aug 07, 2013 at 06:24:56PM +0800, Lai Jiangshan wrote: > Although all articles declare that rcu read site is deadlock-immunity. > It is not true for rcu-preempt, it will be deadlock if rcu read site > overlaps with scheduler lock. The real rule is that if the scheduler does its outermost r