Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Mon, Jan 16, 2017 at 01:57:25AM +, Zheng, Lv wrote: > Hi, > > > From: Borislav Petkov [mailto:b...@alien8.de] > > Subject: Re: [PATCH] rcu: Narrow early boot window of illegal synchronous > > grace periods > > > > On Sat, Jan 14, 2017 at 01:27

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Mon, Jan 16, 2017 at 01:57:25AM +, Zheng, Lv wrote: > Hi, > > > From: Borislav Petkov [mailto:b...@alien8.de] > > Subject: Re: [PATCH] rcu: Narrow early boot window of illegal synchronous > > grace periods > > > > On Sat, Jan 14, 2017 at 01:27

RE: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

Hi, > From: Borislav Petkov [mailto:b...@alien8.de] > Subject: Re: [PATCH] rcu: Narrow early boot window of illegal synchronous > grace periods > > On Sat, Jan 14, 2017 at 01:27:40PM +0100, Rafael J. Wysocki wrote: > > OK, so this fixes the problem with sync

RE: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

Hi, > From: Borislav Petkov [mailto:b...@alien8.de] > Subject: Re: [PATCH] rcu: Narrow early boot window of illegal synchronous > grace periods > > On Sat, Jan 14, 2017 at 01:27:40PM +0100, Rafael J. Wysocki wrote: > > OK, so this fixes the problem with sync

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sun, Jan 15, 2017 at 11:09:31AM +0100, Borislav Petkov wrote: > On Sat, Jan 14, 2017 at 09:24:43PM -0800, Paul E. McKenney wrote: > > > Which means, you probably should tag your fix CC:stable and add > > > > > > Fixes: 8b355e3bc140 ("rcu: Drive expedited grace periods from workqueue") > > > >

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sun, Jan 15, 2017 at 11:09:31AM +0100, Borislav Petkov wrote: > On Sat, Jan 14, 2017 at 09:24:43PM -0800, Paul E. McKenney wrote: > > > Which means, you probably should tag your fix CC:stable and add > > > > > > Fixes: 8b355e3bc140 ("rcu: Drive expedited grace periods from workqueue") > > > >

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 09:24:43PM -0800, Paul E. McKenney wrote: > > Which means, you probably should tag your fix CC:stable and add > > > > Fixes: 8b355e3bc140 ("rcu: Drive expedited grace periods from workqueue") > > > > to it too. > > Like this? Very nice, ship it! :-) Thanks. --

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 09:24:43PM -0800, Paul E. McKenney wrote: > > Which means, you probably should tag your fix CC:stable and add > > > > Fixes: 8b355e3bc140 ("rcu: Drive expedited grace periods from workqueue") > > > > to it too. > > Like this? Very nice, ship it! :-) Thanks. --

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 11:35:25AM +0100, Borislav Petkov wrote: > On Sat, Jan 14, 2017 at 12:00:22AM -0800, Paul E. McKenney wrote: > > It now looks like this: > > > > > > > > Note that the code was buggy even before this

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 11:35:25AM +0100, Borislav Petkov wrote: > On Sat, Jan 14, 2017 at 12:00:22AM -0800, Paul E. McKenney wrote: > > It now looks like this: > > > > > > > > Note that the code was buggy even before this

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 01:27:40PM +0100, Rafael J. Wysocki wrote: > OK, so this fixes the problem with synchronize_rcu_expedited() in > acpi_os_map_cleanup(), right? Yeah. > I wonder if the ACPI-specific fix is still needed, then? It is not strictly necessary. If you still think it would be

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 01:27:40PM +0100, Rafael J. Wysocki wrote: > OK, so this fixes the problem with synchronize_rcu_expedited() in > acpi_os_map_cleanup(), right? Yeah. > I wonder if the ACPI-specific fix is still needed, then? It is not strictly necessary. If you still think it would be

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 11:35 AM, Borislav Petkov wrote: > On Sat, Jan 14, 2017 at 12:00:22AM -0800, Paul E. McKenney wrote: >> It now looks like this: >> >> >> >> Note that the code was buggy even before

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 11:35 AM, Borislav Petkov wrote: > On Sat, Jan 14, 2017 at 12:00:22AM -0800, Paul E. McKenney wrote: >> It now looks like this: >> >> >> >> Note that the code was buggy even before this commit, as it

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 12:00:22AM -0800, Paul E. McKenney wrote: > It now looks like this: > > > > Note that the code was buggy even before this commit, as it was subject > to failure on real-time systems that forced all

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Sat, Jan 14, 2017 at 12:00:22AM -0800, Paul E. McKenney wrote: > It now looks like this: > > > > Note that the code was buggy even before this commit, as it was subject > to failure on real-time systems that forced all

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Fri, Jan 13, 2017 at 12:25:19PM +0100, Borislav Petkov wrote: > On Thu, Jan 12, 2017 at 06:38:07PM -0800, Paul E. McKenney wrote: > > The current preemptible RCU implementation goes through three phases > > during bootup. In the first phase, there is only one CPU that is running > > with

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Fri, Jan 13, 2017 at 12:25:19PM +0100, Borislav Petkov wrote: > On Thu, Jan 12, 2017 at 06:38:07PM -0800, Paul E. McKenney wrote: > > The current preemptible RCU implementation goes through three phases > > during bootup. In the first phase, there is only one CPU that is running > > with

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Thu, Jan 12, 2017 at 06:38:07PM -0800, Paul E. McKenney wrote: > The current preemptible RCU implementation goes through three phases > during bootup. In the first phase, there is only one CPU that is running > with preemption disabled, so that a no-op is a synchronous grace period. > In the

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Thu, Jan 12, 2017 at 06:38:07PM -0800, Paul E. McKenney wrote: > The current preemptible RCU implementation goes through three phases > during bootup. In the first phase, there is only one CPU that is running > with preemption disabled, so that a no-op is a synchronous grace period. > In the

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Thu, Jan 12, 2017 at 06:38:07PM -0800, Paul E. McKenney wrote: > The current preemptible RCU implementation goes through three phases > during bootup. In the first phase, there is only one CPU that is running > with preemption disabled, so that a no-op is a synchronous grace period. > In the

Re: [PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

On Thu, Jan 12, 2017 at 06:38:07PM -0800, Paul E. McKenney wrote: > The current preemptible RCU implementation goes through three phases > during bootup. In the first phase, there is only one CPU that is running > with preemption disabled, so that a no-op is a synchronous grace period. > In the

[PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

The current preemptible RCU implementation goes through three phases during bootup. In the first phase, there is only one CPU that is running with preemption disabled, so that a no-op is a synchronous grace period. In the second mid-boot phase, the scheduler is running, but RCU has not yet gotten

[PATCH] rcu: Narrow early boot window of illegal synchronous grace periods

The current preemptible RCU implementation goes through three phases during bootup. In the first phase, there is only one CPU that is running with preemption disabled, so that a no-op is a synchronous grace period. In the second mid-boot phase, the scheduler is running, but RCU has not yet gotten