x86,pat Convert memtype_lock into an rw_lock.
in [Kernel]
|
Prev: [PATCH 2/3] staging wlan-ng: fix p80211wext_mhz_to_channel for channel 14
Next: [PATCH] x86, UV: Delete unneeded boot messages
From: Suresh Siddha on 17 Mar 2010 11:30 On Mon, 2010-03-15 at 06:21 -0700, holt(a)sgi.com wrote: > Convert the memtype_lock from a spin_lock to an rw_lock. The first > version of my patch had this and it did improve performance for fault > in times. The atomic page flags patch (first in the series) improves > things much greater for ram pages. This patch is to help the other pages. > Acked-by: Suresh Siddha <suresh.b.siddha(a)intel.com> X86 folks, can you please queue both these patches if you don't have any objections. thanks, suresh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: H. Peter Anvin on 17 Mar 2010 16:00 Well, as you know :) tglx and I are on the road ... I'll try to get to it on Friday before I take off again. "Suresh Siddha" <suresh.b.siddha(a)intel.com> wrote: >On Mon, 2010-03-15 at 06:21 -0700, holt(a)sgi.com wrote: >> Convert the memtype_lock from a spin_lock to an rw_lock. The first >> version of my patch had this and it did improve performance for fault >> in times. The atomic page flags patch (first in the series) improves >> things much greater for ram pages. This patch is to help the other pages. >> > >Acked-by: Suresh Siddha <suresh.b.siddha(a)intel.com> > >X86 folks, can you please queue both these patches if you don't have >any objections. > >thanks, >suresh > -- Sent from my mobile phone, pardon any lack of formatting.
From: Suresh Siddha on 17 Mar 2010 19:30 On Wed, 2010-03-17 at 12:51 -0700, H. Peter Anvin wrote: > Well, as you know :) tglx and I are on the road ... I'll try to get to it on Friday before I take off again. Also I talked to Thomas about this rwlock conversion and he referred to RT issues with rwlock. And the best is to avoid this using RCU. For now, the second patch can be perhaps dropped, as we are being proactive anyways. We can revisit this in the future. First patch "[patch 1/2] x86,pat Update the page flags for memtype atomically instead of using memtype_lock. -V3" is good to go. thanks, suresh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Peter Zijlstra on 24 Mar 2010 07:40 On Wed, 2010-03-17 at 16:19 -0800, Suresh Siddha wrote: > On Wed, 2010-03-17 at 12:51 -0700, H. Peter Anvin wrote: > > Well, as you know :) tglx and I are on the road ... I'll try to get to it on Friday before I take off again. > > Also I talked to Thomas about this rwlock conversion and he referred to > RT issues with rwlock. And the best is to avoid this using RCU. Its not just RT, even for mainline rwlock_t is a massive pain and often is no better (actually worse) than a spinlock due to the massive cacheline bouncing it introduces. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Suresh Siddha on 24 Mar 2010 12:20
On Wed, 2010-03-24 at 04:32 -0700, Peter Zijlstra wrote: > On Wed, 2010-03-17 at 16:19 -0800, Suresh Siddha wrote: > > On Wed, 2010-03-17 at 12:51 -0700, H. Peter Anvin wrote: > > > Well, as you know :) tglx and I are on the road ... I'll try to get to it on Friday before I take off again. > > > > Also I talked to Thomas about this rwlock conversion and he referred to > > RT issues with rwlock. And the best is to avoid this using RCU. > > Its not just RT, even for mainline rwlock_t is a massive pain and often > is no better (actually worse) than a spinlock due to the massive > cacheline bouncing it introduces. Don't we have the same cacheline bouncing issues with the ticket spinlocks? thanks, suresh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |