From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751239Ab2KOWep (ORCPT ); Thu, 15 Nov 2012 17:34:45 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:45779 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750712Ab2KOWeo (ORCPT ); Thu, 15 Nov 2012 17:34:44 -0500 Date: Thu, 15 Nov 2012 14:34:42 -0800 From: Andrew Morton To: KY Srinivasan Cc: Greg KH , "linux-kernel@vger.kernel.org" , "devel@linuxdriverproject.org" Subject: Re: drivres/hv Message-Id: <20121115143442.fd3672b8.akpm@linux-foundation.org> In-Reply-To: <426367E2313C2449837CD2DE46E7EAF930E47FEC@SN2PRD0310MB382.namprd03.prod.outlook.com> References: <1351894283-12902-1-git-send-email-kys@microsoft.com> <20121102233717.GB3239@kroah.com> <426367E2313C2449837CD2DE46E7EAF930E47FEC@SN2PRD0310MB382.namprd03.prod.outlook.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 15 Nov 2012 22:22:06 +0000 KY Srinivasan wrote: > > > > -----Original Message----- > > From: Greg KH [mailto:gregkh@linuxfoundation.org] > > Sent: Friday, November 02, 2012 7:37 PM > > To: KY Srinivasan > > Cc: linux-kernel@vger.kernel.org; devel@linuxdriverproject.org > > Subject: Re: drivres/hv > > > > On Fri, Nov 02, 2012 at 03:11:23PM -0700, K. Y. Srinivasan wrote: > > > > > > Greg, > > > > > > Recently, I had re-sent a few patches. You have applied all the patches except > > the balloon driver > > > related patches. Should I resend the balloon driver patches. Let me know. > > > > I can't apply the balloon driver until you get an ack from the > > maintainers of the code you were exporting the symbols from. > > > > Get that, and then resend them, as they are long gone from my "to-apply" > > queue. > > Greg, > > Andrew has checked in my patch that exports the necessary function for Hyper-V > balloon driver: > > commit bb2495a71b8499bdfe207738bc88ffa91ebe0b0a > Author: K. Y. Srinivasan > Date: Thu Nov 15 13:37:59 2012 +1100 > > I had sent the new balloon driver that used this new function a few days ago. Should I > resend the balloon driver. Let me know. I'll send this in to Linus later this week, to make life easier for everyone. Or Greg can grab it. From: "K. Y. Srinivasan" Subject: mm: export a function to get vm committed memory It will be useful to be able to access global memory commitment from device drivers. On the Hyper-V platform, the host has a policy engine to balance the available physical memory amongst all competing virtual machines hosted on a given node. This policy engine is driven by a number of metrics including the memory commitment reported by the guests. The balloon driver for Linux on Hyper-V will use this function to retrieve guest memory commitment. This function is also used in Xen self ballooning code. [akpm@linux-foundation.org: coding-style tweak] Signed-off-by: K. Y. Srinivasan Cc: Greg KH Acked-by: David Rientjes Acked-by: Dan Magenheimer Cc: Konrad Rzeszutek Wilk Cc: Jeremy Fitzhardinge Signed-off-by: Andrew Morton --- drivers/xen/xen-selfballoon.c | 2 +- include/linux/mman.h | 2 ++ mm/mmap.c | 14 ++++++++++++++ mm/nommu.c | 15 +++++++++++++++ 4 files changed, 32 insertions(+), 1 deletion(-) diff -puN drivers/xen/xen-selfballoon.c~mm-export-a-function-to-get-vm-committed-memory drivers/xen/xen-selfballoon.c --- a/drivers/xen/xen-selfballoon.c~mm-export-a-function-to-get-vm-committed-memory +++ a/drivers/xen/xen-selfballoon.c @@ -222,7 +222,7 @@ static void selfballoon_process(struct w if (xen_selfballooning_enabled) { cur_pages = totalram_pages; tgt_pages = cur_pages; /* default is no change */ - goal_pages = percpu_counter_read_positive(&vm_committed_as) + + goal_pages = vm_memory_committed() + totalreserve_pages + MB2PAGES(selfballoon_reserved_mb); #ifdef CONFIG_FRONTSWAP diff -puN include/linux/mman.h~mm-export-a-function-to-get-vm-committed-memory include/linux/mman.h --- a/include/linux/mman.h~mm-export-a-function-to-get-vm-committed-memory +++ a/include/linux/mman.h @@ -11,6 +11,8 @@ extern int sysctl_overcommit_memory; extern int sysctl_overcommit_ratio; extern struct percpu_counter vm_committed_as; +unsigned long vm_memory_committed(void); + static inline void vm_acct_memory(long pages) { percpu_counter_add(&vm_committed_as, pages); diff -puN mm/mmap.c~mm-export-a-function-to-get-vm-committed-memory mm/mmap.c --- a/mm/mmap.c~mm-export-a-function-to-get-vm-committed-memory +++ a/mm/mmap.c @@ -89,6 +89,20 @@ int sysctl_max_map_count __read_mostly = struct percpu_counter vm_committed_as ____cacheline_aligned_in_smp; /* + * The global memory commitment made in the system can be a metric + * that can be used to drive ballooning decisions when Linux is hosted + * as a guest. On Hyper-V, the host implements a policy engine for dynamically + * balancing memory across competing virtual machines that are hosted. + * Several metrics drive this policy engine including the guest reported + * memory commitment. + */ +unsigned long vm_memory_committed(void) +{ + return percpu_counter_read_positive(&vm_committed_as); +} +EXPORT_SYMBOL_GPL(vm_memory_committed); + +/* * Check that a process has enough memory to allocate a new virtual * mapping. 0 means there is enough memory for the allocation to * succeed and -ENOMEM implies there is not. diff -puN mm/nommu.c~mm-export-a-function-to-get-vm-committed-memory mm/nommu.c --- a/mm/nommu.c~mm-export-a-function-to-get-vm-committed-memory +++ a/mm/nommu.c @@ -66,6 +66,21 @@ int heap_stack_gap = 0; atomic_long_t mmap_pages_allocated; +/* + * The global memory commitment made in the system can be a metric + * that can be used to drive ballooning decisions when Linux is hosted + * as a guest. On Hyper-V, the host implements a policy engine for dynamically + * balancing memory across competing virtual machines that are hosted. + * Several metrics drive this policy engine including the guest reported + * memory commitment. + */ +unsigned long vm_memory_committed(void) +{ + return percpu_counter_read_positive(&vm_committed_as); +} + +EXPORT_SYMBOL_GPL(vm_memory_committed); + EXPORT_SYMBOL(mem_map); EXPORT_SYMBOL(num_physpages); _