From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f200.google.com (mail-pf1-f200.google.com [209.85.210.200]) by kanga.kvack.org (Postfix) with ESMTP id 269A38E0002 for ; Mon, 14 Jan 2019 04:54:56 -0500 (EST) Received: by mail-pf1-f200.google.com with SMTP id 75so15730540pfq.8 for ; Mon, 14 Jan 2019 01:54:56 -0800 (PST) Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com. [148.163.156.1]) by mx.google.com with ESMTPS id t5si79223729pgc.369.2019.01.14.01.54.54 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 14 Jan 2019 01:54:54 -0800 (PST) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id x0E9mXuG088720 for ; Mon, 14 Jan 2019 04:54:54 -0500 Received: from e14.ny.us.ibm.com (e14.ny.us.ibm.com [129.33.205.204]) by mx0a-001b2d01.pphosted.com with ESMTP id 2q0ntt6jb3-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 14 Jan 2019 04:54:54 -0500 Received: from localhost by e14.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 14 Jan 2019 09:54:52 -0000 From: "Aneesh Kumar K.V" Subject: [PATCH V7 1/4] mm/cma: Add PF flag to force non cma alloc Date: Mon, 14 Jan 2019 15:24:33 +0530 In-Reply-To: <20190114095438.32470-1-aneesh.kumar@linux.ibm.com> References: <20190114095438.32470-1-aneesh.kumar@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-Id: <20190114095438.32470-2-aneesh.kumar@linux.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, Michal Hocko , Alexey Kardashevskiy , David Gibson , Andrea Arcangeli , mpe@ellerman.id.au Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, "Aneesh Kumar K.V" This patch adds PF_MEMALLOC_NOCMA which make sure any allocation in that context is marked non-movable and hence cannot be satisfied by CMA region. This is useful with get_user_pages_longterm where we want to take a page pin by migrating pages from CMA region. Marking the section PF_MEMALLOC_NOCMA ensures that we avoid unnecessary page migration later. Suggested-by: Andrea Arcangeli Reviewed-by: Andrea Arcangeli Signed-off-by: Aneesh Kumar K.V --- include/linux/sched.h | 1 + include/linux/sched/mm.h | 48 +++++++++++++++++++++++++++++++++------- 2 files changed, 41 insertions(+), 8 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 224666226e87..687b0edf97b2 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1406,6 +1406,7 @@ extern struct pid *cad_pid; #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ #define PF_MEMSTALL 0x01000000 /* Stalled due to lack of memory */ +#define PF_MEMALLOC_NOCMA 0x02000000 /* All allocation request will have _GFP_MOVABLE cleared */ #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 3bfa6a0cbba4..0cd9f10423fb 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -148,17 +148,25 @@ static inline bool in_vfork(struct task_struct *tsk) * Applies per-task gfp context to the given allocation flags. * PF_MEMALLOC_NOIO implies GFP_NOIO * PF_MEMALLOC_NOFS implies GFP_NOFS + * PF_MEMALLOC_NOCMA implies no allocation from CMA region. */ static inline gfp_t current_gfp_context(gfp_t flags) { - /* - * NOIO implies both NOIO and NOFS and it is a weaker context - * so always make sure it makes precedence - */ - if (unlikely(current->flags & PF_MEMALLOC_NOIO)) - flags &= ~(__GFP_IO | __GFP_FS); - else if (unlikely(current->flags & PF_MEMALLOC_NOFS)) - flags &= ~__GFP_FS; + if (unlikely(current->flags & + (PF_MEMALLOC_NOIO | PF_MEMALLOC_NOFS | PF_MEMALLOC_NOCMA))) { + /* + * NOIO implies both NOIO and NOFS and it is a weaker context + * so always make sure it makes precedence + */ + if (current->flags & PF_MEMALLOC_NOIO) + flags &= ~(__GFP_IO | __GFP_FS); + else if (current->flags & PF_MEMALLOC_NOFS) + flags &= ~__GFP_FS; +#ifdef CONFIG_CMA + if (current->flags & PF_MEMALLOC_NOCMA) + flags &= ~__GFP_MOVABLE; +#endif + } return flags; } @@ -248,6 +256,30 @@ static inline void memalloc_noreclaim_restore(unsigned int flags) current->flags = (current->flags & ~PF_MEMALLOC) | flags; } +#ifdef CONFIG_CMA +static inline unsigned int memalloc_nocma_save(void) +{ + unsigned int flags = current->flags & PF_MEMALLOC_NOCMA; + + current->flags |= PF_MEMALLOC_NOCMA; + return flags; +} + +static inline void memalloc_nocma_restore(unsigned int flags) +{ + current->flags = (current->flags & ~PF_MEMALLOC_NOCMA) | flags; +} +#else +static inline unsigned int memalloc_nocma_save(void) +{ + return 0; +} + +static inline void memalloc_nocma_restore(unsigned int flags) +{ +} +#endif + #ifdef CONFIG_MEMCG /** * memalloc_use_memcg - Starts the remote memcg charging scope. -- 2.20.1