Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754738AbbFKOH6 (ORCPT ); Thu, 11 Jun 2015 10:07:58 -0400 Received: from mail-wi0-f174.google.com ([209.85.212.174]:36006 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932088AbbFKOHs (ORCPT ); Thu, 11 Jun 2015 10:07:48 -0400 From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: linux-mml@vger.kernel.org, Andy Lutomirski , Andrew Morton , Denys Vlasenko , Brian Gerst , Peter Zijlstra , Borislav Petkov , "H. Peter Anvin" , Linus Torvalds , Oleg Nesterov , Thomas Gleixner , Waiman Long Subject: [PATCH 08/12] x86/mm: Remove pgd_list use from vmalloc_sync_all() Date: Thu, 11 Jun 2015 16:07:13 +0200 Message-Id: <1434031637-9091-9-git-send-email-mingo@kernel.org> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1434031637-9091-1-git-send-email-mingo@kernel.org> References: <1434031637-9091-1-git-send-email-mingo@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2700 Lines: 93 The vmalloc() code uses vmalloc_sync_all() to synchronize changes to the global reference kernel PGD to task PGDs. This uses pgd_list currently, but we don't need the global list, as we can walk the task list under RCU. Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Waiman Long Cc: linux-mm@vger.kernel.org Signed-off-by: Ingo Molnar --- arch/x86/mm/fault.c | 21 ++++++++++++++------- arch/x86/mm/init_64.c | 3 ++- 2 files changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 50342825f221..2d587e548b59 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -235,24 +235,31 @@ void vmalloc_sync_all(void) for (address = VMALLOC_START & PMD_MASK; address >= TASK_SIZE && address < FIXADDR_TOP; address += PMD_SIZE) { - struct page *page; + struct task_struct *g, *p; + + rcu_read_lock(); spin_lock(&pgd_lock); - list_for_each_entry(page, &pgd_list, lru) { + + for_each_process_thread(g, p) { spinlock_t *pgt_lock; - pmd_t *ret; + pmd_t *pmd_ret; - /* the pgt_lock only for Xen */ - pgt_lock = &pgd_page_get_mm(page)->page_table_lock; + if (!p->mm) + continue; + /* The pgt_lock is only used on Xen: */ + pgt_lock = &p->mm->page_table_lock; spin_lock(pgt_lock); - ret = vmalloc_sync_one(page_address(page), address); + pmd_ret = vmalloc_sync_one(p->mm->pgd, address); spin_unlock(pgt_lock); - if (!ret) + if (!pmd_ret) break; } + spin_unlock(&pgd_lock); + rcu_read_unlock(); } } diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index beee532b76a7..730560c4873e 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -184,11 +184,12 @@ void sync_global_pgds(unsigned long start, unsigned long end) spin_lock(&pgd_lock); for_each_process_thread(g, p) { - pgd_t *pgd = p->mm->pgd; + pgd_t *pgd; spinlock_t *pgt_lock; if (!p->mm) continue; + pgd = p->mm->pgd; /* The pgt_lock is only used by Xen: */ pgt_lock = &p->mm->page_table_lock; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/