Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423250Ab3CWBbQ (ORCPT ); Fri, 22 Mar 2013 21:31:16 -0400 Received: from mga09.intel.com ([134.134.136.24]:55320 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422839Ab3CWBZq (ORCPT ); Fri, 22 Mar 2013 21:25:46 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,896,1355126400"; d="scan'208";a="306338475" From: Andi Kleen To: linux-kernel@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, x86@kernel.org, Andi Kleen Subject: [PATCH 12/29] x86, tsx: Add a per thread transaction disable count Date: Fri, 22 Mar 2013 18:25:06 -0700 Message-Id: <1364001923-10796-13-git-send-email-andi@firstfloor.org> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <1364001923-10796-1-git-send-email-andi@firstfloor.org> References: <1364001923-10796-1-git-send-email-andi@firstfloor.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1684 Lines: 54 From: Andi Kleen For some locks that have a low chance of not aborting it's best to just disable transactions. Add a counter to thread_info to allow to disable tranasctions for the current task. I originally experimented with more complicated solutions, like a magic spinlock type to disable with magic type matching, but that was very intrusive in the locking code. This setup -- while adding a few more instructions -- is more flexible and seems to work quite nicely. Signed-off-by: Andi Kleen --- arch/x86/include/asm/thread_info.h | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 2cd056e..91bb84e 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -39,6 +39,7 @@ struct thread_info { */ __u8 supervisor_stack[0]; #endif + unsigned notxn; /* transactions are disabled */ unsigned int sig_on_uaccess_error:1; unsigned int uaccess_err:1; /* uaccess failed */ }; @@ -279,6 +280,13 @@ static inline bool is_ia32_task(void) #endif return false; } + +#ifdef CONFIG_RTM_LOCKS +#define txn_disabled() (current_thread_info()->notxn) +#define disable_txn() (current_thread_info()->notxn++) +#define reenable_txn() (current_thread_info()->notxn--) +#endif + #endif /* !__ASSEMBLY__ */ #ifndef __ASSEMBLY__ -- 1.7.7.6 -- 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/