From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Schmitz Subject: [PATCH 1/3] m68k/atari - convert atari_scsi falcon_get_lock() to use wait_event() Date: Sat, 1 Mar 2014 20:51:03 +1300 Message-ID: <1393660265-19384-2-git-send-email-schmitz@debian.org> References: <1393660265-19384-1-git-send-email-schmitz@debian.org> Return-path: Received: from mail-pa0-f41.google.com ([209.85.220.41]:55360 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752334AbaCAHvY (ORCPT ); Sat, 1 Mar 2014 02:51:24 -0500 In-Reply-To: <1393660265-19384-1-git-send-email-schmitz@debian.org> Sender: linux-m68k-owner@vger.kernel.org List-Id: linux-m68k@vger.kernel.org To: linux-m68k@vger.kernel.org Cc: geert@linux-m68k.org, JBottomley@parallels.com, linux-scsi@vger.kernel.org, arnd@arndb.de, Michael Schmitz sleep_on is known broken and going away. The atari_scsi driver is one of two remaining users in the falcon_get_lock() function, which is a rather crazy piece of code. This does not attempt to fix the driver's locking scheme in general, but at least prevents falcon_get_lock from going to sleep when no other thread holds the same lock or tries to get it, and we no longer schedule with irqs disabled. MSch: fixed completion conditions missed in Arnds' original RFC patch. Signed-off-by: Arnd Bergmann Acked-by: Michael Schmitz Cc: Geert Uytterhoeven Cc: James E.J. Bottomley Cc: linux-scsi@vger.kernel.org --- drivers/scsi/atari_scsi.c | 12 +++++++++--- 1 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/atari_scsi.c b/drivers/scsi/atari_scsi.c index a3e6c8a..296c936 100644 --- a/drivers/scsi/atari_scsi.c +++ b/drivers/scsi/atari_scsi.c @@ -90,6 +90,7 @@ #include #include #include +#include #include #include @@ -549,8 +550,10 @@ static void falcon_get_lock(void) local_irq_save(flags); - while (!in_irq() && falcon_got_lock && stdma_others_waiting()) - sleep_on(&falcon_fairness_wait); + wait_event_cmd(falcon_fairness_wait, + in_interrupt() || !falcon_got_lock || !stdma_others_waiting(), + local_irq_restore(flags), + local_irq_save(flags)); while (!falcon_got_lock) { if (in_irq()) @@ -562,7 +565,10 @@ static void falcon_get_lock(void) falcon_trying_lock = 0; wake_up(&falcon_try_wait); } else { - sleep_on(&falcon_try_wait); + wait_event_cmd(falcon_try_wait, + falcon_got_lock && !falcon_trying_lock, + local_irq_restore(flags), + local_irq_save(flags)); } } -- 1.7.0.4