From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765438AbYHFIxQ (ORCPT ); Wed, 6 Aug 2008 04:53:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763553AbYHFIpT (ORCPT ); Wed, 6 Aug 2008 04:45:19 -0400 Received: from rv-out-0506.google.com ([209.85.198.238]:13145 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755024AbYHFIpN (ORCPT ); Wed, 6 Aug 2008 04:45:13 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=Q7y31Vhl+uJVhILCDXyCup5bMutoLCE+MFb22EVFteEMtK98RFm2OVNQZ83ZnbfCR7 5XM6fTpsxyJwn7KmE1mwlBScSm5PSWR4RiFUKOB1zaWL6TYMa8X1IcenJw3T7IftO2K7 Tw3ka4g8SOsBvii4qF3pbXXXzOKNgmhRzS2bM= From: Yinghai Lu To: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , "Eric W. Biederman" , Dhaval Giani , Mike Travis , Andrew Morton Cc: linux-kernel@vger.kernel.org, Yinghai Lu , Alan Cox Subject: [PATCH 21/33] serial: change remove NR_IRQS in 8250.c v2 Date: Wed, 6 Aug 2008 01:43:03 -0700 Message-Id: <1218012195-10429-22-git-send-email-yhlu.kernel@gmail.com> X-Mailer: git-send-email 1.5.4.5 In-Reply-To: <1218012195-10429-21-git-send-email-yhlu.kernel@gmail.com> References: <1218012195-10429-1-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-2-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-3-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-4-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-5-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-6-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-7-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-8-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-9-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-10-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-11-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-12-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-13-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-14-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-15-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-16-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-17-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-18-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-19-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-20-git-send-email-yhlu.kernel@gmail.com> <1218012195-10429-21-git-send-email-yhlu.kernel@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org use small array with index to handle irq locking for serial port hope 32 slot is enough v2: according to Eric, move irq_no into irq_info, and not clean irq_no Signed-off-by: Yinghai Lu Cc: Alan Cox --- drivers/serial/8250.c | 45 +++++++++++++++++++++++++++++++++++++++++---- 1 files changed, 41 insertions(+), 4 deletions(-) diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index 3920324..595b956 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -147,9 +147,39 @@ struct uart_8250_port { struct irq_info { spinlock_t lock; struct list_head *head; + int irq_no; }; -static struct irq_info irq_lists[NR_IRQS]; +#define NR_IRQ_INFO 32 + +static struct irq_info irq_lists[NR_IRQ_INFO] = { + [0 ... NR_IRQ_INFO-1] = { + .irq_no = -1, + } +}; + +static struct irq_info *get_irq_info(int irq, int with_free) +{ + int i, first_free = -1; + + for (i = 0; i < NR_IRQ_INFO; i++) { + if (irq_lists[i].irq_no == irq) + return &irq_lists[i]; + if (irq_lists[i].irq_no == -1 && first_free == -1) + first_free = i; + } + if (!with_free) + return NULL; + + if (first_free != -1) { + irq_lists[first_free].irq_no = irq; + return &irq_lists[first_free]; + } + + WARN_ON("NR_IRQ_INFO too small"); + + return NULL; +} /* * Here we define the default xmit fifo size used for each type of UART. @@ -1554,9 +1584,12 @@ static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up) static int serial_link_irq_chain(struct uart_8250_port *up) { - struct irq_info *i = irq_lists + up->port.irq; + struct irq_info *i = get_irq_info(up->port.irq, 1); int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0; + if (!i) + return -1; + spin_lock_irq(&i->lock); if (i->head) { @@ -1580,7 +1613,11 @@ static int serial_link_irq_chain(struct uart_8250_port *up) static void serial_unlink_irq_chain(struct uart_8250_port *up) { - struct irq_info *i = irq_lists + up->port.irq; + int irq_no = up->port.irq; + struct irq_info *i = get_irq_info(irq_no, 0); + + if (!i) + return; BUG_ON(i->head == NULL); @@ -2964,7 +3001,7 @@ static int __init serial8250_init(void) "%d ports, IRQ sharing %sabled\n", nr_uarts, share_irqs ? "en" : "dis"); - for (i = 0; i < nr_irqs; i++) + for (i = 0; i < NR_IRQ_INFO; i++) spin_lock_init(&irq_lists[i].lock); ret = uart_register_driver(&serial8250_reg); -- 1.5.4.5