From patchwork Thu Oct 16 00:00:55 2008 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Kerr X-Patchwork-Id: 4649 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id E6349DDF26 for ; Thu, 16 Oct 2008 11:01:26 +1100 (EST) X-Original-To: cbe-oss-dev@ozlabs.org Delivered-To: cbe-oss-dev@ozlabs.org Received: by ozlabs.org (Postfix, from userid 1023) id 6F70BDDEE9; Thu, 16 Oct 2008 11:01:17 +1100 (EST) MIME-Version: 1.0 Message-Id: <1224115255.764374.459129262570.1.gpush@pingu> In-Reply-To: <1224115255.764116.272133018718.0.gpush@pingu> To: From: Jeremy Kerr Date: Thu, 16 Oct 2008 11:00:55 +1100 Subject: [Cbe-oss-dev] [PATCH 1/4] powerpc/spufs: sputrace: only enable logging on open(), prevent multiple openers X-BeenThere: cbe-oss-dev@ozlabs.org X-Mailman-Version: 2.1.11 Precedence: list List-Id: Discussion about Open Source Software for the Cell Broadband Engine List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cbe-oss-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.org Errors-To: cbe-oss-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.org Currently, sputrace will start logging to the event buffer before the log buffer has been open()ed. This results in a heap of "lost samples" warnings if the sputrace file hasn't yet been opened. Since the buffer is reset on open() anyway, there's no need to enable logging when no-one has opened the log. Because open clears the log, make it return EBUSY for mutliple open calls. Signed-off-by: Jeremy Kerr --- arch/powerpc/platforms/cell/spufs/sputrace.c | 32 ++++++++++++++++++++++++--- 1 file changed, 29 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/platforms/cell/spufs/sputrace.c b/arch/powerpc/platforms/cell/spufs/sputrace.c index 92d20e9..50cae0c 100644 --- a/arch/powerpc/platforms/cell/spufs/sputrace.c +++ b/arch/powerpc/platforms/cell/spufs/sputrace.c @@ -40,6 +40,7 @@ static DECLARE_WAIT_QUEUE_HEAD(sputrace_wait); static ktime_t sputrace_start; static unsigned long sputrace_head, sputrace_tail; static struct sputrace *sputrace_log; +static int sputrace_logging; static int sputrace_used(void) { @@ -109,24 +110,49 @@ static ssize_t sputrace_read(struct file *file, char __user *buf, static int sputrace_open(struct inode *inode, struct file *file) { + int rc; + spin_lock(&sputrace_lock); + if (sputrace_logging) { + rc = -EBUSY; + goto out; + } + + sputrace_logging = 1; sputrace_head = sputrace_tail = 0; sputrace_start = ktime_get(); + rc = 0; + +out: spin_unlock(&sputrace_lock); + return rc; +} +static int sputrace_release(struct inode *inode, struct file *file) +{ + spin_lock(&sputrace_lock); + sputrace_logging = 0; + spin_unlock(&sputrace_lock); return 0; } static const struct file_operations sputrace_fops = { - .owner = THIS_MODULE, - .open = sputrace_open, - .read = sputrace_read, + .owner = THIS_MODULE, + .open = sputrace_open, + .read = sputrace_read, + .release = sputrace_release, }; static void sputrace_log_item(const char *name, struct spu_context *ctx, struct spu *spu) { spin_lock(&sputrace_lock); + + if (!sputrace_logging) { + spin_unlock(&sputrace_lock); + return; + } + if (sputrace_avail() > 1) { struct sputrace *t = sputrace_log + sputrace_head;