Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756698AbZCWNMw (ORCPT ); Mon, 23 Mar 2009 09:12:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756409AbZCWNMG (ORCPT ); Mon, 23 Mar 2009 09:12:06 -0400 Received: from fg-out-1718.google.com ([72.14.220.152]:46849 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756384AbZCWNMB (ORCPT ); Mon, 23 Mar 2009 09:12:01 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; b=wCkQp7vC9Q/AK1H+FHrQOYbB2SDaXypFVETKw3KyKLbEDZzz26B3aMEUtx5KIZh2hB PXJFIgm8wTSsrdDCogVhObAOCY+IQ2WvXvCSn/WVS6raLvNYUMNd2rUc7u30+1zWOPMG ahpAdDFOtpUvHrK0yzbwwFLLGTf74VY6EsToI= From: Eduard - Gabriel Munteanu To: mingo@elte.hu Cc: rostedt@goodmis.org, compudj@krystal.dyndns.org, fweisbec@gmail.com, penberg@cs.helsinki.fi, paulmck@linux.vnet.ibm.com, Eduard - Gabriel Munteanu , linux-kernel@vger.kernel.org Subject: [PATCH 2/7] tracing: provide trace_seq_reserve() Date: Mon, 23 Mar 2009 15:12:22 +0200 Message-Id: <6698c7b983cc20ec84becc757362f48a8948762d.1237813499.git.eduard.munteanu@linux360.ro> X-Mailer: git-send-email 1.6.0.6 In-Reply-To: <75eba730cfee8e771090b60c4b252bd8d3ffcb18.1237813499.git.eduard.munteanu@linux360.ro> References: <75eba730cfee8e771090b60c4b252bd8d3ffcb18.1237813499.git.eduard.munteanu@linux360.ro> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1948 Lines: 54 trace_seq_reserve() allows a caller to reserve space in a trace_seq and write directly into it. This makes it easier to export binary data to userspace via the tracing interface, by simply filling in a struct. Signed-off-by: Eduard - Gabriel Munteanu --- kernel/trace/trace_output.c | 13 +++++++++++++ kernel/trace/trace_output.h | 1 + 2 files changed, 14 insertions(+), 0 deletions(-) diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 9fc8150..bdcc3fe 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -116,6 +116,19 @@ int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len) return trace_seq_putmem(s, hex, j); } +void *trace_seq_reserve(struct trace_seq *s, size_t len) +{ + void *ret; + + if (len > ((PAGE_SIZE - 1) - s->len)) + return NULL; + + ret = s->buffer + s->len; + s->len += len; + + return ret; +} + int trace_seq_path(struct trace_seq *s, struct path *path) { unsigned char *p; diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h index 551a25a..cbc0ec8 100644 --- a/kernel/trace/trace_output.h +++ b/kernel/trace/trace_output.h @@ -27,6 +27,7 @@ int trace_seq_puts(struct trace_seq *s, const char *str); int trace_seq_putc(struct trace_seq *s, unsigned char c); int trace_seq_putmem(struct trace_seq *s, void *mem, size_t len); int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len); +void *trace_seq_reserve(struct trace_seq *s, size_t len); int trace_seq_path(struct trace_seq *s, struct path *path); int seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s, unsigned long sym_flags); -- 1.6.0.6 -- 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/