From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH 4/7 v2] RAS, debugfs: Add debugfs interface for RAS subsystem Date: Wed, 11 Jun 2014 21:01:13 +0200 Message-ID: <20140611190113.GD14923@pd.tnic> References: <1402475691-30045-1-git-send-email-gong.chen@linux.intel.com> <1402475691-30045-5-git-send-email-gong.chen@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Received: from mail.skyhub.de ([78.46.96.112]:37641 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752572AbaFKTBQ (ORCPT ); Wed, 11 Jun 2014 15:01:16 -0400 Content-Disposition: inline In-Reply-To: <1402475691-30045-5-git-send-email-gong.chen@linux.intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Chen, Gong" Cc: tony.luck@intel.com, m.chehab@samsung.com, rostedt@goodmis.org, linux-acpi@vger.kernel.org, lkml On Wed, Jun 11, 2014 at 04:34:48AM -0400, Chen, Gong wrote: > Implement a new debugfs interface for RAS susbsystem. > A file named daemon_active is added there accordingly. > This file is used to track if user space daemon enables > perf/trace interface or not. One can track which daemon > opens it via "lsof /path/to/debugfs/ras/daemon_active". > > v2 -> v1: Change file access mode from 0444 to 0400. > > Signed-off-by: Chen, Gong > --- > drivers/ras/Makefile | 2 +- > drivers/ras/debugfs.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++ > drivers/ras/ras.c | 14 +++++++++++++ > include/linux/ras.h | 15 ++++++++++++++ > 4 files changed, 87 insertions(+), 1 deletion(-) > create mode 100644 drivers/ras/debugfs.c > create mode 100644 include/linux/ras.h > > diff --git a/drivers/ras/Makefile b/drivers/ras/Makefile > index 223e806..d7f7334 100644 > --- a/drivers/ras/Makefile > +++ b/drivers/ras/Makefile > @@ -1 +1 @@ > -obj-$(CONFIG_RAS) += ras.o > +obj-$(CONFIG_RAS) += ras.o debugfs.o > diff --git a/drivers/ras/debugfs.c b/drivers/ras/debugfs.c > new file mode 100644 > index 0000000..d0bc389 > --- /dev/null > +++ b/drivers/ras/debugfs.c > @@ -0,0 +1,57 @@ > +#include > + > +struct dentry *ras_debugfs_dir; > +EXPORT_SYMBOL_GPL(ras_debugfs_dir); No need to export this. Revised version below: --- From: "Chen, Gong" Implement a new debugfs interface for RAS susbsystem. A file named daemon_active is added there accordingly. This file is used to track if user space daemon accesses perf/trace interface or not. One can track which daemon opens it via "lsof /path/to/debugfs/ras/daemon_active". Signed-off-by: Chen, Gong Link: http://lkml.kernel.org/r/1402475691-30045-5-git-send-email-gong.chen@linux.intel.com Signed-off-by: Borislav Petkov --- drivers/ras/Makefile | 2 +- drivers/ras/debugfs.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++ drivers/ras/ras.c | 14 +++++++++++++ include/linux/ras.h | 15 ++++++++++++++ 4 files changed, 87 insertions(+), 1 deletion(-) create mode 100644 drivers/ras/debugfs.c create mode 100644 include/linux/ras.h Index: linux/drivers/ras/Makefile =================================================================== --- linux.orig/drivers/ras/Makefile 2014-06-11 17:54:21.738397566 +0200 +++ linux/drivers/ras/Makefile 2014-06-11 17:54:21.726397566 +0200 @@ -1 +1 @@ -obj-$(CONFIG_RAS) += ras.o +obj-$(CONFIG_RAS) += ras.o debugfs.o Index: linux/drivers/ras/debugfs.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ linux/drivers/ras/debugfs.c 2014-06-11 17:58:47.214393178 +0200 @@ -0,0 +1,56 @@ +#include + +static struct dentry *ras_debugfs_dir; + +static atomic_t trace_count = ATOMIC_INIT(0); + +int ras_userspace_consumers(void) +{ + return atomic_read(&trace_count); +} +EXPORT_SYMBOL_GPL(ras_userspace_consumers); + +static int trace_show(struct seq_file *m, void *v) +{ + return atomic_read(&trace_count); +} + +static int trace_open(struct inode *inode, struct file *file) +{ + atomic_inc(&trace_count); + return single_open(file, trace_show, NULL); +} + +static int trace_release(struct inode *inode, struct file *file) +{ + atomic_dec(&trace_count); + return single_release(inode, file); +} + +static const struct file_operations trace_fops = { + .open = trace_open, + .read = seq_read, + .llseek = seq_lseek, + .release = trace_release, +}; + +int __init ras_add_daemon_trace(void) +{ + struct dentry *fentry; + + if (!ras_debugfs_dir) + return -ENOENT; + + fentry = debugfs_create_file("daemon_active", S_IRUSR, ras_debugfs_dir, + NULL, &trace_fops); + if (!fentry) + return -ENODEV; + + return 0; + +} + +void __init ras_debugfs_init(void) +{ + ras_debugfs_dir = debugfs_create_dir("ras", NULL); +} Index: linux/drivers/ras/ras.c =================================================================== --- linux.orig/drivers/ras/ras.c 2014-06-11 17:54:21.738397566 +0200 +++ linux/drivers/ras/ras.c 2014-06-11 17:54:21.730397566 +0200 @@ -5,8 +5,22 @@ * Chen, Gong */ +#include +#include + #define CREATE_TRACE_POINTS #define TRACE_INCLUDE_PATH ../../include/ras #include +static int __init ras_init(void) +{ + int rc = 0; + + ras_debugfs_init(); + rc = ras_add_daemon_trace(); + + return rc; +} +subsys_initcall(ras_init); + EXPORT_TRACEPOINT_SYMBOL_GPL(mc_event); Index: linux/include/linux/ras.h =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ linux/include/linux/ras.h 2014-06-11 17:58:43.350393242 +0200 @@ -0,0 +1,14 @@ +#ifndef __RAS_H__ +#define __RAS_H__ + +#ifdef CONFIG_DEBUG_FS +int ras_userspace_consumers(void); +void ras_debugfs_init(void); +int ras_add_daemon_trace(void); +#else +static inline int ras_userspace_consumers(void) { return 0; } +static inline void ras_debugfs_init(void) { return; } +static inline int ras_add_daemon_trace(void) { return 0; } +#endif + +#endif -- Regards/Gruss, Boris. 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