Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755382Ab2KMROb (ORCPT ); Tue, 13 Nov 2012 12:14:31 -0500 Received: from mail-lb0-f174.google.com ([209.85.217.174]:49028 "EHLO mail-lb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754907Ab2KMRO1 (ORCPT ); Tue, 13 Nov 2012 12:14:27 -0500 Date: Tue, 13 Nov 2012 21:14:22 +0400 From: Cyrill Gorcunov To: Oleg Nesterov , Pavel Emelyanov Cc: Al Viro , Alexey Dobriyan , James Bottomley , "Aneesh Kumar K.V" , Matthew Helsley , "J. Bruce Fields" , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: + fs-epoll-add-procfs-fdinfo-helper.patch added to -mm tree Message-ID: <20121113171422.GM7808@moon> References: <20121113145050.GA13691@redhat.com> <20121113155313.GU6511@moon> <20121113162056.GK7808@moon> <20121113164951.GA18665@redhat.com> <20121113170159.GW6511@moon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121113170159.GW6511@moon> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3347 Lines: 101 On Tue, Nov 13, 2012 at 09:01:59PM +0400, Cyrill Gorcunov wrote: > > As from c/r patch I think we can read it lockless (since we do stop > tasks anyway before doing checkpoint). So I would prefer to provide > it without locks at all. Something like this. (Also I wonder where the documentation about fdinfo should go?) --- From: Cyrill Gorcunov Subject: fdinfo: Show sigmask for signalfd fd v3 The sigmask is read in lockless manner for a sake of code simplicity, thus if precise data needed here the tasks which refer to the signalfd should be stopped before read. Signed-off-by: Cyrill Gorcunov CC: Pavel Emelyanov CC: Al Viro CC: Alexey Dobriyan CC: Andrew Morton CC: James Bottomley CC: "Aneesh Kumar K.V" CC: Alexey Dobriyan CC: Matthew Helsley CC: "J. Bruce Fields" CC: "Aneesh Kumar K.V" --- fs/proc/array.c | 2 +- fs/signalfd.c | 18 ++++++++++++++++++ include/linux/proc_fs.h | 3 +++ 3 files changed, 22 insertions(+), 1 deletion(-) Index: linux-2.6.git/fs/proc/array.c =================================================================== --- linux-2.6.git.orig/fs/proc/array.c +++ linux-2.6.git/fs/proc/array.c @@ -220,7 +220,7 @@ static inline void task_state(struct seq seq_putc(m, '\n'); } -static void render_sigset_t(struct seq_file *m, const char *header, +void render_sigset_t(struct seq_file *m, const char *header, sigset_t *set) { int i; Index: linux-2.6.git/fs/signalfd.c =================================================================== --- linux-2.6.git.orig/fs/signalfd.c +++ linux-2.6.git/fs/signalfd.c @@ -29,6 +29,7 @@ #include #include #include +#include void signalfd_cleanup(struct sighand_struct *sighand) { @@ -227,7 +228,24 @@ static ssize_t signalfd_read(struct file return total ? total: ret; } +#ifdef CONFIG_PROC_FS +static int signalfd_show_fdinfo(struct seq_file *m, struct file *f) +{ + struct signalfd_ctx *ctx = f->private_data; + sigset_t sigmask; + + sigmask = ctx->sigmask; + signotset(&sigmask); + render_sigset_t(m, "sigmask:\t", &sigmask); + + return 0; +} +#endif + static const struct file_operations signalfd_fops = { +#ifdef CONFIG_PROC_FS + .show_fdinfo = signalfd_show_fdinfo, +#endif .release = signalfd_release, .poll = signalfd_poll, .read = signalfd_read, Index: linux-2.6.git/include/linux/proc_fs.h =================================================================== --- linux-2.6.git.orig/include/linux/proc_fs.h +++ linux-2.6.git/include/linux/proc_fs.h @@ -290,4 +290,7 @@ static inline struct net *PDE_NET(struct return pde->parent->data; } +#include + +void render_sigset_t(struct seq_file *m, const char *header, sigset_t *set); #endif /* _LINUX_PROC_FS_H */ -- 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/