From: Greg KH <greg@kroah.com>
To: Robert Love <rml@tech9.net>
Cc: Patrick Mochel <mochel@osdl.org>, Andrew Morton <akpm@digeo.com>,
sdake@mvista.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] udev enhancements to use kernel event queue
Date: Thu, 12 Jun 2003 16:25:23 -0700 [thread overview]
Message-ID: <20030612232523.GA1917@kroah.com> (raw)
In-Reply-To: <1055459762.662.336.camel@localhost>
On Thu, Jun 12, 2003 at 04:16:03PM -0700, Robert Love wrote:
> On Thu, 2003-06-12 at 16:09, Greg KH wrote:
>
> > +
> > + envp [i++] = scratch;
> > + scratch += sprintf(scratch, "SEQNUM=%ld", sequence_num) + 1;
> > + ++sequence_num;
>
> Since I do not see a lock in here, I think you need to use atomics?
>
> As is, you can also race and have the same sequence_num value written
> out twice.
Doh, I ate too much for lunch today and need to wake up...
Pat, here's an updated patch.
thanks,
greg k-h
diff -Nru a/lib/kobject.c b/lib/kobject.c
--- a/lib/kobject.c Thu Jun 12 16:21:21 2003
+++ b/lib/kobject.c Thu Jun 12 16:21:21 2003
@@ -100,6 +100,8 @@
#define BUFFER_SIZE 1024 /* should be enough memory for the env */
#define NUM_ENVP 32 /* number of env pointers */
+static unsigned long sequence_num;
+static spinlock_t sequence_lock = SPIN_LOCK_UNLOCKED;
static void kset_hotplug(const char *action, struct kset *kset,
struct kobject *kobj)
{
@@ -151,6 +153,12 @@
envp [i++] = scratch;
scratch += sprintf(scratch, "ACTION=%s", action) + 1;
+
+ spin_lock(&sequence_lock);
+ envp [i++] = scratch;
+ scratch += sprintf(scratch, "SEQNUM=%ld", sequence_num) + 1;
+ ++sequence_num;
+ spin_unlock(&sequence_lock);
kobj_path_length = get_kobj_path_length (kset, kobj);
kobj_path = kmalloc (kobj_path_length, GFP_KERNEL);
next prev parent reply other threads:[~2003-06-12 23:13 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-06-12 19:10 [PATCH] udev enhancements to use kernel event queue Steven Dake
2003-06-12 21:47 ` Patrick Mochel
2003-06-13 16:31 ` Steven Dake
2003-06-13 17:06 ` Patrick Mochel
2003-06-12 21:47 ` Greg KH
2003-06-12 22:03 ` Andrew Morton
2003-06-12 22:50 ` Greg KH
2003-06-12 22:51 ` Andrew Morton
2003-06-12 23:02 ` Greg KH
2003-06-12 23:09 ` Greg KH
2003-06-12 23:14 ` Patrick Mochel
2003-06-12 23:16 ` Robert Love
2003-06-12 23:25 ` Greg KH [this message]
2003-06-13 20:01 ` Oliver Neukum
2003-06-18 22:59 ` Greg KH
2003-06-19 0:12 ` Kevin P. Fleming
2003-06-19 0:20 ` Greg KH
2003-06-19 0:42 ` Kevin P. Fleming
2003-06-19 0:51 ` Greg KH
2003-06-19 0:25 ` Andrew Morton
2003-06-19 6:27 ` Oliver Neukum
2003-06-12 23:25 ` Patrick Mochel
2003-06-12 23:29 ` Robert Love
2003-06-12 23:32 ` Greg KH
2003-06-12 23:34 ` Patrick Mochel
2003-06-12 23:40 ` Paul Mackerras
2003-06-12 23:50 ` Robert Love
2003-06-13 12:44 ` Richard B. Johnson
2003-06-13 12:54 ` Olivier Galibert
2003-06-12 23:52 ` Patrick Mochel
2003-06-13 8:41 ` Alan Cox
2003-06-13 11:00 ` Paul Mackerras
2003-06-13 11:07 ` Herbert Xu
2003-06-13 13:31 ` Alan Cox
2003-06-13 19:57 ` Joe Korty
2003-06-13 21:10 ` Alan Cox
2003-06-13 11:17 ` David Schwartz
2003-06-13 15:44 ` Davide Libenzi
2003-06-12 23:42 ` Robert Love
2003-06-12 23:45 ` Davide Libenzi
2003-06-12 23:05 ` Robert Love
2003-06-19 19:51 ` Werner Almesberger
2003-06-26 12:17 ` Tommi Virtanen
2003-06-26 14:35 ` Werner Almesberger
2003-06-13 8:40 ` Alan Cox
2003-06-13 9:14 ` Olivier Galibert
2003-06-19 20:53 ` Werner Almesberger
2003-06-13 16:05 ` Steven Dake
2003-06-13 16:32 ` Greg KH
2003-06-13 15:51 ` Steven Dake
2003-06-13 16:41 ` Patrick Mochel
2003-06-13 16:42 ` Greg KH
2003-06-13 17:17 ` Chris Friesen
2003-06-12 22:27 ` Oliver Neukum
2003-06-13 16:03 ` Steven Dake
2003-06-13 16:50 ` Patrick Mochel
2003-06-13 17:10 ` Steven Dake
2003-06-13 18:26 ` Greg KH
2003-06-13 19:02 ` Patrick Mansfield
2003-06-13 17:32 ` Oliver Neukum
2003-06-13 18:23 ` Greg KH
2003-06-13 18:24 ` Greg KH
2003-06-13 7:17 ` Christoph Hellwig
2003-06-13 18:06 ` Linus Torvalds
2003-06-19 23:32 ` Werner Almesberger
2003-06-19 23:42 ` Steven Dake
2003-06-20 0:05 ` Linus Torvalds
2003-06-20 0:10 ` Steven Dake
2003-06-20 0:43 ` Linus Torvalds
2003-06-20 2:26 ` Werner Almesberger
2003-06-20 17:03 ` Steven Dake
2003-06-20 17:18 ` Patrick Mochel
2003-06-14 6:36 John Bradford
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