percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
On Tue, Feb 02, 2010 at 02:57:14PM -0800, Greg KH (gregkh@suse.de) wrote:
> > There are at least two ways to fix it: using a big cannon and a small
> > one. The former way is to disable notification registration, since it is
> > not used by anyone at all. Second way is to check whether calling
> > process is root and its destination group is -1 (kind of priveledged
> > one) before command is dispatched to workqueue.
>
> Well if no one is using it, removing it makes the most sense, right?
>
> No objection from me, care to make up a patch either way for this?
Getting it is not used, let's drop support for notifications about
(un)registered events from connector.
Another option was to check credentials on receiving, but we can always
restore it without bugs if needed, but genetlink has a wider code base
and none complained, that userspace can not get notification when some
other clients were (un)registered.
Kudos for Sebastian Krahmer <krahmer@suse.de>, who found a bug in the
code.
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 7069331 (connector: Provide the sender's credentials to the
callback, 2009-10-02) changed callbacks to take two arguments but missed
this one.
drivers/connector/cn_proc.c: In function ‘cn_proc_init’:
drivers/connector/cn_proc.c:263: warning: passing argument 3 of
‘cn_add_callback’ from incompatible pointer type
Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The act of a process becoming a session leader is a useful signal to a
supervising init daemon such as Upstart.
While a daemon will normally do this as part of the process of becoming a
daemon, it is rare for its children to do so. When the children do, it is
nearly always a sign that the child should be considered detached from the
parent and not supervised along with it.
The poster-child example is OpenSSH; the per-login children call setsid()
so that they may control the pty connected to them. If the primary daemon
dies or is restarted, we do not want to consider the per-login children
and want to respawn the primary daemon without killing the children.
This patch adds a new PROC_SID_EVENT and associated structure to the
proc_event event_data union, it arranges for this to be emitted when the
special PIDTYPE_SID pid is set.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Scott James Remnant <scott@ubuntu.com>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The connector documentation states that the argument to the callback
function is always a pointer to a struct cn_msg, but rather than encode it
in the API itself, it uses a void pointer everywhere. This doesn't make
much sense to encode the pointer in documentation as it prevents proper C
type checking from occurring and can easily allow people to use the wrong
pointer type. So convert the argument type to an explicit struct cn_msg
pointer.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
.ko is normally not included in Kconfig help, make it consistent.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The netlink connector uses its own workqueue to relay the datas sent
from userspace to the appropriate callback. If you launch the test
from Documentation/connector and change it a bit to send a high flow
of data, you will see thousands of events coming to the "cqueue"
workqueue by looking at the workqueue tracer.
This flow of events can be sent very quickly. So, to not encumber the
kevent workqueue and delay other jobs, the "cqueue" workqueue should
remain.
But this workqueue is pointless most of the time, it will always be
created (assuming you have built it of course) although only
developpers with specific needs will use it.
So avoid this "most of the time useless task", this patch proposes to
create this workqueue only when needed once. The first jobs to be
sent to connector callbacks will be sent to kevent while the "cqueue"
thread creation will be scheduled to kevent too.
The following jobs will continue to be scheduled to keventd until the
cqueue workqueue is created, and then the rest of the jobs will
continue to perform as usual, through this dedicated workqueue.
Each time I tested this patch, only the first event was sent to
keventd, the rest has been sent to cqueue which have been created
quickly.
Also, this patch fixes some trailing whitespaces on the connector files.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use RCU to access another task's creds and to release a task's own creds.
This means that it will be possible for the credentials of a task to be
replaced without another task (a) requiring a full lock to read them, and (b)
seeing deallocated memory.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Separate the task security context from task_struct. At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.
Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.
With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
I got a problem when I wanted to check if the kernel supports process
event connector, and It seems there's no way to do this check.
At best I can check if the kernel supports connector or not, by looking
into /proc/net/netlink, or maybe checking the return value of bind() to
see if it's ENOENT.
So it would be useful to add /proc/net/connector to list all supported
connectors:
# cat /proc/net/connector
Name ID
connector 4294967295:4294967295
cn_proc 1:1
w1 3:1
Changelog:
- fix memory leak: s/seq_release/single_release
- use spin_lock_bh instead of spin_lock_irqsave
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
We don't need one cqueue thread for each CPU. cqueue is used for
receiving userspace datagrams, which are very rare and thus will
happily live with a single queue.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Create a specific helper for netlink kernel socket disposal. This just
let the code look better and provides a ground for proper disposal
inside a namespace.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Tested-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
- 'cb' is a fake struct member. In a previous patch struct cn_callback
was renamed to cn_callback_id, so 'cb' should have been deleted at that
time.
- 'nls' isn't used and is redundant, we can retrieve this data through
cn_callback_entry.pdev->nls.
- 'seq' and 'group' should be u32, as they are declared to be u32 in
other places.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Struct member netlink_groups is never used, and I don't see how it can
be useful.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- __cn_rx_skb() does nothing but calls cn_call_callback(), it doesn't
check skb and msg sizes as the comment suggests, but cn_rx_skb() checks
those sizes.
- In cn_rx_skb() Local variable 'len' is not used. 'len' is probably
intended to be passed to skb_pull(), but here skb_pull() is not needed,
instead skb_free() is called.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Each entry in the list has a unique id, so just break out of the
loop if the matched id is found.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
cn_queue_free_callback() will touch 'dev'(i.e. cbq->pdev), so it
should be called before atomic_dec(&dev->refcnt).
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Error code should be set to EINVAL instead of ENODEV if !queue_work().
There's another call of queue_work() which may set err to EINVAL.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove a spurious call to kfree_skb() in the connector rx_skb handler.
This fixes a regression introduced by the '[NET]: make netlink user ->
kernel interface synchronious' patch (cd40b7d398)
Signed-off-by: Michal Januszewski <spock@gentoo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
