Commit graph

17 commits

Author SHA1 Message Date
Daniel Walker
0719e3702e whitespace fixes: interval timers
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:26 -07:00
Adrian Bunk
35bab756b4 The scheduled -EINVAL for invalid timevals in setitimer
As scheduled, do_setitimer() now returns -EINVAL for invalid timeval.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:13 -07:00
Randy Dunlap
e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Thomas Gleixner
8bfd9a7a22 [PATCH] hrtimers: prevent possible itimer DoS
Fix potential setitimer DoS with high-res timers by pushing itimer rearm
processing to process context.

[Fixes from: Ingo Molnar <mingo@elte.hu>]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 08:13:59 -08:00
Thomas Gleixner
54cdfdb47f [PATCH] hrtimers: add high resolution timer support
Implement high resolution timers on top of the hrtimers infrastructure and the
clockevents / tick-management framework.  This provides accurate timers for
all hrtimer subsystem users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 08:13:59 -08:00
Thomas Gleixner
c9cb2e3d7c [PATCH] hrtimers: namespace and enum cleanup
- hrtimers did not use the hrtimer_restart enum and relied on the implict
  int representation. Fix the prototypes and the functions using the enums.
- Use seperate name spaces for the enumerations
- Convert hrtimer_restart macro to inline function
- Add comments

No functional changes.

[akpm@osdl.org: fix input driver]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 08:13:58 -08:00
Roman Zippel
05cfb614dd [PATCH] hrtimers: remove data field
The nanosleep cleanup allows to remove the data field of hrtimer.  The
callback function can use container_of() to get it's own data.  Since the
hrtimer structure is anyway embedded in other structures, this adds no
overhead.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:03 -08:00
Roman Zippel
44f2147551 [PATCH] hrtimers: pass current time to hrtimer_forward()
Pass current time to hrtimer_forward().  This allows to use the softirq time
in the timer base when the forward function is called from the timer callback.
 Other places pass current time with a call to timer->base->get_time().

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:02 -08:00
Thomas Gleixner
7d99b7d634 [PATCH] Validate and sanitze itimer timeval from userspace
According to the specification the timevals must be validated and an
errorcode -EINVAL returned in case the timevals are not in canonical form.
This check was never done in Linux.

The pre 2.6.16 code converted invalid timevals silently.  Negative timeouts
were converted by the timeval_to_jiffies conversion to the maximum timeout.

hrtimers and the ktime_t operations expect timevals in canonical form.
Otherwise random results might happen on 32 bits machines due to the
optimized ktime_add/sub operations.  Negative timeouts are treated as
already expired.  This might break applications which work on pre 2.6.16.

To prevent random behaviour and API breakage the timevals are checked and
invalid timevals sanitized in a simliar way as the pre 2.6.16 code did.

Invalid timevals are reported with a per boot limited number of kernel
messages so applications which use this misfeature can be corrected.

After a grace period of one year the sanitizing should be replaced by a
correct validation check.  This is also documented in
Documentation/feature-removal-schedule.txt

The validation and sanitizing is done inside do_setitimer so all callers
(sys_setitimer, compat_sys_setitimer, osf_setitimer) are catched.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:49 -08:00
Thomas Gleixner
c08b8a4910 [PATCH] sys_alarm() unsigned signed conversion fixup
alarm() calls the kernel with an unsigend int timeout in seconds.  The
value is stored in the tv_sec field of a struct timeval to setup the
itimer.  The tv_sec field of struct timeval is of type long, which causes
the tv_sec value to be negative on 32 bit machines if seconds > INT_MAX.

Before the hrtimer merge (pre 2.6.16) such a negative value was converted
to the maximum jiffies timeout by the timeval_to_jiffies conversion.  It's
not clear whether this was intended or just happened to be done by the
timeval_to_jiffies code.

hrtimers expect a timeval in canonical form and treat a negative timeout as
already expired.  This breaks the legitimate usage of alarm() with a
timeout value > INT_MAX seconds.

For 32 bit machines it is therefor necessary to limit the internal seconds
value to avoid API breakage.  Instead of doing this in all implementations
of sys_alarm the duplicated sys_alarm code is moved into a common function
in itimer.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:48 -08:00
Thomas Gleixner
a16a1c095a [PATCH] hrtimers: fix oldvalue return in setitimer
This resolves bugzilla bug#5617.  The oldvalue of the timer was read after the
timer was cancelled, so the remaining time was always zero.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:12 -08:00
Thomas Gleixner
bc1978d404 [PATCH] hrtimers: fixup itimer conversion
The itimer conversion removed the locking which protects the timer and
variables in the shared signal structure.  Steven Rostedt found the problem in
the latest -rt patches.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:12 -08:00
Thomas Gleixner
2ff678b8da [PATCH] hrtimer: switch itimers to hrtimer
switch itimers to a hrtimers-based implementation

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:38 -08:00
George Anzinger
d912d1ff21 [PATCH] itimer fixes
Fix the recent off-by-one fix in the itimer code:

1. The repeating timer is figured using the requested time
	(not +1 as we know where we are in the jiffie).

2. The tests for interval too large are left to the time_val to jiffie code.

Signed-off-by: George Anzinger <george@mvista.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:25:51 -07:00
Oleg Nesterov
f01b1b0baa [PATCH] ITIMER_REAL: fix possible deadlock and race
As Steven Rostedt pointed out, there are 2 problems with ITIMER_REAL
timers.

1. do_setitimer() does not call del_timer_sync() in case
   when the timer is not pending (it_real_value() returns 0).
   This is wrong, the timer may still be running, and it can
   rearm itself.

2. It calls del_timer_sync() with tsk->sighand->siglock held.
   This is deadlockable, because timer's handler needs this
   lock too.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 21:20:30 -07:00
Paulo Marques
b7e4e85337 [PATCH] setitimer timer expires too early
It seems that the code responsible for this is in kernel/itimer.c:126:

	p->signal->real_timer.expires = jiffies + interval;
	add_timer(&p->signal->real_timer);

If you request an interval of, lets say 900 usecs, the interval given by
timeval_to_jiffies will be 1.

If you request this when we are half-way between two timer ticks, the
interval will only give 400 usecs.

If we want to guarantee that we never ever give intervals less than
requested, the simple solution would be to change that to:

	p->signal->real_timer.expires = jiffies + interval + 1;

This however will produce pathological cases, like having a idle system
being requested 1 ms timeouts will give systematically 2 ms timeouts,
whereas currently it simply gives a few usecs less than 1 ms.

The complex (and more computationally expensive) solution would be to
check the gettimeofday time, and compute the correct number of jiffies.
This way, if we request a 300 usecs timer 200 usecs inside the timer
tick, we can wait just one tick, but not if we are 800 usecs inside the
tick. This would also mean that we would have to lock preemption during
these computations to avoid races, etc.

I've searched the archives but couldn't find this particular issue being
discussed before.

Attached is a patch to do the simple solution, in case anybody thinks
that it should be used.

Signed-Off-By: Paulo Marques <pmarques@grupopie.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:41 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00