[lkml]   [2005]   [Mar]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH rc1-mm3] timers: simplify locking
Andrew Morton wrote:
> Oleg Nesterov <> wrote:
> >
> > This is the last one, I promise.
> > On top of "[PATCH rc1-mm3] timers: kill timer_list->lock", see
> >
> I thought that earlier patch was a bit weird

A bit weird, or too weird to be acceptable?

I am very much interested in your and others opinion. You do not like
this fake_timer_base or you don't like the idea that the timer is always
locked through timer_base() ?

These 2 patches should be cleanuped of course.

struct XXX {
spinlock_t lock;
timer_list *running_timer;

struct XXX fake_timer_base;

struct tvec_t_base_s {
struct XXX xxx;

long timer_jiffies;
tvec_t tv1;

struct timer_list {
struct XXX *_base;

So tvec_t_base_s is used only in __mod_timer() for new_base. This cleanup
would be trivial and without changes in timer.o.

However this global fake_timer_base is really neccessary for this patch and
it is really wierd.

But I like the fact that __mod_timer() takes 2 locks sequentially instead
of 3 at once.

> and I think it would be better
> to get to the bottom of these problems which people have been reporting in
> the 2.6.12-rc1-mm3 timer code before adding more things, don't you?

I just can't imagine how this "del_timer_sync instead of del_singleshot_timer
in schedule_timeout" can reveal any bug in these patches. del_singleshot_timer
calls del_timer_sync anyway when the timer is inactive. The only difference
is that now schedule_timeout()->del_timer_sync() actually deletes this timer
when the caller was waken by a signal/event. And that deletion is very simple,
it just "can't be wrong", and it adds LIST_POISON to timer->entry.

But you are right of course. It is better to forget about these new patches
for a while.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-04-06 13:31    [W:0.087 / U:7.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site