Re: [PATCHv2 2/8] fs/timerfd.c: make use of wait_event_interruptible_locked_irq()

From: Michal Nazarewicz
Date: Sun Apr 11 2010 - 15:16:48 EST


> On Fri, 9 Apr 2010, Michal Nazarewicz wrote:
>> diff --git a/fs/timerfd.c b/fs/timerfd.c
>> index 1bfc95a..4d2c371 100644
>> --- a/fs/timerfd.c
>> +++ b/fs/timerfd.c
>> @@ -109,31 +109,13 @@ static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count,
>> struct timerfd_ctx *ctx = file->private_data;
>> ssize_t res;
>> u64 ticks = 0;
>> - DECLARE_WAITQUEUE(wait, current);
>>
>> if (count < sizeof(ticks))
>> return -EINVAL;
>> spin_lock_irq(&ctx->wqh.lock);
>> res = -EAGAIN;
>> - if (!ctx->ticks && !(file->f_flags & O_NONBLOCK)) {
>> - __add_wait_queue(&ctx->wqh, &wait);
>> - for (res = 0;;) {
>> - set_current_state(TASK_INTERRUPTIBLE);
>> - if (ctx->ticks) {
>> - res = 0;
>> - break;
>> - }
>> - if (signal_pending(current)) {
>> - res = -ERESTARTSYS;
>> - break;
>> - }
>> - spin_unlock_irq(&ctx->wqh.lock);
>> - schedule();
>> - spin_lock_irq(&ctx->wqh.lock);
>> - }
>> - __remove_wait_queue(&ctx->wqh, &wait);
>> - __set_current_state(TASK_RUNNING);
>> - }
>> + if (!(file->f_flags & O_NONBLOCK))
>> + wait_event_interruptible_locked_irq(ctx->wqh, ctx->ticks);

Thomas Gleixner <tglx@xxxxxxxxxxxxx> writes:
> With this change we return -EAGAIN instead of -ERESTARTSYS when the
> wait got interrupted by a signal. That means instead of restarting the
> syscall we return -EAGAIN to user space.

Stupid mistake, the following should fix it:

+ res = wait_event_interruptible_locked_irq(ctx->wqh, ctx->ticks);

Sorry about that.

I'll resubmit an updated patchset by the end of the week.

--
Best regards, _ _
.o. | Liege of Serenly Enlightened Majesty of o' \,=./ `o
..o | Computer Science, Michal "mina86" Nazarewicz (o o)
ooo +--<mina86-tlen.pl>--<jid:mina86-jabber.org>--ooO--(_)--Ooo--
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