Re: [Patch 3/9] Block I/O accounting initialization

>  
> +static inline void delayacct_blkio_start(void)
> +{
> +	if (unlikely(delayacct_on))
> +		__delayacct_blkio_start();
> +}


I still think the unlikely() makes no sense here; at runtime it's either
going to be always on or off (in the sense that switching it will be
RARE). The cpus branch predictor will get that right; while if you force
it unlikely you can even run the risk of getting a 100% miss on some
architectures (not x86/x86-64) when you enable the accounting


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

---

• Follow-Ups:
  • Re: [Patch 3/9] Block I/O accounting initialization
    • From: Shailabh Nagar <[email protected]>

• References:
  • [Patch 0/9] Per-task delay accounting
    • From: Shailabh Nagar <[email protected]>
  • [Patch 3/9] Block I/O accounting initialization
    • From: Shailabh Nagar <[email protected]>

• Prev by Date: Re: [RFC, PATCH 0/24] VMI i386 Linux virtualization interface proposal
• Next by Date: Re: [Patch 1/9] timestamp diff
• Previous by thread: [Patch 3/9] Block I/O accounting initialization
• Next by thread: Re: [Patch 3/9] Block I/O accounting initialization
• Index(es):
  • Date
  • Thread

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]