On 9/15/06, Tejun Heo <htejun@xxxxxxxxx> wrote:
On Fri, Sep 15, 2006 at 09:12:33AM -0600, Fajun Chen wrote:
> Hi,
>
> I'm trying to speed up the SATA hotplug sequence so I can measure the
> disk spinup time more accurately. I noticed two delays which may be
> unnecessary in SATA hotplug:
> 1. About 4-5 seconds delay during power cycle (power down then power
> up) as shown below (detail log at the end):
> [65642.680000] ata_eh_prep_resume: ENTER
> [65642.680000] ata_eh_prep_resume: EXIT
> [65642.680000] __ata_port_freeze: ata2 port frozen
> [65646.970000] ata2: soft resetting port
> [65646.970000] sil24_softreset: ENTER
> Question: where is the delay introduced and can we eliminate this delay?
It's probably waiting for ATA_BUSY to clear in prereset.
> 2. Soft reset fails sometimes then followed by a successful hard reset.
> Question: may I do hard reset to start with and where is the best
> place to change this? I know sata spec recommend attempting less
> intrusive recovery procedure first, but I need to eliminate as much
> unnecessary delay as possible.
ATA_FLAG_HRST_TO_RESUME. You probably also want to tweak
ATA_SPINUP_WAIT.
Tejun, I use SATA Sil24. Where should ATA_FLAG_HRST_TO_RESUME be
flagged? I made one attempt by making the following change in
libata.h and it seems not working sometimes (see log at the end)? I'm
a little puzzled by different flags such as ap->flags, ehc->flags...
Is there any document about new eh?
static inline void __ata_ehi_hotplugged(struct ata_eh_info *ehi)
{
if (ehi->flags & ATA_EHI_HOTPLUGGED)
return;
ehi->flags |= ATA_EHI_HOTPLUGGED | ATA_EHI_RESUME_LINK;
ehi->hotplug_timestamp = jiffies;
ehi->action |= ATA_EH_HARDRESET; // My Change for Hard Reset
ehi->probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
}
...
[ 5985.450000] ata1: EH pending after completion, repeating EH (cnt=4)
[ 5985.450000] ata_eh_autopsy: ENTER
[ 5985.450000] ata_eh_autopsy: EXIT
[ 5985.450000] ata1: exception Emask 0x10 SAct 0x0 SErr 0x0 action 0x1
[ 5985.450000] ata1: (irq_stat 0x00b40090, PHY RDY changed)
[ 5985.450000] ata_eh_recover: ENTER
[ 5985.450000] ata_eh_prep_resume: ENTER
[ 5985.450000] ata_eh_prep_resume: EXIT
[ 5985.450000] __ata_port_freeze: ata1 port frozen
[ 5985.450000] ata_wait_spinup: ENTER
[ 5985.450000] sata_phy_debounce: ENTER
[ 5985.970000] sata_phy_debounce: EXIT
[ 5988.990000] ata_wait_spinup: EXIT
[ 5988.990000] sata_phy_resume: ENTER
[ 5989.200000] sata_phy_debounce: ENTER
[ 5989.720000] sata_phy_debounce: EXIT
[ 5989.720000] sata_phy_resume: EXIT
[ 5989.720000] ata1: soft resetting port
[ 5989.720000] sil24_softreset: ENTER
[ 5989.830000] ata_dev_classify: found ATA device by sig
[ 5989.830000] sil24_softreset: EXIT, class=1
[ 5989.830000] ata_std_postreset: ENTER
[ 5989.830000] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
...
-
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
