Re: [PATCH RESEND 2/5] kexec: Export kexec_in_progress

[Brian King <brking@linux.vnet.ibm.com>]

On 12/02/2014 12:49 PM, Brian King wrote:
> On 12/02/2014 12:47 PM, Brian King wrote:
>> A kexec boot for some ipr SAS adapters was seen to take ~20 seconds
>> just doing ipr adapter initialization. This is due to the fact that
>> a kexec invokes the driver's shutdown handler which places the adapter
>> into a state that requires a hard reset and resulting firmware initialization
>> to be usable again, which takes significant time. By exporting kexec_in_progress,
>> this process can be optimized significantly in the driver by essentially
>> placing the adapter into a state where this hardware reset and re-initialization
>> can be bypassed, eliminating this delay in kexec boot.
>>
>> Cc: Eric Biederman <ebiederm@xmission.com>
>> Cc: kexec <kexec@lists.infradead.org>
>> Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
>> ---
>>
>>  kernel/kexec.c |    2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff -puN kernel/kexec.c~kexec_export_in_prog kernel/kexec.c
>> --- scsi-queue/kernel/kexec.c~kexec_export_in_prog	2014-12-02 12:13:22.820325731 -0600
>> +++ scsi-queue-bjking1/kernel/kexec.c	2014-12-02 12:13:22.825325687 -0600
>> @@ -2768,3 +2768,5 @@ int kernel_kexec(void)
>>  	mutex_unlock(&kexec_mutex);
>>  	return error;
>>  }
>> +
>> +EXPORT_SYMBOL_GPL(kexec_in_progress);
>> _
>>
> 
> Eric,
> 
> Can I get your ack on this so this can go through the scsi tree? The last time I sent this
> out you had some issues with the patch description.

Eric - can I get your ack here?

Thanks,

Brian


-- 
Brian King
Power Linux I/O
IBM Linux Technology Center