Re: [V3 PATCH 4/4] scsi:stex.c Add S3/S4 support

From: Charles Chiou
Date: Sun Dec 14 2014 - 22:12:59 EST

On 12/10/2014 05:02 PM, Oliver Neukum wrote:
On Wed, 2014-12-10 at 09:38 +0800, Charles Chiou wrote:
From 91868d4afe10533b8a4496075109e411100217bb Mon Sep 17 00:00:00 2001
From: Charles Chiou <charles.chiou@xxxxxxxxxxxxxx>
Date: Fri, 7 Nov 2014 10:15:18 +0800
Subject: [PATCH 4/4] scsi:stex.c Add S3/S4 support

Add S3/S4 support, add .suspend and .resume function in pci_driver.

Pegasus need 30~40 seconds to boot up. We don't want to OS wait
in .resume function. Create a thread to handle device boot up.

+static int stex_resume(struct pci_dev *pdev)
+ struct st_hba *hba = pci_get_drvdata(pdev);
+ struct hba_handshake_workstruct *hswork;
+ int sts;
+ hba->mu_status = MU_STATE_STARTING;
+ hswork = kzalloc(sizeof(struct hba_handshake_workstruct), GFP_KERNEL);

The system is coming back from sleep. You cannot swap or page out
as disks may still be asleep. GFP_KERNEL is automatically changed
to GFP_NOIO. It would be nice to outright use GFP_NOIO.

+ INIT_WORK(&hswork->handshake_work, resume_handshake);

Memory allocations can fail.
I suggest you allocate the memory in suspend(). There you can just
return -ENOMEM in the error case.

Hi Oliver, sorry for the late reply.

Good point, could we move kzalloc function from suspend to probe and return -ENOMEM when allocation fail? We can avoid to allocate memory
again and again in suspend/resume cycles.

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