RE: [PATCH V3 2/2] scsi: ufs: Set fDeviceInit flag to initiate device initialization

2013-07-11 Thread Dolev Raviv
On Tuesday, July 09, 2013, Sujit Reddy Thumma wrote: From: Dolev Raviv dra...@codeaurora.org Allow UFS device to complete its initialization and accept SCSI commands by setting fDeviceInit flag. The device may take time for this operation and hence the host should poll until fDeviceInit flag

Re: [PATCH V3 1/2] scsi: ufs: Add support for sending NOP OUT UPIU

2013-07-11 Thread Sujit Reddy Thumma
On 7/10/2013 6:58 PM, Seungwon Jeon wrote: On Tue, July 09, 2013, Sujit Reddy Thumma wrote: As part of device initialization sequence, sending NOP OUT UPIU and waiting for NOP IN UPIU response is mandatory. This confirms that the device UFS Transport (UTP) layer is functional and the host can

Re: [PATCH V3 1/2] scsi: ufs: Add support for host assisted background operations

2013-07-11 Thread Sujit Reddy Thumma
On 7/10/2013 7:01 PM, Seungwon Jeon wrote: I'm not sure that BKOPS with runtime-pm associates. Do you think it's helpful for power management? How about hibernation scheme for runtime-pm? I'm testing and I can introduce soon. Well, I am thinking on following approach when we introduce power

Re: [PATCH V3 2/2] scsi: ufs: Add runtime PM support for UFS host controller driver

2013-07-11 Thread Sujit Reddy Thumma
On 7/10/2013 7:01 PM, Seungwon Jeon wrote: On Tue, July 09, 2013, Sujit Reddy Thumma wrote: Add runtime PM helpers to suspend/resume UFS controller at runtime. Enable runtime PM by default for pci and platform drivers as the initialized hardware can suspend if it is not used after bootup.

[RFC/PATCH 0/4] block: Add support for urgent request handling in CFQ

2013-07-11 Thread Tanya Brokhman
In order to decrease the latency of a prioritized request (such as READ requests) the device driver might decide to stop the transmission of a current low priority request in order to handle the high priority one. The urgency of the request is decided by the block layer I/O scheduler. When the

[RFC/PATCH 2/4] block: Add support for reinsert a dispatched req

2013-07-11 Thread Tanya Brokhman
Add support for reinserting a dispatched request back to the scheduler's internal data structures. This capability is used by the device driver when it chooses to interrupt the current request transmission and execute another (more urgent) pending request. For example: interrupting long write in

[RFC/PATCH 1/4] block: make rq-cmd_flags be 64-bit

2013-07-11 Thread Tanya Brokhman
From: Jens Axboe ax...@kernel.dk We have officially run out of flags in a 32-bit space. Extend it to 64-bit even on 32-bit archs. Signed-off-by: Jens Axboe ax...@kernel.dk diff --git a/block/blk-core.c b/block/blk-core.c index 93a18d1..cfa4dd3 100644 --- a/block/blk-core.c +++

[RFC/PATCH 3/4] block: Add API for URGENT request handling

2013-07-11 Thread Tanya Brokhman
This patch add support in block elevator layers for handling urgent requests. The decision if a request is urgent or not is taken by the scheduler. Request is marked as urgent in cmd_flags (by the scheduler) with a new flag - REQ_URGENT. Urgent request notification is passed to the underlying

[RFC/PATCH 4/4] block: Add URGENT request notification support to CFQ scheduler

2013-07-11 Thread Tanya Brokhman
When the scheduler reports to the block layer that there is an urgent request pending, the device driver may decide to stop the transmission of the current request in order to handle the urgent one. This is done in order to reduce the latency of an urgent request. For example: long WRITE may be

Re: [RFC/PATCH 4/4] block: Add URGENT request notification support to CFQ scheduler

2013-07-11 Thread Santosh Y
On Thu, Jul 11, 2013 at 6:31 PM, Tanya Brokhman tlin...@codeaurora.org wrote: When the scheduler reports to the block layer that there is an urgent request pending, the device driver may decide to stop the transmission of the current request in order to handle the urgent one. This is done in

Re: [RFC/PATCH 4/4] block: Add URGENT request notification support to CFQ scheduler

2013-07-11 Thread Jeff Moyer
Tanya Brokhman tlin...@codeaurora.org writes: When the scheduler reports to the block layer that there is an urgent request pending, the device driver may decide to stop the transmission of the current request in order to handle the urgent one. This is done in order to reduce the latency of