kernel.git/drivers/s390/cio/css.c, branch linux-4.20.y

s390/css: reduce stsch calls

2018-07-17T05:27:55Z

Both css_evaluate_new_subchannel and cio_validate_subchannel used stsch and css_sch_is_valid to check for a valid device. Reduce stsch calls during subchannel evaluation by re-using schib data. Also the type/devno valid information is only checked once. Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky

s390/css: validate subchannel prior to allocation

2018-07-17T05:27:54Z

In css_alloc_subchannel we allocate the subchannel and do a validation of the subchannel (to decide if we should look for devices via this subchannel). On a typical LPAR we find lots of subchannels to be invalid (because there is no device attached or the device is blacklisted) leading to lots of useless kmalloc and kfree calls. This patch changes the order to only allocate the subchannels that have been found valid. Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky

s390/css: start the subchannel evaluation earlier

2018-07-17T05:27:53Z

The css bus code uses 2 initcalls: channel_subsystem_init to initialize internal data and channel_subsystem_init_sync to start scanning for devices and wait for it to finish. The start scanning for devices part is moved to the first initcall such that more work happens in parallel. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390/cio: ensure that a chpid is registered only once

2018-07-17T05:27:51Z

Improve locking in chp_new to make sure that we don't register the same chpid twice. Chpid registration was synchronized via the machine check handler thread but we also have codepaths to look for new chpids triggered independent of that thread (during IPL or resume from hibernate). Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky

treewide: Use DEVICE_ATTR_RO

2018-01-09T15:34:34Z

Convert DEVICE_ATTR uses to DEVICE_ATTR_RO where possible. Done with perl script: $ git grep -w --name-only DEVICE_ATTR | \ xargs perl -i -e 'local $/; while (<>) { s/\bDEVICE_ATTR\s*$\s*(\w+)\s*,\s*\(?(?:\s*S_IRUGO\s*|\s*0444\s*)$?\s*,\s*\1_show\s*,\s*NULL\s*\)/DEVICE_ATTR_RO(\1)/g; print;}' Signed-off-by: Joe Perches Acked-by: Rafael J. Wysocki Acked-by: Robert Jarzmik Acked-by: Sagi Grimberg Acked-by: Zhang Rui Acked-by: Harald Freudenberger Acked-by: Jani Nikula Acked-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

s390: drivers: Remove redundant license text

2017-11-24T13:28:47Z

Now that the SPDX tag is in all drivers/s390/ files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Sebastian Ott Cc: Peter Oberparleiter Cc: Julian Wiedmann Cc: Ursula Braun Cc: Cornelia Huck Cc: Halil Pasic Cc: "Paul E. McKenney" Signed-off-by: Greg Kroah-Hartman Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390: cio: add SPDX identifiers to the remaining files

2017-11-24T13:28:41Z

It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the drivers/s390/cio/ files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Sebastian Ott Cc: Peter Oberparleiter Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Cornelia Huck Cc: Dong Jia Shi Cc: Thomas Gleixner Cc: Kate Stewart Cc: Philippe Ombredanne Signed-off-by: Greg Kroah-Hartman Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/cio: introduce io_subchannel_type

2017-06-12T14:26:01Z

The sysfs attributes implemented by the vfio_ccw driver are also implemented by the io_subchannel driver. Move these into a device_type which is set by the css bus. Signed-off-by: Sebastian Ott Reviewed-by: Dong Jia Shi Reviewed-by: Cornelia Huck Signed-off-by: Martin Schwidefsky

s390/cio: remove unused struct member

2017-01-16T06:27:53Z

Remove an unused member of struct channel subsystem. Signed-off-by: Sebastian Ott Reviewed-by: Cornelia Huck Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky

s390/cio: export real cssid

2017-01-16T06:27:52Z

Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Reviewed-by: Cornelia Huck Signed-off-by: Martin Schwidefsky