kernel.git/drivers/s390/char/sclp.h, branch master

s390: Use inline qualifier for all EX_TABLE and ALTERNATIVE inline assemblies

2025-03-18T16:13:51Z

Use asm_inline for all inline assemblies which make use of the EX_TABLE or ALTERNATIVE macros. These macros expand to many lines and the compiler assumes the number of lines within an inline assembly is the same as the number of instructions within an inline assembly. This has an effect on inlining and loop unrolling decisions. In order to avoid incorrect assumptions use asm_inline, which tells the compiler that an inline assembly has the smallest possible size. In order to avoid confusion when asm_inline should be used or not, since a couple of inline assemblies are quite large: the rule is to always use asm_inline whenever the EX_TABLE or ALTERNATIVE macro is used. In specific cases there may be reasons to not follow this guideline, but that should be documented with the corresponding code. Using the inline qualifier everywhere has only a small effect on the kernel image size: add/remove: 0/10 grow/shrink: 19/8 up/down: 1492/-1858 (-366) The only location where this seems to matter is load_unaligned_zeropad() from word-at-a-time.h where the compiler inlines more functions within the dcache code, which is indeed code where performance matters. Suggested-by: Juergen Christ Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390: Convert MACHINE_IS_[LPAR|VM|KVM], etc, machine_is_[lpar|vm|kvm]()

2025-03-04T16:18:07Z

Move machine type detection to the decompressor and use static branches to implement and use machine_is_[lpar|vm|kvm]() instead of a runtime check via MACHINE_IS_[LPAR|VM|KVM]. Reviewed-by: Vasily Gorbik Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

Merge branch 'pci-device-recovery' into features

2024-12-18T15:06:24Z

Niklas Schnelle says: =================== This patch series enhances the introspectability of the PCI device recovery for firmware. Until now when Linux performs recovery in response to a firmware error report. For example, until now firmware debug data would have no indication if the recovery was successfull or if it failed, for example due to KVM pass-through. Improve on this by reporting recovery status as well as some debug information such as device driver name and s390dbf/pci_msg/sprintf logs via the SCLP Write Event Data Action Qualifier 2 (Log Data provided) mechanism. =================== Signed-off-by: Alexander Gordeev

s390/diag324: Retrieve power readings via diag 0x324

2024-12-17T11:46:14Z

Retrieve electrical power readings for resources in a computing environment via diag 0x324. diag 0x324 stores the power readings in the power information block (pib). Provide power readings from pib via diag324 ioctl interface. diag324 ioctl provides new pib to the user only if the threshold time has passed since the last call. Otherwise, cache data is returned. When there are no active readers, cleanup of pib buffer is performed. Reviewed-by: Heiko Carstens Signed-off-by: Sumanth Korikkar Signed-off-by: Alexander Gordeev

s390/pci: Report PCI error recovery results via SCLP

2024-12-16T15:14:26Z

Add a mechanism with which the status of PCI error recovery runs is reported to the platform. Together with the status supply additional information that may aid in problem determination. Reviewed-by: Halil Pasic Signed-off-by: Niklas Schnelle Signed-off-by: Alexander Gordeev

s390/sclp: Convert to use flag output macros

2024-11-13T13:31:34Z

Use flag output macros in inline asm to allow for better code generation if the compiler has support for the flag output constraint. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens

s390/sclp: replace zero-length array with flexible-array member

2023-04-13T15:36:29Z

There are numerous patches which convert zero-length arrays with a flexible-array member. Convert the remaining s390 occurrences. Suggested-by: Gustavo A. R. Silva Link: https://github.com/KSPP/linux/issues/78 Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/sclp: use kstrobool() to parse sclp_con_drop parameter

2022-11-29T13:17:03Z

Use kstrobool() to parse sclp_con_drop parameter. This way handling of valid values for the sclp_con_drop parameter is identical to the con3215_drop parameter. In particular this allows to pass values like "yes" and "true", which was not possible before. Reviewed-by: Peter Oberparleiter Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/extable: move EX_TABLE define to asm-extable.h

2022-03-07T23:33:00Z

Follow arm64 and riscv and move the EX_TABLE define to asm-extable.h which is a lot less generic than the current linkage.h. Also make sure that all files which contain EX_TABLE usages actually include the new header file. This should make sure that the files always compile and there won't be any random compile breakage due to other header file dependencies. Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/sclp: sort out physical vs virtual pointers usage

2021-10-26T13:21:28Z

Provide physical addresses whenever the hardware interface expects it or a 32-bit value used for tracking. Variable sclp_early_sccb gets initialized in the decompressor and points to an address in physcal memory. Yet, it is used as virtual memory pointer and therefore should be converted. Note, the other two __bootdata variables sclp_info_sccb and sclp_info_sccb_valid contain plain data, but no pointers and do need any special care. Reviewed-by: Heiko Carstens Signed-off-by: Alexander Gordeev Signed-off-by: Vasily Gorbik