Commit 4efd417f authored by Vasily Gorbik's avatar Vasily Gorbik
Browse files

s390: raise minimum supported machine generation to z10 



Machine generations up to z9 (released in May 2006) have been officially
out of service for several years now (z9 end of service - January 31, 2019).
No distributions build kernels supporting those old machine generations
anymore, except Debian, which seems to pick the oldest supported
generation. The team supporting Debian on s390 has been notified about
the change.

Raising minimum supported machine generation to z10 helps to reduce
maintenance cost and effectively remove code, which is not getting
enough testing coverage due to lack of older hardware and distributions
support. Besides that this unblocks some optimization opportunities and
allows to use wider instruction set in asm files for future features
implementation. Due to this change spectre mitigation and usercopy
implementations could be drastically simplified and many newer instructions
could be converted from ".insn" encoding to instruction names.

Acked-by: default avatarIlya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 432b1cc7

arch/s390/Kconfig

+2 −66
Original line number Diff line number Diff line
@@ -120,7 +120,6 @@ config S390 
	select ARCH_WANT_IPC_PARSE_VERSION

	select BUILDTIME_TABLE_SORT

	select CLONE_BACKWARDS2

	select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES

	select DMA_OPS if PCI

	select DYNAMIC_FTRACE if FUNCTION_TRACER

	select GENERIC_ALLOCATOR
@@ -230,20 +229,8 @@ source "kernel/livepatch/Kconfig" 


menu "Processor type and features"



config HAVE_MARCH_Z900_FEATURES

	def_bool n



config HAVE_MARCH_Z990_FEATURES

	def_bool n

	select HAVE_MARCH_Z900_FEATURES



config HAVE_MARCH_Z9_109_FEATURES

	def_bool n

	select HAVE_MARCH_Z990_FEATURES



config HAVE_MARCH_Z10_FEATURES

	def_bool n

	select HAVE_MARCH_Z9_109_FEATURES



config HAVE_MARCH_Z196_FEATURES

	def_bool n
@@ -269,41 +256,13 @@ choice 
	prompt "Processor type"

	default MARCH_Z196



config MARCH_Z900

	bool "IBM zSeries model z800 and z900"

	select HAVE_MARCH_Z900_FEATURES

	depends on $(cc-option,-march=z900)

	help

	  Select this to enable optimizations for model z800/z900 (2064 and

	  2066 series). This will enable some optimizations that are not

	  available on older ESA/390 (31 Bit) only CPUs.



config MARCH_Z990

	bool "IBM zSeries model z890 and z990"

	select HAVE_MARCH_Z990_FEATURES

	depends on $(cc-option,-march=z990)

	help

	  Select this to enable optimizations for model z890/z990 (2084 and

	  2086 series). The kernel will be slightly faster but will not work

	  on older machines.



config MARCH_Z9_109

	bool "IBM System z9"

	select HAVE_MARCH_Z9_109_FEATURES

	depends on $(cc-option,-march=z9-109)

	help

	  Select this to enable optimizations for IBM System z9 (2094 and

	  2096 series). The kernel will be slightly faster but will not work

	  on older machines.



config MARCH_Z10

	bool "IBM System z10"

	select HAVE_MARCH_Z10_FEATURES

	depends on $(cc-option,-march=z10)

	help

	  Select this to enable optimizations for IBM System z10 (2097 and

	  2098 series). The kernel will be slightly faster but will not work

	  on older machines.

	  Select this to enable optimizations for IBM System z10 (2097 and 2098

	  series). This is the oldest machine generation currently supported.



config MARCH_Z196

	bool "IBM zEnterprise 114 and 196"
@@ -352,15 +311,6 @@ config MARCH_Z15 


endchoice



config MARCH_Z900_TUNE

	def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT



config MARCH_Z990_TUNE

	def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT



config MARCH_Z9_109_TUNE

	def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT



config MARCH_Z10_TUNE

	def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
@@ -396,21 +346,8 @@ config TUNE_DEFAULT 
	  Tune the generated code for the target processor for which the kernel

	  will be compiled.



config TUNE_Z900

	bool "IBM zSeries model z800 and z900"

	depends on $(cc-option,-mtune=z900)



config TUNE_Z990

	bool "IBM zSeries model z890 and z990"

	depends on $(cc-option,-mtune=z990)



config TUNE_Z9_109

	bool "IBM System z9"

	depends on $(cc-option,-mtune=z9-109)



config TUNE_Z10

	bool "IBM System z10"

	depends on $(cc-option,-mtune=z10)



config TUNE_Z196

	bool "IBM zEnterprise 114 and 196"
@@ -599,7 +536,6 @@ config EXPOLINE 
config EXPOLINE_EXTERN

	def_bool n

	depends on EXPOLINE

	depends on HAVE_MARCH_Z10_FEATURES

	depends on CC_IS_GCC && GCC_VERSION >= 110200

	depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC))

	prompt "Generate expolines as extern functions."

arch/s390/Makefile

+0 −6
Original line number Diff line number Diff line
@@ -36,9 +36,6 @@ CHECKFLAGS += -D__s390__ -D__s390x__ 


export LD_BFD



mflags-$(CONFIG_MARCH_Z900)   := -march=z900

mflags-$(CONFIG_MARCH_Z990)   := -march=z990

mflags-$(CONFIG_MARCH_Z9_109) := -march=z9-109

mflags-$(CONFIG_MARCH_Z10)    := -march=z10

mflags-$(CONFIG_MARCH_Z196)   := -march=z196

mflags-$(CONFIG_MARCH_ZEC12)  := -march=zEC12
@@ -51,9 +48,6 @@ export CC_FLAGS_MARCH := $(mflags-y) 
aflags-y += $(mflags-y)

cflags-y += $(mflags-y)



cflags-$(CONFIG_MARCH_Z900_TUNE)	+= -mtune=z900

cflags-$(CONFIG_MARCH_Z990_TUNE)	+= -mtune=z990

cflags-$(CONFIG_MARCH_Z9_109_TUNE)	+= -mtune=z9-109

cflags-$(CONFIG_MARCH_Z10_TUNE)		+= -mtune=z10

cflags-$(CONFIG_MARCH_Z196_TUNE)	+= -mtune=z196

cflags-$(CONFIG_MARCH_ZEC12_TUNE)	+= -mtune=zEC12

arch/s390/include/asm/bitops.h

+0 −12
Original line number Diff line number Diff line
@@ -256,8 +256,6 @@ static inline bool test_bit_inv(unsigned long nr, 
	return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);

}



#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES



/**

 * __flogr - find leftmost one

 * @word - The word to search
@@ -376,16 +374,6 @@ static inline int fls(unsigned int word) 
	return fls64(word);

}



#else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */



#include <asm-generic/bitops/__ffs.h>

#include <asm-generic/bitops/ffs.h>

#include <asm-generic/bitops/__fls.h>

#include <asm-generic/bitops/fls.h>

#include <asm-generic/bitops/fls64.h>



#endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */



#include <asm-generic/bitops/ffz.h>

#include <asm-generic/bitops/hweight.h>

#include <asm-generic/bitops/sched.h>

arch/s390/include/asm/lowcore.h

+3 −5
Original line number Diff line number Diff line
@@ -163,11 +163,9 @@ struct lowcore { 
	__u64	gmap;				/* 0x03d0 */

	__u8	pad_0x03d8[0x0400-0x03d8];	/* 0x03d8 */



	/* br %r1 trampoline */

	__u16	br_r1_trampoline;		/* 0x0400 */

	__u32	return_lpswe;			/* 0x0402 */

	__u32	return_mcck_lpswe;		/* 0x0406 */

	__u8	pad_0x040a[0x0e00-0x040a];	/* 0x040a */

	__u32	return_lpswe;			/* 0x0400 */

	__u32	return_mcck_lpswe;		/* 0x0404 */

	__u8	pad_0x040a[0x0e00-0x0408];	/* 0x0408 */



	/*

	 * 0xe00 contains the address of the IPL Parameter Information

arch/s390/include/asm/nospec-insn.h

+0 −34
Original line number Diff line number Diff line
@@ -10,8 +10,6 @@ 


#ifdef CC_USING_EXPOLINE



_LC_BR_R1 = __LC_BR_R1



/*

 * The expoline macros are used to create thunks in the same format

 * as gcc generates them. The 'comdat' section flag makes sure that
@@ -39,7 +37,6 @@ _LC_BR_R1 = __LC_BR_R1 
	.popsection

	.endm



#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES

	.macro __THUNK_PROLOG_BR r1,r2

	__THUNK_PROLOG_NAME __s390_indirect_jump_r\r1

	.endm
@@ -55,23 +52,6 @@ _LC_BR_R1 = __LC_BR_R1 
	.macro __THUNK_BRASL r1,r2,r3

	brasl	\r1,__s390_indirect_jump_r\r2

	.endm

#else

	.macro __THUNK_PROLOG_BR r1,r2

	__THUNK_PROLOG_NAME __s390_indirect_jump_r\r2\()use_r\r1

	.endm



	.macro __THUNK_EPILOG_BR r1,r2

	__THUNK_EPILOG_NAME __s390_indirect_jump_r\r2\()use_r\r1

	.endm



	.macro __THUNK_BR r1,r2

	jg	__s390_indirect_jump_r\r2\()use_r\r1

	.endm



	.macro __THUNK_BRASL r1,r2,r3

	brasl	\r1,__s390_indirect_jump_r\r3\()use_r\r2

	.endm

#endif



	.macro	__DECODE_RR expand,reg,ruse

	.set __decode_fail,1
@@ -112,22 +92,8 @@ _LC_BR_R1 = __LC_BR_R1 
	.endm



	.macro __THUNK_EX_BR reg,ruse

	# Be very careful when adding instructions to this macro!

	# The ALTERNATIVE replacement code has a .+10 which targets

	# the "br \reg" after the code has been patched.

#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES

	exrl	0,555f

	j	.

#else

	.ifc \reg,%r1

	ALTERNATIVE "ex %r0,_LC_BR_R1", ".insn ril,0xc60000000000,0,.+10", 35

	j	.

	.else

	larl	\ruse,555f

	ex	0,0(\ruse)

	j	.

	.endif

#endif

555:	br	\reg

	.endm