aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/vdso32
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2016-01-13 13:16:16 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-13 13:16:16 -0800
commitcbd88cd4c07f9361914ab7fd7e21c9227986fe68 (patch)
tree8bc448d73f93f10ebd34ef38c911b06359000ed0 /arch/s390/kernel/vdso32
parentMerge tag 'please-pull-fixefi' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux (diff)
parents390/sclp: fix possible control register corruption (diff)
downloadlinux-dev-cbd88cd4c07f9361914ab7fd7e21c9227986fe68.tar.xz
linux-dev-cbd88cd4c07f9361914ab7fd7e21c9227986fe68.zip
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky: "Among the traditional bug fixes and cleanups are some improvements: - A tool to generated the facility lists, generating the bit fields by hand has been a source of bugs in the past - The spinlock loop is reordered to avoid bursts of hypervisor calls - Add support for the open-for-business interface to the service element - The get_cpu call is added to the vdso - A set of tracepoints is defined for the common I/O layer - The deprecated sclp_cpi module is removed - Update default configuration" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (56 commits) s390/sclp: fix possible control register corruption s390: fix normalization bug in exception table sorting s390/configs: update default configurations s390/vdso: optimize getcpu system call s390: drop smp_mb in vdso_init s390: rename struct _lowcore to struct lowcore s390/mem_detect: use unsigned longs s390/ptrace: get rid of long longs in psw_bits s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK s390/Kconfig: remove pointless 64 bit dependencies s390/dasd: fix failfast for disconnected devices s390/con3270: testing return kzalloc retval s390/hmcdrv: constify hmcdrv_ftp_ops structs s390/cio: add NULL test s390/cio: Change I/O instructions from inline to normal functions s390/cio: Introduce common I/O layer tracepoints s390/cio: Consolidate inline assemblies and related data definitions s390/cio: Fix incorrect xsch opcode specification s390/cio: Remove unused inline assemblies ...
Diffstat (limited to 'arch/s390/kernel/vdso32')
-rw-r--r--arch/s390/kernel/vdso32/Makefile2
-rw-r--r--arch/s390/kernel/vdso32/getcpu.S43
-rw-r--r--arch/s390/kernel/vdso32/vdso32.lds.S1
3 files changed, 45 insertions, 1 deletions
diff --git a/arch/s390/kernel/vdso32/Makefile b/arch/s390/kernel/vdso32/Makefile
index ee8a18e50a25..f9c459586649 100644
--- a/arch/s390/kernel/vdso32/Makefile
+++ b/arch/s390/kernel/vdso32/Makefile
@@ -1,6 +1,6 @@
# List of files in the vdso, has to be asm only for now
-obj-vdso32 = gettimeofday.o clock_getres.o clock_gettime.o note.o
+obj-vdso32 = gettimeofday.o clock_getres.o clock_gettime.o note.o getcpu.o
# Build rules
diff --git a/arch/s390/kernel/vdso32/getcpu.S b/arch/s390/kernel/vdso32/getcpu.S
new file mode 100644
index 000000000000..c1ed0b72030f
--- /dev/null
+++ b/arch/s390/kernel/vdso32/getcpu.S
@@ -0,0 +1,43 @@
+/*
+ * Userland implementation of getcpu() for 32 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+
+ .text
+ .align 4
+ .globl __kernel_getcpu
+ .type __kernel_getcpu,@function
+__kernel_getcpu:
+ .cfi_startproc
+ ear %r1,%a4
+ lhi %r4,1
+ sll %r4,24
+ sar %a4,%r4
+ la %r4,0
+ epsw %r0,0
+ sacf 512
+ l %r5,__VDSO_CPU_NR(%r4)
+ l %r4,__VDSO_NODE_ID(%r4)
+ tml %r0,0x4000
+ jo 1f
+ tml %r0,0x8000
+ jno 0f
+ sacf 256
+ j 1f
+0: sacf 0
+1: sar %a4,%r1
+ ltr %r2,%r2
+ jz 2f
+ st %r5,0(%r2)
+2: ltr %r3,%r3
+ jz 3f
+ st %r4,0(%r3)
+3: lhi %r2,0
+ br %r14
+ .cfi_endproc
+ .size __kernel_getcpu,.-__kernel_getcpu
diff --git a/arch/s390/kernel/vdso32/vdso32.lds.S b/arch/s390/kernel/vdso32/vdso32.lds.S
index a8c379fa1247..8f048c2d6d13 100644
--- a/arch/s390/kernel/vdso32/vdso32.lds.S
+++ b/arch/s390/kernel/vdso32/vdso32.lds.S
@@ -132,6 +132,7 @@ VERSION
__kernel_gettimeofday;
__kernel_clock_gettime;
__kernel_clock_getres;
+ __kernel_getcpu;
local: *;
};