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authorMartin Schwidefsky <schwidefsky@de.ibm.com>2008-12-25 13:38:36 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2008-12-25 13:38:55 +0100
commitb020632e40c3ed5e8c0c066d022672907e8401cf (patch)
treed7f805bd27e8378436fbba7e7457afbd10c22ed8 /arch/s390/kernel/vdso32
parentfc5243d98ac2575ad14a974b3c097e9ba874c03d (diff)
[S390] introduce vdso on s390
Add a vdso to speed up gettimeofday and clock_getres/clock_gettime for CLOCK_REALTIME/CLOCK_MONOTONIC. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/vdso32')
-rw-r--r--arch/s390/kernel/vdso32/Makefile55
-rw-r--r--arch/s390/kernel/vdso32/clock_getres.S39
-rw-r--r--arch/s390/kernel/vdso32/clock_gettime.S128
-rw-r--r--arch/s390/kernel/vdso32/gettimeofday.S82
-rw-r--r--arch/s390/kernel/vdso32/note.S12
-rw-r--r--arch/s390/kernel/vdso32/vdso32.lds.S138
-rw-r--r--arch/s390/kernel/vdso32/vdso32_wrapper.S13
7 files changed, 467 insertions, 0 deletions
diff --git a/arch/s390/kernel/vdso32/Makefile b/arch/s390/kernel/vdso32/Makefile
new file mode 100644
index 000000000000..ca78ad60ba24
--- /dev/null
+++ b/arch/s390/kernel/vdso32/Makefile
@@ -0,0 +1,55 @@
+# 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
+
+# Build rules
+
+targets := $(obj-vdso32) vdso32.so vdso32.so.dbg
+obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
+
+KBUILD_AFLAGS_31 := $(filter-out -m64,$(KBUILD_AFLAGS))
+KBUILD_AFLAGS_31 += -m31 -s
+
+KBUILD_CFLAGS_31 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_31 += -m31 -fPIC -shared -fno-common -fno-builtin
+KBUILD_CFLAGS_31 += -nostdlib -Wl,-soname=linux-vdso32.so.1 \
+ $(call ld-option, -Wl$(comma)--hash-style=sysv)
+
+$(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_31)
+$(targets:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_31)
+
+obj-y += vdso32_wrapper.o
+extra-y += vdso32.lds
+CPPFLAGS_vdso32.lds += -P -C -U$(ARCH)
+
+# Force dependency (incbin is bad)
+$(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
+
+# link rule for the .so file, .lds has to be first
+$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32)
+ $(call if_changed,vdso32ld)
+
+# strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+ $(call if_changed,objcopy)
+
+# assembly rules for the .S files
+$(obj-vdso32): %.o: %.S
+ $(call if_changed_dep,vdso32as)
+
+# actual build commands
+quiet_cmd_vdso32ld = VDSO32L $@
+ cmd_vdso32ld = $(CC) $(c_flags) -Wl,-T $^ -o $@
+quiet_cmd_vdso32as = VDSO32A $@
+ cmd_vdso32as = $(CC) $(a_flags) -c -o $@ $<
+
+# install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL $@
+ cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+
+vdso32.so: $(obj)/vdso32.so.dbg
+ @mkdir -p $(MODLIB)/vdso
+ $(call cmd,vdso_install)
+
+vdso_install: vdso32.so
diff --git a/arch/s390/kernel/vdso32/clock_getres.S b/arch/s390/kernel/vdso32/clock_getres.S
new file mode 100644
index 000000000000..9532c4e6a9d2
--- /dev/null
+++ b/arch/s390/kernel/vdso32/clock_getres.S
@@ -0,0 +1,39 @@
+/*
+ * Userland implementation of clock_getres() for 32 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ * Copyright IBM Corp. 2008
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+ .text
+ .align 4
+ .globl __kernel_clock_getres
+ .type __kernel_clock_getres,@function
+__kernel_clock_getres:
+ .cfi_startproc
+ chi %r2,CLOCK_REALTIME
+ je 0f
+ chi %r2,CLOCK_MONOTONIC
+ jne 3f
+0: ltr %r3,%r3
+ jz 2f /* res == NULL */
+ basr %r1,0
+1: l %r0,4f-1b(%r1)
+ xc 0(4,%r3),0(%r3) /* set tp->tv_sec to zero */
+ st %r0,4(%r3) /* store tp->tv_usec */
+2: lhi %r2,0
+ br %r14
+3: lhi %r1,__NR_clock_getres /* fallback to svc */
+ svc 0
+ br %r14
+4: .long CLOCK_REALTIME_RES
+ .cfi_endproc
+ .size __kernel_clock_getres,.-__kernel_clock_getres
diff --git a/arch/s390/kernel/vdso32/clock_gettime.S b/arch/s390/kernel/vdso32/clock_gettime.S
new file mode 100644
index 000000000000..4a98909a8310
--- /dev/null
+++ b/arch/s390/kernel/vdso32/clock_gettime.S
@@ -0,0 +1,128 @@
+/*
+ * Userland implementation of clock_gettime() for 32 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ * Copyright IBM Corp. 2008
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+ .text
+ .align 4
+ .globl __kernel_clock_gettime
+ .type __kernel_clock_gettime,@function
+__kernel_clock_gettime:
+ .cfi_startproc
+ basr %r5,0
+0: al %r5,21f-0b(%r5) /* get &_vdso_data */
+ chi %r2,CLOCK_REALTIME
+ je 10f
+ chi %r2,CLOCK_MONOTONIC
+ jne 19f
+
+ /* CLOCK_MONOTONIC */
+ ltr %r3,%r3
+ jz 9f /* tp == NULL */
+1: l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */
+ tml %r4,0x0001 /* pending update ? loop */
+ jnz 1b
+ stck 24(%r15) /* Store TOD clock */
+ lm %r0,%r1,24(%r15)
+ s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
+ sl %r1,__VDSO_XTIME_STAMP+4(%r5)
+ brc 3,2f
+ ahi %r0,-1
+2: mhi %r0,1000 /* cyc2ns(clock,cycle_delta) */
+ lr %r2,%r0
+ lhi %r0,1000
+ ltr %r1,%r1
+ mr %r0,%r0
+ jnm 3f
+ ahi %r0,1000
+3: alr %r0,%r2
+ srdl %r0,12
+ al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */
+ al %r1,__VDSO_XTIME_NSEC+4(%r5)
+ brc 12,4f
+ ahi %r0,1
+4: l %r2,__VDSO_XTIME_SEC+4(%r5)
+ al %r0,__VDSO_WTOM_NSEC(%r5) /* + wall_to_monotonic */
+ al %r1,__VDSO_WTOM_NSEC+4(%r5)
+ brc 12,5f
+ ahi %r0,1
+5: al %r2,__VDSO_WTOM_SEC+4(%r5)
+ cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */
+ jne 1b
+ basr %r5,0
+6: ltr %r0,%r0
+ jnz 7f
+ cl %r1,20f-6b(%r5)
+ jl 8f
+7: ahi %r2,1
+ sl %r1,20f-6b(%r5)
+ brc 3,6b
+ ahi %r0,-1
+ j 6b
+8: st %r2,0(%r3) /* store tp->tv_sec */
+ st %r1,4(%r3) /* store tp->tv_nsec */
+9: lhi %r2,0
+ br %r14
+
+ /* CLOCK_REALTIME */
+10: ltr %r3,%r3 /* tp == NULL */
+ jz 18f
+11: l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */
+ tml %r4,0x0001 /* pending update ? loop */
+ jnz 11b
+ stck 24(%r15) /* Store TOD clock */
+ lm %r0,%r1,24(%r15)
+ s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
+ sl %r1,__VDSO_XTIME_STAMP+4(%r5)
+ brc 3,12f
+ ahi %r0,-1
+12: mhi %r0,1000 /* cyc2ns(clock,cycle_delta) */
+ lr %r2,%r0
+ lhi %r0,1000
+ ltr %r1,%r1
+ mr %r0,%r0
+ jnm 13f
+ ahi %r0,1000
+13: alr %r0,%r2
+ srdl %r0,12
+ al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */
+ al %r1,__VDSO_XTIME_NSEC+4(%r5)
+ brc 12,14f
+ ahi %r0,1
+14: l %r2,__VDSO_XTIME_SEC+4(%r5)
+ cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */
+ jne 11b
+ basr %r5,0
+15: ltr %r0,%r0
+ jnz 16f
+ cl %r1,20f-15b(%r5)
+ jl 17f
+16: ahi %r2,1
+ sl %r1,20f-15b(%r5)
+ brc 3,15b
+ ahi %r0,-1
+ j 15b
+17: st %r2,0(%r3) /* store tp->tv_sec */
+ st %r1,4(%r3) /* store tp->tv_nsec */
+18: lhi %r2,0
+ br %r14
+
+ /* Fallback to system call */
+19: lhi %r1,__NR_clock_gettime
+ svc 0
+ br %r14
+
+20: .long 1000000000
+21: .long _vdso_data - 0b
+ .cfi_endproc
+ .size __kernel_clock_gettime,.-__kernel_clock_gettime
diff --git a/arch/s390/kernel/vdso32/gettimeofday.S b/arch/s390/kernel/vdso32/gettimeofday.S
new file mode 100644
index 000000000000..c32f29c3d70c
--- /dev/null
+++ b/arch/s390/kernel/vdso32/gettimeofday.S
@@ -0,0 +1,82 @@
+/*
+ * Userland implementation of gettimeofday() for 32 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ * Copyright IBM Corp. 2008
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+ .text
+ .align 4
+ .globl __kernel_gettimeofday
+ .type __kernel_gettimeofday,@function
+__kernel_gettimeofday:
+ .cfi_startproc
+ basr %r5,0
+0: al %r5,13f-0b(%r5) /* get &_vdso_data */
+1: ltr %r3,%r3 /* check if tz is NULL */
+ je 2f
+ mvc 0(8,%r3),__VDSO_TIMEZONE(%r5)
+2: ltr %r2,%r2 /* check if tv is NULL */
+ je 10f
+ l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */
+ tml %r4,0x0001 /* pending update ? loop */
+ jnz 1b
+ stck 24(%r15) /* Store TOD clock */
+ lm %r0,%r1,24(%r15)
+ s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
+ sl %r1,__VDSO_XTIME_STAMP+4(%r5)
+ brc 3,3f
+ ahi %r0,-1
+3: mhi %r0,1000 /* cyc2ns(clock,cycle_delta) */
+ st %r0,24(%r15)
+ lhi %r0,1000
+ ltr %r1,%r1
+ mr %r0,%r0
+ jnm 4f
+ ahi %r0,1000
+4: al %r0,24(%r15)
+ srdl %r0,12
+ al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */
+ al %r1,__VDSO_XTIME_NSEC+4(%r5)
+ brc 12,5f
+ ahi %r0,1
+5: mvc 24(4,%r15),__VDSO_XTIME_SEC+4(%r5)
+ cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */
+ jne 1b
+ l %r4,24(%r15) /* get tv_sec from stack */
+ basr %r5,0
+6: ltr %r0,%r0
+ jnz 7f
+ cl %r1,11f-6b(%r5)
+ jl 8f
+7: ahi %r4,1
+ sl %r1,11f-6b(%r5)
+ brc 3,6b
+ ahi %r0,-1
+ j 6b
+8: st %r4,0(%r2) /* store tv->tv_sec */
+ ltr %r1,%r1
+ m %r0,12f-6b(%r5)
+ jnm 9f
+ al %r0,12f-6b(%r5)
+9: srl %r0,6
+ st %r0,4(%r2) /* store tv->tv_usec */
+10: slr %r2,%r2
+ br %r14
+11: .long 1000000000
+12: .long 274877907
+13: .long _vdso_data - 0b
+ .cfi_endproc
+ .size __kernel_gettimeofday,.-__kernel_gettimeofday
diff --git a/arch/s390/kernel/vdso32/note.S b/arch/s390/kernel/vdso32/note.S
new file mode 100644
index 000000000000..79a071e4357e
--- /dev/null
+++ b/arch/s390/kernel/vdso32/note.S
@@ -0,0 +1,12 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+ .long LINUX_VERSION_CODE
+ELFNOTE_END
diff --git a/arch/s390/kernel/vdso32/vdso32.lds.S b/arch/s390/kernel/vdso32/vdso32.lds.S
new file mode 100644
index 000000000000..a8c379fa1247
--- /dev/null
+++ b/arch/s390/kernel/vdso32/vdso32.lds.S
@@ -0,0 +1,138 @@
+/*
+ * This is the infamous ld script for the 32 bits vdso
+ * library
+ */
+#include <asm/vdso.h>
+
+OUTPUT_FORMAT("elf32-s390", "elf32-s390", "elf32-s390")
+OUTPUT_ARCH(s390:31-bit)
+ENTRY(_start)
+
+SECTIONS
+{
+ . = VDSO32_LBASE + SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ .note : { *(.note.*) } :text :note
+
+ . = ALIGN(16);
+ .text : {
+ *(.text .stub .text.* .gnu.linkonce.t.*)
+ } :text
+ PROVIDE(__etext = .);
+ PROVIDE(_etext = .);
+ PROVIDE(etext = .);
+
+ /*
+ * Other stuff is appended to the text segment:
+ */
+ .rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+ .rodata1 : { *(.rodata1) }
+
+ .dynamic : { *(.dynamic) } :text :dynamic
+
+ .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
+ .eh_frame : { KEEP (*(.eh_frame)) } :text
+ .gcc_except_table : { *(.gcc_except_table .gcc_except_table.*) }
+
+ .rela.dyn ALIGN(8) : { *(.rela.dyn) }
+ .got ALIGN(8) : { *(.got .toc) }
+
+ _end = .;
+ PROVIDE(end = .);
+
+ /*
+ * Stabs debugging sections are here too.
+ */
+ .stab 0 : { *(.stab) }
+ .stabstr 0 : { *(.stabstr) }
+ .stab.excl 0 : { *(.stab.excl) }
+ .stab.exclstr 0 : { *(.stab.exclstr) }
+ .stab.index 0 : { *(.stab.index) }
+ .stab.indexstr 0 : { *(.stab.indexstr) }
+ .comment 0 : { *(.comment) }
+
+ /*
+ * DWARF debug sections.
+ * Symbols in the DWARF debugging sections are relative to the
+ * beginning of the section so we begin them at 0.
+ */
+ /* DWARF 1 */
+ .debug 0 : { *(.debug) }
+ .line 0 : { *(.line) }
+ /* GNU DWARF 1 extensions */
+ .debug_srcinfo 0 : { *(.debug_srcinfo) }
+ .debug_sfnames 0 : { *(.debug_sfnames) }
+ /* DWARF 1.1 and DWARF 2 */
+ .debug_aranges 0 : { *(.debug_aranges) }
+ .debug_pubnames 0 : { *(.debug_pubnames) }
+ /* DWARF 2 */
+ .debug_info 0 : { *(.debug_info .gnu.linkonce.wi.*) }
+ .debug_abbrev 0 : { *(.debug_abbrev) }
+ .debug_line 0 : { *(.debug_line) }
+ .debug_frame 0 : { *(.debug_frame) }
+ .debug_str 0 : { *(.debug_str) }
+ .debug_loc 0 : { *(.debug_loc) }
+ .debug_macinfo 0 : { *(.debug_macinfo) }
+ /* SGI/MIPS DWARF 2 extensions */
+ .debug_weaknames 0 : { *(.debug_weaknames) }
+ .debug_funcnames 0 : { *(.debug_funcnames) }
+ .debug_typenames 0 : { *(.debug_typenames) }
+ .debug_varnames 0 : { *(.debug_varnames) }
+ /* DWARF 3 */
+ .debug_pubtypes 0 : { *(.debug_pubtypes) }
+ .debug_ranges 0 : { *(.debug_ranges) }
+ .gnu.attributes 0 : { KEEP (*(.gnu.attributes)) }
+
+ . = ALIGN(4096);
+ PROVIDE(_vdso_data = .);
+
+ /DISCARD/ : {
+ *(.note.GNU-stack)
+ *(.branch_lt)
+ *(.data .data.* .gnu.linkonce.d.* .sdata*)
+ *(.bss .sbss .dynbss .dynsbss)
+ }
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME 0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+ eh_frame_hdr PT_GNU_EH_FRAME;
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+ VDSO_VERSION_STRING {
+ global:
+ /*
+ * Has to be there for the kernel to find
+ */
+ __kernel_gettimeofday;
+ __kernel_clock_gettime;
+ __kernel_clock_getres;
+
+ local: *;
+ };
+}
diff --git a/arch/s390/kernel/vdso32/vdso32_wrapper.S b/arch/s390/kernel/vdso32/vdso32_wrapper.S
new file mode 100644
index 000000000000..61639a89e70b
--- /dev/null
+++ b/arch/s390/kernel/vdso32/vdso32_wrapper.S
@@ -0,0 +1,13 @@
+#include <linux/init.h>
+#include <asm/page.h>
+
+ .section ".data.page_aligned"
+
+ .globl vdso32_start, vdso32_end
+ .balign PAGE_SIZE
+vdso32_start:
+ .incbin "arch/s390/kernel/vdso32/vdso32.so"
+ .balign PAGE_SIZE
+vdso32_end:
+
+ .previous