diff options
Diffstat (limited to 'arch/tile/kernel/vdso')
| -rw-r--r-- | arch/tile/kernel/vdso/Makefile | 118 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vdso.S | 28 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vdso.lds.S | 89 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vdso32.S | 28 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vgettimeofday.c | 198 | ||||
| -rw-r--r-- | arch/tile/kernel/vdso/vrt_sigreturn.S | 30 |
6 files changed, 491 insertions, 0 deletions
diff --git a/arch/tile/kernel/vdso/Makefile b/arch/tile/kernel/vdso/Makefile new file mode 100644 index 000000000..a025f63d5 --- /dev/null +++ b/arch/tile/kernel/vdso/Makefile @@ -0,0 +1,118 @@ +# Symbols present in the vdso +vdso-syms = rt_sigreturn gettimeofday + +# Files to link into the vdso +obj-vdso = $(patsubst %, v%.o, $(vdso-syms)) + +# Build rules +targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds +obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) + +# vdso32 is only for tilegx -m32 compat task. +VDSO32-$(CONFIG_COMPAT) := y + +obj-y += vdso.o +obj-$(VDSO32-y) += vdso32.o +extra-y += vdso.lds +CPPFLAGS_vdso.lds += -P -C -U$(ARCH) + +# vDSO code runs in userspace and -pg doesn't help with profiling anyway. +CFLAGS_REMOVE_vdso.o = -pg +CFLAGS_REMOVE_vdso32.o = -pg +CFLAGS_REMOVE_vrt_sigreturn.o = -pg +CFLAGS_REMOVE_vrt_sigreturn32.o = -pg +CFLAGS_REMOVE_vgettimeofday.o = -pg +CFLAGS_REMOVE_vgettimeofday32.o = -pg + +ifdef CONFIG_FEEDBACK_COLLECT +# vDSO code runs in userspace, not collecting feedback data. +CFLAGS_REMOVE_vdso.o = -ffeedback-generate +CFLAGS_REMOVE_vdso32.o = -ffeedback-generate +CFLAGS_REMOVE_vrt_sigreturn.o = -ffeedback-generate +CFLAGS_REMOVE_vrt_sigreturn32.o = -ffeedback-generate +CFLAGS_REMOVE_vgettimeofday.o = -ffeedback-generate +CFLAGS_REMOVE_vgettimeofday32.o = -ffeedback-generate +endif + +# Disable gcov profiling for VDSO code +GCOV_PROFILE := n + +# Force dependency +$(obj)/vdso.o: $(obj)/vdso.so + +# link rule for the .so file, .lds has to be first +SYSCFLAGS_vdso.so.dbg = $(c_flags) +$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) + $(call if_changed,vdsold) + + +# We also create a special relocatable object that should mirror the symbol +# table and layout of the linked DSO. With ld -R we can then refer to +# these symbols in the kernel code rather than hand-coded addresses. +extra-y += vdso-syms.o +$(obj)/built-in.o: $(obj)/vdso-syms.o +$(obj)/built-in.o: ld_flags += -R $(obj)/vdso-syms.o + +SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ + $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) +SYSCFLAGS_vdso_syms.o = -r +$(obj)/vdso-syms.o: $(src)/vdso.lds $(obj)/vrt_sigreturn.o FORCE + $(call if_changed,vdsold) + + +# strip rule for the .so file +$(obj)/%.so: OBJCOPYFLAGS := -S +$(obj)/%.so: $(obj)/%.so.dbg FORCE + $(call if_changed,objcopy) + +# actual build commands +# The DSO images are built using a special linker script +# Add -lgcc so tilepro gets static muldi3 and lshrdi3 definitions. +# Make sure only to export the intended __vdso_xxx symbol offsets. +quiet_cmd_vdsold = VDSOLD $@ + cmd_vdsold = $(CC) $(KCFLAGS) -nostdlib $(SYSCFLAGS_$(@F)) \ + -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp -lgcc && \ + $(CROSS_COMPILE)objcopy \ + $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ + +# install commands for the unstripped file +quiet_cmd_vdso_install = INSTALL $@ + cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ + +vdso.so: $(obj)/vdso.so.dbg + @mkdir -p $(MODLIB)/vdso + $(call cmd,vdso_install) + +vdso32.so: $(obj)/vdso32.so.dbg + $(call cmd,vdso_install) + +vdso_install: vdso.so +vdso32_install: vdso32.so + + +KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) +KBUILD_AFLAGS_32 += -m32 -s +KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS)) +KBUILD_CFLAGS_32 += -m32 -fPIC -shared + +obj-vdso32 = $(patsubst %, v%32.o, $(vdso-syms)) +obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32)) + +targets += $(obj-vdso32) vdso32.so vdso32.so.dbg + +$(obj-vdso32:%=%): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32) +$(obj-vdso32:%=%): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32) + +$(obj)/vgettimeofday32.o: $(obj)/vgettimeofday.c + $(call if_changed_rule,cc_o_c) + +$(obj)/vrt_sigreturn32.o: $(obj)/vrt_sigreturn.S + $(call if_changed,as_o_S) + +# Force dependency +$(obj)/vdso32.o: $(obj)/vdso32.so + +SYSCFLAGS_vdso32.so.dbg = -m32 -shared -s -Wl,-soname=linux-vdso32.so.1 \ + $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) +$(obj)/vdso32.so.dbg: $(src)/vdso.lds $(obj-vdso32) + $(call if_changed,vdsold) diff --git a/arch/tile/kernel/vdso/vdso.S b/arch/tile/kernel/vdso/vdso.S new file mode 100644 index 000000000..3467adb41 --- /dev/null +++ b/arch/tile/kernel/vdso/vdso.S @@ -0,0 +1,28 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <asm/page.h> + + __PAGE_ALIGNED_DATA + + .global vdso_start, vdso_end + .align PAGE_SIZE +vdso_start: + .incbin "arch/tile/kernel/vdso/vdso.so" + .align PAGE_SIZE +vdso_end: + + .previous diff --git a/arch/tile/kernel/vdso/vdso.lds.S b/arch/tile/kernel/vdso/vdso.lds.S new file mode 100644 index 000000000..731529f3f --- /dev/null +++ b/arch/tile/kernel/vdso/vdso.lds.S @@ -0,0 +1,89 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#define VDSO_VERSION_STRING LINUX_2.6 + + +OUTPUT_ARCH(tile) + +/* The ELF entry point can be used to set the AT_SYSINFO value. */ +ENTRY(__vdso_rt_sigreturn); + + +SECTIONS +{ + . = 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 + .dynamic : { *(.dynamic) } :text :dynamic + + .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr + .eh_frame : { KEEP (*(.eh_frame)) } :text + + .rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) } + + /* + * This linker script is used both with -r and with -shared. + * For the layouts to match, we need to skip more than enough + * space for the dynamic symbol table et al. If this amount + * is insufficient, ld -shared will barf. Just increase it here. + */ + . = 0x1000; + .text : { *(.text .text.*) } :text + + .data : { + *(.got.plt) *(.got) + *(.data .data.* .gnu.linkonce.d.*) + *(.dynbss) + *(.bss .bss.* .gnu.linkonce.b.*) + } +} + + +/* + * 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 FLAGS(5) FILEHDR PHDRS; /* 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 userland symbols we export from the vDSO. + */ +VERSION +{ + VDSO_VERSION_STRING { + global: + __vdso_rt_sigreturn; + __vdso_gettimeofday; + gettimeofday; + __vdso_clock_gettime; + clock_gettime; + local:*; + }; +} diff --git a/arch/tile/kernel/vdso/vdso32.S b/arch/tile/kernel/vdso/vdso32.S new file mode 100644 index 000000000..1d1ac3257 --- /dev/null +++ b/arch/tile/kernel/vdso/vdso32.S @@ -0,0 +1,28 @@ +/* + * Copyright 2013 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <asm/page.h> + + __PAGE_ALIGNED_DATA + + .global vdso32_start, vdso32_end + .align PAGE_SIZE +vdso32_start: + .incbin "arch/tile/kernel/vdso/vdso32.so" + .align PAGE_SIZE +vdso32_end: + + .previous diff --git a/arch/tile/kernel/vdso/vgettimeofday.c b/arch/tile/kernel/vdso/vgettimeofday.c new file mode 100644 index 000000000..8bb21eda0 --- /dev/null +++ b/arch/tile/kernel/vdso/vgettimeofday.c @@ -0,0 +1,198 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#define VDSO_BUILD /* avoid some shift warnings for -m32 in <asm/page.h> */ +#include <linux/time.h> +#include <asm/timex.h> +#include <asm/unistd.h> +#include <asm/vdso.h> + +#if CHIP_HAS_SPLIT_CYCLE() +static inline cycles_t get_cycles_inline(void) +{ + unsigned int high = __insn_mfspr(SPR_CYCLE_HIGH); + unsigned int low = __insn_mfspr(SPR_CYCLE_LOW); + unsigned int high2 = __insn_mfspr(SPR_CYCLE_HIGH); + + while (unlikely(high != high2)) { + low = __insn_mfspr(SPR_CYCLE_LOW); + high = high2; + high2 = __insn_mfspr(SPR_CYCLE_HIGH); + } + + return (((cycles_t)high) << 32) | low; +} +#define get_cycles get_cycles_inline +#endif + +struct syscall_return_value { + long value; + long error; +}; + +/* + * Find out the vDSO data page address in the process address space. + */ +inline unsigned long get_datapage(void) +{ + unsigned long ret; + + /* vdso data page located in the 2nd vDSO page. */ + asm volatile ("lnk %0" : "=r"(ret)); + ret &= ~(PAGE_SIZE - 1); + ret += PAGE_SIZE; + + return ret; +} + +static inline u64 vgetsns(struct vdso_data *vdso) +{ + return ((get_cycles() - vdso->cycle_last) & vdso->mask) * vdso->mult; +} + +static inline int do_realtime(struct vdso_data *vdso, struct timespec *ts) +{ + unsigned count; + u64 ns; + + do { + count = read_seqcount_begin(&vdso->tb_seq); + ts->tv_sec = vdso->wall_time_sec; + ns = vdso->wall_time_snsec; + ns += vgetsns(vdso); + ns >>= vdso->shift; + } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + +static inline int do_monotonic(struct vdso_data *vdso, struct timespec *ts) +{ + unsigned count; + u64 ns; + + do { + count = read_seqcount_begin(&vdso->tb_seq); + ts->tv_sec = vdso->monotonic_time_sec; + ns = vdso->monotonic_time_snsec; + ns += vgetsns(vdso); + ns >>= vdso->shift; + } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + +static inline int do_realtime_coarse(struct vdso_data *vdso, + struct timespec *ts) +{ + unsigned count; + + do { + count = read_seqcount_begin(&vdso->tb_seq); + ts->tv_sec = vdso->wall_time_coarse_sec; + ts->tv_nsec = vdso->wall_time_coarse_nsec; + } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count))); + + return 0; +} + +static inline int do_monotonic_coarse(struct vdso_data *vdso, + struct timespec *ts) +{ + unsigned count; + + do { + count = read_seqcount_begin(&vdso->tb_seq); + ts->tv_sec = vdso->monotonic_time_coarse_sec; + ts->tv_nsec = vdso->monotonic_time_coarse_nsec; + } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count))); + + return 0; +} + +struct syscall_return_value __vdso_gettimeofday(struct timeval *tv, + struct timezone *tz) +{ + struct syscall_return_value ret = { 0, 0 }; + unsigned count; + struct vdso_data *vdso = (struct vdso_data *)get_datapage(); + + /* The use of the timezone is obsolete, normally tz is NULL. */ + if (unlikely(tz != NULL)) { + do { + count = read_seqcount_begin(&vdso->tz_seq); + tz->tz_minuteswest = vdso->tz_minuteswest; + tz->tz_dsttime = vdso->tz_dsttime; + } while (unlikely(read_seqcount_retry(&vdso->tz_seq, count))); + } + + if (unlikely(tv == NULL)) + return ret; + + do_realtime(vdso, (struct timespec *)tv); + tv->tv_usec /= 1000; + + return ret; +} + +int gettimeofday(struct timeval *tv, struct timezone *tz) + __attribute__((weak, alias("__vdso_gettimeofday"))); + +static struct syscall_return_value vdso_fallback_gettime(long clock, + struct timespec *ts) +{ + struct syscall_return_value ret; + __asm__ __volatile__ ( + "swint1" + : "=R00" (ret.value), "=R01" (ret.error) + : "R10" (__NR_clock_gettime), "R00" (clock), "R01" (ts) + : "r2", "r3", "r4", "r5", "r6", "r7", + "r8", "r9", "r11", "r12", "r13", "r14", "r15", + "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23", + "r24", "r25", "r26", "r27", "r28", "r29", "memory"); + return ret; +} + +struct syscall_return_value __vdso_clock_gettime(clockid_t clock, + struct timespec *ts) +{ + struct vdso_data *vdso = (struct vdso_data *)get_datapage(); + struct syscall_return_value ret = { 0, 0 }; + + switch (clock) { + case CLOCK_REALTIME: + do_realtime(vdso, ts); + return ret; + case CLOCK_MONOTONIC: + do_monotonic(vdso, ts); + return ret; + case CLOCK_REALTIME_COARSE: + do_realtime_coarse(vdso, ts); + return ret; + case CLOCK_MONOTONIC_COARSE: + do_monotonic_coarse(vdso, ts); + return ret; + default: + return vdso_fallback_gettime(clock, ts); + } +} + +int clock_gettime(clockid_t clock, struct timespec *ts) + __attribute__((weak, alias("__vdso_clock_gettime"))); diff --git a/arch/tile/kernel/vdso/vrt_sigreturn.S b/arch/tile/kernel/vdso/vrt_sigreturn.S new file mode 100644 index 000000000..6326caf4a --- /dev/null +++ b/arch/tile/kernel/vdso/vrt_sigreturn.S @@ -0,0 +1,30 @@ +/* + * Copyright 2012 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/linkage.h> +#include <arch/abi.h> +#include <asm/unistd.h> + +/* + * Note that libc has a copy of this function that it uses to compare + * against the PC when a stack backtrace ends, so if this code is + * changed, the libc implementation(s) should also be updated. + */ +ENTRY(__vdso_rt_sigreturn) + moveli TREG_SYSCALL_NR_NAME, __NR_rt_sigreturn + swint1 + /* We don't use ENDPROC to avoid tagging this symbol as FUNC, + * which confuses the perf tool. + */ + END(__vdso_rt_sigreturn) |