tile: implement gettimeofday() via vDSO
This change creates the framework for vDSO calls, makes the existing rt_sigreturn() mechanism use it, and adds a fast gettimeofday(). Now that we need to expose the vDSO address to userspace, we add AT_SYSINFO_EHDR to the set of aux entries provided to userspace. (You can disable any extra vDSO support by booting with vdso=0, but the rt_sigreturn vDSO page will still be provided.) Note that glibc has supported the tile vDSO since release 2.17. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This commit is contained in:
Chris Metcalf
parent
0c1d1917c5
commit
4a556f4f56
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@ -64,6 +64,9 @@ config HUGETLB_SUPER_PAGES
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depends on HUGETLB_PAGE && TILEGX
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def_bool y
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config GENERIC_TIME_VSYSCALL
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def_bool y
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# FIXME: tilegx can implement a more efficient rwsem.
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config RWSEM_GENERIC_SPINLOCK
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def_bool y
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@ -132,6 +132,11 @@ extern int dump_task_regs(struct task_struct *, elf_gregset_t *);
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struct linux_binprm;
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extern int arch_setup_additional_pages(struct linux_binprm *bprm,
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int executable_stack);
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#define ARCH_DLINFO \
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do { \
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NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_BASE); \
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} while (0)
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#ifdef CONFIG_COMPAT
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#define COMPAT_ELF_PLATFORM "tilegx-m32"
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@ -22,6 +22,7 @@ struct mm_context {
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* semaphore but atomically, but it is conservatively set.
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*/
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unsigned long priority_cached;
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unsigned long vdso_base;
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};
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typedef struct mm_context mm_context_t;
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@ -38,6 +38,12 @@
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#define PAGE_MASK (~(PAGE_SIZE - 1))
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#define HPAGE_MASK (~(HPAGE_SIZE - 1))
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/*
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* We do define AT_SYSINFO_EHDR to support vDSO,
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* but don't use the gate mechanism.
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*/
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#define __HAVE_ARCH_GATE_AREA 1
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/*
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* If the Kconfig doesn't specify, set a maximum zone order that
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* is enough so that we can create huge pages from small pages given
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@ -246,7 +252,7 @@ static inline __attribute_const__ int get_order(unsigned long size)
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#endif /* __tilegx__ */
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#ifndef __ASSEMBLY__
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#if !defined(__ASSEMBLY__) && !defined(VDSO_BUILD)
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#ifdef CONFIG_HIGHMEM
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@ -180,10 +180,10 @@ struct thread_struct {
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#define TASK_SIZE TASK_SIZE_MAX
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#endif
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/* We provide a minimal "vdso" a la x86; just the sigreturn code for now. */
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#define VDSO_BASE (TASK_SIZE - PAGE_SIZE)
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#define VDSO_BASE ((unsigned long)current->active_mm->context.vdso_base)
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#define VDSO_SYM(x) (VDSO_BASE + (unsigned long)(x))
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#define STACK_TOP VDSO_BASE
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#define STACK_TOP TASK_SIZE
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/* STACK_TOP_MAX is used temporarily in execve and should not check COMPAT. */
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#define STACK_TOP_MAX TASK_SIZE_MAX
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@ -25,6 +25,10 @@ extern char _sinitdata[], _einitdata[];
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/* Write-once data is writable only till the end of initialization. */
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extern char __w1data_begin[], __w1data_end[];
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extern char vdso_start[], vdso_end[];
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#ifdef CONFIG_COMPAT
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extern char vdso32_start[], vdso32_end[];
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#endif
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/* Not exactly sections, but PC comparison points in the code. */
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extern char __rt_sigreturn[], __rt_sigreturn_end[];
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@ -0,0 +1,49 @@
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/*
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* Copyright 2012 Tilera Corporation. All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation, version 2.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
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* NON INFRINGEMENT. See the GNU General Public License for
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* more details.
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*/
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#ifndef __TILE_VDSO_H__
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#define __TILE_VDSO_H__
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#include <linux/types.h>
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/*
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* Note about the vdso_data structure:
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*
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* NEVER USE THEM IN USERSPACE CODE DIRECTLY. The layout of the
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* structure is supposed to be known only to the function in the vdso
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* itself and may change without notice.
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*/
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struct vdso_data {
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__u64 tz_update_count; /* Timezone atomicity ctr */
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__u64 tb_update_count; /* Timebase atomicity ctr */
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__u64 xtime_tod_stamp; /* TOD clock for xtime */
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__u64 xtime_clock_sec; /* Kernel time second */
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__u64 xtime_clock_nsec; /* Kernel time nanosecond */
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__u64 wtom_clock_sec; /* Wall to monotonic clock second */
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__u64 wtom_clock_nsec; /* Wall to monotonic clock nanosecond */
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__u32 mult; /* Cycle to nanosecond multiplier */
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__u32 shift; /* Cycle to nanosecond divisor (power of two) */
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__u32 tz_minuteswest; /* Minutes west of Greenwich */
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__u32 tz_dsttime; /* Type of dst correction */
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};
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extern struct vdso_data *vdso_data;
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/* __vdso_rt_sigreturn is defined with the addresses in the vdso page. */
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extern void __vdso_rt_sigreturn(void);
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extern int setup_vdso_pages(void);
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#endif /* __TILE_VDSO_H__ */
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@ -15,6 +15,7 @@
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#ifndef _ASM_TILE_AUXVEC_H
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#define _ASM_TILE_AUXVEC_H
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/* No extensions to auxvec */
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/* The vDSO location. */
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#define AT_SYSINFO_EHDR 33
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#endif /* _ASM_TILE_AUXVEC_H */
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@ -6,7 +6,7 @@ extra-y := vmlinux.lds head_$(BITS).o
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obj-y := backtrace.o entry.o irq.o messaging.o \
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pci-dma.o proc.o process.o ptrace.o reboot.o \
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setup.o signal.o single_step.o stack.o sys.o \
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sysfs.o time.o traps.o unaligned.o \
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sysfs.o time.o traps.o unaligned.o vdso.o \
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intvec_$(BITS).o regs_$(BITS).o tile-desc_$(BITS).o
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obj-$(CONFIG_HARDWALL) += hardwall.o
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@ -21,3 +21,5 @@ else
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obj-$(CONFIG_PCI) += pci.o
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endif
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obj-$(CONFIG_TILE_USB) += usb.o
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obj-y += vdso/
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@ -32,6 +32,7 @@
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#include <asm/ucontext.h>
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#include <asm/sigframe.h>
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#include <asm/syscalls.h>
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#include <asm/vdso.h>
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#include <arch/interrupts.h>
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struct compat_ucontext {
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@ -227,7 +228,7 @@ int compat_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
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if (err)
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goto give_sigsegv;
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restorer = VDSO_BASE;
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restorer = VDSO_SYM(&__vdso_rt_sigreturn);
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if (ka->sa.sa_flags & SA_RESTORER)
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restorer = ptr_to_compat_reg(ka->sa.sa_restorer);
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@ -27,22 +27,6 @@ STD_ENTRY(current_text_addr)
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{ move r0, lr; jrp lr }
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STD_ENDPROC(current_text_addr)
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/*
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* We don't run this function directly, but instead copy it to a page
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* we map into every user process. See vdso_setup().
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*
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* Note that libc has a copy of this function that it uses to compare
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* against the PC when a stack backtrace ends, so if this code is
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* changed, the libc implementation(s) should also be updated.
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*/
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.pushsection .data
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ENTRY(__rt_sigreturn)
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moveli TREG_SYSCALL_NR_NAME,__NR_rt_sigreturn
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swint1
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ENDPROC(__rt_sigreturn)
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ENTRY(__rt_sigreturn_end)
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.popsection
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STD_ENTRY(dump_stack)
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{ move r2, lr; lnk r1 }
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{ move r4, r52; addli r1, r1, dump_stack - . }
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@ -33,6 +33,7 @@
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#include <asm/ucontext.h>
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#include <asm/sigframe.h>
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#include <asm/syscalls.h>
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#include <asm/vdso.h>
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#include <arch/interrupts.h>
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#define DEBUG_SIG 0
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@ -190,7 +191,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
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if (err)
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goto give_sigsegv;
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restorer = VDSO_BASE;
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restorer = VDSO_SYM(&__vdso_rt_sigreturn);
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if (ka->sa.sa_flags & SA_RESTORER)
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restorer = (unsigned long) ka->sa.sa_restorer;
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@ -29,6 +29,7 @@
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#include <asm/switch_to.h>
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#include <asm/sigframe.h>
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#include <asm/stack.h>
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#include <asm/vdso.h>
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#include <arch/abi.h>
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#include <arch/interrupts.h>
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@ -119,7 +120,7 @@ static struct pt_regs *valid_fault_handler(struct KBacktraceIterator* kbt)
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/* Is the pc pointing to a sigreturn trampoline? */
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static int is_sigreturn(unsigned long pc)
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{
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return (pc == VDSO_BASE);
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return current->mm && (pc == VDSO_SYM(&__vdso_rt_sigreturn));
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}
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/* Return a pt_regs pointer for a valid signal handler frame */
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@ -128,7 +129,7 @@ static struct pt_regs *valid_sigframe(struct KBacktraceIterator* kbt,
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{
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BacktraceIterator *b = &kbt->it;
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if (b->pc == VDSO_BASE && b->sp < PAGE_OFFSET &&
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if (is_sigreturn(b->pc) && b->sp < PAGE_OFFSET &&
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b->sp % sizeof(long) == 0) {
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int retval;
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pagefault_disable();
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@ -23,8 +23,10 @@
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#include <linux/smp.h>
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#include <linux/delay.h>
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#include <linux/module.h>
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#include <linux/timekeeper_internal.h>
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#include <asm/irq_regs.h>
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#include <asm/traps.h>
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#include <asm/vdso.h>
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#include <hv/hypervisor.h>
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#include <arch/interrupts.h>
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#include <arch/spr_def.h>
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@ -110,7 +112,6 @@ void __init time_init(void)
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setup_tile_timer();
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}
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/*
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* Define the tile timer clock event device. The timer is driven by
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* the TILE_TIMER_CONTROL register, which consists of a 31-bit down
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@ -237,3 +238,37 @@ cycles_t ns2cycles(unsigned long nsecs)
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struct clock_event_device *dev = &__raw_get_cpu_var(tile_timer);
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return ((u64)nsecs * dev->mult) >> dev->shift;
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}
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void update_vsyscall_tz(void)
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{
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/* Userspace gettimeofday will spin while this value is odd. */
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++vdso_data->tz_update_count;
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smp_wmb();
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vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
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vdso_data->tz_dsttime = sys_tz.tz_dsttime;
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smp_wmb();
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++vdso_data->tz_update_count;
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}
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void update_vsyscall(struct timekeeper *tk)
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{
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struct timespec wall_time = tk_xtime(tk);
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struct timespec *wtm = &tk->wall_to_monotonic;
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struct clocksource *clock = tk->clock;
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if (clock != &cycle_counter_cs)
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return;
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/* Userspace gettimeofday will spin while this value is odd. */
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++vdso_data->tb_update_count;
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smp_wmb();
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vdso_data->xtime_tod_stamp = clock->cycle_last;
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vdso_data->xtime_clock_sec = wall_time.tv_sec;
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vdso_data->xtime_clock_nsec = wall_time.tv_nsec;
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vdso_data->wtom_clock_sec = wtm->tv_sec;
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vdso_data->wtom_clock_nsec = wtm->tv_nsec;
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vdso_data->mult = clock->mult;
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vdso_data->shift = clock->shift;
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smp_wmb();
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++vdso_data->tb_update_count;
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}
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@ -0,0 +1,212 @@
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/*
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* Copyright 2012 Tilera Corporation. All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation, version 2.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
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* NON INFRINGEMENT. See the GNU General Public License for
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* more details.
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*/
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#include <linux/binfmts.h>
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#include <linux/compat.h>
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#include <linux/elf.h>
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#include <linux/mm.h>
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#include <linux/pagemap.h>
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#include <asm/vdso.h>
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#include <asm/mman.h>
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#include <asm/sections.h>
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#include <arch/sim.h>
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/* The alignment of the vDSO. */
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#define VDSO_ALIGNMENT PAGE_SIZE
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static unsigned int vdso_pages;
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static struct page **vdso_pagelist;
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#ifdef CONFIG_COMPAT
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static unsigned int vdso32_pages;
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static struct page **vdso32_pagelist;
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#endif
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static int vdso_ready;
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/*
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* The vdso data page.
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*/
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static union {
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struct vdso_data data;
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u8 page[PAGE_SIZE];
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} vdso_data_store __page_aligned_data;
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struct vdso_data *vdso_data = &vdso_data_store.data;
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static unsigned int __read_mostly vdso_enabled = 1;
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static struct page **vdso_setup(void *vdso_kbase, unsigned int pages)
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{
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int i;
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struct page **pagelist;
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pagelist = kzalloc(sizeof(struct page *) * (pages + 1), GFP_KERNEL);
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BUG_ON(pagelist == NULL);
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for (i = 0; i < pages - 1; i++) {
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struct page *pg = virt_to_page(vdso_kbase + i*PAGE_SIZE);
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ClearPageReserved(pg);
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pagelist[i] = pg;
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}
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pagelist[pages - 1] = virt_to_page(vdso_data);
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pagelist[pages] = NULL;
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return pagelist;
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}
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static int __init vdso_init(void)
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{
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int data_pages = sizeof(vdso_data_store) >> PAGE_SHIFT;
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/*
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* We can disable vDSO support generally, but we need to retain
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* one page to support the two-bundle (16-byte) rt_sigreturn path.
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*/
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if (!vdso_enabled) {
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size_t offset = (unsigned long)&__vdso_rt_sigreturn;
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static struct page *sigret_page;
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sigret_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
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BUG_ON(sigret_page == NULL);
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vdso_pagelist = &sigret_page;
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vdso_pages = 1;
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BUG_ON(offset >= PAGE_SIZE);
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memcpy(page_address(sigret_page) + offset,
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vdso_start + offset, 16);
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#ifdef CONFIG_COMPAT
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vdso32_pages = vdso_pages;
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vdso32_pagelist = vdso_pagelist;
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#endif
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vdso_ready = 1;
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return 0;
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}
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vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT;
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vdso_pages += data_pages;
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vdso_pagelist = vdso_setup(vdso_start, vdso_pages);
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#ifdef CONFIG_COMPAT
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vdso32_pages = (vdso32_end - vdso32_start) >> PAGE_SHIFT;
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vdso32_pages += data_pages;
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vdso32_pagelist = vdso_setup(vdso32_start, vdso32_pages);
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#endif
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smp_wmb();
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vdso_ready = 1;
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return 0;
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}
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arch_initcall(vdso_init);
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const char *arch_vma_name(struct vm_area_struct *vma)
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{
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if (vma->vm_mm && vma->vm_start == VDSO_BASE)
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return "[vdso]";
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#ifndef __tilegx__
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if (vma->vm_start == MEM_USER_INTRPT)
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return "[intrpt]";
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#endif
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return NULL;
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}
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struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
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{
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return NULL;
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}
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int in_gate_area(struct mm_struct *mm, unsigned long address)
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{
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return 0;
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}
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int in_gate_area_no_mm(unsigned long address)
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||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
int setup_vdso_pages(void)
|
||||
{
|
||||
struct page **pagelist;
|
||||
unsigned long pages;
|
||||
struct mm_struct *mm = current->mm;
|
||||
unsigned long vdso_base = 0;
|
||||
int retval = 0;
|
||||
|
||||
if (!vdso_ready)
|
||||
return 0;
|
||||
|
||||
mm->context.vdso_base = 0;
|
||||
|
||||
pagelist = vdso_pagelist;
|
||||
pages = vdso_pages;
|
||||
#ifdef CONFIG_COMPAT
|
||||
if (is_compat_task()) {
|
||||
pagelist = vdso32_pagelist;
|
||||
pages = vdso32_pages;
|
||||
}
|
||||
#endif
|
||||
|
||||
/*
|
||||
* vDSO has a problem and was disabled, just don't "enable" it for the
|
||||
* process.
|
||||
*/
|
||||
if (pages == 0)
|
||||
return 0;
|
||||
|
||||
vdso_base = get_unmapped_area(NULL, vdso_base,
|
||||
(pages << PAGE_SHIFT) +
|
||||
((VDSO_ALIGNMENT - 1) & PAGE_MASK),
|
||||
0, 0);
|
||||
if (IS_ERR_VALUE(vdso_base)) {
|
||||
retval = vdso_base;
|
||||
return retval;
|
||||
}
|
||||
|
||||
/* Add required alignment. */
|
||||
vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
|
||||
|
||||
/*
|
||||
* Put vDSO base into mm struct. We need to do this before calling
|
||||
* install_special_mapping or the perf counter mmap tracking code
|
||||
* will fail to recognise it as a vDSO (since arch_vma_name fails).
|
||||
*/
|
||||
mm->context.vdso_base = vdso_base;
|
||||
|
||||
/*
|
||||
* our vma flags don't have VM_WRITE so by default, the process isn't
|
||||
* allowed to write those pages.
|
||||
* gdb can break that with ptrace interface, and thus trigger COW on
|
||||
* those pages but it's then your responsibility to never do that on
|
||||
* the "data" page of the vDSO or you'll stop getting kernel updates
|
||||
* and your nice userland gettimeofday will be totally dead.
|
||||
* It's fine to use that for setting breakpoints in the vDSO code
|
||||
* pages though
|
||||
*/
|
||||
retval = install_special_mapping(mm, vdso_base,
|
||||
pages << PAGE_SHIFT,
|
||||
VM_READ|VM_EXEC |
|
||||
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
|
||||
pagelist);
|
||||
if (retval)
|
||||
mm->context.vdso_base = 0;
|
||||
|
||||
return retval;
|
||||
}
|
||||
|
||||
static __init int vdso_func(char *s)
|
||||
{
|
||||
return kstrtouint(s, 0, &vdso_enabled);
|
||||
}
|
||||
__setup("vdso=", vdso_func);
|
||||
|
|
@ -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,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)
|
||||
|
|
@ -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
|
||||
|
|
@ -0,0 +1,87 @@
|
|||
/*
|
||||
* 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;
|
||||
local:*;
|
||||
};
|
||||
}
|
||||
|
|
@ -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
|
||||
|
|
@ -0,0 +1,107 @@
|
|||
/*
|
||||
* 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/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
|
||||
|
||||
/*
|
||||
* 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;
|
||||
}
|
||||
|
||||
int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
|
||||
{
|
||||
cycles_t cycles;
|
||||
unsigned long count, sec, ns;
|
||||
volatile struct vdso_data *vdso_data;
|
||||
|
||||
vdso_data = (struct vdso_data *)get_datapage();
|
||||
/* The use of the timezone is obsolete, normally tz is NULL. */
|
||||
if (unlikely(tz != NULL)) {
|
||||
while (1) {
|
||||
/* Spin until the update finish. */
|
||||
count = vdso_data->tz_update_count;
|
||||
if (count & 1)
|
||||
continue;
|
||||
|
||||
tz->tz_minuteswest = vdso_data->tz_minuteswest;
|
||||
tz->tz_dsttime = vdso_data->tz_dsttime;
|
||||
|
||||
/* Check whether updated, read again if so. */
|
||||
if (count == vdso_data->tz_update_count)
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
if (unlikely(tv == NULL))
|
||||
return 0;
|
||||
|
||||
while (1) {
|
||||
/* Spin until the update finish. */
|
||||
count = vdso_data->tb_update_count;
|
||||
if (count & 1)
|
||||
continue;
|
||||
|
||||
cycles = (get_cycles() - vdso_data->xtime_tod_stamp);
|
||||
ns = (cycles * vdso_data->mult) >> vdso_data->shift;
|
||||
sec = vdso_data->xtime_clock_sec;
|
||||
ns += vdso_data->xtime_clock_nsec;
|
||||
if (ns >= NSEC_PER_SEC) {
|
||||
ns -= NSEC_PER_SEC;
|
||||
sec += 1;
|
||||
}
|
||||
|
||||
/* Check whether updated, read again if so. */
|
||||
if (count == vdso_data->tb_update_count)
|
||||
break;
|
||||
}
|
||||
|
||||
tv->tv_sec = sec;
|
||||
tv->tv_usec = ns / 1000;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
int gettimeofday(struct timeval *tv, struct timezone *tz)
|
||||
__attribute__((weak, alias("__vdso_gettimeofday")));
|
||||
|
|
@ -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)
|
||||
|
|
@ -21,6 +21,7 @@
|
|||
#include <asm/pgtable.h>
|
||||
#include <asm/pgalloc.h>
|
||||
#include <asm/sections.h>
|
||||
#include <asm/vdso.h>
|
||||
#include <arch/sim.h>
|
||||
|
||||
/* Notify a running simulator, if any, that an exec just occurred. */
|
||||
|
|
@ -102,37 +103,10 @@ static void sim_notify_interp(unsigned long load_addr)
|
|||
}
|
||||
|
||||
|
||||
/* Kernel address of page used to map read-only kernel data into userspace. */
|
||||
static void *vdso_page;
|
||||
|
||||
/* One-entry array used for install_special_mapping. */
|
||||
static struct page *vdso_pages[1];
|
||||
|
||||
static int __init vdso_setup(void)
|
||||
{
|
||||
vdso_page = (void *)get_zeroed_page(GFP_ATOMIC);
|
||||
memcpy(vdso_page, __rt_sigreturn, __rt_sigreturn_end - __rt_sigreturn);
|
||||
vdso_pages[0] = virt_to_page(vdso_page);
|
||||
return 0;
|
||||
}
|
||||
device_initcall(vdso_setup);
|
||||
|
||||
const char *arch_vma_name(struct vm_area_struct *vma)
|
||||
{
|
||||
if (vma->vm_private_data == vdso_pages)
|
||||
return "[vdso]";
|
||||
#ifndef __tilegx__
|
||||
if (vma->vm_start == MEM_USER_INTRPT)
|
||||
return "[intrpt]";
|
||||
#endif
|
||||
return NULL;
|
||||
}
|
||||
|
||||
int arch_setup_additional_pages(struct linux_binprm *bprm,
|
||||
int executable_stack)
|
||||
{
|
||||
struct mm_struct *mm = current->mm;
|
||||
unsigned long vdso_base;
|
||||
int retval = 0;
|
||||
|
||||
down_write(&mm->mmap_sem);
|
||||
|
|
@ -145,14 +119,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
|
|||
if (!notify_exec(mm))
|
||||
sim_notify_exec(bprm->filename);
|
||||
|
||||
/*
|
||||
* MAYWRITE to allow gdb to COW and set breakpoints
|
||||
*/
|
||||
vdso_base = VDSO_BASE;
|
||||
retval = install_special_mapping(mm, vdso_base, PAGE_SIZE,
|
||||
VM_READ|VM_EXEC|
|
||||
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
|
||||
vdso_pages);
|
||||
retval = setup_vdso_pages();
|
||||
|
||||
#ifndef __tilegx__
|
||||
/*
|
||||
|
|
|
|||
Loading…
Reference in New Issue