From c1b0db56604b4ccc55a325104b14093aeedeb829 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 28 Apr 2011 18:43:01 +0100 Subject: ARM: 6889/1: futex: add SMP futex support when !CPU_USE_DOMAINS This patch uses the load/store exclusive instructions to add SMP futex support for ARM. Since the ARM architecture does not provide instructions for unprivileged exclusive memory accesses, we can only provide SMP futexes when CPU domain support is disabled. Cc: Nicolas Pitre Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/include/asm/futex.h | 137 ++++++++++++++++++++++++++++--------------- 1 file changed, 90 insertions(+), 47 deletions(-) (limited to 'arch/arm/include/asm') diff --git a/arch/arm/include/asm/futex.h b/arch/arm/include/asm/futex.h index 199a6b6de7f4..8c73900da9ed 100644 --- a/arch/arm/include/asm/futex.h +++ b/arch/arm/include/asm/futex.h @@ -3,16 +3,74 @@ #ifdef __KERNEL__ +#if defined(CONFIG_CPU_USE_DOMAINS) && defined(CONFIG_SMP) +/* ARM doesn't provide unprivileged exclusive memory accessors */ +#include +#else + +#include +#include +#include + +#define __futex_atomic_ex_table(err_reg) \ + "3:\n" \ + " .pushsection __ex_table,\"a\"\n" \ + " .align 3\n" \ + " .long 1b, 4f, 2b, 4f\n" \ + " .popsection\n" \ + " .pushsection .fixup,\"ax\"\n" \ + "4: mov %0, " err_reg "\n" \ + " b 3b\n" \ + " .popsection" + #ifdef CONFIG_SMP -#include +#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ + smp_mb(); \ + __asm__ __volatile__( \ + "1: ldrex %1, [%2]\n" \ + " " insn "\n" \ + "2: strex %1, %0, [%2]\n" \ + " teq %1, #0\n" \ + " bne 1b\n" \ + " mov %0, #0\n" \ + __futex_atomic_ex_table("%4") \ + : "=&r" (ret), "=&r" (oldval) \ + : "r" (uaddr), "r" (oparg), "Ir" (-EFAULT) \ + : "cc", "memory") + +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + int ret; + u32 val; + + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + + smp_mb(); + __asm__ __volatile__("@futex_atomic_cmpxchg_inatomic\n" + "1: ldrex %1, [%4]\n" + " teq %1, %2\n" + " ite eq @ explicit IT needed for the 2b label\n" + "2: strexeq %0, %3, [%4]\n" + " movne %0, #0\n" + " teq %0, #0\n" + " bne 1b\n" + __futex_atomic_ex_table("%5") + : "=&r" (ret), "=&r" (val) + : "r" (oldval), "r" (newval), "r" (uaddr), "Ir" (-EFAULT) + : "cc", "memory"); + smp_mb(); + + *uval = val; + return ret; +} #else /* !SMP, we can work around lack of atomic ops by disabling preemption */ -#include #include -#include -#include #include #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ @@ -21,19 +79,37 @@ " " insn "\n" \ "2: " T(str) " %0, [%2]\n" \ " mov %0, #0\n" \ - "3:\n" \ - " .pushsection __ex_table,\"a\"\n" \ - " .align 3\n" \ - " .long 1b, 4f, 2b, 4f\n" \ - " .popsection\n" \ - " .pushsection .fixup,\"ax\"\n" \ - "4: mov %0, %4\n" \ - " b 3b\n" \ - " .popsection" \ + __futex_atomic_ex_table("%4") \ : "=&r" (ret), "=&r" (oldval) \ : "r" (uaddr), "r" (oparg), "Ir" (-EFAULT) \ : "cc", "memory") +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + int ret = 0; + u32 val; + + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + + __asm__ __volatile__("@futex_atomic_cmpxchg_inatomic\n" + "1: " T(ldr) " %1, [%4]\n" + " teq %1, %2\n" + " it eq @ explicit IT needed for the 2b label\n" + "2: " T(streq) " %3, [%4]\n" + __futex_atomic_ex_table("%5") + : "+r" (ret), "=&r" (val) + : "r" (oldval), "r" (newval), "r" (uaddr), "Ir" (-EFAULT) + : "cc", "memory"); + + *uval = val; + return ret; +} + +#endif /* !SMP */ + static inline int futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr) { @@ -87,39 +163,6 @@ futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr) return ret; } -static inline int -futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, - u32 oldval, u32 newval) -{ - int ret = 0; - u32 val; - - if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) - return -EFAULT; - - __asm__ __volatile__("@futex_atomic_cmpxchg_inatomic\n" - "1: " T(ldr) " %1, [%4]\n" - " teq %1, %2\n" - " it eq @ explicit IT needed for the 2b label\n" - "2: " T(streq) " %3, [%4]\n" - "3:\n" - " .pushsection __ex_table,\"a\"\n" - " .align 3\n" - " .long 1b, 4f, 2b, 4f\n" - " .popsection\n" - " .pushsection .fixup,\"ax\"\n" - "4: mov %0, %5\n" - " b 3b\n" - " .popsection" - : "+r" (ret), "=&r" (val) - : "r" (oldval), "r" (newval), "r" (uaddr), "Ir" (-EFAULT) - : "cc", "memory"); - - *uval = val; - return ret; -} - -#endif /* !SMP */ - +#endif /* !(CPU_USE_DOMAINS && SMP) */ #endif /* __KERNEL__ */ #endif /* _ASM_ARM_FUTEX_H */ -- cgit v1.2.3 From 5be6f62b0059a3344437b4c2877152c58cb3fdeb Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Mon, 18 Apr 2011 14:48:23 +0100 Subject: ARM: 6883/1: ptrace: Migrate to regsets framework This patch migrates the implementation of the ptrace interface for the core integer registers, legacy FPA registers and VFP registers to use the regsets framework. As an added bonus, all this stuff gets included in coredumps at no extra cost. Without this patch, coredumps contained no VFP state. Third-party extension register sets (iwmmx, crunch) are not migrated by this patch, and continue to use the old implementation; these should be migratable without much extra work. Signed-off-by: Dave Martin Acked-by: Will Deacon Signed-off-by: Russell King --- arch/arm/include/asm/elf.h | 1 + arch/arm/include/asm/ptrace.h | 6 ++++++ 2 files changed, 7 insertions(+) (limited to 'arch/arm/include/asm') diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h index c3cd8755e648..0e9ce8d9686e 100644 --- a/arch/arm/include/asm/elf.h +++ b/arch/arm/include/asm/elf.h @@ -108,6 +108,7 @@ struct task_struct; int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs); #define ELF_CORE_COPY_TASK_REGS dump_task_regs +#define CORE_DUMP_USE_REGSET #define ELF_EXEC_PAGESIZE 4096 /* This is the location that an ET_DYN program is loaded if exec'ed. Typical diff --git a/arch/arm/include/asm/ptrace.h b/arch/arm/include/asm/ptrace.h index a8ff22b2a391..312d10877bd7 100644 --- a/arch/arm/include/asm/ptrace.h +++ b/arch/arm/include/asm/ptrace.h @@ -128,6 +128,12 @@ struct pt_regs { #define ARM_r0 uregs[0] #define ARM_ORIG_r0 uregs[17] +/* + * The size of the user-visible VFP state as seen by PTRACE_GET/SETVFPREGS + * and core dumps. + */ +#define ARM_VFPREGS_SIZE ( 32 * 8 /*fpregs*/ + 4 /*fpscr*/ ) + #ifdef __KERNEL__ #define user_mode(regs) \ -- cgit v1.2.3 From 603605abae9ee731bdafb2af83a487d98a568815 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 23 May 2011 17:16:59 +0100 Subject: ARM: 6939/1: fix missing 'cpu_relax()' declaration ARM build fails with the following symptom: CC arch/arm/kernel/asm-offsets.s In file included from include/linux/seqlock.h:29, from include/linux/time.h:8, from include/linux/timex.h:56, from include/linux/sched.h:57, from arch/arm/kernel/asm-offsets.c:13: include/linux/spinlock.h: In function 'spin_unlock_wait': include/linux/spinlock.h:360: error: implicit declaration of function 'cpu_relax' make[1]: *** [arch/arm/kernel/asm-offsets.s] Error 1 Fix it by including . Signed-off-by: Marc Zyngier Signed-off-by: Russell King --- arch/arm/include/asm/spinlock.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm/include/asm') diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h index fdd3820edff8..65fa3c88095c 100644 --- a/arch/arm/include/asm/spinlock.h +++ b/arch/arm/include/asm/spinlock.h @@ -5,6 +5,8 @@ #error SMP not supported on pre-ARMv6 CPUs #endif +#include + /* * sev and wfe are ARMv6K extensions. Uniprocessor ARMv6 may not have the K * extensions, so when running on UP, we have to patch these instructions away. -- cgit v1.2.3