From b86040a59feb255a8193173caa4d5199464433d5 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Fri, 24 Jul 2009 12:32:54 +0100 Subject: Thumb-2: Implementation of the unified start-up and exceptions code This patch implements the ARM/Thumb-2 unified kernel start-up and exception handling code. Signed-off-by: Catalin Marinas --- arch/arm/kernel/entry-common.S | 28 ++++++++-------------------- 1 file changed, 8 insertions(+), 20 deletions(-) (limited to 'arch/arm/kernel/entry-common.S') diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 366e5097a41a..a0540c9f1f0c 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -33,14 +33,7 @@ ret_fast_syscall: /* perform architecture specific actions before user return */ arch_ret_to_user r1, lr - @ fast_restore_user_regs - ldr r1, [sp, #S_OFF + S_PSR] @ get calling cpsr - ldr lr, [sp, #S_OFF + S_PC]! @ get pc - msr spsr_cxsf, r1 @ save in spsr_svc - ldmdb sp, {r1 - lr}^ @ get calling r1 - lr - mov r0, r0 - add sp, sp, #S_FRAME_SIZE - S_PC - movs pc, lr @ return & move spsr_svc into cpsr + restore_user_regs fast = 1, offset = S_OFF UNWIND(.fnend ) /* @@ -73,14 +66,7 @@ no_work_pending: /* perform architecture specific actions before user return */ arch_ret_to_user r1, lr - @ slow_restore_user_regs - ldr r1, [sp, #S_PSR] @ get calling cpsr - ldr lr, [sp, #S_PC]! @ get pc - msr spsr_cxsf, r1 @ save in spsr_svc - ldmdb sp, {r0 - lr}^ @ get calling r0 - lr - mov r0, r0 - add sp, sp, #S_FRAME_SIZE - S_PC - movs pc, lr @ return & move spsr_svc into cpsr + restore_user_regs fast = 0, offset = 0 ENDPROC(ret_to_user) /* @@ -182,8 +168,10 @@ ftrace_stub: ENTRY(vector_swi) sub sp, sp, #S_FRAME_SIZE stmia sp, {r0 - r12} @ Calling r0 - r12 - add r8, sp, #S_PC - stmdb r8, {sp, lr}^ @ Calling sp, lr + ARM( add r8, sp, #S_PC ) + ARM( stmdb r8, {sp, lr}^ ) @ Calling sp, lr + THUMB( mov r8, sp ) + THUMB( store_user_sp_lr r8, r10, S_SP ) @ calling sp, lr mrs r8, spsr @ called from non-FIQ mode, so ok. str lr, [sp, #S_PC] @ Save calling PC str r8, [sp, #S_PSR] @ Save CPSR @@ -272,7 +260,7 @@ ENTRY(vector_swi) bne __sys_trace cmp scno, #NR_syscalls @ check upper syscall limit - adr lr, ret_fast_syscall @ return address + adr lr, BSYM(ret_fast_syscall) @ return address ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine add r1, sp, #S_OFF @@ -293,7 +281,7 @@ __sys_trace: mov r0, #0 @ trace entry [IP = 0] bl syscall_trace - adr lr, __sys_trace_return @ return address + adr lr, BSYM(__sys_trace_return) @ return address mov scno, r0 @ syscall number (possibly new) add r1, sp, #S_R0 + S_OFF @ pointer to regs cmp scno, #NR_syscalls @ check upper syscall limit -- cgit v1.2.3 From 181f817eaaca4c1f8a9c265d339d2b96de8b245d Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Thu, 13 Aug 2009 20:38:16 +0200 Subject: [ARM] support tracing when using newer compilers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since gcc 4.4 the name and calling convention for function profiling on ARM changed. With this patch both types are supported. See http://sourceware.org/ml/libc-ports/2008-04/msg00009.html for some details. Lightly-Tested-by: Anand Gadiyar Tested-by: Kevin Hilman Signed-off-by: Uwe Kleine-König --- arch/arm/include/asm/ftrace.h | 1 + arch/arm/kernel/armksyms.c | 1 + arch/arm/kernel/entry-common.S | 19 +++++++++++++++++++ 3 files changed, 21 insertions(+) (limited to 'arch/arm/kernel/entry-common.S') diff --git a/arch/arm/include/asm/ftrace.h b/arch/arm/include/asm/ftrace.h index 39c8bc1a006a..0d4c478e01b6 100644 --- a/arch/arm/include/asm/ftrace.h +++ b/arch/arm/include/asm/ftrace.h @@ -7,6 +7,7 @@ #ifndef __ASSEMBLY__ extern void mcount(void); +extern void __gnu_mcount_nc(void); #endif #endif diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c index 531e1860e546..0e627705f746 100644 --- a/arch/arm/kernel/armksyms.c +++ b/arch/arm/kernel/armksyms.c @@ -186,4 +186,5 @@ EXPORT_SYMBOL(_find_next_bit_be); #ifdef CONFIG_FUNCTION_TRACER EXPORT_SYMBOL(mcount); +EXPORT_SYMBOL(__gnu_mcount_nc); #endif diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 366e5097a41a..99208728d48f 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -132,6 +132,25 @@ ftrace_call: #else +ENTRY(__gnu_mcount_nc) + stmdb sp!, {r0-r3, lr} + ldr r0, =ftrace_trace_function + ldr r2, [r0] + adr r0, ftrace_stub + cmp r0, r2 + bne gnu_trace + ldmia sp!, {r0-r3, ip, lr} + bx ip + +gnu_trace: + ldr r1, [sp, #20] @ lr of instrumented routine + mov r0, lr + sub r0, r0, #MCOUNT_INSN_SIZE + mov lr, pc + mov pc, r2 + ldmia sp!, {r0-r3, ip, lr} + bx ip + ENTRY(mcount) stmdb sp!, {r0-r3, lr} ldr r0, =ftrace_trace_function -- cgit v1.2.3 From 369842658a36bcea28ecb643ba4bdb53919330dd Mon Sep 17 00:00:00 2001 From: Mikael Pettersson Date: Sat, 15 Aug 2009 12:58:11 +0100 Subject: ARM: 5677/1: ARM support for TIF_RESTORE_SIGMASK/pselect6/ppoll/epoll_pwait This patch adds support for TIF_RESTORE_SIGMASK to ARM's signal handling, which allows to hook up the pselect6, ppoll, and epoll_pwait syscalls on ARM. Tested here with eabi userspace and a test program with a deliberate race between a child's exit and the parent's sigprocmask/select sequence. Using sys_pselect6() instead of sigprocmask/select reliably prevents the race. The other arch's support for TIF_RESTORE_SIGMASK has evolved over time: In 2.6.16: - add TIF_RESTORE_SIGMASK which parallels TIF_SIGPENDING - test both when checking for pending signal [changed later] - reimplement sys_sigsuspend() to use current->saved_sigmask, TIF_RESTORE_SIGMASK [changed later], and -ERESTARTNOHAND; ditto for sys_rt_sigsuspend(), but drop private code and use common code via __ARCH_WANT_SYS_RT_SIGSUSPEND; - there are now no "extra" calls to do_signal() so its oldset parameter is always ¤t->blocked so need not be passed, also its return value is changed to void - change handle_signal() to return 0/-errno - change do_signal() to honor TIF_RESTORE_SIGMASK: + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK is set + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK + if no signal was delivered and TIF_RESTORE_SIGMASK is set then clear it and restore the sigmask - hook up sys_pselect6() and sys_ppoll() In 2.6.19: - hook up sys_epoll_pwait() In 2.6.26: - allow archs to override how TIF_RESTORE_SIGMASK is implemented; default set_restore_sigmask() sets both TIF_RESTORE_SIGMASK and TIF_SIGPENDING; archs need now just test TIF_SIGPENDING again when checking for pending signal work; some archs now implement TIF_RESTORE_SIGMASK as a secondary/non-atomic thread flag bit - call set_restore_sigmask() in sys_sigsuspend() instead of setting TIF_RESTORE_SIGMASK In 2.6.29-rc: - kill sys_pselect7() which no arch wanted So for 2.6.31-rc6/ARM this patch does the following: - Add TIF_RESTORE_SIGMASK. Use the generic set_restore_sigmask() which sets both TIF_SIGPENDING and TIF_RESTORE_SIGMASK, so TIF_RESTORE_SIGMASK need not claim one of the scarce low thread flags, and existing TIF_SIGPENDING and _TIF_WORK_MASK tests need not be extended for TIF_RESTORE_SIGMASK. - sys_sigsuspend() is reimplemented to use current->saved_sigmask and set_restore_sigmask(), making it identical to most other archs - The private code for sys_rt_sigsuspend() is removed, instead generic code supplies it via __ARCH_WANT_SYS_RT_SIGSUSPEND. - sys_sigsuspend() and sys_rt_sigsuspend() no longer need a pt_regs parameter, so their assembly code wrappers are removed. - handle_signal() is changed to return 0 on success or -errno. - The oldset parameter to do_signal() is now redundant and removed, and the return value is now also redundant and changed to void. - do_signal() is changed to honor TIF_RESTORE_SIGMASK: + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK is set + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK + if no signal was delivered and TIF_RESTORE_SIGMASK is set then clear it and restore the sigmask - Hook up sys_pselect6, sys_ppoll, and sys_epoll_pwait. Signed-off-by: Mikael Pettersson Signed-off-by: Russell King --- arch/arm/include/asm/thread_info.h | 2 + arch/arm/include/asm/unistd.h | 7 ++-- arch/arm/kernel/calls.S | 10 ++--- arch/arm/kernel/entry-common.S | 10 ----- arch/arm/kernel/signal.c | 86 ++++++++++++++++---------------------- 5 files changed, 48 insertions(+), 67 deletions(-) (limited to 'arch/arm/kernel/entry-common.S') diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index 73394e50cbca..e20d80539b42 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -140,6 +140,7 @@ extern void vfp_sync_state(struct thread_info *thread); #define TIF_USING_IWMMXT 17 #define TIF_MEMDIE 18 #define TIF_FREEZE 19 +#define TIF_RESTORE_SIGMASK 20 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) @@ -147,6 +148,7 @@ extern void vfp_sync_state(struct thread_info *thread); #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) #define _TIF_USING_IWMMXT (1 << TIF_USING_IWMMXT) #define _TIF_FREEZE (1 << TIF_FREEZE) +#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK) /* * Change these and you break ASM code in entry-common.S diff --git a/arch/arm/include/asm/unistd.h b/arch/arm/include/asm/unistd.h index 0e97b8cb77d5..9122c9ee18fb 100644 --- a/arch/arm/include/asm/unistd.h +++ b/arch/arm/include/asm/unistd.h @@ -360,8 +360,8 @@ #define __NR_readlinkat (__NR_SYSCALL_BASE+332) #define __NR_fchmodat (__NR_SYSCALL_BASE+333) #define __NR_faccessat (__NR_SYSCALL_BASE+334) - /* 335 for pselect6 */ - /* 336 for ppoll */ +#define __NR_pselect6 (__NR_SYSCALL_BASE+335) +#define __NR_ppoll (__NR_SYSCALL_BASE+336) #define __NR_unshare (__NR_SYSCALL_BASE+337) #define __NR_set_robust_list (__NR_SYSCALL_BASE+338) #define __NR_get_robust_list (__NR_SYSCALL_BASE+339) @@ -372,7 +372,7 @@ #define __NR_vmsplice (__NR_SYSCALL_BASE+343) #define __NR_move_pages (__NR_SYSCALL_BASE+344) #define __NR_getcpu (__NR_SYSCALL_BASE+345) - /* 346 for epoll_pwait */ +#define __NR_epoll_pwait (__NR_SYSCALL_BASE+346) #define __NR_kexec_load (__NR_SYSCALL_BASE+347) #define __NR_utimensat (__NR_SYSCALL_BASE+348) #define __NR_signalfd (__NR_SYSCALL_BASE+349) @@ -432,6 +432,7 @@ #define __ARCH_WANT_SYS_SIGPENDING #define __ARCH_WANT_SYS_SIGPROCMASK #define __ARCH_WANT_SYS_RT_SIGACTION +#define __ARCH_WANT_SYS_RT_SIGSUSPEND #if !defined(CONFIG_AEABI) || defined(CONFIG_OABI_COMPAT) #define __ARCH_WANT_SYS_TIME diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S index f776e72a4cb8..ecfa98954d1d 100644 --- a/arch/arm/kernel/calls.S +++ b/arch/arm/kernel/calls.S @@ -81,7 +81,7 @@ CALL(sys_ni_syscall) /* was sys_ssetmask */ /* 70 */ CALL(sys_setreuid16) CALL(sys_setregid16) - CALL(sys_sigsuspend_wrapper) + CALL(sys_sigsuspend) CALL(sys_sigpending) CALL(sys_sethostname) /* 75 */ CALL(sys_setrlimit) @@ -188,7 +188,7 @@ CALL(sys_rt_sigpending) CALL(sys_rt_sigtimedwait) CALL(sys_rt_sigqueueinfo) - CALL(sys_rt_sigsuspend_wrapper) + CALL(sys_rt_sigsuspend) /* 180 */ CALL(ABI(sys_pread64, sys_oabi_pread64)) CALL(ABI(sys_pwrite64, sys_oabi_pwrite64)) CALL(sys_chown16) @@ -344,8 +344,8 @@ CALL(sys_readlinkat) CALL(sys_fchmodat) CALL(sys_faccessat) -/* 335 */ CALL(sys_ni_syscall) /* eventually pselect6 */ - CALL(sys_ni_syscall) /* eventually ppoll */ +/* 335 */ CALL(sys_pselect6) + CALL(sys_ppoll) CALL(sys_unshare) CALL(sys_set_robust_list) CALL(sys_get_robust_list) @@ -355,7 +355,7 @@ CALL(sys_vmsplice) CALL(sys_move_pages) /* 345 */ CALL(sys_getcpu) - CALL(sys_ni_syscall) /* eventually epoll_pwait */ + CALL(sys_epoll_pwait) CALL(sys_kexec_load) CALL(sys_utimensat) CALL(sys_signalfd) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 366e5097a41a..bfa7f0af7ede 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -373,16 +373,6 @@ sys_clone_wrapper: b sys_clone ENDPROC(sys_clone_wrapper) -sys_sigsuspend_wrapper: - add r3, sp, #S_OFF - b sys_sigsuspend -ENDPROC(sys_sigsuspend_wrapper) - -sys_rt_sigsuspend_wrapper: - add r2, sp, #S_OFF - b sys_rt_sigsuspend -ENDPROC(sys_rt_sigsuspend_wrapper) - sys_sigreturn_wrapper: add r0, sp, #S_OFF b sys_sigreturn diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 93bb4247b7ed..e27ee1f701d5 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -47,57 +47,22 @@ const unsigned long sigreturn_codes[7] = { MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN, }; -static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall); - /* * atomically swap in the new signal mask, and wait for a signal. */ -asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs) +asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask) { - sigset_t saveset; - mask &= _BLOCKABLE; spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; + current->saved_sigmask = current->blocked; siginitset(¤t->blocked, mask); recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - regs->ARM_r0 = -EINTR; - - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - if (do_signal(&saveset, regs, 0)) - return regs->ARM_r0; - } -} - -asmlinkage int -sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, struct pt_regs *regs) -{ - sigset_t saveset, newset; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&newset, unewset, sizeof(newset))) - return -EFAULT; - sigdelsetmask(&newset, ~_BLOCKABLE); - - spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; - current->blocked = newset; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - regs->ARM_r0 = -EINTR; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - if (do_signal(&saveset, regs, 0)) - return regs->ARM_r0; - } + current->state = TASK_INTERRUPTIBLE; + schedule(); + set_restore_sigmask(); + return -ERESTARTNOHAND; } asmlinkage int @@ -545,7 +510,7 @@ static inline void setup_syscall_restart(struct pt_regs *regs) /* * OK, we're invoking a handler */ -static void +static int handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *oldset, struct pt_regs * regs, int syscall) @@ -596,7 +561,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, if (ret != 0) { force_sigsegv(sig, tsk); - return; + return ret; } /* @@ -610,6 +575,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, recalc_sigpending(); spin_unlock_irq(&tsk->sighand->siglock); + return 0; } /* @@ -621,7 +587,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, * the kernel can handle, and then we build all the user-level signal handling * stack-frames in one go after that. */ -static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall) +static void do_signal(struct pt_regs *regs, int syscall) { struct k_sigaction ka; siginfo_t info; @@ -634,7 +600,7 @@ static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall) * if so. */ if (!user_mode(regs)) - return 0; + return; if (try_to_freeze()) goto no_signal; @@ -643,9 +609,24 @@ static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall) signr = get_signal_to_deliver(&info, &ka, regs, NULL); if (signr > 0) { - handle_signal(signr, &ka, &info, oldset, regs, syscall); + sigset_t *oldset; + + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + oldset = ¤t->saved_sigmask; + else + oldset = ¤t->blocked; + if (handle_signal(signr, &ka, &info, oldset, regs, syscall) == 0) { + /* + * A signal was successfully delivered; the saved + * sigmask will have been stored in the signal frame, + * and will be restored by sigreturn, so we can simply + * clear the TIF_RESTORE_SIGMASK flag. + */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + clear_thread_flag(TIF_RESTORE_SIGMASK); + } single_step_set(current); - return 1; + return; } no_signal: @@ -697,14 +678,21 @@ static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall) regs->ARM_r0 == -ERESTARTNOINTR) { setup_syscall_restart(regs); } + + /* If there's no signal to deliver, we just put the saved sigmask + * back. + */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) { + clear_thread_flag(TIF_RESTORE_SIGMASK); + sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); + } } single_step_set(current); - return 0; } asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) { if (thread_flags & _TIF_SIGPENDING) - do_signal(¤t->blocked, regs, syscall); + do_signal(regs, syscall); } -- cgit v1.2.3