[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAFTL4hzpwLO--SRUzpJz=zKbupSEYirNcO-KM=ShOMwjoJ0LvA@mail.gmail.com>
Date: Sun, 10 Feb 2013 11:32:49 +0100
From: Frederic Weisbecker <fweisbec@...il.com>
To: Li Zhong <zhong@...ux.vnet.ibm.com>
Cc: linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
paulmck@...ux.vnet.ibm.com, benh@...nel.crashing.org,
paulus@...ba.org
Subject: Re: [RFC PATCH 1/5] powerpc: Syscall hooks for context tracking subsystem
2013/2/1 Li Zhong <zhong@...ux.vnet.ibm.com>:
> This is the syscall slow path hooks for context tracking subsystem,
> corresponding to
> [PATCH] x86: Syscall hooks for userspace RCU extended QS
> commit bf5a3c13b939813d28ce26c01425054c740d6731
>
> TIF_MEMDIE is moved to the second 16-bits (with value 17), as it seems there
> is no asm code using it. TIF_NOHZ is added to _TIF_SYCALL_T_OR_A, so it is
> better for it to be in the same 16 bits with others in the group, so in the
> asm code, andi. with this group could work.
>
> Signed-off-by: Li Zhong <zhong@...ux.vnet.ibm.com>
Looks good. Thanks.
Acked-by: Frederic Weisbecker <fweisbec@...il.com>
> ---
> arch/powerpc/include/asm/thread_info.h | 7 +++++--
> arch/powerpc/kernel/ptrace.c | 5 +++++
> 2 files changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
> index 406b7b9..414a261 100644
> --- a/arch/powerpc/include/asm/thread_info.h
> +++ b/arch/powerpc/include/asm/thread_info.h
> @@ -97,7 +97,7 @@ static inline struct thread_info *current_thread_info(void)
> #define TIF_PERFMON_CTXSW 6 /* perfmon needs ctxsw calls */
> #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
> #define TIF_SINGLESTEP 8 /* singlestepping active */
> -#define TIF_MEMDIE 9 /* is terminating due to OOM killer */
> +#define TIF_NOHZ 9 /* in adaptive nohz mode */
> #define TIF_SECCOMP 10 /* secure computing */
> #define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */
> #define TIF_NOERROR 12 /* Force successful syscall return */
> @@ -106,6 +106,7 @@ static inline struct thread_info *current_thread_info(void)
> #define TIF_SYSCALL_TRACEPOINT 15 /* syscall tracepoint instrumentation */
> #define TIF_EMULATE_STACK_STORE 16 /* Is an instruction emulation
> for stack store? */
> +#define TIF_MEMDIE 17 /* is terminating due to OOM killer */
>
> /* as above, but as bit values */
> #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
> @@ -124,8 +125,10 @@ static inline struct thread_info *current_thread_info(void)
> #define _TIF_UPROBE (1<<TIF_UPROBE)
> #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
> #define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE)
> +#define _TIF_NOHZ (1<<TIF_NOHZ)
> #define _TIF_SYSCALL_T_OR_A (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
> - _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT)
> + _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
> + _TIF_NOHZ)
>
> #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
> _TIF_NOTIFY_RESUME | _TIF_UPROBE)
> diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
> index c497000..62238dd 100644
> --- a/arch/powerpc/kernel/ptrace.c
> +++ b/arch/powerpc/kernel/ptrace.c
> @@ -32,6 +32,7 @@
> #include <trace/syscall.h>
> #include <linux/hw_breakpoint.h>
> #include <linux/perf_event.h>
> +#include <linux/context_tracking.h>
>
> #include <asm/uaccess.h>
> #include <asm/page.h>
> @@ -1745,6 +1746,8 @@ long do_syscall_trace_enter(struct pt_regs *regs)
> {
> long ret = 0;
>
> + user_exit();
> +
> secure_computing_strict(regs->gpr[0]);
>
> if (test_thread_flag(TIF_SYSCALL_TRACE) &&
> @@ -1789,4 +1792,6 @@ void do_syscall_trace_leave(struct pt_regs *regs)
> step = test_thread_flag(TIF_SINGLESTEP);
> if (step || test_thread_flag(TIF_SYSCALL_TRACE))
> tracehook_report_syscall_exit(regs, step);
> +
> + user_enter();
> }
> --
> 1.7.9.5
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists