From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id B6C281A02BF for ; Tue, 9 Feb 2016 21:58:24 +1100 (AEDT) In-Reply-To: <1448290875-20896-2-git-send-email-dougmill@linux.vnet.ibm.com> To: Douglas Miller , linuxppc-dev@lists.ozlabs.org From: Michael Ellerman Subject: Re: powerpc/xmon: Add xmon command to dump process/task similar to ps(1) Message-Id: <20160209105824.9231E140B97@ozlabs.org> Date: Tue, 9 Feb 2016 21:58:24 +1100 (AEDT) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2015-23-11 at 15:01:15 UTC, Douglas Miller wrote: > Add 'P' command with optional task_struct address to dump all/one task's > information: task pointer, kernel stack pointer, PID, PPID, state > (interpreted), CPU where (last) running, and command. > > Introduce XMON_PROTECT macro to standardize memory-access-fault > protection (setjmp). Initially used only by the 'P' command. Hi Doug, Sorry this has taken a while, it keeps getting preempted by more important patches. I'm also not a big fan of the protect macro, it works for this case, but it's already a bit ugly calling for_each_process() inside the macro, and it would be even worse for multi line logic. I think I'd rather just open code it, and hopefully we can come up with a better solution for catching errors in the long run. I also renamed the routines to use "task", because "proc" in xmon is already used to mean "procedure", and the struct is task_struct after all. How does this look? cheers diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index 47e195d66a9a..942796fa4767 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -163,6 +163,7 @@ static int cpu_cmd(void); static void csum(void); static void bootcmds(void); static void proccall(void); +static void show_tasks(void); void dump_segments(void); static void symbol_lookup(void); static void xmon_show_stack(unsigned long sp, unsigned long lr, @@ -238,6 +239,7 @@ Commands:\n\ mz zero a block of memory\n\ mi show information about memory allocation\n\ p call a procedure\n\ + P list processes/tasks\n\ r print registers\n\ s single step\n" #ifdef CONFIG_SPU_BASE @@ -967,6 +969,9 @@ cmds(struct pt_regs *excp) case 'p': proccall(); break; + case 'P': + show_tasks(); + break; #ifdef CONFIG_PPC_STD_MMU case 'u': dump_segments(); @@ -2566,6 +2571,61 @@ memzcan(void) printf("%.8x\n", a - mskip); } +static void show_task(struct task_struct *tsk) +{ + char state; + + /* + * Cloned from kdb_task_state_char(), which is not entirely + * appropriate for calling from xmon. This could be moved + * to a common, generic, routine used by both. + */ + state = (tsk->state == 0) ? 'R' : + (tsk->state < 0) ? 'U' : + (tsk->state & TASK_UNINTERRUPTIBLE) ? 'D' : + (tsk->state & TASK_STOPPED) ? 'T' : + (tsk->state & TASK_TRACED) ? 'C' : + (tsk->exit_state & EXIT_ZOMBIE) ? 'Z' : + (tsk->exit_state & EXIT_DEAD) ? 'E' : + (tsk->state & TASK_INTERRUPTIBLE) ? 'S' : '?'; + + printf("%p %016lx %6d %6d %c %2d %s\n", tsk, + tsk->thread.ksp, + tsk->pid, tsk->parent->pid, + state, task_thread_info(tsk)->cpu, + tsk->comm); +} + +static void show_tasks(void) +{ + unsigned long tskv; + struct task_struct *tsk = NULL; + + printf(" task_struct ->thread.ksp PID PPID S P CMD\n"); + + if (scanhex(&tskv)) + tsk = (struct task_struct *)tskv; + + if (setjmp(bus_error_jmp) != 0) { + catch_memory_errors = 0; + printf("*** Error dumping task %p\n", tsk); + return; + } + + catch_memory_errors = 1; + sync(); + + if (tsk) + show_task(tsk); + else + for_each_process(tsk) + show_task(tsk); + + sync(); + __delay(200); + catch_memory_errors = 0; +} + static void proccall(void) { unsigned long args[8];