- 28 1月, 2012 1 次提交
-
-
由 Dan Carpenter 提交于
Smatch complains that we have some inconsistent NULL checking. If "task" were NULL then it would lead to a NULL dereference later. We can remove this test because earlier on in the function we have: if (!task) task = current; Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com> Acked-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Clemens Ladisch <clemens@ladisch.de> Link: http://lkml.kernel.org/r/20120128105246.GA25092@elgon.mountainSigned-off-by: NIngo Molnar <mingo@elte.hu>
-
- 27 1月, 2012 1 次提交
-
-
由 Prarit Bhargava 提交于
rsyslog will display KERN_EMERG messages on a connected terminal. However, these messages are useless/undecipherable for a general user. For example, after a softlockup we get: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Stack: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Call Trace: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Code: ff ff a8 08 75 25 31 d2 48 8d 86 38 e0 ff ff 48 89 d1 0f 01 c8 0f ae f0 48 8b 86 38 e0 ff ff a8 08 75 08 b1 01 4c 89 e0 0f 01 c9 <e8> ea 69 dd ff 4c 29 e8 48 89 c7 e8 0f bc da ff 49 89 c4 49 89 This happens because the printk levels for these messages are incorrect. Only an informational message should be displayed on a terminal. I modified the printk levels for various messages in the kernel and tested the output by using the drivers/misc/lkdtm.c kernel modules (ie, softlockups, panics, hard lockups, etc.) and confirmed that the console output was still the same and that the output to the terminals was correct. For example, in the case of a softlockup we now see the much more informative: Message from syslogd@intel-s3e37-04 at Jan 25 10:18:06 ... BUG: soft lockup - CPU4 stuck for 60s! instead of the above confusing messages. AFAICT, the messages no longer have to be KERN_EMERG. In the most important case of a panic we set console_verbose(). As for the other less severe cases the correct data is output to the console and /var/log/messages. Successfully tested by me using the drivers/misc/lkdtm.c module. Signed-off-by: NPrarit Bhargava <prarit@redhat.com> Cc: dzickus@redhat.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1327586134-11926-1-git-send-email-prarit@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
-
- 20 12月, 2011 1 次提交
-
-
由 Clemens Ladisch 提交于
When printing the code bytes in show_registers(), the markers around the byte at the fault address could make the printk() format string look like a valid log level and facility code. This would prevent this byte from being printed and result in a spurious newline: [ 7555.765589] Code: 8b 32 e9 94 00 00 00 81 7d 00 ff 00 00 00 0f 87 96 00 00 00 48 8b 83 c0 00 00 00 44 89 e2 44 89 e6 48 89 df 48 8b 80 d8 02 00 00 [ 7555.765683] 8b 48 28 48 89 d0 81 e2 ff 0f 00 00 48 c1 e8 0c 48 c1 e0 04 Add KERN_CONT where needed, and elsewhere in show_registers() for consistency. Signed-off-by: NClemens Ladisch <clemens@ladisch.de> Link: http://lkml.kernel.org/r/4EEFA7AE.9020407@ladisch.deSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
-
- 03 7月, 2011 2 次提交
-
-
由 Frederic Weisbecker 提交于
rbp is used in SAVE_ARGS_IRQ to save the old stack pointer in order to restore it later in ret_from_intr. It is convenient because we save its value in the irq regs and it's easily restored using the leave instruction. However this is a kind of abuse of the frame pointer which role is to help unwinding the kernel by chaining frames together, each node following the return address to the previous frame. But although we are breaking the frame by changing the stack pointer, there is no preceding return address before the new frame. Hence using the frame pointer to link the two stacks breaks the stack unwinders that find a random value instead of a return address here. There is no workaround that can work in every case. We are using the fixup_bp_irq_link() function to dereference that abused frame pointer in the case of non nesting interrupt (which means stack changed). But that doesn't fix the case of interrupts that don't change the stack (but we still have the unconditional frame link), which is the case of hardirq interrupting softirq. We have no way to detect this transition so the frame irq link is considered as a real frame pointer and the return address is dereferenced but it is still a spurious one. There are two possible results of this: either the spurious return address, a random stack value, luckily belongs to the kernel text and then the unwinding can continue and we just have a weird entry in the stack trace. Or it doesn't belong to the kernel text and unwinding stops there. This is the reason why stacktraces (including perf callchains) on irqs that interrupted softirqs don't work very well. To solve this, we don't save the old stack pointer on rbp anymore but we save it to a scratch register that we push on the new stack and that we pop back later on irq return. This preserves the whole frame chain without spurious return addresses in the middle and drops the need for the horrid fixup_bp_irq_link() workaround. And finally irqs that interrupt softirq are sanely unwinded. Before: 99.81% perf [kernel.kallsyms] [k] perf_pending_event | --- perf_pending_event irq_work_run smp_irq_work_interrupt irq_work_interrupt | |--41.60%-- __read | | | |--99.90%-- create_worker | | bench_sched_messaging | | cmd_bench | | run_builtin | | main | | __libc_start_main | --0.10%-- [...] After: 1.64% swapper [kernel.kallsyms] [k] perf_pending_event | --- perf_pending_event irq_work_run smp_irq_work_interrupt irq_work_interrupt | |--95.00%-- arch_irq_work_raise | irq_work_queue | __perf_event_overflow | perf_swevent_overflow | perf_swevent_event | perf_tp_event | perf_trace_softirq | __do_softirq | call_softirq | do_softirq | irq_exit | | | |--73.68%-- smp_apic_timer_interrupt | | apic_timer_interrupt | | | | | |--96.43%-- amd_e400_idle | | | cpu_idle | | | start_secondary Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jan Beulich <JBeulich@novell.com>
-
由 Frederic Weisbecker 提交于
When regs are passed to dump_stack(), we fetch the frame pointer from the regs but the stack pointer is taken from the current frame. Thus the frame and stack pointers may not come from the same context. For example this can result in the unwinder to think the context is in irq, due to the current value of the stack, but the frame pointer coming from the regs points to a frame from another place. It then tries to fix up the irq link but ends up dereferencing a random frame pointer that doesn't belong to the irq stack: [ 9131.706906] ------------[ cut here ]------------ [ 9131.707003] WARNING: at arch/x86/kernel/dumpstack_64.c:129 dump_trace+0x2aa/0x330() [ 9131.707003] Hardware name: AMD690VM-FMH [ 9131.707003] Perf: bad frame pointer = 0000000000000005 in callchain [ 9131.707003] Modules linked in: [ 9131.707003] Pid: 1050, comm: perf Not tainted 3.0.0-rc3+ #181 [ 9131.707003] Call Trace: [ 9131.707003] <IRQ> [<ffffffff8104bd4a>] warn_slowpath_common+0x7a/0xb0 [ 9131.707003] [<ffffffff8104be21>] warn_slowpath_fmt+0x41/0x50 [ 9131.707003] [<ffffffff8178b873>] ? bad_to_user+0x6d/0x10be [ 9131.707003] [<ffffffff8100c2da>] dump_trace+0x2aa/0x330 [ 9131.707003] [<ffffffff810107d3>] ? native_sched_clock+0x13/0x50 [ 9131.707003] [<ffffffff8101b164>] perf_callchain_kernel+0x54/0x70 [ 9131.707003] [<ffffffff810d391f>] perf_prepare_sample+0x19f/0x2a0 [ 9131.707003] [<ffffffff810d546c>] __perf_event_overflow+0x16c/0x290 [ 9131.707003] [<ffffffff810d5430>] ? __perf_event_overflow+0x130/0x290 [ 9131.707003] [<ffffffff810107d3>] ? native_sched_clock+0x13/0x50 [ 9131.707003] [<ffffffff8100fbb9>] ? sched_clock+0x9/0x10 [ 9131.707003] [<ffffffff810752e5>] ? T.375+0x15/0x90 [ 9131.707003] [<ffffffff81084da4>] ? trace_hardirqs_on_caller+0x64/0x180 [ 9131.707003] [<ffffffff810817bd>] ? trace_hardirqs_off+0xd/0x10 [ 9131.707003] [<ffffffff810d5764>] perf_event_overflow+0x14/0x20 [ 9131.707003] [<ffffffff810d588c>] perf_swevent_hrtimer+0x11c/0x130 [ 9131.707003] [<ffffffff817821a1>] ? error_exit+0x51/0xb0 [ 9131.707003] [<ffffffff81072e93>] __run_hrtimer+0x83/0x1e0 [ 9131.707003] [<ffffffff810d5770>] ? perf_event_overflow+0x20/0x20 [ 9131.707003] [<ffffffff81073256>] hrtimer_interrupt+0x106/0x250 [ 9131.707003] [<ffffffff812a3bfd>] ? trace_hardirqs_off_thunk+0x3a/0x3c [ 9131.707003] [<ffffffff81024833>] smp_apic_timer_interrupt+0x53/0x90 [ 9131.707003] [<ffffffff81789053>] apic_timer_interrupt+0x13/0x20 [ 9131.707003] <EOI> [<ffffffff817821a1>] ? error_exit+0x51/0xb0 [ 9131.707003] [<ffffffff8178219c>] ? error_exit+0x4c/0xb0 [ 9131.707003] ---[ end trace b2560d4876709347 ]--- Fix this by simply taking the stack pointer from regs->sp when regs are provided. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
-
- 18 3月, 2011 1 次提交
-
-
由 Namhyung Kim 提交于
Current stack dump code scans entire stack and check each entry contains a pointer to kernel code. If CONFIG_FRAME_POINTER=y it could mark whether the pointer is valid or not based on value of the frame pointer. Invalid entries could be preceded by '?' sign. However this was not going to happen because scan start point was always higher than the frame pointer so that they could not meet. Commit 9c0729dc ("x86: Eliminate bp argument from the stack tracing routines") delayed bp acquisition point, so the bp was read in lower frame, thus all of the entries were marked invalid. This patch fixes this by reverting above commit while retaining stack_frame() helper as suggested by Frederic Weisbecker. End result looks like below: before: [ 3.508329] Call Trace: [ 3.508551] [<ffffffff814f35c9>] ? panic+0x91/0x199 [ 3.508662] [<ffffffff814f3739>] ? printk+0x68/0x6a [ 3.508770] [<ffffffff81a981b2>] ? mount_block_root+0x257/0x26e [ 3.508876] [<ffffffff81a9821f>] ? mount_root+0x56/0x5a [ 3.508975] [<ffffffff81a98393>] ? prepare_namespace+0x170/0x1a9 [ 3.509216] [<ffffffff81a9772b>] ? kernel_init+0x1d2/0x1e2 [ 3.509335] [<ffffffff81003894>] ? kernel_thread_helper+0x4/0x10 [ 3.509442] [<ffffffff814f6880>] ? restore_args+0x0/0x30 [ 3.509542] [<ffffffff81a97559>] ? kernel_init+0x0/0x1e2 [ 3.509641] [<ffffffff81003890>] ? kernel_thread_helper+0x0/0x10 after: [ 3.522991] Call Trace: [ 3.523351] [<ffffffff814f35b9>] panic+0x91/0x199 [ 3.523468] [<ffffffff814f3729>] ? printk+0x68/0x6a [ 3.523576] [<ffffffff81a981b2>] mount_block_root+0x257/0x26e [ 3.523681] [<ffffffff81a9821f>] mount_root+0x56/0x5a [ 3.523780] [<ffffffff81a98393>] prepare_namespace+0x170/0x1a9 [ 3.523885] [<ffffffff81a9772b>] kernel_init+0x1d2/0x1e2 [ 3.523987] [<ffffffff81003894>] kernel_thread_helper+0x4/0x10 [ 3.524228] [<ffffffff814f6880>] ? restore_args+0x0/0x30 [ 3.524345] [<ffffffff81a97559>] ? kernel_init+0x0/0x1e2 [ 3.524445] [<ffffffff81003890>] ? kernel_thread_helper+0x0/0x10 -v5: * fix build breakage with oprofile -v4: * use 0 instead of regs->bp * separate out printk changes -v3: * apply comment from Frederic * add a couple of printk fixes Signed-off-by: NNamhyung Kim <namhyung@gmail.com> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Soren Sandmann <ssp@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Robert Richter <robert.richter@amd.com> LKML-Reference: <1300416006-3163-1-git-send-email-namhyung@gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 25 1月, 2011 1 次提交
-
-
由 Jesper Juhl 提交于
In arch/x86/kernel/dumpstack_64.c::dump_trace() we have this code: ... if (!stack) { unsigned long dummy; stack = &dummy; if (task && task != current) stack = (unsigned long *)task->thread.sp; } bp = stack_frame(task, regs); /* * Print function call entries in all stacks, starting at the * current stack address. If the stacks consist of nested * exceptions */ tinfo = task_thread_info(task); for (;;) { char *id; unsigned long *estack_end; estack_end = in_exception_stack(cpu, (unsigned long)stack, &used, &id); ... You'll notice that we assign to 'stack' the address of the variable 'dummy' which is only in-scope inside the 'if (!stack)'. So when we later access stack (at the end of the above, and assuming we did not take the 'if (task && task != current)' branch) we'll be using the address of a variable that is no longer in scope. I believe this patch is the proper fix, but I freely admit that I'm not 100% certain. Signed-off-by: NJesper Juhl <jj@chaosbits.net> LKML-Reference: <alpine.LNX.2.00.1101242232590.10252@swampdragon.chaosbits.net> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
-
- 18 11月, 2010 1 次提交
-
-
由 Soeren Sandmann Pedersen 提交于
The various stack tracing routines take a 'bp' argument in which the caller is supposed to provide the base pointer to use, or 0 if doesn't have one. Since bp is garbage whenever CONFIG_FRAME_POINTER is not defined, this means all callers in principle should either always pass 0, or be conditional on CONFIG_FRAME_POINTER. However, there are only really three use cases for stack tracing: (a) Trace the current task, including IRQ stack if any (b) Trace the current task, but skip IRQ stack (c) Trace some other task In all cases, if CONFIG_FRAME_POINTER is not defined, bp should just be 0. If it _is_ defined, then - in case (a) bp should be gotten directly from the CPU's register, so the caller should pass NULL for regs, - in case (b) the caller should should pass the IRQ registers to dump_trace(), - in case (c) bp should be gotten from the top of the task's stack, so the caller should pass NULL for regs. Hence, the bp argument is not necessary because the combination of task and regs is sufficient to determine an appropriate value for bp. This patch introduces a new inline function stack_frame(task, regs) that computes the desired bp. This function is then called from the two versions of dump_stack(). Signed-off-by: NSoren Sandmann <ssp@redhat.com> Acked-by: NSteven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arjan van de Ven <arjan@infradead.org>, Cc: Frederic Weisbecker <fweisbec@gmail.com>, Cc: Arnaldo Carvalho de Melo <acme@redhat.com>, LKML-Reference: <m3oc9rop28.fsf@dhcp-100-3-82.bos.redhat.com>> Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
-
- 24 10月, 2010 1 次提交
-
-
由 Jiri Slaby 提交于
The stack output currently looks like this: 7fffffffffffffff 0000000a00000000 ffffffff81093341 0000000000000046 <0> ffff88003a545fd8 0000000000000000 0000000000000000 00007fffa39769c0 <0> ffff88003e403f58 ffffffff8102fc4c ffff88003e403f58 ffff88003e403f78 The superfluous <0> are caused by recent printk KERN_CONT change. <*> is now ignored in printk unless some text follows the level and even then it still has to be the first in the format message. Note that the log_lvl parameter is now completely ignored in show_stack_log_lvl and the stack is dumped with the default level (like for quite some time already). It behaves the same as the rest of the dump, function traces are dumped in the very same manner. Only Code and maybe some lines are printed with EMERG level. Unfortunately I see no way how to fix this conceptually to have the whole oops/BUG/panic output with the same level, so this removed only the superfluous characters for the time being. Just for illustration: <4>Process kworker/0:0 (pid: 0, threadinfo ffff88003c8a6000, task ffff88003c85c100) <0>Stack: <4> ffffffff818022c0 0000000a00000001 0000000000000001 0000000000000046 <4> ffff88003c8a7fd8 0000000000000001 ffff88003c8a7e58 0000000000000000 <4> ffff88003e503f48 ffffffff8102fc4c ffff88003e503f48 ffff88003e503f68 <0>Call Trace: <0> <IRQ> <4> [<ffffffff8102fc4c>] ? call_softirq+0x1c/0x30 ... <0>Code: 00 01 00 00 65 8b 04 25 80 c5 00 00 c7 45 ... Signed-off-by: NJiri Slaby <jslaby@suse.cz> Cc: jirislaby@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <1287586131-16222-1-git-send-email-jslaby@suse.cz> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 09 6月, 2010 1 次提交
-
-
由 Frederic Weisbecker 提交于
arch/x86/include/asm/stacktrace.h and arch/x86/kernel/dumpstack.h declare headers of objects that deal with the same topic. Actually most of the files that include stacktrace.h also include dumpstack.h Although dumpstack.h seems more reserved for internals of stack traces, those are quite often needed to define specialized stack trace operations. And perf event arch headers are going to need access to such low level operations anyway. So don't continue to bother with dumpstack.h as it's not anymore about isolated deep internals. v2: fix struct stack_frame definition conflict in sysprof Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Soeren Sandmann <sandmann@daimi.au.dk>
-
- 10 3月, 2010 1 次提交
-
-
由 Frederic Weisbecker 提交于
We were using the frame pointer based stack walker on every contexts in x86-32, but not in x86-64 where we only use the seven-league boots on the exception stacks. Use it also on irq and process stacks. This utterly accelerate the captures. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
-
- 03 3月, 2010 1 次提交
-
-
由 Frederic Weisbecker 提交于
Callers of a stacktrace might pass bad frame pointers. Those are usually checked for safety in stack walking helpers before any dereferencing, but this is not the case when we need to go through one more frame pointer that backlinks the irq stack to the previous one, as we don't have any reliable address boudaries to compare this frame pointer against. This raises crashes when we record callchains for ftrace events with perf because we don't use the right helpers to capture registers there. We get wrong frame pointers as we call task_pt_regs() even on kernel threads, which is a wrong thing as it gives us the initial state of any kernel threads freshly created. This is even not what we want for user tasks. What we want is a hot snapshot of registers when the ftrace event triggers, not the state before a task entered the kernel. This requires more thoughts to do it correctly though. So first put a guardian to ensure the given frame pointer can be dereferenced to avoid crashes. We'll think about how to fix the callers in a subsequent patch. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: 2.6.33.x <stable@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
-
- 04 2月, 2010 1 次提交
-
-
由 Alexey Dobriyan 提交于
Print modules list during kernel BUG. Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <new-submission> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 13 1月, 2010 1 次提交
-
-
由 Frederic Weisbecker 提交于
The check that ignores the debug and nmi stack frames is useless now that we have a frame pointer that makes us start at the right place. We don't anymore have to deal with these. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1262235183-5320-2-git-send-regression-fweisbec@gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 17 12月, 2009 1 次提交
-
-
由 Frederic Weisbecker 提交于
The current print_context_stack helper that does the stack walking job is good for usual stacktraces as it walks through all the stack and reports even addresses that look unreliable, which is nice when we don't have frame pointers for example. But we have users like perf that only require reliable stacktraces, and those may want a more adapted stack walker, so lets make this function a callback in stacktrace_ops that users can tune for their needs. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1261024834-5336-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 06 12月, 2009 1 次提交
-
-
由 Frederic Weisbecker 提交于
When we enter in irq, two things can happen to preserve the link to the previous frame pointer: - If we were in an irq already, we don't switch to the irq stack as we are inside. We just need to save the previous frame pointer and to link the new one to the previous. - Otherwise we need another level of indirection. We enter the irq with the previous stack. We save the previous bp inside and make bp pointing to its saved address. Then we switch to the irq stack and push bp another time but to the new stack. This makes two levels to dereference instead of one. In the second case, the current stacktrace code omits the second level and loses the frame pointer accuracy. The stack that follows will then be considered as unreliable. Handling that makes the perf callchain happier. Before: 43.94% [k] _raw_read_lock | --- _read_lock | |--60.53%-- send_sigio | __kill_fasync | kill_fasync | evdev_pass_event | evdev_event | input_pass_event | input_handle_event | input_event | synaptics_process_byte | psmouse_handle_byte | psmouse_interrupt | serio_interrupt | i8042_interrupt | handle_IRQ_event | handle_edge_irq | handle_irq | __irqentry_text_start | ret_from_intr | | | |--30.43%-- __select | | | |--17.39%-- 0x454f15 | | | |--13.04%-- __read | | | |--13.04%-- vread_hpet | | | |--13.04%-- _xcb_lock_io | | | --13.04%-- 0x7f630878ce8 After: 50.00% [k] _raw_read_lock | --- _read_lock | |--98.97%-- send_sigio | __kill_fasync | kill_fasync | evdev_pass_event | evdev_event | input_pass_event | input_handle_event | input_event | | | |--96.88%-- synaptics_process_byte | | psmouse_handle_byte | | psmouse_interrupt | | serio_interrupt | | i8042_interrupt | | handle_IRQ_event | | handle_edge_irq | | handle_irq | | __irqentry_text_start | | ret_from_intr | | | | | |--39.78%-- __const_udelay | | | | | | | |--91.89%-- ath5k_hw_register_timeout | | | | ath5k_hw_noise_floor_calibration | | | | ath5k_hw_reset | | | | ath5k_reset | | | | ath5k_config | | | | ieee80211_hw_config | | | | | | | | | |--88.24%-- ieee80211_scan_work | | | | | worker_thread | | | | | kthread | | | | | child_rip | | | | | | | | | --11.76%-- ieee80211_scan_completed | | | | ieee80211_scan_work | | | | worker_thread | | | | kthread | | | | child_rip | | | | | | | --8.11%-- ath5k_hw_noise_floor_calibration | | | ath5k_hw_reset | | | ath5k_reset | | | ath5k_config Note: This does not only affect perf events but also x86-64 stacktraces. They were considered as unreliable once we quit the irq stack frame. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "K. Prasad" <prasad@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com>
-
- 26 11月, 2009 2 次提交
-
-
由 Ingo Molnar 提交于
This warning: [ 847.140022] rb_producer D 0000000000000000 5928 519 2 0x00000000 [ 847.203627] BUG: using smp_processor_id() in preemptible [00000000] code: khungtaskd/517 [ 847.207360] caller is show_stack_log_lvl+0x2e/0x241 [ 847.210364] Pid: 517, comm: khungtaskd Not tainted 2.6.32-rc8-tip+ #13761 [ 847.213395] Call Trace: [ 847.215847] [<ffffffff81413bde>] debug_smp_processor_id+0x1f0/0x20a [ 847.216809] [<ffffffff81015eae>] show_stack_log_lvl+0x2e/0x241 [ 847.220027] [<ffffffff81018512>] show_stack+0x1c/0x1e [ 847.223365] [<ffffffff8107b7db>] sched_show_task+0xe4/0xe9 [ 847.226694] [<ffffffff8112f21f>] check_hung_task+0x140/0x199 [ 847.230261] [<ffffffff8112f4a8>] check_hung_uninterruptible_tasks+0x1b7/0x20f [ 847.233371] [<ffffffff8112f500>] ? watchdog+0x0/0x50 [ 847.236683] [<ffffffff8112f54e>] watchdog+0x4e/0x50 [ 847.240034] [<ffffffff810cee56>] kthread+0x97/0x9f [ 847.243372] [<ffffffff81012aea>] child_rip+0xa/0x20 [ 847.246690] [<ffffffff81e43494>] ? restore_args+0x0/0x30 [ 847.250019] [<ffffffff81e43083>] ? _spin_lock+0xe/0x10 [ 847.253351] [<ffffffff810cedbf>] ? kthread+0x0/0x9f [ 847.256833] [<ffffffff81012ae0>] ? child_rip+0x0/0x20 Happens because on preempt-RCU, khungd calls show_stack() with preemption enabled. Make sure we are not preemptible while walking the IRQ and exception stacks on 64-bit. (32-bit stack dumping is preemption safe.) Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Ingo Molnar 提交于
Make the initialization more readable, plus tidy up a few small visual details as well. No change in functionality. LKML-Reference: <new-submission> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 24 9月, 2009 1 次提交
-
-
由 Alexey Dobriyan 提交于
* remove asm/atomic.h inclusion from linux/utsname.h -- not needed after kref conversion * remove linux/utsname.h inclusion from files which do not need it NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however due to some personality stuff it _is_ needed -- cowardly leave ELF-related headers and files alone. Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 02 7月, 2009 1 次提交
-
-
由 Frederic Weisbecker 提交于
About every callchains recorded with perf record are filled up including the internal perfcounter nmi frame: perf_callchain perf_counter_overflow intel_pmu_handle_irq perf_counter_nmi_handler notifier_call_chain atomic_notifier_call_chain notify_die do_nmi nmi We want ignore this frame as it's not interesting for instrumentation. To solve this, we simply ignore every frames from nmi context. New example of "perf report -s sym -c" after this patch: 9.59% [k] search_by_key 4.88% search_by_key reiserfs_read_locked_inode reiserfs_iget reiserfs_lookup do_lookup __link_path_walk path_walk do_path_lookup user_path_at vfs_fstatat vfs_lstat sys_newlstat system_call_fastpath __lxstat 0x406fb1 3.19% search_by_key search_by_entry_key reiserfs_find_entry reiserfs_lookup do_lookup __link_path_walk path_walk do_path_lookup user_path_at vfs_fstatat vfs_lstat sys_newlstat system_call_fastpath __lxstat 0x406fb1 [...] For now this patch only solves the problem in x86-64. Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Anton Blanchard <anton@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <1246474930-6088-1-git-send-email-fweisbec@gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 18 1月, 2009 2 次提交
-
-
由 Brian Gerst 提交于
Signed-off-by: NBrian Gerst <brgerst@gmail.com> Signed-off-by: NTejun Heo <tj@kernel.org>
-
由 Brian Gerst 提交于
Move the irqstackptr variable from the PDA to per-cpu. Make the stacks themselves per-cpu, removing some specific allocation code. Add a seperate flag (is_boot_cpu) to simplify the per-cpu boot adjustments. tj: * sprinkle some underbars around. * irq_stack_ptr is not used till traps_init(), no reason to initialize it early. On SMP, just leaving it NULL till proper initialization in setup_per_cpu_areas() works. Dropped is_boot_cpu and early irq_stack_ptr initialization. * do DECLARE/DEFINE_PER_CPU(char[IRQ_STACK_SIZE], irq_stack) instead of (char, irq_stack[IRQ_STACK_SIZE]). Signed-off-by: NBrian Gerst <brgerst@gmail.com> Signed-off-by: NTejun Heo <tj@kernel.org>
-
- 03 12月, 2008 1 次提交
-
-
由 Steven Rostedt 提交于
Impact: better dumpstack output I noticed in my crash dumps and even in the stack tracer that a lot of functions listed in the stack trace are simply return_to_handler which is ftrace graphs way to insert its own call into the return of a function. But we lose out where the actually function was called from. This patch adds in hooks to the dumpstack mechanism that detects this and finds the real function to print. Both are printed to let the user know that a hook is still in place. This does give a funny side effect in the stack tracer output: Depth Size Location (80 entries) ----- ---- -------- 0) 4144 48 save_stack_trace+0x2f/0x4d 1) 4096 128 ftrace_call+0x5/0x2b 2) 3968 16 mempool_alloc_slab+0x16/0x18 3) 3952 384 return_to_handler+0x0/0x73 4) 3568 -240 stack_trace_call+0x11d/0x209 5) 3808 144 return_to_handler+0x0/0x73 6) 3664 -128 mempool_alloc+0x4d/0xfe 7) 3792 128 return_to_handler+0x0/0x73 8) 3664 -32 scsi_sg_alloc+0x48/0x4a [scsi_mod] As you can see, the real functions are now negative. This is due to them not being found inside the stack. Signed-off-by: NSteven Rostedt <srostedt@redhat.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 28 10月, 2008 1 次提交
-
-
由 Neil Horman 提交于
Impact: cleanup As promised, now that dumpstack_32 and dumpstack_64 have so many bits in common, we should merge the in-sync bits into a common file, to prevent them from diverging again. This patch removes bits which are common between dumpstack_32.c and dumpstack_64.c and places them in a common dumpstack.c which is built for both 32 and 64 bit arches. Signed-off-by: NNeil Horman <nhorman@tuxdriver.com> Acked-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu> Makefile | 2 arch/x86/kernel/Makefile | 2 arch/x86/kernel/Makefile | 2 arch/x86/kernel/Makefile | 2 arch/x86/kernel/Makefile | 2 arch/x86/kernel/Makefile | 2 arch/x86/kernel/dumpstack.c | 319 +++++++++++++++++++++++++++++++++++++++++ arch/x86/kernel/dumpstack.h | 39 +++++ arch/x86/kernel/dumpstack_32.c | 294 ------------------------------------- arch/x86/kernel/dumpstack_64.c | 285 ------------------------------------ 5 files changed, 363 insertions(+), 576 deletions(-)
-
- 22 10月, 2008 5 次提交
-
-
由 Alexander van Heukelum 提交于
Make i386's die() equal to x86_64's version. Whitespace-only changes on x86_64, to make it equal to i386's version. (user_mode and user_mode_vm are equal on x86_64.) Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Acked-by: NNeil Horman <nhorman@tuxdriver.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
Use oops_begin and oops_end in die_nmi. Whitespace-only changes on x86_64, to make it equal to i386's version. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Acked-by: NNeil Horman <nhorman@tuxdriver.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
Always call oops_exit from oops_end, even if signr==0. Also, move add_taint(TAINT_DIE) from __die to oops_end on x86_64 and interchange two lines to make oops_end more similar to the i386-version. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Acked-by: NNeil Horman <nhorman@tuxdriver.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
oops_end is preceded by either a call to __die, or a conditional call to crash_kexec. Move the conditional call to crash_kexec from the end of __die to the start of oops_end and remove the superfluous call to crash_kexec in die_nmi. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Acked-by: NNeil Horman <nhorman@tuxdriver.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
Change oops_end such that signr=0 signals that do_exit is not to be called. Currently, each use of __die is soon followed by a call to oops_end and 'regs' is set to NULL if oops_end is expected not to call do_exit. Change all such pairs to set signr=0 instead. On x86_64 oops_end is used 'bare' in die_nmi; use signr=0 instead of regs=NULL there, too. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Acked-by: NNeil Horman <nhorman@tuxdriver.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 17 10月, 2008 1 次提交
-
-
由 Andrew Morton 提交于
Print the name of the last-accessed sysfs file when we oops, to help track down oopses which occur in sysfs store/read handlers. Because these oopses tend to not leave any trace of the offending code in the stack traces. Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
-
- 13 10月, 2008 7 次提交
-
-
由 Alexander van Heukelum 提交于
After "dumpstack: x86: various small unification steps", the assembler gives the following compile error. The error is in dumpstack_64.c. {standard input}: Assembler messages: {standard input}:720: Error: Incorrect register `%rbx' used with `l' suffix {standard input}:1340: Error: Incorrect register `%r12' used with `l' suffix Indeed the suffix in get_bp() was wrong. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
- define STACKSLOTS_PER_LINE and use it - define get_bp macro to hide the %%ebp/%%rbp difference - i386: check task==NULL in dump_trace, like x86_64 - i386: show_trace(NULL, ...) uses current automatically - x86_64: use [#%d] for die_counter, like i386 - whitespace and comments Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
- x86: Write log_lvl strings if available - start raw stack dumps on new line - i386: Remove extra indentation for raw stack dumps Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
- i386 and x86_64: always printk the 'data' parameter - i386: announce stack switch (irq -> normal) - i386: check if there is a stack switch before announcing it There is a warning that 'context' might come out corrupt in early boot. If this is true it should be fixed, not worked around. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
- Add "end" parameter to valid_stack_ptr and print_context_stack - use sizeof(long) as the size of a word on the stack Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
- x86_64: use %p to print an address - make i386-version the same as the above The result should be the same on x86_64; on i386 the output only changes if CONFIG_KALLSYMS is turned off, in which case the address is printed twice. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Alexander van Heukelum 提交于
The dumpstack code is logically quite independent from the hardware traps. Split it out into its own file. Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-