Patches contributed by Eötvös Lorand University
commit 60d970c254b95ec7a0fc4c590b510253987b64a0
Author: Ingo Molnar <mingo@elte.hu>
Date: Thu Aug 13 23:37:26 2009 +0200
tracing: Fix syscall tracing on !HAVE_FTRACE_SYSCALLS architectures
The new syscall_regfunc()/unregfunc() functions rely on
the existence of TIF_SYSCALL_FTRACE - but that TIF flag
is only offered by HAVE_FTRACE_SYSCALLS.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 070a42bb8920..35dd27adb82c 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -579,6 +579,8 @@ __initcall(init_tracepoints);
#endif /* CONFIG_MODULES */
+#ifdef CONFIG_FTRACE_SYSCALLS
+
static DEFINE_MUTEX(regfunc_mutex);
static int sys_tracepoint_refcount;
@@ -615,3 +617,4 @@ void syscall_unregfunc(void)
}
mutex_unlock(®func_mutex);
}
+#endif
commit 28402971d869e26271b25301011f667d3a5640c3
Author: Ingo Molnar <mingo@elte.hu>
Date: Thu Aug 13 10:13:22 2009 +0200
perf_counter: Provide hw_perf_counter_setup_online() APIs
Provide weak aliases for hw_perf_counter_setup_online(). This is
used by the BTS patches (for v2.6.32), but it interacts with
fixes so propagate this upstream. (it has no effect as of yet)
Also export perf_counter_output() to architecture code.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index a9d823a93fe8..2b36afe6ae0f 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -694,6 +694,8 @@ struct perf_sample_data {
extern int perf_counter_overflow(struct perf_counter *counter, int nmi,
struct perf_sample_data *data);
+extern void perf_counter_output(struct perf_counter *counter, int nmi,
+ struct perf_sample_data *data);
/*
* Return 1 for a software counter, 0 for a hardware counter
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index b0b20a07f394..e26d2fcfa320 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -88,6 +88,7 @@ void __weak hw_perf_disable(void) { barrier(); }
void __weak hw_perf_enable(void) { barrier(); }
void __weak hw_perf_counter_setup(int cpu) { barrier(); }
+void __weak hw_perf_counter_setup_online(int cpu) { barrier(); }
int __weak
hw_perf_group_sched_in(struct perf_counter *group_leader,
@@ -2630,7 +2631,7 @@ static u32 perf_counter_tid(struct perf_counter *counter, struct task_struct *p)
return task_pid_nr_ns(p, counter->ns);
}
-static void perf_counter_output(struct perf_counter *counter, int nmi,
+void perf_counter_output(struct perf_counter *counter, int nmi,
struct perf_sample_data *data)
{
int ret;
@@ -4592,6 +4593,11 @@ perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
perf_counter_init_cpu(cpu);
break;
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ hw_perf_counter_setup_online(cpu);
+ break;
+
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
perf_counter_exit_cpu(cpu);
@@ -4616,6 +4622,8 @@ void __init perf_counter_init(void)
{
perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
(void *)(long)smp_processor_id());
+ perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
+ (void *)(long)smp_processor_id());
register_cpu_notifier(&perf_cpu_nb);
}
commit 04da8a43da804723a550f00dd158fd5b5e25ae35
Author: Ingo Molnar <mingo@elte.hu>
Date: Tue Aug 11 10:40:08 2009 +0200
perf_counter, x86: Fix/improve apic fallback
Johannes Stezenbach reported that his Pentium-M based
laptop does not have the local APIC enabled by default,
and hence perfcounters do not get initialized.
Add a fallback for this case: allow non-sampled counters
and return with an error on sampled counters. This allows
'perf stat' to work out of box - and allows 'perf top'
and 'perf record' to fall back on a hrtimer based sampling
method.
( Passing 'lapic' on the boot line will allow hardware
sampling to occur - but if the APIC is disabled
permanently by the hardware then this fallback still
allows more systems to use perfcounters. )
Also decouple perfcounter support from X86_LOCAL_APIC.
-v2: fix typo breaking counters on all other systems ...
Reported-by: Johannes Stezenbach <js@sig21.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 738bdc6b0f8b..13ffa5df37d7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -24,6 +24,7 @@ config X86
select HAVE_UNSTABLE_SCHED_CLOCK
select HAVE_IDE
select HAVE_OPROFILE
+ select HAVE_PERF_COUNTERS if (!M386 && !M486)
select HAVE_IOREMAP_PROT
select HAVE_KPROBES
select ARCH_WANT_OPTIONAL_GPIOLIB
@@ -742,7 +743,6 @@ config X86_UP_IOAPIC
config X86_LOCAL_APIC
def_bool y
depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
- select HAVE_PERF_COUNTERS if (!M386 && !M486)
config X86_IO_APIC
def_bool y
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index fffc126dbdf0..900332b800f8 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -55,6 +55,7 @@ struct x86_pmu {
int num_counters_fixed;
int counter_bits;
u64 counter_mask;
+ int apic;
u64 max_period;
u64 intel_ctrl;
};
@@ -613,6 +614,7 @@ static DEFINE_MUTEX(pmc_reserve_mutex);
static bool reserve_pmc_hardware(void)
{
+#ifdef CONFIG_X86_LOCAL_APIC
int i;
if (nmi_watchdog == NMI_LOCAL_APIC)
@@ -627,9 +629,11 @@ static bool reserve_pmc_hardware(void)
if (!reserve_evntsel_nmi(x86_pmu.eventsel + i))
goto eventsel_fail;
}
+#endif
return true;
+#ifdef CONFIG_X86_LOCAL_APIC
eventsel_fail:
for (i--; i >= 0; i--)
release_evntsel_nmi(x86_pmu.eventsel + i);
@@ -644,10 +648,12 @@ static bool reserve_pmc_hardware(void)
enable_lapic_nmi_watchdog();
return false;
+#endif
}
static void release_pmc_hardware(void)
{
+#ifdef CONFIG_X86_LOCAL_APIC
int i;
for (i = 0; i < x86_pmu.num_counters; i++) {
@@ -657,6 +663,7 @@ static void release_pmc_hardware(void)
if (nmi_watchdog == NMI_LOCAL_APIC)
enable_lapic_nmi_watchdog();
+#endif
}
static void hw_perf_counter_destroy(struct perf_counter *counter)
@@ -748,6 +755,15 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
hwc->sample_period = x86_pmu.max_period;
hwc->last_period = hwc->sample_period;
atomic64_set(&hwc->period_left, hwc->sample_period);
+ } else {
+ /*
+ * If we have a PMU initialized but no APIC
+ * interrupts, we cannot sample hardware
+ * counters (user-space has to fall back and
+ * sample via a hrtimer based software counter):
+ */
+ if (!x86_pmu.apic)
+ return -EOPNOTSUPP;
}
counter->destroy = hw_perf_counter_destroy;
@@ -1449,18 +1465,22 @@ void smp_perf_pending_interrupt(struct pt_regs *regs)
void set_perf_counter_pending(void)
{
+#ifdef CONFIG_X86_LOCAL_APIC
apic->send_IPI_self(LOCAL_PENDING_VECTOR);
+#endif
}
void perf_counters_lapic_init(void)
{
- if (!x86_pmu_initialized())
+#ifdef CONFIG_X86_LOCAL_APIC
+ if (!x86_pmu.apic || !x86_pmu_initialized())
return;
/*
* Always use NMI for PMU
*/
apic_write(APIC_LVTPC, APIC_DM_NMI);
+#endif
}
static int __kprobes
@@ -1484,7 +1504,9 @@ perf_counter_nmi_handler(struct notifier_block *self,
regs = args->regs;
+#ifdef CONFIG_X86_LOCAL_APIC
apic_write(APIC_LVTPC, APIC_DM_NMI);
+#endif
/*
* Can't rely on the handled return value to say it was our NMI, two
* counters could trigger 'simultaneously' raising two back-to-back NMIs.
@@ -1515,6 +1537,7 @@ static struct x86_pmu p6_pmu = {
.event_map = p6_pmu_event_map,
.raw_event = p6_pmu_raw_event,
.max_events = ARRAY_SIZE(p6_perfmon_event_map),
+ .apic = 1,
.max_period = (1ULL << 31) - 1,
.version = 0,
.num_counters = 2,
@@ -1541,6 +1564,7 @@ static struct x86_pmu intel_pmu = {
.event_map = intel_pmu_event_map,
.raw_event = intel_pmu_raw_event,
.max_events = ARRAY_SIZE(intel_perfmon_event_map),
+ .apic = 1,
/*
* Intel PMCs cannot be accessed sanely above 32 bit width,
* so we install an artificial 1<<31 period regardless of
@@ -1564,6 +1588,7 @@ static struct x86_pmu amd_pmu = {
.num_counters = 4,
.counter_bits = 48,
.counter_mask = (1ULL << 48) - 1,
+ .apic = 1,
/* use highest bit to detect overflow */
.max_period = (1ULL << 47) - 1,
};
@@ -1589,13 +1614,14 @@ static int p6_pmu_init(void)
return -ENODEV;
}
+ x86_pmu = p6_pmu;
+
if (!cpu_has_apic) {
pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n");
- return -ENODEV;
+ pr_info("no hardware sampling interrupt available.\n");
+ x86_pmu.apic = 0;
}
- x86_pmu = p6_pmu;
-
return 0;
}
commit 89034bc2c7b839702c00a704e79d112737f98be0
Merge: fb82ad719831 85dfd81dc57e
Author: Ingo Molnar <mingo@elte.hu>
Date: Tue Aug 11 14:19:09 2009 +0200
Merge branch 'linus' into tracing/core
Conflicts:
kernel/trace/trace_events_filter.c
We use the tracing/core version.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --cc include/linux/ftrace_event.h
index 26d3673d5143,a81170de7f6b..ac8c6f8cf242
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@@ -118,14 -118,12 +120,12 @@@ struct ftrace_event_call
int (*define_fields)(void);
struct list_head fields;
int filter_active;
- void *filter;
+ struct event_filter *filter;
void *mod;
- #ifdef CONFIG_EVENT_PROFILE
- atomic_t profile_count;
- int (*profile_enable)(struct ftrace_event_call *);
- void (*profile_disable)(struct ftrace_event_call *);
- #endif
+ atomic_t profile_count;
+ int (*profile_enable)(struct ftrace_event_call *);
+ void (*profile_disable)(struct ftrace_event_call *);
};
#define MAX_FILTER_PRED 32
commit f64ccccb8afa43abdd63fcbd230f818d6ea0883f
Author: Ingo Molnar <mingo@elte.hu>
Date: Tue Aug 11 10:26:33 2009 +0200
perf_counter, x86: Fix generic cache events on P6-mobile CPUs
Johannes Stezenbach reported that 'perf stat' does not count
cache-miss and cache-references events on his Pentium-M based
laptop.
This is because we left them blank in p6_perfmon_event_map[],
fill them in.
Reported-by: Johannes Stezenbach <js@sig21.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index 40e233a24d9f..fffc126dbdf0 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -72,8 +72,8 @@ static const u64 p6_perfmon_event_map[] =
{
[PERF_COUNT_HW_CPU_CYCLES] = 0x0079,
[PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,
- [PERF_COUNT_HW_CACHE_REFERENCES] = 0x0000,
- [PERF_COUNT_HW_CACHE_MISSES] = 0x0000,
+ [PERF_COUNT_HW_CACHE_REFERENCES] = 0x0f2e,
+ [PERF_COUNT_HW_CACHE_MISSES] = 0x012e,
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x00c4,
[PERF_COUNT_HW_BRANCH_MISSES] = 0x00c5,
[PERF_COUNT_HW_BUS_CYCLES] = 0x0062,
commit 3c581a7f94542341bf0da496a226b44ac63521a8
Author: Ingo Molnar <mingo@elte.hu>
Date: Tue Aug 11 10:47:36 2009 +0200
perf_counter, x86: Fix lapic printk message
Instead of this garbled bootup on UP Pentium-M systems:
[ 0.015048] Performance Counters:
[ 0.016004] no Local APIC, try rebooting with lapicno PMU driver, software counters only.
Print:
[ 0.015050] Performance Counters:
[ 0.016004] no APIC, boot with the "lapic" boot parameter to force-enable it.
[ 0.017003] no PMU driver, software counters only.
Cf: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index a7aa8f900954..40e233a24d9f 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -1590,7 +1590,7 @@ static int p6_pmu_init(void)
}
if (!cpu_has_apic) {
- pr_info("no Local APIC, try rebooting with lapic");
+ pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n");
return -ENODEV;
}
commit e3560336be655c6791316482fe288b119f34c427
Merge: 26528e773ecc 7b2aa037e878
Author: Ingo Molnar <mingo@elte.hu>
Date: Sun Aug 9 12:46:45 2009 +0200
Merge branch 'linus' into tracing/urgent
Merge reason: Merge up to almost-rc6 to pick up latest perfcounters
(on which we'll queue up a dependent fix)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
commit 72c4d8530244264317a662de9a55cc47e6c8e9df
Author: Ingo Molnar <mingo@elte.hu>
Date: Mon Aug 3 08:47:07 2009 +0200
x86: Introduce GDT_ENTRY_INIT(), fix APM
This crash:
[ 0.891983] calling cache_sysfs_init+0x0/0x1ee @ 1
[ 0.897251] initcall cache_sysfs_init+0x0/0x1ee returned 0 after 405 usecs
[ 0.904019] calling mce_init_device+0x0/0x242 @ 1
[ 0.909124] initcall mce_init_device+0x0/0x242 returned 0 after 347 usecs
[ 0.915815] calling apm_init+0x0/0x38d @ 1
[ 0.919967] apm: BIOS version 1.2 Flags 0x07 (Driver version 1.16ac)
[ 0.926813] general protection fault: 0000 [#1]
[ 0.927269] last sysfs file:
[ 0.927269] Modules linked in:
[ 0.927269]
[ 0.927269] Pid: 271, comm: kapmd Not tainted (2.6.31-rc3-00100-gd520da1-dirty #311) System Product Name
[ 0.927269] EIP: 00c0:[<000082b2>] EFLAGS: 00010002 CPU: 0
[ 0.927269] EIP is at 0x82b2
[ 0.927269] EAX: 0000530e EBX: 00000000 ECX: 00000102 EDX: 00000000
[ 0.927269] ESI: 00000000 EDI: f6a4bf44 EBP: 67890000 ESP: f6a4beec
[ 0.927269] DS: 00c8 ES: 0000 FS: 0000 GS: 0000 SS: 0068
[ 0.927269] Process kapmd (pid: 271, ti=f6a4a000 task=f7142280 task.ti=f6a4a000)
[ 0.927269] Stack:
[ 0.927269] 0000828d 02160000 00b88092 f6a4bf3c c102a63d 00000060 f6a4bf3c f6a4bf44
[ 0.927269] <0> 0000007b 0000007b 00000000 00000000 00000000 00000000 560aae9e 00000000
[ 0.927269] <0> 00000200 f705fd74 00000000 c102af70 f6a4bf60 c102a6ec 0000530e 00000000
[ 0.927269] Call Trace:
[ 0.927269] [<c102a63d>] ? __apm_bios_call_simple+0x7d/0x110
[ 0.927269] [<c102af70>] ? apm+0x0/0x6a0
[ 0.927269] [<c102a6ec>] ? apm_bios_call_simple+0x1c/0x50
[ 0.927269] [<c102b3f5>] ? apm+0x485/0x6a0
[ 0.927269] [<c1038e7a>] ? finish_task_switch+0x2a/0xb0
[ 0.927269] [<c164a69e>] ? schedule+0x31e/0x480
[ 0.927269] [<c102af70>] ? apm+0x0/0x6a0
[ 0.927269] [<c102af70>] ? apm+0x0/0x6a0
[ 0.927269] [<c1052654>] ? kthread+0x74/0x80
[ 0.927269] [<c10525e0>] ? kthread+0x0/0x80
[ 0.927269] [<c101d627>] ? kernel_thread_helper+0x7/0x10
[ 0.927269] Code: Bad EIP value.
[ 0.927269] EIP: [<000082b2>] 0x82b2 SS:ESP 0068:f6a4beec
[ 0.927269] ---[ end trace a7919e7f17c0a725 ]---
[ 0.927269] Kernel panic - not syncing: Fatal exception
[ 0.927269] Pid: 271, comm: kapmd Tainted: G D 2.6.31-rc3-00100-gd520da1-dirty #311
Is caused by an incorrect GDT_ENTRY_INIT() conversion in the apm
code, as noticed by hpa.
Reported-by: Ingo Molnar <mingo@elte.hu>
Noticed-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
LKML-Reference: <20090808094905.GA2954@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 8c9bc287f8fb..b5764a269645 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -106,7 +106,7 @@ DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
/* 16-bit code */
[GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
/* data */
- [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
+ [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff),
[GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
[GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
commit 0bf52b981770cbf006323bab5177f2858a196766
Author: Ingo Molnar <mingo@elte.hu>
Date: Tue Aug 4 21:16:58 2009 +0000
net: Fix spinlock use in alloc_netdev_mq()
-tip testing found this lockdep warning:
[ 2.272010] calling net_dev_init+0x0/0x164 @ 1
[ 2.276033] device class 'net': registering
[ 2.280191] INFO: trying to register non-static key.
[ 2.284005] the code is fine but needs lockdep annotation.
[ 2.284005] turning off the locking correctness validator.
[ 2.284005] Pid: 1, comm: swapper Not tainted 2.6.31-rc5-tip #1145
[ 2.284005] Call Trace:
[ 2.284005] [<7958eb4e>] ? printk+0xf/0x11
[ 2.284005] [<7904f83c>] __lock_acquire+0x11b/0x622
[ 2.284005] [<7908c9b7>] ? alloc_debug_processing+0xf9/0x144
[ 2.284005] [<7904e2be>] ? mark_held_locks+0x3a/0x52
[ 2.284005] [<7908dbc4>] ? kmem_cache_alloc+0xa8/0x13f
[ 2.284005] [<7904e475>] ? trace_hardirqs_on_caller+0xa2/0xc3
[ 2.284005] [<7904fdf6>] lock_acquire+0xb3/0xd0
[ 2.284005] [<79489678>] ? alloc_netdev_mq+0xf5/0x1ad
[ 2.284005] [<79591514>] _spin_lock_bh+0x2d/0x5d
[ 2.284005] [<79489678>] ? alloc_netdev_mq+0xf5/0x1ad
[ 2.284005] [<79489678>] alloc_netdev_mq+0xf5/0x1ad
[ 2.284005] [<793a38f2>] ? loopback_setup+0x0/0x74
[ 2.284005] [<798eecd0>] loopback_net_init+0x20/0x5d
[ 2.284005] [<79483efb>] register_pernet_device+0x23/0x4b
[ 2.284005] [<798f5c9f>] net_dev_init+0x115/0x164
[ 2.284005] [<7900104f>] do_one_initcall+0x4a/0x11a
[ 2.284005] [<798f5b8a>] ? net_dev_init+0x0/0x164
[ 2.284005] [<79066f6d>] ? register_irq_proc+0x8c/0xa8
[ 2.284005] [<798cc29a>] do_basic_setup+0x42/0x52
[ 2.284005] [<798cc30a>] kernel_init+0x60/0xa1
[ 2.284005] [<798cc2aa>] ? kernel_init+0x0/0xa1
[ 2.284005] [<79003e03>] kernel_thread_helper+0x7/0x10
[ 2.284078] device: 'lo': device_add
[ 2.288248] initcall net_dev_init+0x0/0x164 returned 0 after 11718 usecs
[ 2.292010] calling neigh_init+0x0/0x66 @ 1
[ 2.296010] initcall neigh_init+0x0/0x66 returned 0 after 0 usecs
it's using an zero-initialized spinlock. This is a side-effect of:
dev_unicast_init(dev);
in alloc_netdev_mq() making use of dev->addr_list_lock.
The device has just been allocated freshly, it's not accessible
anywhere yet so no locking is needed at all - in fact it's wrong
to lock it here (the lock isnt initialized yet).
This bug was introduced via:
| commit a6ac65db2329e7685299666f5f7b6093c7b0f3a0
| Date: Thu Jul 30 01:06:12 2009 +0000
|
| net: restore the original spinlock to protect unicast list
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jiri Pirko <jpirko@redhat.com>
Tested-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev.c b/net/core/dev.c
index 43e61ba7bd95..6a94475aee85 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4007,9 +4007,7 @@ static void dev_unicast_flush(struct net_device *dev)
static void dev_unicast_init(struct net_device *dev)
{
- netif_addr_lock_bh(dev);
__hw_addr_init(&dev->uc);
- netif_addr_unlock_bh(dev);
}
commit f26542600e605482a1231c44ddb2966d69bd09b0
Author: Ingo Molnar <mingo@elte.hu>
Date: Mon Jun 29 10:40:20 2009 +0200
perf_counter: Set the CONFIG_PERF_COUNTERS default to y if CONFIG_PROFILING=y
If user has already enabled profiling support in the kernel
(for oprofile, old-style profiling of ftrace) then offer up
perfcounters with a y default in interactive kconfig sessions.
Still keep it off by default otherwise.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/init/Kconfig b/init/Kconfig
index 823ee0a2d2a3..3f7e60995c80 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -940,6 +940,7 @@ menu "Performance Counters"
config PERF_COUNTERS
bool "Kernel Performance Counters"
+ default y if PROFILING
depends on HAVE_PERF_COUNTERS
select ANON_INODES
help