This patch adds latency tracing for critical timings.
In /debugfs/tracing/ three files are added:
max_irq_latency
holds the max latency thus far (in usecs)
(default to large number so one must start latency tracing)
irq_thresh
threshold (in usecs) to always print out if irqs off
is detected to be longer than stated here.
If irq_thresh is non-zero, then max_irq_latency
is ignored.
irqsoff_trace
Trace of where the latecy was detected.
irqsoff_fn_trace_ctrl
0 - don't use mcount
1 - use mcount to trace
Here's an example of a trace with irqsoff_fn_trace_ctrl == 0
=======
preemption latency trace v1.1.5 on 2.6.24-rc7
--------------------------------------------------------------------
latency: 100 us, #3/3, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
-----------------
| task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
-----------------
=> started at: _spin_lock_irqsave+0x2a/0xb7
=> ended at: _spin_unlock_irqrestore+0x32/0x5f
_------=> CPU#
/ _-----=> irqs-off
| / _----=> need-resched
|| / _---=> hardirq/softirq
||| / _--=> preempt-depth
|||| /
||||| delay
cmd pid ||||| time | caller
\ / ||||| \ | /
swapper-0 1d.s3 0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
swapper-0 1d.s3 100us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
swapper-0 1d.s3 100us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)
vim:ft=help
=======
And this is a trace with irqsoff_fn_trace_ctrl == 1
=======
preemption latency trace v1.1.5 on 2.6.24-rc7
--------------------------------------------------------------------
latency: 102 us, #12/12, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
-----------------
| task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
-----------------
=> started at: _spin_lock_irqsave+0x2a/0xb7
=> ended at: _spin_unlock_irqrestore+0x32/0x5f
_------=> CPU#
/ _-----=> irqs-off
| / _----=> need-resched
|| / _---=> hardirq/softirq
||| / _--=> preempt-depth
|||| /
||||| delay
cmd pid ||||| time | caller
\ / ||||| \ | /
swapper-0 1dNs3 0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
swapper-0 1dNs3 46us : e1000_read_phy_reg+0x16/0x225 [e1000] (e1000_update_stats+0x5e2/0x64c [e1000])
swapper-0 1dNs3 46us : e1000_swfw_sync_acquire+0x10/0x99 [e1000] (e1000_read_phy_reg+0x49/0x225 [e1000])
swapper-0 1dNs3 46us : e1000_get_hw_eeprom_semaphore+0x12/0xa6 [e1000] (e1000_swfw_sync_acquire+0x36/0x99 [e1000])
swapper-0 1dNs3 47us : __const_udelay+0x9/0x47 (e1000_read_phy_reg+0x116/0x225 [e1000])
swapper-0 1dNs3 47us+: __delay+0x9/0x50 (__const_udelay+0x45/0x47)
swapper-0 1dNs3 97us : preempt_schedule+0xc/0x84 (__delay+0x4e/0x50)
swapper-0 1dNs3 98us : e1000_swfw_sync_release+0xc/0x55 [e1000] (e1000_read_phy_reg+0x211/0x225 [e1000])
swapper-0 1dNs3 99us+: e1000_put_hw_eeprom_semaphore+0x9/0x35 [e1000] (e1000_swfw_sync_release+0x50/0x55 [e1000])
swapper-0 1dNs3 101us : _spin_unlock_irqrestore+0xe/0x5f (e1000_update_stats+0x641/0x64c [e1000])
swapper-0 1dNs3 102us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
swapper-0 1dNs3 102us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)
vim:ft=help
=======
Signed-off-by: Steven Rostedt <[email protected]>
---
arch/x86/kernel/process_64.c | 3
arch/x86/lib/thunk_64.S | 18 +
include/asm-x86/irqflags_32.h | 4
include/asm-x86/irqflags_64.h | 4
include/linux/irqflags.h | 37 ++
include/linux/mcount.h | 29 +-
kernel/fork.c | 2
kernel/lockdep.c | 25 +
lib/tracing/Kconfig | 20 +
lib/tracing/Makefile | 1
lib/tracing/trace_function.c | 89 +-----
lib/tracing/trace_irqsoff.c | 545 ++++++++++++++++++++++++++++++++++++++++++
lib/tracing/tracer.c | 101 +++++--
lib/tracing/tracer.h | 40 ++-
14 files changed, 792 insertions(+), 126 deletions(-)
Index: linux-compile.git/lib/tracing/Kconfig
===================================================================
--- linux-compile.git.orig/lib/tracing/Kconfig 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/lib/tracing/Kconfig 2008-01-09 17:04:10.000000000 -0500
@@ -21,3 +21,23 @@ config FUNCTION_TRACER
insert a call to an architecture specific __mcount routine,
that the debugging mechanism using this facility will hook by
providing a set of inline routines.
+
+config CRITICAL_IRQSOFF_TIMING
+ bool "Interrupts-off critical section latency timing"
+ default n
+ depends on TRACE_IRQFLAGS_SUPPORT
+ depends on GENERIC_TIME
+ select TRACE_IRQFLAGS
+ help
+ This option measures the time spent in irqs-off critical
+ sections, with microsecond accuracy.
+
+ The default measurement method is a maximum search, which is
+ disabled by default and can be runtime (re-)started
+ via:
+
+ echo 0 > /debug/mctracer/preempt_max_latency
+
+ (Note that kernel size and overhead increases with this option
+ enabled. This option and the preempt-off timing option can be
+ used together or separately.)
Index: linux-compile.git/kernel/lockdep.c
===================================================================
--- linux-compile.git.orig/kernel/lockdep.c 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/kernel/lockdep.c 2008-01-09 17:04:10.000000000 -0500
@@ -39,6 +39,7 @@
#include <linux/irqflags.h>
#include <linux/utsname.h>
#include <linux/hash.h>
+#include <linux/mcount.h>
#include <asm/sections.h>
@@ -2009,7 +2010,7 @@ void early_boot_irqs_on(void)
/*
* Hardirqs will be enabled:
*/
-void trace_hardirqs_on(void)
+void notrace trace_hardirqs_on_caller(unsigned long a0)
{
struct task_struct *curr = current;
unsigned long ip;
@@ -2050,14 +2051,27 @@ void trace_hardirqs_on(void)
curr->hardirq_enable_ip = ip;
curr->hardirq_enable_event = ++curr->irq_events;
debug_atomic_inc(&hardirqs_on_events);
+
+#ifdef CONFIG_CRITICAL_IRQSOFF_TIMING
+ time_hardirqs_on(CALLER_ADDR0, a0);
+#endif
}
+EXPORT_SYMBOL(trace_hardirqs_on_caller);
+void notrace trace_hardirqs_on(void) {
+ trace_hardirqs_on_caller(CALLER_ADDR0);
+}
EXPORT_SYMBOL(trace_hardirqs_on);
+void notrace trace_hardirqs_off(void) {
+ trace_hardirqs_off_caller(CALLER_ADDR0);
+}
+EXPORT_SYMBOL(trace_hardirqs_off);
+
/*
* Hardirqs were disabled:
*/
-void trace_hardirqs_off(void)
+void notrace trace_hardirqs_off_caller(unsigned long a0)
{
struct task_struct *curr = current;
@@ -2075,10 +2089,17 @@ void trace_hardirqs_off(void)
curr->hardirq_disable_ip = _RET_IP_;
curr->hardirq_disable_event = ++curr->irq_events;
debug_atomic_inc(&hardirqs_off_events);
+#ifdef CONFIG_CRITICAL_IRQSOFF_TIMING
+ time_hardirqs_off(CALLER_ADDR0, a0);
+#endif
} else
debug_atomic_inc(&redundant_hardirqs_off);
}
+void notrace trace_hardirqs_off(void) {
+ trace_hardirqs_off_caller(CALLER_ADDR0);
+}
+
EXPORT_SYMBOL(trace_hardirqs_off);
/*
Index: linux-compile.git/lib/tracing/trace_irqsoff.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-compile.git/lib/tracing/trace_irqsoff.c 2008-01-09 17:04:10.000000000 -0500
@@ -0,0 +1,545 @@
+/*
+ * trace irqs off criticall timings
+ *
+ * Copyright (C) 2007 Steven Rostedt <[email protected]>
+ *
+ * From code in the latency_tracer, that is:
+ *
+ * Copyright (C) 2004-2006 Ingo Molnar
+ * Copyright (C) 2004 William Lee Irwin III
+ */
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/mcount.h>
+
+#include "tracer.h"
+
+static struct tracing_trace irqsoff_trace;
+static struct tracing_trace max_tr __read_mostly;
+static DEFINE_PER_CPU(struct tracing_trace_cpu, irqsoff_trace_cpu);
+static DEFINE_PER_CPU(struct tracing_trace_cpu, max_data);
+static unsigned long preempt_max_latency = (cycle_t)ULONG_MAX;
+static unsigned long preempt_thresh;
+static __cacheline_aligned_in_smp DEFINE_MUTEX(max_mutex);
+
+/*
+ * max trace is switched with this buffer.
+ */
+static void *max_buffer;
+
+/*
+ * Sequence count - we record it when starting a measurement and
+ * skip the latency if the sequence has changed - some other section
+ * did a maximum and could disturb our measurement with serial console
+ * printouts, etc. Truly coinciding maximum latencies should be rare
+ * and what happens together happens separately as well, so this doesnt
+ * decrease the validity of the maximum found:
+ */
+static __cacheline_aligned_in_smp unsigned long max_sequence;
+
+/*
+ * Should this new latency be reported/recorded?
+ */
+static int notrace report_latency(cycle_t delta)
+{
+ if (preempt_thresh) {
+ if (delta < preempt_thresh)
+ return 0;
+ } else {
+ if (delta <= preempt_max_latency)
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * Copy the new maximum trace into the separate maximum-trace
+ * structure. (this way the maximum trace is permanently saved,
+ * for later retrieval via /proc/latency_trace)
+ */
+static void update_max_tr(struct tracing_trace *tr,
+ struct tracing_trace_cpu *data,
+ int cpu)
+{
+ struct tracing_trace_cpu *save;
+ int i;
+
+#ifdef CONFIG_PREEMPT
+ WARN_ON(!preempt_count() && !irqs_disabled());
+#endif
+
+ max_tr.cpu = cpu;
+ save = max_tr.data[cpu];
+
+ /* clear out all the previous traces */
+ for_each_possible_cpu(i) {
+ if (max_tr.data[i]->trace)
+ max_tr.data[i]->trace = NULL;
+ }
+
+ max_tr.time_start = data->preempt_timestamp;
+
+ memcpy(save, data, sizeof(*data));
+ save->saved_latency = preempt_max_latency;
+
+ memcpy(save->comm, current->comm, TASK_COMM_LEN);
+ save->pid = current->pid;
+ save->uid = current->uid;
+ save->nice = current->static_prio - 20 - MAX_RT_PRIO;
+ save->policy = current->policy;
+ save->rt_priority = current->rt_priority;
+
+ /* from memcpy above: save->trace = data->trace */
+ data->trace = max_buffer;
+ max_buffer = save->trace;
+}
+
+cycle_t notrace usecs_to_cycles(unsigned long usecs);
+
+static void notrace
+check_critical_timing(struct tracing_trace *tr,
+ struct tracing_trace_cpu *data,
+ unsigned long parent_ip,
+ int cpu)
+{
+ unsigned long latency, t0, t1;
+ cycle_t T0, T1, T2, delta;
+ unsigned long flags;
+
+ /*
+ * usecs conversion is slow so we try to delay the conversion
+ * as long as possible:
+ */
+ T0 = data->preempt_timestamp;
+ T1 = now();
+ delta = T1-T0;
+
+ local_save_flags(flags);
+
+ if (!report_latency(delta))
+ goto out;
+
+ tracing_function_trace(tr, data, CALLER_ADDR0, parent_ip, flags);
+ /*
+ * Update the timestamp, because the trace entry above
+ * might change it (it can only get larger so the latency
+ * is fair to be reported):
+ */
+ T2 = now();
+
+ delta = T2-T0;
+
+ latency = cycles_to_usecs(delta);
+
+ if (data->critical_sequence != max_sequence ||
+ !mutex_trylock(&max_mutex))
+ goto out;
+
+ preempt_max_latency = delta;
+ t0 = cycles_to_usecs(T0);
+ t1 = cycles_to_usecs(T1);
+
+ data->critical_end = parent_ip;
+
+ update_max_tr(tr, data, cpu);
+
+ if (preempt_thresh)
+ printk(KERN_INFO "(%16s-%-5d|#%d): %lu us critical section "
+ "violates %lu us threshold.\n"
+ " => started at timestamp %lu: ",
+ current->comm, current->pid,
+ raw_smp_processor_id(),
+ latency, cycles_to_usecs(preempt_thresh), t0);
+ else
+ printk(KERN_INFO "(%16s-%-5d|#%d): new %lu us maximum-latency "
+ "critical section.\n => started at timestamp %lu: ",
+ current->comm, current->pid,
+ raw_smp_processor_id(),
+ latency, t0);
+
+ print_symbol(KERN_CONT "<%s>\n", data->critical_start);
+ printk(KERN_CONT " => ended at timestamp %lu: ", t1);
+ print_symbol(KERN_CONT "<%s>\n", data->critical_end);
+ dump_stack();
+ t1 = cycles_to_usecs(now());
+ printk(KERN_CONT " => dump-end timestamp %lu\n\n", t1);
+
+ max_sequence++;
+
+ mutex_unlock(&max_mutex);
+
+out:
+ data->critical_sequence = max_sequence;
+ data->preempt_timestamp = now();
+ tracing_reset(data);
+ tracing_function_trace(tr, data, CALLER_ADDR0, parent_ip, flags);
+}
+
+static inline void notrace
+start_critical_timing(unsigned long ip, unsigned long parent_ip)
+{
+ int cpu = raw_smp_processor_id();
+ struct tracing_trace *tr = &irqsoff_trace;
+ struct tracing_trace_cpu *data = tr->data[cpu];
+ unsigned long flags;
+
+ if (unlikely(!data) || unlikely(!data->trace) ||
+ data->critical_start || atomic_read(&data->disabled))
+ return;
+
+ atomic_inc(&data->disabled);
+
+ data->critical_sequence = max_sequence;
+ data->preempt_timestamp = now();
+ data->critical_start = ip;
+ tracing_reset(data);
+
+ local_save_flags(flags);
+ tracing_function_trace(tr, data, ip, parent_ip, flags);
+
+ atomic_dec(&data->disabled);
+}
+
+static inline void notrace
+stop_critical_timing(unsigned long ip, unsigned long parent_ip)
+{
+ int cpu = raw_smp_processor_id();
+ struct tracing_trace *tr = &irqsoff_trace;
+ struct tracing_trace_cpu *data = tr->data[cpu];
+ unsigned long flags;
+
+ if (unlikely(!data) || unlikely(!data->trace) ||
+ !data->critical_start || atomic_read(&data->disabled))
+ return;
+
+ atomic_inc(&data->disabled);
+ local_save_flags(flags);
+ tracing_function_trace(tr, data, ip, parent_ip, flags);
+ check_critical_timing(tr, data, ip, cpu);
+ data->critical_start = 0;
+ atomic_dec(&data->disabled);
+}
+
+void notrace start_critical_timings(void)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ start_critical_timing(CALLER_ADDR0, 0);
+}
+
+void notrace stop_critical_timings(void)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ stop_critical_timing(CALLER_ADDR0, 0);
+}
+
+#ifdef CONFIG_LOCKDEP
+void notrace time_hardirqs_on(unsigned long a0, unsigned long a1)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ stop_critical_timing(a0, a1);
+}
+
+void notrace time_hardirqs_off(unsigned long a0, unsigned long a1)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ start_critical_timing(a0, a1);
+}
+
+#else /* !CONFIG_LOCKDEP */
+
+/*
+ * Stubs:
+ */
+
+void early_boot_irqs_off(void)
+{
+}
+
+void early_boot_irqs_on(void)
+{
+}
+
+void trace_softirqs_on(unsigned long ip)
+{
+}
+
+void trace_softirqs_off(unsigned long ip)
+{
+}
+
+inline void print_irqtrace_events(struct task_struct *curr)
+{
+}
+
+/*
+ * We are only interested in hardirq on/off events:
+ */
+void notrace trace_hardirqs_on(void)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ stop_critical_timing(CALLER_ADDR0, 0);
+}
+EXPORT_SYMBOL(trace_hardirqs_on);
+
+void notrace trace_hardirqs_off(void)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ start_critical_timing(CALLER_ADDR0, 0);
+}
+EXPORT_SYMBOL(trace_hardirqs_off);
+
+void notrace trace_hardirqs_on_caller(unsigned long caller_addr)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ stop_critical_timing(CALLER_ADDR0, caller_addr);
+}
+EXPORT_SYMBOL(trace_hardirqs_on_caller);
+
+void notrace trace_hardirqs_off_caller(unsigned long caller_addr)
+{
+ unsigned long flags;
+
+ local_save_flags(flags);
+
+ if (irqs_disabled_flags(flags))
+ start_critical_timing(CALLER_ADDR0, caller_addr);
+}
+EXPORT_SYMBOL(trace_hardirqs_off_caller);
+
+#endif /* CONFIG_LOCKDEP */
+
+
+static void notrace irqsoff_trace_call(unsigned long ip,
+ unsigned long parent_ip)
+{
+ struct tracing_trace *tr = &irqsoff_trace;
+ struct tracing_trace_cpu *data;
+ unsigned long flags;
+ int cpu;
+
+ local_save_flags(flags);
+
+ if (!irqs_disabled_flags(flags))
+ return;
+
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ atomic_inc(&data->disabled);
+
+ if (likely(atomic_read(&data->disabled) == 1))
+ tracing_function_trace(tr, data, ip, parent_ip, flags);
+
+ atomic_dec(&data->disabled);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void irqsoff_start(struct tracing_iterator *iter)
+{
+ mutex_lock(&max_mutex);
+}
+
+static void irqsoff_stop(struct tracing_iterator *iter)
+{
+ mutex_unlock(&max_mutex);
+}
+
+static ssize_t max_irq_lat_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ unsigned long *ptr = filp->private_data;
+ char buf[64];
+ int r;
+
+ r = snprintf(buf, 64, "%ld\n", *ptr == -1 ? : cycles_to_usecs(*ptr));
+ if (r > 64)
+ r = 64;
+ return simple_read_from_buffer(ubuf, cnt, ppos,
+ buf, r);
+}
+static ssize_t max_irq_lat_write(struct file *filp,
+ const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ long *ptr = filp->private_data;
+ long val;
+ char buf[64];
+
+ if (cnt > 63)
+ cnt = 63;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ val = simple_strtoul(buf, NULL, 10);
+
+ *ptr = usecs_to_cycles(val);
+
+ return cnt;
+}
+
+static struct file_operations max_irq_lat_fops = {
+ .open = tracing_open_generic,
+ .read = max_irq_lat_read,
+ .write = max_irq_lat_write,
+};
+
+static void irqsoff_trace_ctrl_update(struct tracing_trace *tr,
+ unsigned long val)
+{
+ val = !!val;
+
+ if (tr->ctrl ^ val) {
+ if (val)
+ register_mcount_function(irqsoff_trace_call);
+ else
+ clear_mcount_function();
+ tr->ctrl = val;
+ }
+}
+
+static __init void irqsoff_trace_init_debugfs(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ d_tracer = tracing_init_dentry();
+
+ irqsoff_trace.ctrl_update = irqsoff_trace_ctrl_update;
+
+ entry = debugfs_create_file("irqsoff_fn_trace_ctrl", 0644, d_tracer,
+ &irqsoff_trace, &tracing_ctrl_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs"
+ " 'irqsoff_fn_trace' entry\n");
+
+ entry = debugfs_create_file("max_irq_latency", 0644, d_tracer,
+ &preempt_max_latency, &max_irq_lat_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'ctrl' entry\n");
+
+ entry = debugfs_create_file("irq_thresh", 0644, d_tracer,
+ &preempt_thresh, &max_irq_lat_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'ctrl' entry\n");
+
+ entry = debugfs_create_file("irqsoff_trace", 0444, d_tracer,
+ &max_tr, &tracing_lt_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'irqsoff_trace' entry\n");
+}
+
+#endif /* CONFIG_DEBUGFS */
+
+static void notrace irqsoff_trace_open(struct tracing_iterator *iter)
+{
+#ifdef CONFIG_MCOUNT
+ /* stop the trace while dumping */
+ if (iter->tr->ctrl)
+ clear_mcount_function();
+#endif
+}
+
+static void notrace irqsoff_trace_close(struct tracing_iterator *iter)
+{
+#ifdef CONFIG_MCOUNT
+ if (iter->tr->ctrl)
+ register_mcount_function(irqsoff_trace_call);
+#endif
+}
+
+__init static int trace_irqsoff_alloc_buffers(void)
+{
+ const int order = page_order(TRACING_NR_ENTRIES * TRACING_ENTRY_SIZE);
+ const unsigned long size = (1UL << order) << PAGE_SHIFT;
+ struct tracing_entry *array;
+ int i;
+
+ for_each_possible_cpu(i) {
+ irqsoff_trace.data[i] = &per_cpu(irqsoff_trace_cpu, i);
+ max_tr.data[i] = &per_cpu(max_data, i);
+
+ array = (struct tracing_entry *)
+ __get_free_pages(GFP_KERNEL, order);
+ if (array == NULL) {
+ printk(KERN_ERR "irqsoff tracer: failed to allocate"
+ " %ld bytes for trace buffer!\n", size);
+ goto free_buffers;
+ }
+ irqsoff_trace.data[i]->trace = array;
+ }
+
+ array = (struct tracing_entry *)
+ __get_free_pages(GFP_KERNEL, order);
+ if (array == NULL) {
+ printk(KERN_ERR "irqsoff tracer: failed to allocate"
+ " %ld bytes for trace buffer!\n", size);
+ goto free_buffers;
+ }
+ max_buffer = array;
+
+ /*
+ * Since we allocate by orders of pages, we may be able to
+ * round up a bit.
+ */
+ irqsoff_trace.entries = size / TRACING_ENTRY_SIZE;
+ max_tr.entries = irqsoff_trace.entries;
+ max_tr.start = irqsoff_start;
+ max_tr.stop = irqsoff_stop;
+
+ pr_info("irqs off tracer: %ld bytes allocated for %ld",
+ size, TRACING_NR_ENTRIES);
+ pr_info(" entries of %d bytes\n", (int)TRACING_ENTRY_SIZE);
+ pr_info(" actual entries %ld\n", irqsoff_trace.entries);
+
+ irqsoff_trace_init_debugfs();
+
+ irqsoff_trace.open = irqsoff_trace_open;
+ irqsoff_trace.close = irqsoff_trace_close;
+
+ return 0;
+
+ free_buffers:
+ for (i-- ; i >= 0; i--) {
+ if (irqsoff_trace.data[i] && irqsoff_trace.data[i]->trace) {
+ free_pages((unsigned long)irqsoff_trace.data[i]->trace,
+ order);
+ irqsoff_trace.data[i]->trace = NULL;
+ }
+ }
+ return -ENOMEM;
+}
+
+device_initcall(trace_irqsoff_alloc_buffers);
Index: linux-compile.git/include/linux/mcount.h
===================================================================
--- linux-compile.git.orig/include/linux/mcount.h 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/include/linux/mcount.h 2008-01-09 17:04:10.000000000 -0500
@@ -1,15 +1,36 @@
#ifndef _LINUX_MCOUNT_H
#define _LINUX_MCOUNT_H
+#ifdef CONFIG_FRAME_POINTER
+/* TODO: need to fix this for ARM */
+# define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
+# define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
+# define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
+# define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
+# define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
+# define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
+#else
+# define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
+# define CALLER_ADDR1 0UL
+# define CALLER_ADDR2 0UL
+# define CALLER_ADDR3 0UL
+# define CALLER_ADDR4 0UL
+# define CALLER_ADDR5 0UL
+#endif
+
+#ifdef CONFIG_CRITICAL_IRQSOFF_TIMING
+ extern void notrace time_hardirqs_on(unsigned long a0, unsigned long a1);
+ extern void notrace time_hardirqs_off(unsigned long a0, unsigned long a1);
+#else
+# define time_hardirqs_on(a0, a1) do { } while (0)
+# define time_hardirqs_off(a0, a1) do { } while (0)
+#endif
+
#ifdef CONFIG_MCOUNT
extern int mcount_enabled;
#include <linux/linkage.h>
-#define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
-#define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
-#define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
-
typedef void (*mcount_func_t)(unsigned long ip, unsigned long parent_ip);
extern void mcount(void);
Index: linux-compile.git/lib/tracing/Makefile
===================================================================
--- linux-compile.git.orig/lib/tracing/Makefile 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/lib/tracing/Makefile 2008-01-09 17:04:10.000000000 -0500
@@ -2,5 +2,6 @@ obj-$(CONFIG_MCOUNT) += libmcount.o
obj-$(CONFIG_TRACING) += tracer.o
obj-$(CONFIG_FUNCTION_TRACER) += trace_function.o
+obj-$(CONFIG_CRITICAL_IRQSOFF_TIMING) += trace_irqsoff.o
libmcount-y := mcount.o
Index: linux-compile.git/lib/tracing/trace_function.c
===================================================================
--- linux-compile.git.orig/lib/tracing/trace_function.c 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/lib/tracing/trace_function.c 2008-01-09 17:04:10.000000000 -0500
@@ -23,69 +23,40 @@ static notrace void function_trace_reset
int cpu;
tr->time_start = now();
- tr->saved_latency = 0;
- tr->critical_start = 0;
- tr->critical_end = 0;
-
- for_each_online_cpu(cpu) {
- tr->data[cpu]->trace_idx = 0;
- atomic_set(&tr->data[cpu]->underrun, 0);
- }
-}
-#ifdef CONFIG_DEBUG_FS
-static ssize_t function_trace_ctrl_read(struct file *filp, char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- struct tracing_trace *tr = filp->private_data;
- char buf[16];
- int r;
-
- r = sprintf(buf, "%ld\n", tr->ctrl);
- return simple_read_from_buffer(ubuf, cnt, ppos,
- buf, r);
+ for_each_online_cpu(cpu)
+ tracing_reset(tr->data[cpu]);
}
static void notrace function_trace_call(unsigned long ip,
unsigned long parent_ip)
{
struct tracing_trace *tr = &function_trace;
+ struct tracing_trace_cpu *data;
+ unsigned long flags;
+ int cpu;
- tracing_function_trace(tr, ip, parent_ip);
-}
-
-static ssize_t function_trace_ctrl_write(struct file *filp,
- const char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- struct tracing_trace *tr = filp->private_data;
- long val;
- char buf[16];
-
- if (cnt > 15)
- cnt = 15;
+ raw_local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ atomic_inc(&data->disabled);
- if (copy_from_user(&buf, ubuf, cnt))
- return -EFAULT;
+ if (likely(atomic_read(&data->disabled) == 1))
+ tracing_function_trace(tr, data, ip, parent_ip, flags);
- buf[cnt] = 0;
+ atomic_dec(&data->disabled);
+ raw_local_irq_restore(flags);
+}
- val = !!simple_strtoul(buf, NULL, 10);
+#ifdef CONFIG_DEBUG_FS
+static void function_trace_ctrl_update(struct tracing_trace *tr,
+ unsigned long val)
+{
+ val = !!val;
/* When starting a new trace, reset the buffers */
if (val)
function_trace_reset(tr);
- else {
- /* pretty meaningless for now */
- tr->time_end = now();
- tr->saved_latency = tr->time_end - tr->time_start;
- memcpy(tr->comm, current->comm, TASK_COMM_LEN);
- tr->pid = current->pid;
- tr->uid = current->uid;
- tr->nice = current->static_prio - 20 - MAX_RT_PRIO;
- tr->policy = current->policy;
- tr->rt_priority = current->rt_priority;
- }
if (tr->ctrl ^ val) {
if (val)
@@ -94,18 +65,8 @@ static ssize_t function_trace_ctrl_write
clear_mcount_function();
tr->ctrl = val;
}
-
- filp->f_pos += cnt;
-
- return cnt;
}
-static struct file_operations function_trace_ctrl_fops = {
- .open = tracing_open_generic,
- .read = function_trace_ctrl_read,
- .write = function_trace_ctrl_write,
-};
-
static __init void function_trace_init_debugfs(void)
{
struct dentry *d_tracer;
@@ -113,8 +74,10 @@ static __init void function_trace_init_d
d_tracer = tracing_init_dentry();
+ function_trace.ctrl_update = function_trace_ctrl_update;
+
entry = debugfs_create_file("fn_trace_ctrl", 0644, d_tracer,
- &function_trace, &function_trace_ctrl_fops);
+ &function_trace, &tracing_ctrl_fops);
if (!entry)
pr_warning("Could not create debugfs 'ctrl' entry\n");
@@ -154,12 +117,6 @@ static void function_trace_close(struct
register_mcount_function(function_trace_call);
}
-static notrace int page_order(const unsigned long size)
-{
- const unsigned long nr_pages = DIV_ROUND_UP(size, PAGE_SIZE);
- return ilog2(roundup_pow_of_two(nr_pages));
-}
-
__init static int function_trace_alloc_buffers(void)
{
const int order = page_order(TRACING_NR_ENTRIES * TRACING_ENTRY_SIZE);
@@ -187,7 +144,7 @@ __init static int function_trace_alloc_b
pr_info("function tracer: %ld bytes allocated for %ld",
size, TRACING_NR_ENTRIES);
- pr_info(" entries of %d bytes\n", TRACING_ENTRY_SIZE);
+ pr_info(" entries of %d bytes\n", (int)TRACING_ENTRY_SIZE);
pr_info(" actual entries %ld\n", function_trace.entries);
function_trace_init_debugfs();
Index: linux-compile.git/lib/tracing/tracer.c
===================================================================
--- linux-compile.git.orig/lib/tracing/tracer.c 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/lib/tracing/tracer.c 2008-01-09 17:04:10.000000000 -0500
@@ -44,6 +44,12 @@ enum trace_flag_type {
TRACE_FLAG_IRQS_HARD_OFF = 0x20,
};
+void notrace tracing_reset(struct tracing_trace_cpu *data)
+{
+ data->trace_idx = 0;
+ atomic_set(&data->underrun, 0);
+}
+
static inline notrace struct tracing_entry *
tracing_get_trace_entry(struct tracing_trace *tr,
struct tracing_trace_cpu *data)
@@ -89,30 +95,18 @@ tracing_generic_entry_update(struct trac
}
notrace void tracing_function_trace(struct tracing_trace *tr,
+ struct tracing_trace_cpu *data,
unsigned long ip,
- unsigned long parent_ip)
+ unsigned long parent_ip,
+ unsigned long flags)
{
- unsigned long flags;
- int cpu;
-
- raw_local_irq_save(flags);
- cpu = raw_smp_processor_id();
-
- atomic_inc(&tr->data[cpu]->disabled);
- if (likely(atomic_read(&tr->data[cpu]->disabled) == 1)) {
- struct tracing_entry *entry;
- struct tracing_trace_cpu *data = tr->data[cpu];
-
- entry = tracing_get_trace_entry(tr, data);
- tracing_generic_entry_update(entry, flags);
- entry->type = TRACE_FN;
- entry->fn.ip = ip;
- entry->fn.parent_ip = parent_ip;
- }
-
- atomic_dec(&tr->data[cpu]->disabled);
+ struct tracing_entry *entry;
- raw_local_irq_restore(flags);
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, flags);
+ entry->type = TRACE_FN;
+ entry->fn.ip = ip;
+ entry->fn.parent_ip = parent_ip;
}
#ifdef CONFIG_DEBUG_FS
@@ -231,6 +225,10 @@ static void *s_start(struct seq_file *m,
loff_t l = 0;
int i;
+ /* let the tracer grab locks here if needed */
+ if (iter->tr->start)
+ iter->tr->start(iter);
+
if (*pos != iter->pos) {
iter->ent = NULL;
iter->cpu = 0;
@@ -252,6 +250,11 @@ static void *s_start(struct seq_file *m,
static void s_stop(struct seq_file *m, void *p)
{
+ struct tracing_iterator *iter = m->private;
+
+ /* let the tracer release locks here if needed */
+ if (iter->tr->stop)
+ iter->tr->stop(iter);
}
#ifdef CONFIG_KALLSYMS
@@ -303,6 +306,7 @@ static void notrace print_trace_header(s
struct tracing_iterator *iter)
{
struct tracing_trace *tr = iter->tr;
+ struct tracing_trace_cpu *data = tr->data[tr->cpu];
unsigned long underruns = 0;
unsigned long underrun;
unsigned long entries = 0;
@@ -326,7 +330,7 @@ static void notrace print_trace_header(s
"---------------------------------\n");
seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |"
" (M:%s VP:%d, KP:%d, SP:%d HP:%d",
- cycles_to_usecs(tr->saved_latency),
+ cycles_to_usecs(data->saved_latency),
entries,
(entries + underruns),
smp_processor_id(),
@@ -349,15 +353,15 @@ static void notrace print_trace_header(s
seq_puts(m, " -----------------\n");
seq_printf(m, " | task: %.16s-%d "
"(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n",
- tr->comm, tr->pid, tr->uid, tr->nice,
- tr->policy, tr->rt_priority);
+ data->comm, data->pid, data->uid, data->nice,
+ data->policy, data->rt_priority);
seq_puts(m, " -----------------\n");
- if (tr->critical_start) {
+ if (data->critical_start) {
seq_puts(m, " => started at: ");
- seq_print_ip_sym(m, tr->critical_start, sym_only);
+ seq_print_ip_sym(m, data->critical_start, sym_only);
seq_puts(m, "\n => ended at: ");
- seq_print_ip_sym(m, tr->critical_end, sym_only);
+ seq_print_ip_sym(m, data->critical_end, sym_only);
seq_puts(m, "\n");
}
@@ -700,6 +704,49 @@ static struct file_operations tracing_it
.write = tracing_iter_ctrl_write,
};
+static ssize_t tracing_ctrl_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct tracing_trace *tr = filp->private_data;
+ char buf[64];
+ int r;
+
+ r = sprintf(buf, "%ld\n", tr->ctrl);
+ return simple_read_from_buffer(ubuf, cnt, ppos,
+ buf, r);
+}
+
+static ssize_t tracing_ctrl_write(struct file *filp,
+ const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct tracing_trace *tr = filp->private_data;
+ long val;
+ char buf[64];
+
+ if (cnt > 63)
+ cnt = 63;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ val = simple_strtoul(buf, NULL, 10);
+
+ tr->ctrl_update(tr, val);
+
+ filp->f_pos += cnt;
+
+ return cnt;
+}
+
+struct file_operations tracing_ctrl_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_ctrl_read,
+ .write = tracing_ctrl_write,
+};
+
static struct dentry *d_tracer;
struct dentry *tracing_init_dentry(void)
Index: linux-compile.git/lib/tracing/tracer.h
===================================================================
--- linux-compile.git.orig/lib/tracing/tracer.h 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/lib/tracing/tracer.h 2008-01-09 17:04:10.000000000 -0500
@@ -26,6 +26,17 @@ struct tracing_trace_cpu {
unsigned long trace_idx;
atomic_t disabled;
atomic_t underrun;
+ unsigned long saved_latency;
+ unsigned long critical_start;
+ unsigned long critical_end;
+ unsigned long critical_sequence;
+ unsigned long nice;
+ unsigned long policy;
+ unsigned long rt_priority;
+ cycle_t preempt_timestamp;
+ pid_t pid;
+ uid_t uid;
+ char comm[TASK_COMM_LEN];
};
struct tracing_iterator;
@@ -33,19 +44,14 @@ struct tracing_iterator;
struct tracing_trace {
unsigned long entries;
long ctrl;
- char comm[TASK_COMM_LEN];
- pid_t pid;
- uid_t uid;
- unsigned long nice;
- unsigned long policy;
- unsigned long rt_priority;
- unsigned long saved_latency;
- unsigned long critical_start;
- unsigned long critical_end;
- unsigned long long time_start;
- unsigned long long time_end;
+ int cpu;
+ cycle_t time_start;
void (*open)(struct tracing_iterator *iter);
void (*close)(struct tracing_iterator *iter);
+ void (*start)(struct tracing_iterator *iter);
+ void (*stop)(struct tracing_iterator *iter);
+ void (*ctrl_update)(struct tracing_trace *tr,
+ unsigned long val);
struct tracing_trace_cpu *data[NR_CPUS];
};
@@ -62,18 +68,28 @@ struct tracing_iterator {
#define TRACING_ENTRY_SIZE sizeof(struct tracing_entry)
#define TRACING_NR_ENTRIES (65536UL)
+void notrace tracing_reset(struct tracing_trace_cpu *data);
int tracing_open_generic(struct inode *inode, struct file *filp);
struct dentry *tracing_init_dentry(void);
void tracing_function_trace(struct tracing_trace *tr,
+ struct tracing_trace_cpu *data,
unsigned long ip,
- unsigned long parent_ip);
+ unsigned long parent_ip,
+ unsigned long flags);
extern struct file_operations tracing_fops;
extern struct file_operations tracing_lt_fops;
+extern struct file_operations tracing_ctrl_fops;
static inline notrace cycle_t now(void)
{
return get_monotonic_cycles();
}
+static inline notrace int page_order(const unsigned long size)
+{
+ const unsigned long nr_pages = DIV_ROUND_UP(size, PAGE_SIZE);
+ return ilog2(roundup_pow_of_two(nr_pages));
+}
+
#endif /* _LINUX_MCOUNT_TRACER_H */
Index: linux-compile.git/kernel/fork.c
===================================================================
--- linux-compile.git.orig/kernel/fork.c 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/kernel/fork.c 2008-01-09 17:04:10.000000000 -0500
@@ -1010,7 +1010,7 @@ static struct task_struct *copy_process(
rt_mutex_init_task(p);
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_LOCKDEP)
DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
#endif
Index: linux-compile.git/arch/x86/kernel/process_64.c
===================================================================
--- linux-compile.git.orig/arch/x86/kernel/process_64.c 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/arch/x86/kernel/process_64.c 2008-01-09 17:04:10.000000000 -0500
@@ -233,7 +233,10 @@ void cpu_idle (void)
*/
local_irq_disable();
enter_idle();
+ /* Don't trace irqs off for idle */
+ stop_critical_timings();
idle();
+ start_critical_timings();
/* In many cases the interrupt that ended idle
has already called exit_idle. But some idle
loops can be woken up without interrupt. */
Index: linux-compile.git/arch/x86/lib/thunk_64.S
===================================================================
--- linux-compile.git.orig/arch/x86/lib/thunk_64.S 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/arch/x86/lib/thunk_64.S 2008-01-09 17:04:10.000000000 -0500
@@ -47,8 +47,22 @@
thunk __up_wakeup,__up
#ifdef CONFIG_TRACE_IRQFLAGS
- thunk trace_hardirqs_on_thunk,trace_hardirqs_on
- thunk trace_hardirqs_off_thunk,trace_hardirqs_off
+ /* put return address in rdi (arg1) */
+ .macro thunk_ra name,func
+ .globl \name
+\name:
+ CFI_STARTPROC
+ SAVE_ARGS
+ /* SAVE_ARGS pushs 9 elements */
+ /* the next element would be the rip */
+ movq 9*8(%rsp), %rdi
+ call \func
+ jmp restore
+ CFI_ENDPROC
+ .endm
+
+ thunk_ra trace_hardirqs_on_thunk,trace_hardirqs_on_caller
+ thunk_ra trace_hardirqs_off_thunk,trace_hardirqs_off_caller
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
Index: linux-compile.git/include/linux/irqflags.h
===================================================================
--- linux-compile.git.orig/include/linux/irqflags.h 2008-01-09 17:03:59.000000000 -0500
+++ linux-compile.git/include/linux/irqflags.h 2008-01-09 17:36:00.000000000 -0500
@@ -12,10 +12,21 @@
#define _LINUX_TRACE_IRQFLAGS_H
#ifdef CONFIG_TRACE_IRQFLAGS
- extern void trace_hardirqs_on(void);
- extern void trace_hardirqs_off(void);
+# include <linux/mcount.h>
+ extern void trace_hardirqs_on_caller(unsigned long ip);
+ extern void trace_hardirqs_off_caller(unsigned long ip);
extern void trace_softirqs_on(unsigned long ip);
extern void trace_softirqs_off(unsigned long ip);
+ extern void trace_hardirqs_on(void);
+ extern void trace_hardirqs_off(void);
+ static inline void notrace __trace_hardirqs_on(void)
+ {
+ trace_hardirqs_on_caller(CALLER_ADDR0);
+ }
+ static inline void notrace __trace_hardirqs_off(void)
+ {
+ trace_hardirqs_off_caller(CALLER_ADDR0);
+ }
# define trace_hardirq_context(p) ((p)->hardirq_context)
# define trace_softirq_context(p) ((p)->softirq_context)
# define trace_hardirqs_enabled(p) ((p)->hardirqs_enabled)
@@ -28,6 +39,8 @@
#else
# define trace_hardirqs_on() do { } while (0)
# define trace_hardirqs_off() do { } while (0)
+# define __trace_hardirqs_on() do { } while (0)
+# define __trace_hardirqs_off() do { } while (0)
# define trace_softirqs_on(ip) do { } while (0)
# define trace_softirqs_off(ip) do { } while (0)
# define trace_hardirq_context(p) 0
@@ -41,24 +54,32 @@
# define INIT_TRACE_IRQFLAGS
#endif
+#ifdef CONFIG_CRITICAL_IRQSOFF_TIMING
+ extern void stop_critical_timings(void);
+ extern void start_critical_timings(void);
+#else
+# define stop_critical_timings() do { } while (0)
+# define start_critical_timings() do { } while (0)
+#endif
+
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
#include <asm/irqflags.h>
#define local_irq_enable() \
- do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0)
+ do { __trace_hardirqs_on(); raw_local_irq_enable(); } while (0)
#define local_irq_disable() \
- do { raw_local_irq_disable(); trace_hardirqs_off(); } while (0)
+ do { raw_local_irq_disable(); __trace_hardirqs_off(); } while (0)
#define local_irq_save(flags) \
- do { raw_local_irq_save(flags); trace_hardirqs_off(); } while (0)
+ do { raw_local_irq_save(flags); __trace_hardirqs_off(); } while (0)
#define local_irq_restore(flags) \
do { \
if (raw_irqs_disabled_flags(flags)) { \
raw_local_irq_restore(flags); \
- trace_hardirqs_off(); \
+ __trace_hardirqs_off(); \
} else { \
- trace_hardirqs_on(); \
+ __trace_hardirqs_on(); \
raw_local_irq_restore(flags); \
} \
} while (0)
@@ -76,7 +97,7 @@
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
#define safe_halt() \
do { \
- trace_hardirqs_on(); \
+ __trace_hardirqs_on(); \
raw_safe_halt(); \
} while (0)
Index: linux-compile.git/include/asm-x86/irqflags_32.h
===================================================================
--- linux-compile.git.orig/include/asm-x86/irqflags_32.h 2007-11-12 09:25:50.000000000 -0500
+++ linux-compile.git/include/asm-x86/irqflags_32.h 2008-01-09 17:04:10.000000000 -0500
@@ -139,9 +139,9 @@ static inline int raw_irqs_disabled(void
static inline void trace_hardirqs_fixup_flags(unsigned long flags)
{
if (raw_irqs_disabled_flags(flags))
- trace_hardirqs_off();
+ __trace_hardirqs_off();
else
- trace_hardirqs_on();
+ __trace_hardirqs_on();
}
static inline void trace_hardirqs_fixup(void)
Index: linux-compile.git/include/asm-x86/irqflags_64.h
===================================================================
--- linux-compile.git.orig/include/asm-x86/irqflags_64.h 2007-11-12 09:25:50.000000000 -0500
+++ linux-compile.git/include/asm-x86/irqflags_64.h 2008-01-09 17:07:15.000000000 -0500
@@ -120,9 +120,9 @@ static inline int raw_irqs_disabled(void
static inline void trace_hardirqs_fixup_flags(unsigned long flags)
{
if (raw_irqs_disabled_flags(flags))
- trace_hardirqs_off();
+ __trace_hardirqs_off();
else
- trace_hardirqs_on();
+ __trace_hardirqs_on();
}
static inline void trace_hardirqs_fixup(void)
--
On Wed, 2008-01-09 at 18:29 -0500, Steven Rostedt wrote:
> + /* Don't trace irqs off for idle */
> + stop_critical_timings();
> idle();
> + start_critical_timings();
Is there another way to hook into the idle routine? Right above these
lines there is a call to "enter_idle()" which I'm wondering about ..
Would be nice to have some sort of generic hook or method for this ..
Daniel
On Wed, 9 Jan 2008, Daniel Walker wrote:
>
> On Wed, 2008-01-09 at 18:29 -0500, Steven Rostedt wrote:
> > + /* Don't trace irqs off for idle */
> > + stop_critical_timings();
> > idle();
> > + start_critical_timings();
>
>
> Is there another way to hook into the idle routine? Right above these
> lines there is a call to "enter_idle()" which I'm wondering about ..
> Would be nice to have some sort of generic hook or method for this ..
enter_idle isn't generic.
-- Steve