Steven Rostedt (Red Hat)
cb86e05390
tracing: Have preempt(irqs)off trace preempt disabled functions
...
Joel Fernandes reported that the function tracing of preempt disabled
sections was not being reported when running either the preemptirqsoff or
preemptoff tracers. This was due to the fact that the function tracer
callback for those tracers checked if irqs were disabled before tracing. But
this fails when we want to trace preempt off locations as well.
Joel explained that he wanted to see funcitons where interrupts are enabled
but preemption was disabled. The expected output he wanted:
<...>-2265 1d.h1 3419us : preempt_count_sub <-irq_exit
<...>-2265 1d..1 3419us : __do_softirq <-irq_exit
<...>-2265 1d..1 3419us : msecs_to_jiffies <-__do_softirq
<...>-2265 1d..1 3420us : irqtime_account_irq <-__do_softirq
<...>-2265 1d..1 3420us : __local_bh_disable_ip <-__do_softirq
<...>-2265 1..s1 3421us : run_timer_softirq <-__do_softirq
<...>-2265 1..s1 3421us : hrtimer_run_pending <-run_timer_softirq
<...>-2265 1..s1 3421us : _raw_spin_lock_irq <-run_timer_softirq
<...>-2265 1d.s1 3422us : preempt_count_add <-_raw_spin_lock_irq
<...>-2265 1d.s2 3422us : _raw_spin_unlock_irq <-run_timer_softirq
<...>-2265 1..s2 3422us : preempt_count_sub <-_raw_spin_unlock_irq
<...>-2265 1..s1 3423us : rcu_bh_qs <-__do_softirq
<...>-2265 1d.s1 3423us : irqtime_account_irq <-__do_softirq
<...>-2265 1d.s1 3423us : __local_bh_enable <-__do_softirq
There's a comment saying that the irq disabled check is because there's a
possible race that tracing_cpu may be set when the function is executed. But
I don't remember that race. For now, I added a check for preemption being
enabled too to not record the function, as there would be no race if that
was the case. I need to re-investigate this, as I'm now thinking that the
tracing_cpu will always be correct. But no harm in keeping the check for
now, except for the slight performance hit.
Link: http://lkml.kernel.org/r/1457770386-88717-1-git-send-email-agnel.joel@gmail.com
Fixes: 5e6d2b9cfa "tracing: Use one prologue for the preempt irqs off tracer function tracers"
Cc: stable@vget.kernel.org # 2.6.37+
Reported-by: Joel Fernandes <agnel.joel@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 12:47:38 -04:00
..
bpf
bpf: fix branch offset adjustment on backjumps after patching ctx expansion
2016-02-10 16:56:47 -05:00
configs
debug
module: use a structure to encapsulate layout.
2015-12-04 22:46:25 +01:00
events
perf: Robustify task_function_call()
2016-02-25 08:44:29 +01:00
gcov
gcov: use within_module() helper.
2015-12-04 22:46:25 +01:00
irq
Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-01-31 14:48:58 -08:00
livepatch
livepatch: Cleanup module page permission changes
2015-12-04 22:51:07 +01:00
locking
Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-02-14 12:02:05 -08:00
power
PM: APM_EMULATION does not depend on PM
2016-01-27 23:20:14 +01:00
printk
kernel: printk: specify alignment for struct printk_log
2016-01-20 17:09:18 -08:00
rcu
Merge branches 'doc.2015.12.05a', 'exp.2015.12.07a', 'fixes.2015.12.07a', 'list.2015.12.04b' and 'torture.2015.12.05a' into HEAD
2015-12-07 17:02:54 -08:00
sched
sched/deadline: Fix trivial typo in printk() message
2016-02-17 10:02:00 +01:00
time
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-01-31 15:49:06 -08:00
trace
tracing: Have preempt(irqs)off trace preempt disabled functions
2016-03-18 12:47:38 -04:00
.gitignore
certs: add .gitignore to stop git nagging about x509_certificate_list
2015-10-21 15:18:35 +01:00
acct.c
async.c
async: export current_is_async()
2015-11-19 17:51:48 +01:00
audit.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2016-01-17 19:13:15 -08:00
audit.h
security: Make inode argument of inode_getsecid non-const
2015-12-24 11:09:39 -05:00
audit_fsnotify.c
wrappers for ->i_mutex access
2016-01-22 18:04:28 -05:00
audit_tree.c
audit: audit_tree_match can be boolean
2015-11-04 08:23:51 -05:00
audit_watch.c
wrappers for ->i_mutex access
2016-01-22 18:04:28 -05:00
auditfilter.c
audit: fix comment block whitespace
2015-11-04 08:23:51 -05:00
auditsc.c
security: Make inode argument of inode_getsecid non-const
2015-12-24 11:09:39 -05:00
backtracetest.c
bounds.c
capability.c
cgroup.c
cgroup: make sure a parent css isn't freed before its children
2016-01-22 10:42:58 -05:00
cgroup_freezer.c
cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends
2015-12-03 10:24:08 -05:00
cgroup_pids.c
cgroup_pids: fix a typo.
2015-12-14 14:54:37 -05:00
compat.c
configs.c
context_tracking.c
context_tracking: Switch to new static_branch API
2015-11-24 09:56:43 +01:00
cpu.c
kernel/cpu.c: make set_cpu_* static inlines
2016-01-20 17:09:18 -08:00
cpu_pm.c
kernel/cpu_pm: fix cpu_cluster_pm_exit comment
2015-09-03 02:42:20 +02:00
cpuset.c
cpuset: make mm migration asynchronous
2016-01-22 10:22:46 -05:00
crash_dump.c
cred.c
kmemcg: account certain kmem allocations to memcg
2016-01-14 16:00:49 -08:00
delayacct.c
kmemcg: account certain kmem allocations to memcg
2016-01-14 16:00:49 -08:00
dma.c
elfcore.c
exec_domain.c
exit.c
exit: remove unneeded declaration of exit_mm()
2016-01-20 17:09:18 -08:00
extable.c
kernel/extable.c: remove duplicated include
2015-09-10 13:29:01 -07:00
fork.c
mm: rework virtual memory accounting
2016-01-14 16:00:49 -08:00
freezer.c
futex.c
rtmutex: Make wait_lock irq safe
2016-01-26 11:08:35 +01:00
futex_compat.c
ptrace: use fsuid, fsgid, effective creds for fs access checks
2016-01-20 17:09:18 -08:00
groups.c
hung_task.c
irq_work.c
treewide: Remove old email address
2015-11-23 09:44:58 +01:00
jump_label.c
treewide: Remove old email address
2015-11-23 09:44:58 +01:00
kallsyms.c
kcmp.c
ptrace: use fsuid, fsgid, effective creds for fs access checks
2016-01-20 17:09:18 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c
kexec: set KEXEC_TYPE_CRASH before sanity_check_segment_list()
2016-01-20 17:09:18 -08:00
kexec_core.c
kernel/kexec_core.c: use list_for_each_entry_safe in kimage_free_page_list
2016-01-20 17:09:18 -08:00
kexec_file.c
kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE
2016-01-20 17:09:18 -08:00
kexec_internal.h
kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE
2016-01-20 17:09:18 -08:00
kmod.c
kmod: don't run async usermode helper as a child of kworker thread
2015-10-23 17:55:10 +09:00
kprobes.c
perf/x86/hw_breakpoints: Disallow kernel breakpoints unless kprobe-safe
2015-08-04 10:16:54 +02:00
ksysfs.c
rcu: Remove TINY_RCU bloat from pointless boot parameters
2015-12-07 16:59:37 -08:00
kthread.c
kernel/kthread.c:kthread_create_on_node(): clarify documentation
2015-09-04 16:54:41 -07:00
latencytop.c
Makefile
sys_membarrier(): system-wide memory barrier (generic, x86)
2015-09-11 15:21:34 -07:00
membarrier.c
sys_membarrier(): system-wide memory barrier (generic, x86)
2015-09-11 15:21:34 -07:00
memremap.c
Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
2016-02-25 18:54:53 -08:00
module-internal.h
module.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
2016-02-18 16:34:15 -08:00
module_signing.c
KEYS: Merge the type-specific data with the payload data
2015-10-21 15:18:36 +01:00
notifier.c
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-09-01 08:40:25 -07:00
nsproxy.c
padata.c
panic.c
printk: do cond_resched() between lines while outputting to consoles
2016-01-16 11:17:25 -08:00
params.c
Nothing exciting, minor tweaks and cleanups.
2015-11-09 15:53:39 -08:00
pid.c
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-01-31 15:44:04 -08:00
pid_namespace.c
profile.c
mm: rename alloc_pages_exact_node() to __alloc_pages_node()
2015-09-08 15:35:28 -07:00
ptrace.c
ptrace: use fsuid, fsgid, effective creds for fs access checks
2016-01-20 17:09:18 -08:00
range.c
reboot.c
kexec: split kexec_load syscall from kexec core code
2015-09-10 13:29:01 -07:00
relay.c
wrappers for ->i_mutex access
2016-01-22 18:04:28 -05:00
resource.c
kernel/resource.c: fix muxed resource handling in __request_region()
2016-02-20 08:57:52 -08:00
seccomp.c
seccomp: always propagate NO_NEW_PRIVS on tsync
2016-01-27 07:38:25 -08:00
signal.c
signals: avoid random wakeups in sigsuspend()
2016-02-05 18:10:40 -08:00
smp.c
mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
2015-11-06 17:50:42 -08:00
smpboot.c
stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark()
2015-10-20 10:23:55 +02:00
smpboot.h
softirq.c
stacktrace.c
stop_machine.c
kernel/stop_machine.c: remove CONFIG_SMP dependencies
2016-01-16 11:17:24 -08:00
sys.c
prctl: take mmap sem for writing to protect against others
2016-01-20 17:09:18 -08:00
sys_ni.c
vfs: add copy_file_range syscall and vfs helper
2015-12-01 14:00:53 -05:00
sysctl.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2016-01-22 10:24:03 -08:00
sysctl_binary.c
task_work.c
task_work: remove fifo ordering guarantee
2015-09-05 13:46:58 -07:00
taskstats.c
test_kprobes.c
torture.c
torture: Consolidate cond_resched_rcu_qs() into stutter_wait()
2015-10-06 11:25:01 -07:00
tracepoint.c
tracepoint: Give priority to probes of tracepoints
2015-10-25 21:33:54 -04:00
tsacct.c
uid16.c
up.c
user-return-notifier.c
user.c
user_namespace.c
kernel/*: switch to memdup_user_nul()
2016-01-04 10:27:55 -05:00
utsname.c
utsname_sysctl.c
watchdog.c
Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2016-01-11 18:53:13 -08:00
workqueue.c
workqueue: handle NUMA_NO_NODE for unbound pool_workqueue lookup
2016-02-10 12:13:05 -05:00
workqueue_internal.h