linux/kernel/trace
Soumya PN 6112a300c9 ftrace: Don't disable irqs when taking the tasklist_lock read_lock
In ftrace.c inside the function alloc_retstack_tasklist() (which will be
invoked when function_graph tracing is on) the tasklist_lock is being
held as reader while iterating through a list of threads. Here the lock
is being held as reader with irqs disabled. The tasklist_lock is never
write_locked in interrupt context so it is safe to not disable interrupts
for the duration of read_lock in this block which, can be significant,
given the block of code iterates through all threads. Hence changing the
code to call read_lock() and read_unlock() instead of read_lock_irqsave()
and read_unlock_irqrestore().

A similar change was made in commits: 8063e41d2f ("tracing: Change
syscall_*regfunc() to check PF_KTHREAD and use for_each_process_thread()")'
and 3472eaa1f1 ("sched: normalize_rt_tasks(): Don't use _irqsave for
tasklist_lock, use task_rq_lock()")'

Link: http://lkml.kernel.org/r/1463500874-77480-1-git-send-email-soumya.p.n@hpe.com

Signed-off-by: Soumya PN <soumya.p.n@hpe.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-20 13:19:37 -04:00
..
blktrace.c kernel/...: convert pr_warning to pr_warn 2016-03-22 15:36:02 -07:00
bpf_trace.c bpf: prevent kprobe+bpf deadlocks 2016-03-08 15:28:30 -05:00
ftrace.c ftrace: Don't disable irqs when taking the tasklist_lock read_lock 2016-05-20 13:19:37 -04:00
Kconfig tracing: Add 'hist' event trigger command 2016-04-19 12:16:14 -04:00
Makefile tracing: Add 'hist' event trigger command 2016-04-19 12:16:14 -04:00
power-traces.c cpufreq: powernv/tracing: Add powernv_throttle tracepoint 2016-02-05 02:38:02 +01:00
ring_buffer_benchmark.c ring_buffer: Remove unneeded smp_wmb() before wakeup of reader benchmark 2015-11-03 16:19:02 -05:00
ring_buffer.c ring-buffer: Process commits whenever moving to a new page. 2015-11-25 15:24:05 -05:00
rpm-traces.c
trace_benchmark.c tracing: Only benchmark the time tracepoints take if tracing is on 2015-11-02 13:34:58 -05:00
trace_benchmark.h tracing: Add tracepoint benchmark tracepoint 2014-05-29 22:49:54 -04:00
trace_branch.c tracing: Remove {start,stop}_branch_trace 2015-10-21 10:10:09 -04:00
trace_clock.c tracing: Export tracing clock functions 2015-05-12 15:56:57 -04:00
trace_entries.h tracing: %pF is only for function pointers 2015-03-25 08:57:22 -04:00
trace_event_perf.c Not much new with tracing for this release. Mostly just clean ups and 2016-01-12 20:04:15 -08:00
trace_events_filter_test.h
trace_events_filter.c tracing: Use temp buffer when filtering events 2016-05-03 17:59:24 -04:00
trace_events_hist.c tracing: Add check for NULL event field when creating hist field 2016-04-26 09:40:29 -04:00
trace_events_trigger.c tracing: Add support for named triggers 2016-04-19 18:56:00 -04:00
trace_events.c tracing: Use temp buffer when filtering events 2016-05-03 17:59:24 -04:00
trace_export.c tracing: ftrace_event_is_function() can return boolean 2015-11-02 14:28:05 -05:00
trace_functions_graph.c arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections 2016-03-25 16:37:42 -07:00
trace_functions.c tracing: Make tracer_flags use the right set_flag callback 2016-03-08 11:19:08 -05:00
trace_irqsoff.c tracing: Remove redundant reset per-CPU buff in irqsoff tracer 2016-03-18 16:39:11 -04:00
trace_kdb.c tracing: Move trace_flags from global to a trace_array field 2015-09-30 15:22:55 -04:00
trace_kprobe.c kernel/...: convert pr_warning to pr_warn 2016-03-22 15:36:02 -07:00
trace_mmiotrace.c kernel/...: convert pr_warning to pr_warn 2016-03-22 15:36:02 -07:00
trace_nop.c tracing: Fix typoes in code comment and printk in trace_nop.c 2016-03-08 11:23:57 -05:00
trace_output.c tracing: Record and show NMI state 2016-03-22 18:04:10 -04:00
trace_output.h tracing: Turn seq_print_user_ip() into a static function 2015-09-28 10:16:12 -04:00
trace_printk.c tracing: Fix trace_printk() to print when not using bprintk() 2016-03-22 18:02:40 -04:00
trace_probe.c kernel/...: convert pr_warning to pr_warn 2016-03-22 15:36:02 -07:00
trace_probe.h kernel/trace_probe: is_good_name can be boolean 2015-09-22 13:11:30 -04:00
trace_sched_switch.c sched/core: Fix trace_sched_switch() 2015-10-06 17:08:15 +02:00
trace_sched_wakeup.c Most of the changes are clean ups and small fixes. Some of them have 2015-11-06 13:30:20 -08:00
trace_selftest_dynamic.c
trace_selftest.c Seems that Peter Zijlstra added a new check that is making old 2014-10-12 07:28:55 -04:00
trace_seq.c tracing: use %*pb[l] to print bitmaps including cpumasks and nodemasks 2015-02-13 21:21:37 -08:00
trace_stack.c tracing, kasan: Silence Kasan warning in check_stack of stack_tracer 2016-02-19 12:36:44 -05:00
trace_stat.c kernel/...: convert pr_warning to pr_warn 2016-03-22 15:36:02 -07:00
trace_stat.h
trace_syscalls.c Nothing major this round. Mostly small clean ups and fixes. 2016-03-24 10:52:25 -07:00
trace_uprobe.c kernel/...: convert pr_warning to pr_warn 2016-03-22 15:36:02 -07:00
trace.c tracing: Use temp buffer when filtering events 2016-05-03 17:59:24 -04:00
trace.h tracing: Use temp buffer when filtering events 2016-05-03 17:59:24 -04:00
tracing_map.c tracing: Handle tracing_map_alloc_elts() error path correctly 2016-04-26 09:40:30 -04:00
tracing_map.h tracing: Update some tracing_map constants and comments 2016-04-19 12:16:06 -04:00