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Author SHA1 Message Date
Ingo Molnar
26198c21d1 Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core
Pull ftrace updates from Steve Rostedt:

" This patch series extends ftrace function tracing utility to be
  more dynamic for its users. It allows for data passing to the callback
  functions, as well as reading regs as if a breakpoint were to trigger
  at function entry.

  The main goal of this patch series was to allow kprobes to use ftrace
  as an optimized probe point when a probe is placed on an ftrace nop.
  With lots of help from Masami Hiramatsu, and going through lots of
  iterations, we finally came up with a good solution. "

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-21 11:23:40 +02:00
Masami Hiramatsu
e525389651 kprobes/x86: ftrace based optimization for x86
Add function tracer based kprobe optimization support
handlers on x86. This allows kprobes to use function
tracer for probing on mcount call.

Link: http://lkml.kernel.org/r/20120605102838.27845.26317.stgit@localhost.localdomain

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

[ Updated to new port of ftrace save regs functions ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:59 -04:00
Masami Hiramatsu
ae6aa16fdc kprobes: introduce ftrace based optimization
Introduce function trace based kprobes optimization.

With using ftrace optimization, kprobes on the mcount calling
address, use ftrace's mcount call instead of breakpoint.
Furthermore, this optimization works with preemptive kernel
not like as current jump-based optimization. Of cource,
this feature works only if the probe is on mcount call.

Only if kprobe.break_handler is set, that probe is not
optimized with ftrace (nor put on ftrace). The reason why this
limitation comes is that this break_handler may be used only
from jprobes which changes ip address (for fetching the function
arguments), but function tracer ignores modified ip address.

Changes in v2:
 - Fix ftrace_ops registering right after setting its filter.
 - Unregister ftrace_ops if there is no kprobe using.
 - Remove notrace dependency from __kprobes macro.

Link: http://lkml.kernel.org/r/20120605102832.27845.63461.stgit@localhost.localdomain

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:58 -04:00
Steven Rostedt
4dc936769e ftrace: Make ftrace_location() a nop on !DYNAMIC_FTRACE
When CONFIG_DYNAMIC_FTRACE is not set, ftrace_location() is not defined.
If a user (like kprobes) references this function, it will break
the compile when CONFIG_DYNAMIC_FTRACE is not set.

Add ftrace_location() as a nop (return 0) when DYNAMIC_FTRACE
is not defined.

Link: http://lkml.kernel.org/r/20120612225426.961092717@goodmis.org

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:57 -04:00
Masami Hiramatsu
25764288d8 kprobes: Move locks into appropriate functions
Break a big critical region into fine-grained pieces at
registering kprobe path. This helps us to solve circular
locking dependency when introducing ftrace-based kprobes.

Link: http://lkml.kernel.org/r/20120605102826.27845.81689.stgit@localhost.localdomain

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:57 -04:00
Masami Hiramatsu
f7fa6ef0de kprobes: cleanup to separate probe-able check
Separate probe-able address checking code from
register_kprobe().

Link: http://lkml.kernel.org/r/20120605102820.27845.90133.stgit@localhost.localdomain

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:56 -04:00
Steven Rostedt
72ef3794c5 kprobes: Inverse taking of module_mutex with kprobe_mutex
Currently module_mutex is taken before kprobe_mutex, but this
can cause issues when we have kprobes register ftrace, as the ftrace
mutex is taken before enabling a tracepoint, which currently takes
the module mutex.

If module_mutex is taken before kprobe_mutex, then we can not
have kprobes use the ftrace infrastructure.

There seems to be no reason that the kprobe_mutex can't be taken
before the module_mutex. Running lockdep shows that it is safe
among the kernels I've run.

Link: http://lkml.kernel.org/r/20120605102814.27845.21047.stgit@localhost.localdomain

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:55 -04:00
Masami Hiramatsu
647664eaf4 ftrace: add ftrace_set_filter_ip() for address based filter
Add a new filter update interface ftrace_set_filter_ip()
to set ftrace filter by ip address, not only glob pattern.

Link: http://lkml.kernel.org/r/20120605102808.27845.67952.stgit@localhost.localdomain

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:55 -04:00
Steven Rostedt
ad97772ad8 ftrace: Add selftest to test function save-regs support
Add selftests to test the save-regs functionality of ftrace.

If the arch supports saving regs, then it will make sure that regs is
at least not NULL in the callback.

If the arch does not support saving regs, it makes sure that the
registering of the ftrace_ops that requests saving regs fails.
It then tests the registering of the ftrace_ops succeeds if the
'IF_SUPPORTED' flag is set. Then it makes sure that the regs passed to
the function is NULL.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:54 -04:00
Steven Rostedt
ea701f11da ftrace: Add selftest to test function trace recursion protection
Add selftests to test the function tracing recursion protection actually
does work. It also tests if a ftrace_ops states it will perform its own
protection. Although, even if the ftrace_ops states it will protect itself,
the ftrace infrastructure may still provide protection if the arch does
not support all features or another ftrace_ops is registered.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:54 -04:00
Steven Rostedt
47239c4d8d ftrace: Only compile ftrace selftest if selftests are enabled
No need to compile in the ftrace selftest helper file if selftests are
not being executed.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:53 -04:00
Steven Rostedt
4740974a68 ftrace: Add default recursion protection for function tracing
As more users of the function tracer utility are being added, they do
not always add the necessary recursion protection. To protect from
function recursion due to tracing, if the callback ftrace_ops does not
specifically specify that it protects against recursion (by setting
the FTRACE_OPS_FL_RECURSION_SAFE flag), the list operation will be
called by the mcount trampoline which adds recursion protection.

If the flag is set, then the function will be called directly with no
extra protection.

Note, the list operation is called if more than one function callback
is registered, or if the arch does not support all of the function
tracer features.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:52 -04:00
Steven Rostedt
5767cfeaa9 ftrace/x86: Remove function_trace_stop check from graph caller
The graph caller is called by the mcount callers, which already does
the check against the function_trace_stop variable. No reason to
check it again.

Link: http://lkml.kernel.org/r/20120711195745.588538769@goodmis.org

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:51 -04:00
Uros Bizjak
e4ea3f6b1b ftrace/x86_32: Simplify parameter setup for ftrace_regs_caller
The final position of the stack after saving regs and setting up
the parameters for ftrace_regs_call, is the position of the pt_regs
needed for the 4th parameter. Instead of saving it into a temporary
reg and pushing the reg, simply push the stack pointer.

Link: http://lkml.kernel.org/r/1342702344.12353.16.camel@gandalf.stny.rr.com

Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31 10:29:34 -04:00
Oleg Nesterov
194f8dcbe9 uprobes: __replace_page() needs munlock_vma_page()
Like do_wp_page(), __replace_page() should do munlock_vma_page()
for the case when the old page still has other !VM_LOCKED
mappings. Unfortunately this needs mm/internal.h.

Also, move put_page() outside of ptl lock. This doesn't really
matter but looks a bit better.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182249.GA20372@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:25 +02:00
Oleg Nesterov
57683f72b8 uprobes: Rename vma_address() and make it return "unsigned long"
1. vma_address() returns loff_t, this looks confusing and this
   is unnecessary after the previous change. Make it return "ulong",
   all callers truncate the result anyway.

2. Its name conflicts with mm/rmap.c:vma_address(), rename it to
   offset_to_vaddr(), this matches vaddr_to_offset().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182247.GA20365@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:25 +02:00
Oleg Nesterov
f4d6dfe551 uprobes: Fix register_for_each_vma()->vma_address() check
1. register_for_each_vma() checks that vma_address() == vaddr,
   but this is not enough. We should also ensure that
   vaddr >= vm_start, find_vma() guarantees "vaddr < vm_end" only.

2. After the prevous changes, register_for_each_vma() is the
   only reason why vma_address() has to return loff_t, all other
   users know that we have the valid mapping at this offset and
   thus the overflow is not possible.

   Change the code to use vaddr_to_offset() instead, imho this looks
   more clean/understandable and now we can change vma_address().

3. While at it, remove the unnecessary type-cast.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182244.GA20362@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:24 +02:00
Oleg Nesterov
cb113b47d0 uprobes: Introduce vaddr_to_offset(vma, vaddr)
Add the new helper, vaddr_to_offset(vma, vaddr) which returns
the offset in vma->vm_file this vaddr is mapped at.

Change build_probe_list() and find_active_uprobe() to use the
new helper, the next patch adds another user.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182242.GA20355@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:24 +02:00
Oleg Nesterov
891c397081 uprobes: Teach build_probe_list() to consider the range
Currently build_probe_list() builds the list of all uprobes
attached to the given inode, and the caller should filter out
those who don't fall into the [start,end) range, this is
sub-optimal.

This patch turns find_least_offset_node() into
find_node_in_range() which returns the first node inside the
[min,max] range, and changes build_probe_list() to use this node
as a starting point for rb_prev() and rb_next() to find all
other nodes the caller needs. The resulting list is no longer
sorted but we do not care.

This can speed up both build_probe_list() and the callers, but
there is another reason to introduce find_node_in_range(). It
can be used to figure out whether the given vma has uprobes or
not, this will be needed soon.

While at it, shift INIT_LIST_HEAD(tmp_list) into
build_probe_list().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182240.GA20352@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:23 +02:00
Oleg Nesterov
89133786f9 uprobes: Remove insert_vm_struct()->uprobe_mmap()
Remove insert_vm_struct()->uprobe_mmap(). It is not needed, nobody
except arch/ia64/kernel/perfmon.c uses insert_vm_struct(vma)
with vma->vm_file != NULL.

And it is wrong. Again, get_user_pages() can not succeed before
vma_link(vma) makes is visible to find_vma(). And even if this
worked, we must not insert the new bp before this mapping is
visible to vma_prio_tree_foreach() for uprobe_unregister().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182238.GA20349@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:22 +02:00
Oleg Nesterov
6dab3cc078 uprobes: Remove copy_vma()->uprobe_mmap()
Remove copy_vma()->uprobe_mmap(new_vma), it is absolutely wrong.

This new_vma was just initialized to represent the new unmapped
area, [vm_start, vm_end) was returned by get_unmapped_area() in
the caller.

This means that uprobe_mmap()->get_user_pages() will fail for
sure, simply because find_vma() can never succeed. And I
verified that sys_mremap()->mremap_to() indeed always fails with
the wrong ENOMEM code if [addr, addr+old_len] is probed.

And why this uprobe_mmap() was added? I believe the intent was
wrong. Note that the caller is going to do move_page_tables(),
all registered uprobes are already faulted in, we only change
the virtual addresses.

NOTE: However, somehow we need to close the race with
uprobe_register() which relies on map_info->vaddr. This needs
another fix I'll try to do later. Probably we need uprobe_mmap()
in move_vma() but we can not do this right now, this can confuse
uprobes_state.counter (which I still hope we are going to kill).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182236.GA20342@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:22 +02:00
Oleg Nesterov
aefd8933d4 uprobes: Fix overflow in vma_address()/find_active_uprobe()
vma->vm_pgoff is "unsigned long", it should be promoted to
loff_t before the multiplication to avoid the overflow.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182233.GA20339@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:21 +02:00
Oleg Nesterov
2fd611a991 uprobes: Suppress uprobe_munmap() from mmput()
uprobe_munmap() does get_user_pages() and it is also called from
the final mmput()->exit_mmap() path. This slows down
exit/mmput() for no reason, and I think  it is simply
dangerous/wrong to try to fault-in a page into the dying mm. If
nothing else, this happens after the last sync_mm_rss(), afaics
handle_mm_fault() can change the task->rss_stat and make the
subsequent check_mm() unhappy.

Change uprobe_munmap() to check mm->mm_users != 0.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182231.GA20336@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:21 +02:00
Oleg Nesterov
665605a2a2 uprobes: Uprobe_mmap/munmap needs list_for_each_entry_safe()
The bug was introduced by me in 449d0d7c ("uprobes: Simplify the
usage of uprobe->pending_list").

Yes, we do not care about uprobe->pending_list after return and
nobody can remove the current list entry, but put_uprobe(uprobe)
can actually free it and thus we need list_for_each_safe().

Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Link: http://lkml.kernel.org/r/20120729182229.GA20329@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:20 +02:00
Oleg Nesterov
9f92448cee uprobes: Clean up and document write_opcode()->lock_page(old_page)
The comment above write_opcode()->lock_page(old_page) tells
about the race with do_wp_page(). I don't really understand
which exactly race it means, but afaics this lock_page() was not
enough to close all races with do_wp_page().

Anyway, since:

   77fc4af1b5 uprobes: Change register_for_each_vma() to take mm->mmap_sem for writing

this code is always called with ->mmap_sem held for writing,
so we can forget about do_wp_page().

However, we can't simply remove this lock_page(), and the only
(afaics) reason is __replace_page()->try_to_free_swap().

Nothing in write_opcode() needs it, move it into
__replace_page() and fix the comment.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182220.GA20322@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:20 +02:00
Oleg Nesterov
089ba999dc uprobes: Kill write_opcode()->lock_page(new_page)
write_opcode() does lock_page(new_page) for no reason. Nobody
can see this page until __replace_page() exposes it under ptl
lock, and we do nothing with this page after pte_unmap_unlock().

If nothing else, the similar code in do_wp_page() doesn't lock
the new page for page_add_new_anon_rmap/set_pte_at_notify.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182218.GA20315@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:19 +02:00
Oleg Nesterov
c517ee744b uprobes: __replace_page() should not use page_address_in_vma()
page_address_in_vma(old_page) in __replace_page() is ugly and
wrong. The caller already knows the correct virtual address,
this page was found by get_user_pages(vaddr).

However, page_address_in_vma() can actually fail if
page->mapping was cleared by __delete_from_page_cache() after
get_user_pages() returns. But this means the race with page
reclaim, write_opcode() should not fail, it should retry and
read this page again. Probably the race with remove_mapping() is
not possible due to page_freeze_refs() logic, but afaics at
least shmem_writepage()->shmem_delete_from_page_cache() can
clear ->mapping.

We could change __replace_page() to return -EAGAIN in this case,
but it would be better to simply use the caller's vaddr and rely
on page_check_address().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182216.GA20311@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:19 +02:00
Oleg Nesterov
f403072c61 uprobes: Don't recheck vma/f_mapping in write_opcode()
write_opcode() rechecks valid_vma() and ->f_mapping, this is
pointless. The caller, register_for_each_vma() or uprobe_mmap(),
has already done these checks under mmap_sem.

To clarify, uprobe_mmap() checks valid_vma() only, but we can
rely on build_probe_list(vm_file->f_mapping->host).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182212.GA20304@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-30 11:27:18 +02:00
Jovi Zhang
35d56ca9d4 perf/x86: Fix missing struct before structure name
When CONFIG_PERF_EVENTS disabled, there will have a compiliation
error, because missing struct before structure name.

Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jiri Kosina <trivial@kernel.org>
Link: http://lkml.kernel.org/r/CACV3sbKF%3DCX%2B2jWEWesfCA6rBoQ3wDM4-5ac9MuBtVbCtMRHdQ@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-26 15:04:34 +02:00
Yan, Zheng
c1ece48cf7 perf/x86: Fix format definition of SNB-EP uncore QPI box
The event control register of SNB-EP uncore QPI box has a one bit
extension at bit position 21.

Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1343097850-4348-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-26 12:23:14 +02:00
Peter Zijlstra
597ed953d7 perf/x86: Make bitfield unsigned
Fix:

 arch/x86/kernel/cpu/perf_event.h:377:43: sparse: dubious one-bit signed bitfield

Cc: Borislav Petkov <bp@amd64.org>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-2jxkmktkppkclj1qe6qxd7ah@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-26 12:23:13 +02:00
Yan, Zheng
74e6543fdc perf/x86: Fix LLC-* and node-* events on Intel SandyBridge
LLC-* and node-* events require using the OFFCORE_RESPONSE events
on SandyBridge, but the hw_cache_extra_regs is left uninitialized.
This patch adds the missing extra register configure table for
SandyBridge.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342517275-2875-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-26 12:23:12 +02:00
Yan, Zheng
254298c726 perf/x86: Add Intel Nehalem-EX uncore support
The uncore subsystem in Nehalem-EX consists of 7 components
(U-Box, C-Box, B-Box, S-Box, R-Box, M-Box and W-Box). This
patch is large because the way to program these boxes is
diverse.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4FF534F1.3030307@intel.com
[ Improved the code. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-26 12:23:11 +02:00
Yan, Zheng
4f3f713fc7 perf/x86: Fix typo in format definition of uncore PCU filter
The format definition of uncore PCU filter should be filter_band*
instead of filter_brand*.

Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1343024611-4692-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-26 12:23:11 +02:00
Andrew Vagin
895dd92c03 sched: Deliver sched_switch events to the current task
Otherwise they can't be filtered for a defined task:

  perf record -e sched:sched_switch ./foo

This command doesn't report any events without this patch.

I think it isn't a security concern if someone knows who will
be executed next - this can already be observed by polling /proc
state. By default perf is disabled for non-root users in any case.

I need these events for profiling sleep times.  sched_switch is used for
getting callchains and sched_stat_* is used for getting time periods.
These events are combined in user space, then it can be analyzed by
perf tools.

Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arun Sharma <asharma@fb.com>
Link: http://lkml.kernel.org/r/1342088069-1005148-1-git-send-email-avagin@openvz.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-26 12:23:10 +02:00
Ingo Molnar
045e7e6047 perf/core fixes and improvements:
. libtraceevent build fixes from Namhyung Kim
 
 . Prevent overflow when calculating annotation buckets size, from Cody Schafer
 
 . Set breakpoint events sample period to 1, just like trace events, from Jovi Zhang
 
 . Fix strerror_r usage, from Kirill Shutemov
 
 . Fix duplicate function declaration problems with bison 2.6, from Kirill Shutemov
 
 . Add DSO caching facility (and perf test entry) to speed up binary file
   reading, will be used by the DWARF unwind code, from Jiri Olsa
 
 . Fix trace event storms by setting PERF_SAMPLE_PERIOD, from Frederic Weisbecker
 
 . perf kvm fixes from David Ahern
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core fixes and improvements from Arnaldo Carvalho de Melo:

 * libtraceevent build fixes from Namhyung Kim

 * Prevent overflow when calculating annotation buckets size, from Cody Schafer

 * Set breakpoint events sample period to 1, just like trace events, from Jovi Zhang

 * Fix strerror_r usage, from Kirill Shutemov

 * Fix duplicate function declaration problems with bison 2.6, from Kirill Shutemov

 * Add DSO caching facility (and perf test entry) to speed up binary file
   reading, will be used by the DWARF unwind code, from Jiri Olsa

 * Fix trace event storms by setting PERF_SAMPLE_PERIOD, from Frederic Weisbecker

 * perf kvm fixes from David Ahern

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-25 20:52:59 +02:00
Cody Schafer
8696329b7b perf annotate: Prevent overflow in size calculation
A large enough symbol size causes an overflow in the size parameter to
the histogram allocation, leading to a segfault in
symbol__inc_addr_samples later on when this histogram is accessed.

In the case of being called via perf-report, this returns back and
gracefully ignores the sample, eventually ignoring the chained return
value of perf_session_deliver_event in flush_sample_queue.

Signed-off-by: Cody Schafer <cody@linux.vnet.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1342753525-4521-1-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 13:06:42 -03:00
Namhyung Kim
52f18a2ff9 tools lib traceevent: Ignore TRACEEVENT-CFLAGS file
The TRACEEVENT-CFLAGS file is used to detect any change on compiler
flags. Just ignore it.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1341559297-25725-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:54:44 -03:00
Namhyung Kim
52b5c0d485 tools lib traceevent: Detect build environment changes
Cross compiling perf requires setting ARCH and CROSS_COMPILE variables,
but libtraceevent couldn't detect the changes so it ends up believing no
recompiling is required. Thus the linker failed like:

     LINK perf
 ../lib/traceevent//libtraceevent.a: member ../lib/traceevent//libtraceevent.a(event-parse.o) in archive is not an object
 collect2: ld returned 1 exit status
 make: *** [perf] Error 1

This patch fixes this by adding TRACEEVENT-CFLAGS file like
PERF-CFLAGS to track those changes.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1341559297-25725-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:54:06 -03:00
Kirill A. Shutemov
043d1a5c14 perf tools: Fix build error with bison 2.6
Bison 2.6 started to generate parse_events_parse() declaration in header. In
this case we have redundant redeclaration:

util/parse-events.c:29:5: error: redundant redeclaration of ‘parse_events_parse’ [-Werror=redundant-decls]
In file included from util/parse-events.c:14:0:
util/parse-events-bison.h:99:5: note: previous declaration of ‘parse_events_parse’ was here
cc1: all warnings being treated as errors

Let's disable -Wredundant-decls for util/parse-events.c since it includes
header we can't control.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120723210407.GA25186@shutemov.name
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:49:19 -03:00
Kirill A. Shutemov
4cc49d4dc8 perf tools: use XSI-complaint version of strerror_r() instead of GNU-specific
Perf uses GNU-specific version of strerror_r(). The GNU-specific strerror_r()
returns a pointer to a string containing the error message.  This may be either
a pointer to a string that the function stores in buf, or a pointer to some
(immutable) static string (in which case buf is unused).

In glibc-2.16 GNU version was marked with attribute warn_unused_result.  It
triggers few warnings in perf:

util/target.c: In function ‘perf_target__strerror’:
util/target.c:114:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]
ui/browsers/hists.c: In function ‘hist_browser__dump’:
ui/browsers/hists.c:981:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]

They are bugs.

Let's fix strerror_r() usage.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Ulrich Drepper <drepper@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/20120723210654.GA25248@shutemov.name
[ committer note: s/assert/BUG_ON/g ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:46:04 -03:00
Jovi Zhang
4a841d650e perf tools: Make the breakpoint events sample period default to 1
There have one problem about hw_breakpoint perf event, as watched, the
events reported to userspace is not correctly, sometime one trigger
bp_event report several events, sometime bp_event cannot go through to
user.

The root cause is attr->freq is 1 passed to kernel defaultly in bp
events, this make kernel calculate event period not as expect, make
sample period to 1 will change attr->freq to 0, to fix this problem.

This patch is similar with commit f92128 about tracepoint events:
    perf: Make the trace events sample period default to 1

Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/CACV3sbLF8taiCq_VYW-sgRJyupeMzg58C7ZXfMe3xZUiH_Mx6w@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:37:46 -03:00
Jiri Olsa
f7add55653 perf test: Add dso data caching tests
Adding automated test for DSO data reading. Testing raw/cached reads
from different file/cache locations.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-18-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:33:17 -03:00
Jiri Olsa
4dff624ae0 perf symbols: Add dso data caching
Adding dso data caching so we don't need to open/read/close, each time
we want dso data.

The DSO data caching affects following functions:
  dso__data_read_offset
  dso__data_read_addr

Each DSO read tries to find the data (based on offset) inside the cache.
If it's not present it fills the cache from file, and returns the data.
If it is present, data are returned with no file read.

Each data read is cached by reading cache page sized/aligned amount of
DSO data. The cache page size is hardcoded to 4096.  The cache is using
RB tree with file offset as a sort key.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-17-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:33:04 -03:00
Jiri Olsa
949d160b69 perf symbols: Add interface to read DSO image data
Adding following interface for DSO object to allow
reading of DSO image data:

  dso__data_fd
    - opens DSO and returns file descriptor
      Binary types are used to locate/open DSO in following order:
        DSO_BINARY_TYPE__BUILD_ID_CACHE
        DSO_BINARY_TYPE__SYSTEM_PATH_DSO
      In other word we first try to open DSO build-id path,
      and if that fails we try to open DSO system path.

  dso__data_read_offset
    - reads DSO data from specified offset

  dso__data_read_addr
    - reads DSO data from specified address/map.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-11-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:32:49 -03:00
Jiri Olsa
44f24cb315 perf symbols: Factor DSO symtab types to generic binary types
Adding interface to access DSOs so it could be used
from another place.

New DSO binary type is added - making current SYMTAB__*
types more general:
   DSO_BINARY_TYPE__* = SYMTAB__*

Following function is added to return path based on the specified
binary type:
   dso__binary_type_file

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-10-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:32:36 -03:00
Frederic Weisbecker
6654f5d8bd perf hists: Print newline between hists callchains
Tiny cosmetic fix. The lack of a newline between hists callchains was
looking slightly messy.

Before:

     0.24%      swapper  [kernel.kallsyms]  [k] _raw_spin_lock_irq
                |
                --- _raw_spin_lock_irq
                    run_timer_softirq
                    __do_softirq
                    call_softirq
                    do_softirq
                    irq_exit
                    smp_apic_timer_interrupt
                    apic_timer_interrupt
                    default_idle
                    amd_e400_idle
                    cpu_idle
                    start_secondary
     0.10%         perf  [kernel.kallsyms]  [k] lock_is_held
                   |
                   --- lock_is_held
                       __might_sleep
                       mutex_lock_nested
                       perf_event_for_each_child
                       perf_ioctl
                       do_vfs_ioctl
                       sys_ioctl
                       system_call_fastpath
                       ioctl
                       cmd_record
                       run_builtin
                       main
                       __libc_start_main

After:

     0.24%      swapper  [kernel.kallsyms]  [k] _raw_spin_lock_irq
                |
                --- _raw_spin_lock_irq
                    run_timer_softirq
                    __do_softirq
                    call_softirq
                    do_softirq
                    irq_exit
                    smp_apic_timer_interrupt
                    apic_timer_interrupt
                    default_idle
                    amd_e400_idle
                    cpu_idle
                    start_secondary

     0.10%         perf  [kernel.kallsyms]  [k] lock_is_held
                   |
                   --- lock_is_held
                       __might_sleep
                       mutex_lock_nested
                       perf_event_for_each_child
                       perf_ioctl
                       do_vfs_ioctl
                       sys_ioctl
                       system_call_fastpath
                       ioctl
                       cmd_record
                       run_builtin
                       main
                       __libc_start_main

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:32:26 -03:00
Frederic Weisbecker
0983cc0dbc perf tools: Fix trace events storms due to weight demux
Trace events have a period (weight) of 1 by default. This can be
overriden on events definition by using the __perf_count() macro.

For example, the sched_stat_runtime() is weighted with the runtime of
the task that fired the event.

By default, perf handles such weighted event by dividing it into
individual events carrying a weight of 1. For example if
sched_stat_runtime is fired and the task has run 5000000 nsecs, perf
divides it into 5000000 events in the buffer.

This behaviour makes weighted events unusable because they quickly
fullfill the buffers and we lose most events.

The commit 5d81e5cfb3 ("events: Don't
divide events if it has field period") solves this problem by sending
only one event when PERF_SAMPLE_PERIOD flag is set. The weight is
carried in the sample itself such that we don't need to demultiplex it
anymore.

This patch provides the last missing piece to use this feature by
setting PERF_SAMPLE_PERIOD from perf tools when we deal with trace
events.

Before:
	$ ./perf record -e sched:* -a sleep 1
	[ perf record: Woken up 3 times to write data ]
	[ perf record: Captured and wrote 1.619 MB perf.data (~70749 samples) ]
	Warning:
	Processed 16909 events and lost 1 chunks!

	Check IO/CPU overload!

	$ ./perf script
	perf  1894 [003]   824.898327: sched_migrate_task: comm=perf pid=1898 prio=120 orig_cpu=2 dest_cpu=0
	perf  1894 [003]   824.898335: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898336: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898337: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898338: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898339: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898340: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898341: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	[...]

After:
	$ ./perf record -e sched:* -a sleep 1
	[ perf record: Woken up 1 times to write data ]
	[ perf record: Captured and wrote 0.074 MB perf.data (~3228 samples) ]

	$ ./perf script

	perf  1461 [000]   554.286957: sched_migrate_task: comm=perf pid=1465 prio=120 orig_cpu=3 dest_cpu=1
	perf  1461 [000]   554.286964: sched_stat_sleep: comm=perf pid=1465 delay=133047190 [ns]
	perf  1461 [000]   554.286967: sched_wakeup: comm=perf pid=1465 prio=120 success=1 target_cpu=001
	swapper     0 [001]   554.286976: sched_stat_wait: comm=perf pid=1465 delay=0 [ns]
	swapper     0 [001]   554.286983: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=perf
	[...]

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:32:06 -03:00
Frederic Weisbecker
8760db726e perf hists: Return correct number of characters printed in callchain
Include the omitted number of characters printed for the first entry.

Not that it really matters because nobody seem to care about the number
of printed characters for now. But just in case.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:31:37 -03:00
David Ahern
78b961ff8e perf tools: Dump exclude_{guest,host}, precise_ip header info too
Adds the attributes to the event line in the header dump.
From:
 event : name = cycles, type = 0, config = 0x0, config1 = 0x0,
      config2 = 0x0, excl_usr = 0, excl_kern = 0, ...
to
  event : name = cycles, type = 0, config = 0x0, config1 = 0x0,
      config2 = 0x0, excl_usr = 0, excl_kern = 0, excl_host = 0,
      excl_guest = 0, precise_ip = 0, ...

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1342826756-64663-8-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-07-25 11:31:19 -03:00