linux-toradex.git/tools/perf/util/evlist.c, branch v4.8

perf evsel: Introduce constructor for cycles event

2016-07-28T21:33:20+00:00

That is the default used when no events is specified in tools, separate
it so that simpler tools that need no evlist can use it directly.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-67mwuthscwroz88x9pswcqyv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Make {pause,resume} internal helpers

2016-07-15T20:27:50+00:00

There's no user of these two function outside evlist.c. Remove them from
public namespace.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-13-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Setup backward mmap state machine

2016-07-15T20:27:49+00:00

Introduce a bkw_mmap_state state machine to evlist:

                     .________________(forbid)_____________.
                     |                                     V
 NOTREADY --(0)--> RUNNING --(1)--> DATA_PENDING --(2)--> EMPTY
                     ^  ^              |   ^               |
                     |  |__(forbid)____/   |___(forbid)___/|
                     |                                     |
                      \_________________(3)_______________/

 NOTREADY     : Backward ring buffers are not ready
 RUNNING      : Backward ring buffers are recording
 DATA_PENDING : We are required to collect data from backward ring buffers
 EMPTY        : We have collected data from backward ring buffers.

 (0): Setup backward ring buffer
 (1): Pause ring buffers for reading
 (2): Read from ring buffers
 (3): Resume ring buffers for recording

We can't avoid this complexity. Since we deliberately drop records from
overwritable ring buffer, there's no way for us to check remaining from
ring buffer itself (by checking head and old pointers). Therefore, we
need DATA_PENDING and EMPTY state to help us recording what we have done
to the ring buffer.

In record__mmap_read_evlist(), drive this state machine from DATA_PENDING
to EMPTY.

In perf_evlist__mmap_per_evsel(), drive this state machine from NOTREADY
to RUNNING when creating backward mmap.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-11-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Drop evlist->backward

2016-07-15T20:27:49+00:00

Now there's no real user of evlist->backward. Drop it. We are going to
use evlist->backward_mmap as a container for backward ring buffer.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-10-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Map backward events to backward_mmap

2016-07-15T20:27:48+00:00

In perf_evlist__mmap_per_evsel(), select backward_mmap for backward
events.  Utilize new perf_mmap APIs. Dynamically alloc backward_mmap.

Remove useless functions.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-9-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Introduce backward_mmap array for evlist

2016-07-15T20:27:48+00:00

Add backward_mmap to evlist, free it together with normal mmap.

Improve perf_evlist__pick_pc(), search backward_mmap if evlist->mmap is
not available.

This patch doesn't alloc this array. It will be allocated conditionally
in the following commits.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-8-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Extract common code in mmap failure processing

2016-07-15T20:27:47+00:00

In perf_evlist__mmap_per_cpu() and perf_evlist__mmap_per_thread(), in
case of mmap failure, successfully created maps should be cleared.

Current code uses two loops calling __perf_evlist__munmap() for each
function.

This patch extracts common code to perf_evlist__munmap_nofree() and use
previous introduced decoupled API perf_mmap__munmap(). Now
__perf_evlist__munmap() can be removed because of no user.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Record mmap cookie into fdarray private field

2016-07-15T20:27:47+00:00

Insetad of saving a index into fdarray entries private field, save the
corresponding 'struct perf_mmap' pointer, and release them directly
using perf_mmap__put().

Following commits introduce multiple mmap arrays to evlist. Without this
patch, perf_evlist__munmap_filtered() is unable to retrive correct
'struct perf_mmap' pointer.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-6-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Update mmap related APIs and helpers

2016-07-15T20:27:46+00:00

Currently, the evlist mmap related helpers and APIs accept evlist and
idx, and dereference 'struct perf_mmap' by evlist->mmap[idx]. This is
unnecessary, and force each evlist contains only one mmap array.

Following commits are going to introduce multiple mmap arrays to a
evlist.  This patch refators these APIs and helpers, introduces
functions accept perf_mmap pointer directly. New helpers and APIs are
decoupled with perf_evlist, and become perf_mmap functions (so they have
perf_mmap prefix).

Old functions are reimplemented with new functions. Some of them will be
removed in following commits.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: He Kuang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Drop redundant evsel->overwrite indicator

2016-07-15T16:38:06+00:00

evsel->overwrite indicator means an event should be put into
overwritable ring buffer. In current implementation, it equals to
evsel->attr.write_backward. To reduce compliexity, remove
evsel->overwrite, use evsel->attr.write_backward instead.

In addition, in __perf_evsel__open(), if kernel doesn't support
write_backward and user explicitly set it in evsel, don't fallback
like other missing feature, since it is meaningless to fall back to
a forward ring buffer in this case: we are unable to stably read
from an forward overwritable ring buffer.

Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Nilay Vaish 
Cc: Wang Nan 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan 
Signed-off-by: Arnaldo Carvalho de Melo