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| author |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-07-14 08:34:33 +0000 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-07-15 13:38:06 -0300 |
| commit | 32a951b4fd6bbe60ef5d65930b1712321e241b27 (patch) | |
| tree | 6900abcdecfb044b93de799a1f7fcc01e9893ad4 /tools/perf/util/evsel.c | |
| parent | tools lib api fs: Use base 0 in filename__read_ull (diff) | |
| download | linux-dev-32a951b4fd6bbe60ef5d65930b1712321e241b27.tar.xz linux-dev-32a951b4fd6bbe60ef5d65930b1712321e241b27.zip | |
perf evlist: Drop redundant evsel->overwrite indicator
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 <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/evsel.c')
| -rw-r--r-- | tools/perf/util/evsel.c | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index ba0f59fa3d5d..9ac2f92ce88d 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1377,6 +1377,9 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus, int pid = -1, err; enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE; + if (perf_missing_features.write_backward && evsel->attr.write_backward) + return -EINVAL; + if (evsel->system_wide) nthreads = 1; else @@ -1407,11 +1410,6 @@ fallback_missing_features: if (perf_missing_features.lbr_flags) evsel->attr.branch_sample_type &= ~(PERF_SAMPLE_BRANCH_NO_FLAGS | PERF_SAMPLE_BRANCH_NO_CYCLES); - if (perf_missing_features.write_backward) { - if (evsel->overwrite) - return -EINVAL; - evsel->attr.write_backward = false; - } retry_sample_id: if (perf_missing_features.sample_id_all) evsel->attr.sample_id_all = 0; @@ -1513,7 +1511,7 @@ try_fallback: */ if (!perf_missing_features.write_backward && evsel->attr.write_backward) { perf_missing_features.write_backward = true; - goto fallback_missing_features; + goto out_close; } else if (!perf_missing_features.clockid_wrong && evsel->attr.use_clockid) { perf_missing_features.clockid_wrong = true; goto fallback_missing_features; @@ -2422,7 +2420,7 @@ int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target, "We found oprofile daemon running, please stop it and try again."); break; case EINVAL: - if (evsel->overwrite && perf_missing_features.write_backward) + if (evsel->attr.write_backward && perf_missing_features.write_backward) return scnprintf(msg, size, "Reading from overwrite event is not supported by this kernel."); if (perf_missing_features.clockid) return scnprintf(msg, size, "clockid feature not supported."); |