kernel/tools/perf/util/mmap.c, branch linux-4.17.y

perf mmap: Be consistent when checking for an unmaped ring buffer

2018-03-27T16:13:38Z

The previous patch is insufficient to cure the reported 'perf trace' segfault, as it only cures the perf_mmap__read_done() case, moving the segfault to perf_mmap__read_init() functio, fix it by doing the same refcount check. Cc: Adrian Hunter Cc: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Cc: Wang Nan Fixes: 8872481bd048 ("perf mmap: Introduce perf_mmap__read_init()") Link: https://lkml.kernel.org/r/20180326144127.GF18897@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Fix accessing unmapped mmap in perf_mmap__read_done()

2018-03-27T16:13:38Z

There is a segmentation fault when running 'perf trace'. For example: [root@jouet e]# perf trace -e *chdir -o /tmp/bla perf report --ignore-vmlinux -i ../perf.data The perf_mmap__consume() could unmap the mmap. It needs to check the refcnt in perf_mmap__read_done(). Reported-by: Arnaldo Carvalho de Melo Signed-off-by: Kan Liang Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Fixes: ee023de05f35 ("perf mmap: Introduce perf_mmap__read_done()") Link: http://lkml.kernel.org/r/1522071729-16776-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Discard head in overwrite_rb_find_range()

2018-03-16T19:33:05Z

In overwrite mode, start will be set to head in perf_mmap__read_init(). Therefore, there is no need to set the start one more time in overwrite_rb_find_range() and *start can be used as head instead of passing head to overwrite_rb_find_range(). Signed-off-by: Yisheng Xie Reviewed-by: Kan Liang Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1520944274-37001-1-git-send-email-xieyisheng1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Simplify perf_mmap__read_init()

2018-03-08T13:05:53Z

It isn't necessary to pass the 'start', 'end' and 'overwrite' arguments to perf_mmap__read_init(). The data is stored in the struct perf_mmap. Discard the parameters. Signed-off-by: Kan Liang Suggested-by: Arnaldo Carvalho de Melo Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1520350567-80082-8-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Simplify perf_mmap__read_event()

2018-03-08T13:05:53Z

It isn't necessary to pass the 'overwrite', 'start' and 'end' argument to perf_mmap__read_event(). Discard them. Signed-off-by: Kan Liang Suggested-by: Arnaldo Carvalho de Melo Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1520350567-80082-7-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Simplify perf_mmap__consume()

2018-03-08T13:05:52Z

It isn't necessary to pass the 'overwrite' argument to perf_mmap__consume(). Discard it. Signed-off-by: Kan Liang Suggested-by: Arnaldo Carvalho de Melo Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1520350567-80082-6-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Use stored 'overwrite' in perf_mmap__consume()

2018-03-08T13:05:52Z

The 'overwrite' is set at allocation. It will not be changed. Using it to replace the parameter of perf_mmap__consume(). The parameters will be discarded later. No functional change. Signed-off-by: Kan Liang Suggested-by: Arnaldo Carvalho de Melo Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1520350567-80082-5-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Use the stored data in perf_mmap__read_event()

2018-03-08T13:05:51Z

Using the 'start', 'end' and 'overwrite' which are stored in struct perf_mmap to replace the parameters of perf_mmap__read_event(). The parameters will be discarded later. No functional change. Signed-off-by: Kan Liang Suggested-by: Arnaldo Carvalho de Melo Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1520350567-80082-4-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Use the stored scope data in perf_mmap__push()

2018-03-08T13:05:51Z

Using the 'start' and 'end' which are stored in struct perf_mmap to replace the temporary 'start' and 'end'. The temporary variables will be discarded later. It doesn't need to pass 'overwrite' to perf_mmap__push(). It's stored in struct perf_mmap. Signed-off-by: Kan Liang Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1520350567-80082-3-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Store mmap scope in struct perf_mmap()

2018-03-08T13:05:50Z

There is too much boilerplate in the perf_mmap__read*() interfaces. The 'start' and 'end' variables should be stored in struct perf_mmap at initialization. They will be used later. The old 'startp' and 'endp' pointers are used by perf_mmap__read_event() now. They cannot be removed. So the old 'startp/endp' and new 'md->start/md->end' will exist simultaneously now. The old one will be removed later. Signed-off-by: Kan Liang Suggested-by: Arnaldo Carvalho de Melo Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1520350567-80082-2-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo