diff options
| author | Kaixu Xia <xiakaixu@huawei.com> | 2015-01-27 10:55:12 +0100 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2015-02-13 15:40:30 +0100 |
| commit | 74390aa5567827add5058a3b26eff0ed06a629ba (patch) | |
| tree | e0deaad7ad8a9667f277f334282358e89dd4a6b6 /kernel/events | |
| parent | perf tools: Fix a bug of segmentation fault (diff) | |
| download | linux-74390aa5567827add5058a3b26eff0ed06a629ba.tar.xz linux-74390aa5567827add5058a3b26eff0ed06a629ba.zip | |
perf: Remove the extra validity check on nr_pages
The function is_power_of_2() also do the check on nr_pages, so the first
check performed is unnecessary. On the other hand, the key point is to
ensure @nr_pages is a power-of-two number and mostly @nr_pages is a
nonzero value, so in the most cases, the function is_power_of_2() will
be called.
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Link: http://lkml.kernel.org/r/1422352512-75150-1-git-send-email-xiakaixu@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/core.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 7f2fbb8b5069..0969c9b67eec 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4420,7 +4420,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) * If we have rb pages ensure they're a power-of-two number, so we * can do bitmasks instead of modulo. */ - if (nr_pages != 0 && !is_power_of_2(nr_pages)) + if (!is_power_of_2(nr_pages)) return -EINVAL; if (vma_size != PAGE_SIZE * (1 + nr_pages)) |