perf synthetic-events: Fix divide by zero in perf_event__synthesize_threads

If scandir() finds no matching tasks in /proc, n is 0. If thread_nr is > 1,
we bypass the single-thread fast path and then clamp thread_nr to n, making
it 0. This results in a divide by zero when calculating num_per_thread.

Handle n <= 1 early to use the single-thread fast path and prevent the
crash.

Fixes: 340b47f510bb ("perf top: Implement multithreading for perf_event__synthesize_threads")
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

0 files changed, 0 insertions, 0 deletions