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| author | Ingo Molnar <mingo@elte.hu> | 2009-05-24 09:02:37 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-05-24 09:02:37 +0200 |
| commit | a3862d3f814ce7dfca9eed56ac23d29db3aee8d5 (patch) | |
| tree | 5cbc8c2cb9b11acb5bc21009d27da3978c1c0db2 /kernel/perf_counter.c | |
| parent | c2990a2a582d73562d4dcf2502c39892a19a691d (diff) | |
| download | lwn-a3862d3f814ce7dfca9eed56ac23d29db3aee8d5.tar.gz lwn-a3862d3f814ce7dfca9eed56ac23d29db3aee8d5.zip | |
perf_counter: Increase mmap limit
In a default 'perf top' run the tool will create a counter for
each online CPU. With enough CPUs this will eventually exhaust
the default limit.
So scale it up with the number of online CPUs.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/perf_counter.c')
| -rw-r--r-- | kernel/perf_counter.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index cb4062559b47..6cdf8248eda2 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1704,6 +1704,12 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) user_extra = nr_pages + 1; user_lock_limit = sysctl_perf_counter_mlock >> (PAGE_SHIFT - 10); + + /* + * Increase the limit linearly with more CPUs: + */ + user_lock_limit *= num_online_cpus(); + user_locked = atomic_long_read(&user->locked_vm) + user_extra; extra = 0; |