Commit-ID: 66fff22483d8542dfb4d61a28d21277bbde321e8 Gitweb: http://git.kernel.org/tip/66fff22483d8542dfb4d61a28d21277bbde321e8 Author: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> AuthorDate: Wed, 10 Jun 2009 22:53:37 +0200 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Thu, 11 Jun 2009 02:39:01 +0200 perf_counter: Annotate exit ctx recursion Ever since Paul fixed it to unclone the context before taking the ctx->lock this became a false positive, annotate it away. Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Mike Galbraith <efault@xxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- kernel/perf_counter.c | 13 ++++++++++++- 1 files changed, 12 insertions(+), 1 deletions(-) diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 51c571e..ae591a1 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -3879,7 +3879,18 @@ void perf_counter_exit_task(struct task_struct *child) spin_unlock(&child_ctx->lock); local_irq_restore(flags); - mutex_lock(&child_ctx->mutex); + /* + * We can recurse on the same lock type through: + * + * __perf_counter_exit_task() + * sync_child_counter() + * fput(parent_counter->filp) + * perf_release() + * mutex_lock(&ctx->mutex) + * + * But since its the parent context it won't be the same instance. + */ + mutex_lock_nested(&child_ctx->mutex, SINGLE_DEPTH_NESTING); again: list_for_each_entry_safe(child_counter, tmp, &child_ctx->counter_list, -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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