powerpc: Fix hcall tracepoint recursion
authorAnton Blanchard <anton@samba.org>
Thu, 21 Oct 2010 00:52:12 +0000 (00:52 +0000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Mon, 7 Feb 2011 02:06:08 +0000 (13:06 +1100)
commit57cdfdf829a850a317425ed93c6a576c9ee6329c
tree80e1e9e5f742e2a67ed4e43e6cc2e2823f27e72d
parent429f4d8d20b91e4a6c239f951c06a56a6ac22957
powerpc: Fix hcall tracepoint recursion

Spinlocks on shared processor partitions use H_YIELD to notify the
hypervisor we are waiting on another virtual CPU. Unfortunately this means
the hcall tracepoints can recurse.

The patch below adds a percpu depth and checks it on both the entry and
exit hcall tracepoints.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@kernel.org
arch/powerpc/platforms/pseries/lpar.c