From: Kyle McMartin Date: Mon, 27 Feb 2012 22:02:56 +0000 (-0500) Subject: IB/ehca: Fix ilog2() compile failure X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=bd50f8924c684f84416fb58c11eb24619b041f25;p=deliverable%2Flinux.git IB/ehca: Fix ilog2() compile failure I'm getting compile failures building this driver, which I narrowed down to the ilog2 call in ehca_get_max_hwpage_size... ERROR: ".____ilog2_NaN" [drivers/infiniband/hw/ehca/ib_ehca.ko] undefined! make[1]: *** [__modpost] Error 1 make: *** [modules] Error 2 The use of shca->hca_cap_mr_pgsize is confusing the compiler, and resulting in the __builtin_constant_p in ilog2 going insane. I tried making it take the u32 pgsize as an argument and the expansion of shca->_pgsize in the caller, but that failed as well. With this patch in place, the driver compiles on my GCC 4.6.2 here. Suggested-by: Roland Dreier Signed-off-by: Kyle McMartin Signed-off-by: Roland Dreier --- diff --git a/drivers/infiniband/hw/ehca/ehca_mrmw.c b/drivers/infiniband/hw/ehca/ehca_mrmw.c index 43cae84005f0..b781b2cb0624 100644 --- a/drivers/infiniband/hw/ehca/ehca_mrmw.c +++ b/drivers/infiniband/hw/ehca/ehca_mrmw.c @@ -112,7 +112,7 @@ static u32 ehca_encode_hwpage_size(u32 pgsize) static u64 ehca_get_max_hwpage_size(struct ehca_shca *shca) { - return 1UL << ilog2(shca->hca_cap_mr_pgsize); + return rounddown_pow_of_two(shca->hca_cap_mr_pgsize); } static struct ehca_mr *ehca_mr_new(void)