From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bjorn Helgaas Subject: Re: [PATCH v4 8/8] linux/log2.h: Use roundup/dow_pow_two() on 64bit calculations Date: Thu, 5 Dec 2019 14:38:45 -0600 Message-ID: <20191205203845.GA243596@google.com> References: <20191203114743.1294-9-nsaenzjulienne@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20191203114743.1294-9-nsaenzjulienne@suse.de> Sender: linux-kernel-owner@vger.kernel.org To: Nicolas Saenz Julienne Cc: andrew.murray@arm.com, maz@kernel.org, linux-kernel@vger.kernel.org, Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Tariq Toukan , Rob Herring , Frank Rowand , Florian Fainelli , bcm-kernel-feedback-list@broadcom.com, Eric Anholt , Stefan Wahren , Shawn Lin , Heiko Stuebner , Christoph Hellwig , Marek Szyprowski , Robin Murphy , james.quinlan@broadcom.com, mbrugger@suse.com, phil@raspberrypi.org, jeremy.linton@arm.com, linux-pci@vger.kernel.or List-Id: linux-rockchip.vger.kernel.org The subject contains a couple typos: it's missing "of" and it's missing the "n" on "down". On Tue, Dec 03, 2019 at 12:47:41PM +0100, Nicolas Saenz Julienne wrote: > The function now is safe to use while expecting a 64bit value. Use it > where relevant. Please include the function names ("roundup_pow_of_two()", "rounddown_pow_of_two()") in the changelog so it is self-contained and doesn't depend on the subject. > Signed-off-by: Nicolas Saenz Julienne With the nits above and below addressed, Acked-by: Bjorn Helgaas # drivers/pci > --- > drivers/acpi/arm64/iort.c | 2 +- > drivers/net/ethernet/mellanox/mlx4/en_clock.c | 3 ++- > drivers/of/device.c | 3 ++- > drivers/pci/controller/cadence/pcie-cadence-ep.c | 3 ++- > drivers/pci/controller/cadence/pcie-cadence.c | 3 ++- > drivers/pci/controller/pcie-brcmstb.c | 3 ++- > drivers/pci/controller/pcie-rockchip-ep.c | 5 +++-- > kernel/dma/direct.c | 2 +- > 8 files changed, 15 insertions(+), 9 deletions(-) > --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c > +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c > @@ -10,6 +10,7 @@ > #include > #include > #include > +#include > > #include "pcie-cadence.h" > > @@ -65,7 +66,7 @@ static int cdns_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, > * roundup_pow_of_two() returns an unsigned long, which is not suited > * for 64bit values. > */ Please remove the comment above since it no longer applies. > - sz = 1ULL << fls64(sz - 1); > + sz = roundup_pow_of_two(sz); > aperture = ilog2(sz) - 7; /* 128B -> 0, 256B -> 1, 512B -> 2, ... */ > > if ((flags & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) { > diff --git a/drivers/pci/controller/cadence/pcie-cadence.c b/drivers/pci/controller/cadence/pcie-cadence.c > index cd795f6fc1e2..b1689f725b41 100644 > --- a/drivers/pci/controller/cadence/pcie-cadence.c > +++ b/drivers/pci/controller/cadence/pcie-cadence.c > @@ -4,6 +4,7 @@ > // Author: Cyrille Pitchen > > #include > +#include > > #include "pcie-cadence.h" > > @@ -15,7 +16,7 @@ void cdns_pcie_set_outbound_region(struct cdns_pcie *pcie, u8 fn, > * roundup_pow_of_two() returns an unsigned long, which is not suited > * for 64bit values. > */ Same here. > - u64 sz = 1ULL << fls64(size - 1); > + u64 sz = roundup_pow_of_two(size); > int nbits = ilog2(sz); > u32 addr0, addr1, desc0, desc1; > > --- a/drivers/pci/controller/pcie-rockchip-ep.c > +++ b/drivers/pci/controller/pcie-rockchip-ep.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > > #include "pcie-rockchip.h" > > @@ -70,7 +71,7 @@ static void rockchip_pcie_prog_ep_ob_atu(struct rockchip_pcie *rockchip, u8 fn, > u32 r, u32 type, u64 cpu_addr, > u64 pci_addr, size_t size) > { > - u64 sz = 1ULL << fls64(size - 1); > + u64 sz = roundup_pow_of_two(size); > int num_pass_bits = ilog2(sz); > u32 addr0, addr1, desc0, desc1; > bool is_nor_msg = (type == AXI_WRAPPER_NOR_MSG); > @@ -176,7 +177,7 @@ static int rockchip_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, > * roundup_pow_of_two() returns an unsigned long, which is not suited > * for 64bit values. > */ And here. > - sz = 1ULL << fls64(sz - 1); > + sz = roundup_pow_of_two(sz); > aperture = ilog2(sz) - 7; /* 128B -> 0, 256B -> 1, 512B -> 2, ... */ > > if ((flags & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) { > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index 6af7ae83c4ad..056886c4efec 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -53,7 +53,7 @@ u64 dma_direct_get_required_mask(struct device *dev) > { > u64 max_dma = phys_to_dma_direct(dev, (max_pfn - 1) << PAGE_SHIFT); > > - return (1ULL << (fls64(max_dma) - 1)) * 2 - 1; > + return rounddown_pow_of_two(max_dma) * 2 - 1; Personally I would probably make this one a separate patch since it's qualitatively different than the others and it would avoid the slight awkwardness of the non-greppable "roundup/down_pow_of_two()" construction in the commit subject. But it's fine either way. > } > > static gfp_t __dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, > -- > 2.24.0 >