> -----Original Message----- > From: Yigit, Ferruh > Sent: Thursday, March 03, 2016 5:35 PM > To: Ananyev, Konstantin; dev at dpdk.org > Subject: Re: [dpdk-dev] [PATCH] igb_uio: use macros for array size calculation > > On 3/3/2016 5:25 PM, Ananyev, Konstantin wrote: > > > > > >> -----Original Message----- > >> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Ferruh Yigit > >> Sent: Thursday, March 03, 2016 5:08 PM > >> To: dev at dpdk.org > >> Subject: [dpdk-dev] [PATCH] igb_uio: use macros for array size calculation > >> > >> Minor code cleanup. > >> Remove array size calculations and remove unnecessary assignment. > >> > >> Signed-off-by: Ferruh Yigit <ferruh.yigit at intel.com> > >> --- > >> lib/librte_eal/linuxapp/igb_uio/igb_uio.c | 8 ++++---- > >> 1 file changed, 4 insertions(+), 4 deletions(-) > >> > >> diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > >> b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > >> index 3374e44..563c57b 100644 > >> --- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > >> +++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > >> @@ -58,7 +58,7 @@ struct rte_uio_pci_dev { > >> enum rte_intr_mode mode; > >> }; > >> > >> -static char *intr_mode = NULL; > >> +static char *intr_mode; > >> static enum rte_intr_mode igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX; > >> > >> /* sriov sysfs */ > >> @@ -332,7 +332,7 @@ igbuio_pci_setup_iomem(struct pci_dev *dev, struct > >> uio_info *info, > >> unsigned long addr, len; > >> void *internal_addr; > >> > >> - if (sizeof(info->mem) / sizeof(info->mem[0]) <= n) > >> + if (n >= MAX_UIO_MAPS) > > > > Why using hardcoded value is better than sizeof()? > > As I can see below there is a macro ARRAY_SIZE, why not to use it here then? > > Both are valid, but in uio (uio_driver.h) "mem" array defined as: > struct uio_mem mem[MAX_UIO_MAPS];
Yep, so if both are valid, why to change it a the first place? :) > > So we already know the size of the array, and it is exposed to us, why > need to calculate. Is there any benefit of calculating it? if in future definition of the mem[] would change to let say: struct uio_mem mem[X] your code would still be valid, and no need to update it. Konstantin > > Thanks, > ferruh
