Hi Michael, Few nitpicks :-) (wording of the log message I guess is up to Thomas, I won't comment on that)
> lib/librte_eal/common/eal_private.h | 36 > ++++++++++++++++++++++++++++++ > lib/librte_eal/linuxapp/eal/eal_pci_vfio.c | 24 +++++++++++++++++--- > 2 files changed, 57 insertions(+), 3 deletions(-) > > diff --git a/lib/librte_eal/common/eal_private.h > b/lib/librte_eal/common/eal_private.h > index 232fcec..e741bdb 100644 > --- a/lib/librte_eal/common/eal_private.h > +++ b/lib/librte_eal/common/eal_private.h > @@ -35,6 +35,7 @@ > #define _EAL_PRIVATE_H_ > > #include <stdio.h> > +#include <string.h> > > /** > * Initialize the memzone subsystem (private to eal). > @@ -203,4 +204,39 @@ int rte_eal_alarm_init(void); > */ > int rte_eal_dev_init(void); > > +/** > + * Function is to check if the kernel module(like, vfio, > +vfio_iommu_type1, > + * etc.) loaded. > + * > + * @param module_name > + * The module's name which need to be checked > + * > + * @return > + * -1 means error happens(NULL pointer or open failure) > + * 0 means the module not loaded > + * 1 means the module loaded > + */ > +static inline int > +rte_eal_check_module(const char *module_name) { > + char mod_name[30]; /* Any module names can be longer than 30 > bytes? */ > + int ret = 0; > + > + if (NULL == module_name) > + return -1; > + FILE * fd = fopen("/proc/modules", "r"); > + if (fd == NULL) > + return -1; Can we add RTE_LOG statement here, with an strerror(errno) like in other places? Fopen failed, we should at least know why :-) > + while(!feof(fd)) { > + fscanf(fd, "%s %*[^\n]", mod_name); > + if(!strcmp(mod_name, module_name)) { Probably should use strncmp instead of strcmp. > + ret = 1; > + break; > + } > + } > + fclose(fd); > + > + return ret; > +} > + > #endif /* _EAL_PRIVATE_H_ */ > diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c > b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c > index c1246e8..52ab2d0 100644 > --- a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c > +++ b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c > @@ -44,6 +44,7 @@ > #include <rte_tailq.h> > #include <rte_eal_memconfig.h> > #include <rte_malloc.h> > +#include <eal_private.h> > > #include "eal_filesystem.h" > #include "eal_pci_init.h" > @@ -339,10 +340,13 @@ pci_vfio_get_container_fd(void) > ret = ioctl(vfio_container_fd, VFIO_CHECK_EXTENSION, > VFIO_TYPE1_IOMMU); > if (ret != 1) { > if (ret < 0) > - RTE_LOG(ERR, EAL, " could not get IOMMU > type, " > - "error %i (%s)\n", errno, > strerror(errno)); > + RTE_LOG(ERR, EAL, " could not get IOMMU > type," > + " error %i (%s)\n", errno, > + strerror(errno)); > else > - RTE_LOG(ERR, EAL, " unsupported IOMMU > type!\n"); > + RTE_LOG(ERR, EAL, " unsupported IOMMU > type! " > + "expect: VFIO_TYPE1_IOMMU, " > + "actual: %d\n", ret); I'm not even sure we need this "expected" bit at all. We don't get back the IOMMU type VFIO currently supports; rather, this code checks if VFIO's support for VFIO_TYPE1_IOMMU is enabled or not. So I would change the error message to something more descriptive, such as " required IOMMU type support not present in VFIO!\n", and get rid of the "expected". > close(vfio_container_fd); > return -1; > } > @@ -788,6 +792,20 @@ pci_vfio_enable(void) > vfio_cfg.vfio_groups[i].fd = -1; > vfio_cfg.vfio_groups[i].group_no = -1; > } > + > + /* return error directly */ > + if (rte_eal_check_module("vfio") == -1 || > + rte_eal_check_module("vfio_iommu_type1") == -1) > + return -1; > + > + /* return 0 if not all VFIO modules loaded */ > + if (rte_eal_check_module("vfio") == 0 || > + rte_eal_check_module("vfio_iommu_type1") == 0) { > + RTE_LOG(INFO, EAL, "VFIO modules not all loaded," > + " skip VFIO support ...\n"); > + return 0; > + } Can we perhaps make one call per module instead of two? i.e. something like: int vfio_ret, vfio_ type1_ret; vfio_ret = rte_eal_check_module("vfio"); vfio_type1_ret = rte_eal_check_module("vfio_iommu_type1"); if (vfio_ret == -1 || vfio_type1_ret == -1) return -1; else if (vfio_ret == 0 || vfio_type1_ret == 0) { .... return 0; } > + > vfio_cfg.vfio_container_fd = pci_vfio_get_container_fd(); > > /* check if we have VFIO driver enabled */ > -- > 1.9.3