| Message ID | 20220218151935.31688-1-janusz.krzysztofik@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [i-g-t] lib/igt_device: Add support for accessing unbound VF PCI devices | expand |
Quoting Janusz Krzysztofik (2022-02-18 15:19:35) > @@ -206,15 +229,19 @@ static struct pci_device *__igt_device_get_pci_device(int fd) > igt_warn("Couldn't find PCI device %04x:%02x:%02x:%02x\n", > pci_addr.domain, pci_addr.bus, > pci_addr.device, pci_addr.function); > - return NULL; > + goto cleanup; > } > > if (pci_device_probe(pci_dev)) { > igt_warn("Couldn't probe PCI device\n"); > - return NULL; > + goto cleanup; > } > > return pci_dev; > + > +cleanup: > + pci_system_cleanup(); This is a global cleanup of libpciaccess iirc, such that if anyone else was using the library they would be affected. > + return NULL; > }
Hi Chris, On Friday, 18 February 2022 17:03:01 CET Chris Wilson wrote: > Quoting Janusz Krzysztofik (2022-02-18 15:19:35) > > @@ -206,15 +229,19 @@ static struct pci_device *__igt_device_get_pci_device(int fd) > > igt_warn("Couldn't find PCI device %04x:%02x:%02x:%02x\n", > > pci_addr.domain, pci_addr.bus, > > pci_addr.device, pci_addr.function); > > - return NULL; > > + goto cleanup; > > } > > > > if (pci_device_probe(pci_dev)) { > > igt_warn("Couldn't probe PCI device\n"); > > - return NULL; > > + goto cleanup; > > } > > > > return pci_dev; > > + > > +cleanup: > > + pci_system_cleanup(); > > This is a global cleanup of libpciaccess iirc, such that if anyone else > was using the library they would be affected. Right, but shouldn't we also drop pci_system_init() from here and request users to manage initialization and cleanup of that data themselves? On each call pci_system_init() abandons existing data and overwrites a pointer to it with that of newly allocated memory, then tests calling igt_device_get_pci_device() multiple times are going to suffer from significant memory leaking. Thanks, Janusz > > > + return NULL; > > } >
Quoting Janusz Krzysztofik (2022-02-18 17:08:41) > Hi Chris, > > On Friday, 18 February 2022 17:03:01 CET Chris Wilson wrote: > > Quoting Janusz Krzysztofik (2022-02-18 15:19:35) > > > @@ -206,15 +229,19 @@ static struct pci_device *__igt_device_get_pci_device(int fd) > > > igt_warn("Couldn't find PCI device %04x:%02x:%02x:%02x\n", > > > pci_addr.domain, pci_addr.bus, > > > pci_addr.device, pci_addr.function); > > > - return NULL; > > > + goto cleanup; > > > } > > > > > > if (pci_device_probe(pci_dev)) { > > > igt_warn("Couldn't probe PCI device\n"); > > > - return NULL; > > > + goto cleanup; > > > } > > > > > > return pci_dev; > > > + > > > +cleanup: > > > + pci_system_cleanup(); > > > > This is a global cleanup of libpciaccess iirc, such that if anyone else > > was using the library they would be affected. > > Right, but shouldn't we also drop pci_system_init() from here and request > users to manage initialization and cleanup of that data themselves? On each > call pci_system_init() abandons existing data and overwrites a pointer to it > with that of newly allocated memory, then tests calling > igt_device_get_pci_device() multiple times are going to suffer from > significant memory leaking. Right, I thought it only inited once -- I just remember the issue with calling pci_system_cleanup() while others were still using it. Stick the call to init in an __attribute__((constructor)) or pthread_once. -Chris
diff --git a/lib/igt_device.c b/lib/igt_device.c index 07bb0a0d41..56f66afc6f 100644 --- a/lib/igt_device.c +++ b/lib/igt_device.c @@ -149,9 +149,9 @@ struct igt_pci_addr { unsigned int function; }; -static int igt_device_get_pci_addr(int fd, struct igt_pci_addr *pci) +static int igt_device_get_pci_addr(int fd, unsigned int vf_id, struct igt_pci_addr *pci) { - char path[IGT_DEV_PATH_LEN]; + char link[20], path[IGT_DEV_PATH_LEN]; char *buf; int sysfs; int len; @@ -159,11 +159,21 @@ static int igt_device_get_pci_addr(int fd, struct igt_pci_addr *pci) if (!igt_device_is_pci(fd)) return -ENODEV; + if (vf_id) + len = snprintf(link, sizeof(link), "device/virtfn%u", vf_id - 1); + else + len = snprintf(link, sizeof(link), "device"); + if (igt_warn_on_f(len > sizeof(link) || link[len -1], + "IGT bug: insufficient buffer space for rendering PCI device link name\n")) + return -ENOSPC; + else if (igt_debug_on_f(len < 0, "unexpected failure from snprintf()\n")) + return len; + sysfs = igt_sysfs_open(fd); if (sysfs == -1) return -ENOENT; - len = readlinkat(sysfs, "device", path, sizeof(path) - 1); + len = readlinkat(sysfs, link, path, sizeof(path) - 1); close(sysfs); if (len == -1) return -ENOENT; @@ -183,12 +193,25 @@ static int igt_device_get_pci_addr(int fd, struct igt_pci_addr *pci) return 0; } -static struct pci_device *__igt_device_get_pci_device(int fd) +/** + * __igt_device_get_pci_device: + * + * @fd: DRM device file descriptor + * @vf_id: virtual function number (0 if native or PF) + * + * Looks up the graphics pci device using libpciaccess. + * Since pci_system_init() is called, users are expected to call pci_sytem_clenup() after use + * unless an error occurs and NULL is returned. + * + * Returns: + * The pci_device, NULL on any failures. + */ +struct pci_device *__igt_device_get_pci_device(int fd, unsigned int vf_id) { struct igt_pci_addr pci_addr; struct pci_device *pci_dev; - if (igt_device_get_pci_addr(fd, &pci_addr)) { + if (igt_device_get_pci_addr(fd, vf_id, &pci_addr)) { igt_warn("Unable to find device PCI address\n"); return NULL; } @@ -206,15 +229,19 @@ static struct pci_device *__igt_device_get_pci_device(int fd) igt_warn("Couldn't find PCI device %04x:%02x:%02x:%02x\n", pci_addr.domain, pci_addr.bus, pci_addr.device, pci_addr.function); - return NULL; + goto cleanup; } if (pci_device_probe(pci_dev)) { igt_warn("Couldn't probe PCI device\n"); - return NULL; + goto cleanup; } return pci_dev; + +cleanup: + pci_system_cleanup(); + return NULL; } /** @@ -223,6 +250,7 @@ static struct pci_device *__igt_device_get_pci_device(int fd) * @fd: the device * * Looks up the main graphics pci device using libpciaccess. + * Since pci_system_init() is called, users are expected to call pci_sytem_clenup() after use. * * Returns: * The pci_device, skips the test on any failures. @@ -231,7 +259,7 @@ struct pci_device *igt_device_get_pci_device(int fd) { struct pci_device *pci_dev; - pci_dev = __igt_device_get_pci_device(fd); + pci_dev = __igt_device_get_pci_device(fd, 0); igt_require(pci_dev); return pci_dev; diff --git a/lib/igt_device.h b/lib/igt_device.h index 278ba7a9b3..1aaa840e25 100644 --- a/lib/igt_device.h +++ b/lib/igt_device.h @@ -33,5 +33,6 @@ void igt_device_drop_master(int fd); int igt_device_get_card_index(int fd); struct pci_device *igt_device_get_pci_device(int fd); +struct pci_device *__igt_device_get_pci_device(int fd, unsigned int vf_id); #endif /* __IGT_DEVICE_H__ */
The library provides igt_device_get_pci_device() function that allows to get access to a PCI device from an open DRM device file descriptor. It can be used on VF devices as long as a DRM driver is bound to them. However, SR-IOV tests may want to exercise VF PCI devices created by a PF without binding any DRM driver to them. While keeping the API of igt_device_get_pci_device() untouched, extend API of its underlying helper __igt_device_get_pci_device() with an extra argument for specifying VF ID of the requested PCI device and expose this function as public. While being at it, fix pci_system_cleanup() not called on errors and instruct users to call it for symmetry when the obtained struct pci_device is no longer needed. Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com> --- lib/igt_device.c | 44 ++++++++++++++++++++++++++++++++++++-------- lib/igt_device.h | 1 + 2 files changed, 37 insertions(+), 8 deletions(-)