Add a new EAL option enabling manual probing in the EAL.
This command line option will configure the EAL so that buses
will not trigger their probe step on their own.
Applications are then expected to hotplug devices as they see fit.
Devices declared on the command line by the user (using -w and --vdev),
will be probed using the hotplug API, in the order they are declared.
This has the effect of offering a way for users to control probe order
of their devices, for drivers requiring it.
Signed-off-by: Gaetan Rivet <gaetan.rivet@6wind.com>
---
I haven't heard many opinions on the matter, please shout if you see an issue
with this approach.
@Slava: I have tested rather quickly that it does not break anything,
and that it works as intended for basic cases.
Can you test it further for your use-case and tell me if it works fine?
Beyond the obvious difference between both probe mode, something to keep in mind:
while using -w on invalid devices would not block (PCI) bus probing, it will stop manual
probing in its track. All devices need to exist and be valid device IDs.
v2: fixed a few typos, map file (and used Travis to validate).
Slava, are you able to test this patch?
doc/guides/rel_notes/release_19_11.rst | 9 +++++++
lib/librte_eal/common/eal_common_bus.c | 6 +++++
lib/librte_eal/common/eal_common_dev.c | 41 ++++++++++++++++++++++++++++++
lib/librte_eal/common/eal_common_options.c | 8 ++++++
lib/librte_eal/common/eal_internal_cfg.h | 1 +
lib/librte_eal/common/eal_options.h | 2 ++
lib/librte_eal/common/eal_private.h | 9 +++++++
lib/librte_eal/common/include/rte_eal.h | 17 +++++++++++++
lib/librte_eal/freebsd/eal/eal.c | 5 ++++
lib/librte_eal/linux/eal/eal.c | 5 ++++
lib/librte_eal/rte_eal_version.map | 7 +++++
11 files changed, 110 insertions(+)
@@ -56,6 +56,15 @@ New Features
Also, make sure to start the actual text at the margin.
=========================================================
+* **EAL will now propose to enforce manual probing of devices.**
+
+ Previously, a user could not force an order when probing declared devices.
+ This could cause issues for drivers depending on another device being present.
+ A new option ``--manual-probe`` is now available to do just that.
+ This new option relies on the device bus supporting hotplug. It can
+ also be used to disable automatic probing from the ``PCI`` bus without
+ having to disable the whole bus.
+
Removed Items
-------------
@@ -6,6 +6,7 @@
#include <string.h>
#include <sys/queue.h>
+#include <rte_eal.h>
#include <rte_bus.h>
#include <rte_debug.h>
#include <rte_string_fns.h>
@@ -63,6 +64,11 @@ rte_bus_probe(void)
int ret;
struct rte_bus *bus, *vbus = NULL;
+ if (rte_eal_manual_probe()) {
+ RTE_LOG(DEBUG, EAL, "Manual probing enabled.\n");
+ return rte_dev_probe_devargs_list();
+ }
+
TAILQ_FOREACH(bus, &rte_bus_list, next) {
if (!strcmp(bus->name, "vdev")) {
vbus = bus;
@@ -109,6 +109,47 @@ build_devargs(const char *busname, const char *devname,
}
int
+rte_dev_probe_devargs_list(void)
+{
+ struct rte_device *dev;
+ struct rte_devargs *da;
+ int ret;
+
+ RTE_EAL_DEVARGS_FOREACH(NULL, da) {
+ dev = da->bus->find_device(NULL, cmp_dev_name, da->name);
+ if (dev == NULL) {
+ RTE_LOG(ERR, EAL, "Unable to find device %s on bus %s\n",
+ da->name, da->bus->name);
+ continue;
+ }
+
+ if (rte_dev_is_probed(dev))
+ continue;
+
+ if (dev->bus->plug == NULL) {
+ RTE_LOG(ERR, EAL, "Manual probing (hotplug) not supported by bus %s, "
+ "required by device %s\n",
+ dev->bus->name, dev->name);
+ continue;
+ }
+
+ ret = dev->bus->plug(dev);
+ /* Ignore positive return values, they are possibly
+ * triggered by blacklisted devices on the PCI bus. Probing
+ * should then continue.
+ */
+ if (ret < 0) {
+ RTE_LOG(ERR, EAL, "Driver cannot attach device %s\n",
+ dev->name);
+ /* Fail on first real probe error. */
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+int
rte_eal_hotplug_add(const char *busname, const char *devname,
const char *drvargs)
{
@@ -81,6 +81,7 @@ eal_long_options[] = {
{OPT_LEGACY_MEM, 0, NULL, OPT_LEGACY_MEM_NUM },
{OPT_SINGLE_FILE_SEGMENTS, 0, NULL, OPT_SINGLE_FILE_SEGMENTS_NUM},
{OPT_MATCH_ALLOCATIONS, 0, NULL, OPT_MATCH_ALLOCATIONS_NUM},
+ {OPT_MANUAL_PROBE, 0, NULL, OPT_MANUAL_PROBE_NUM },
{0, 0, NULL, 0 }
};
@@ -1408,6 +1409,9 @@ eal_parse_common_option(int opt, const char *optarg,
return -1;
}
break;
+ case OPT_MANUAL_PROBE_NUM:
+ conf->manual_probe = 1;
+ break;
/* don't know what to do, leave this to caller */
default:
@@ -1634,6 +1638,10 @@ eal_common_usage(void)
" --"OPT_VDEV" Add a virtual device.\n"
" The argument format is <driver><id>[,key=val,...]\n"
" (ex: --vdev=net_pcap0,iface=eth2).\n"
+ " --"OPT_MANUAL_PROBE" Enable manual probing.\n"
+ " Disable probe step for all buses.\n"
+ " Devices will need to be probed using the hotplug API.\n"
+ " PCI and vdev declarations will be treated in order as hotplug commands.\n"
" --"OPT_IOVA_MODE" Set IOVA mode. 'pa' for IOVA_PA\n"
" 'va' for IOVA_VA\n"
" -d LIB.so|DIR Add a driver or driver directory\n"
@@ -44,6 +44,7 @@ struct internal_config {
unsigned hugepage_unlink; /**< true to unlink backing files */
volatile unsigned no_pci; /**< true to disable PCI */
volatile unsigned no_hpet; /**< true to disable HPET */
+ volatile unsigned manual_probe; /**< true to enable manual device probing. */
volatile unsigned vmware_tsc_map; /**< true to use VMware TSC mapping
* instead of native TSC */
volatile unsigned no_shconf; /**< true if there is no shared config */
@@ -69,6 +69,8 @@ enum {
OPT_IOVA_MODE_NUM,
#define OPT_MATCH_ALLOCATIONS "match-allocations"
OPT_MATCH_ALLOCATIONS_NUM,
+#define OPT_MANUAL_PROBE "manual-probe"
+ OPT_MANUAL_PROBE_NUM,
OPT_LONG_MAX_NUM
};
@@ -381,4 +381,13 @@ rte_option_init(void);
void
rte_option_usage(void);
+/**
+ * Go through the devargs list and probe everything in order.
+ *
+ * @return
+ * 0 on success, negative on error.
+ */
+int
+rte_dev_probe_devargs_list(void);
+
#endif /* _EAL_PRIVATE_H_ */
@@ -465,6 +465,23 @@ int rte_eal_has_hugepages(void);
int rte_eal_has_pci(void);
/**
+ * Whether EAL probe is manual.
+ * Enabled by the --manual-probe option.
+ *
+ * When manual probing is enabled, batched bus probe of
+ * their devices is disabled. All devices need to be probed
+ * using the proper rte_dev API.
+ *
+ * In this mode, devices declared on the command line will
+ * be probed using the bus hotplug API. It is used to enforce
+ * a specific probe order.
+ *
+ * @return
+ * Nonzero if manual device probing is enabled.
+ */
+int rte_eal_manual_probe(void);
+
+/**
* Whether the EAL was asked to create UIO device.
*
* @return
@@ -961,6 +961,11 @@ int rte_eal_has_pci(void)
return !internal_config.no_pci;
}
+int rte_eal_manual_probe(void)
+{
+ return internal_config.manual_probe;
+}
+
int rte_eal_create_uio_dev(void)
{
return internal_config.create_uio_dev;
@@ -1376,6 +1376,11 @@ int rte_eal_create_uio_dev(void)
return internal_config.create_uio_dev;
}
+int rte_eal_manual_probe(void)
+{
+ return internal_config.manual_probe;
+}
+
enum rte_intr_mode
rte_eal_vfio_intr_mode(void)
{
@@ -312,6 +312,13 @@ DPDK_19.08 {
} DPDK_19.05;
+DPDK_19.11 {
+ global:
+
+ rte_eal_manual_probe;
+
+} DPDK_19.05;
+
EXPERIMENTAL {
global: