@@ -79,6 +79,15 @@ print_dpdk_version(void)
{
}
+bool
+dpdk_get_cpu_has_isa(const char *arch OVS_UNUSED,
+ const char *feature OVS_UNUSED)
+{
+ VLOG_ERR_ONCE("DPDK not supported in this version of Open vSwitch, "
+ "cannot use CPU flag based optimizations");
+ return false;
+}
+
void
dpdk_status(const struct ovsrec_open_vswitch *cfg)
{
@@ -22,6 +22,7 @@
#include <sys/stat.h>
#include <getopt.h>
+#include <rte_cpuflags.h>
#include <rte_errno.h>
#include <rte_log.h>
#include <rte_memzone.h>
@@ -513,6 +514,35 @@ print_dpdk_version(void)
puts(rte_version());
}
+#define CHECK_CPU_FEATURE(feature, name_str, RTE_CPUFLAG) \
+ do { \
+ if (strncmp(feature, name_str, strlen(name_str)) == 0) { \
+ int has_isa = rte_cpu_get_flag_enabled(RTE_CPUFLAG); \
+ VLOG_DBG("CPU flag %s, available %s\n", name_str, \
+ has_isa ? "yes" : "no"); \
+ return true; \
+ } \
+ } while (0)
+
+bool
+dpdk_get_cpu_has_isa(const char *arch, const char *feature)
+{
+ /* Ensure Arch is x86_64. */
+ if (strncmp(arch, "x86_64", 6) != 0) {
+ return false;
+ }
+
+#if __x86_64__
+ /* CPU flags only defined for the architecture that support it. */
+ CHECK_CPU_FEATURE(feature, "avx512f", RTE_CPUFLAG_AVX512F);
+ CHECK_CPU_FEATURE(feature, "bmi2", RTE_CPUFLAG_BMI2);
+#endif
+
+ VLOG_WARN("Unknown CPU arch,feature: %s,%s. Returning not supported.\n",
+ arch, feature);
+ return false;
+}
+
void
dpdk_status(const struct ovsrec_open_vswitch *cfg)
{
@@ -44,4 +44,6 @@ bool dpdk_per_port_memory(void);
bool dpdk_available(void);
void print_dpdk_version(void);
void dpdk_status(const struct ovsrec_open_vswitch *);
+bool dpdk_get_cpu_has_isa(const char *arch, const char *feature);
+
#endif /* dpdk.h */
This commit implements a method to retrieve the CPU ISA capabilities. These ISA capabilities can be used in OVS to at runtime select a function implementation to make the best use of the available ISA on the CPU. Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com> --- v7: - Add full stops to comments (Ian) v6: - Add #if around RTE_CPUFLAG_AVX512F as it is not defined on CPU architectures that don't support the ISA. This check fixes compilation on those CPUs, as previously it had an undefined RTE_CPUFLAG_* error. (Reported by Travis, thanks Ian & William for running checks) v5: - Change API to return bool, and return to true/false (William Tu) - Change error log to VLOG_ERR_ONCE instead of manual impl. (William Tu) v4: - Improve commit title and message --- lib/dpdk-stub.c | 9 +++++++++ lib/dpdk.c | 30 ++++++++++++++++++++++++++++++ lib/dpdk.h | 2 ++ 3 files changed, 41 insertions(+)