Message ID | 152992950237.15897.9894201421576854943.stgit@alrua-kau |
---|---|
State | Accepted, archived |
Delegated to: | BPF Maintainers |
Headers | show |
Series | [RESEND,bpf-next,v6,1/2] trace_helpers.c: Add helpers to poll multiple perf FDs for events | expand |
On Mon, Jun 25, 2018 at 5:25 AM, Toke Høiland-Jørgensen <toke@toke.dk> wrote: > Add two new helper functions to trace_helpers that supports polling > multiple perf file descriptors for events. These are used to the XDP > perf_event_output example, which needs to work with one perf fd per CPU. > > Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> > Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Acked-by: Song Liu <songliubraving@fb.com> > --- > tools/testing/selftests/bpf/trace_helpers.c | 48 ++++++++++++++++++++++++++- > tools/testing/selftests/bpf/trace_helpers.h | 4 ++ > 2 files changed, 50 insertions(+), 2 deletions(-) > > diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c > index 3868dcb63420..cabe2a3a3b30 100644 > --- a/tools/testing/selftests/bpf/trace_helpers.c > +++ b/tools/testing/selftests/bpf/trace_helpers.c > @@ -88,7 +88,7 @@ static int page_size; > static int page_cnt = 8; > static struct perf_event_mmap_page *header; > > -int perf_event_mmap(int fd) > +int perf_event_mmap_header(int fd, struct perf_event_mmap_page **header) > { > void *base; > int mmap_size; > @@ -102,10 +102,15 @@ int perf_event_mmap(int fd) > return -1; > } > > - header = base; > + *header = base; > return 0; > } > > +int perf_event_mmap(int fd) > +{ > + return perf_event_mmap_header(fd, &header); > +} > + > static int perf_event_poll(int fd) > { > struct pollfd pfd = { .fd = fd, .events = POLLIN }; > @@ -163,3 +168,42 @@ int perf_event_poller(int fd, perf_event_print_fn output_fn) > > return ret; > } > + > +int perf_event_poller_multi(int *fds, struct perf_event_mmap_page **headers, > + int num_fds, perf_event_print_fn output_fn) > +{ > + enum bpf_perf_event_ret ret; > + struct pollfd *pfds; > + void *buf = NULL; > + size_t len = 0; > + int i; > + > + pfds = calloc(num_fds, sizeof(*pfds)); > + if (!pfds) > + return LIBBPF_PERF_EVENT_ERROR; > + > + for (i = 0; i < num_fds; i++) { > + pfds[i].fd = fds[i]; > + pfds[i].events = POLLIN; > + } > + > + for (;;) { > + poll(pfds, num_fds, 1000); > + for (i = 0; i < num_fds; i++) { > + if (!pfds[i].revents) > + continue; > + > + ret = bpf_perf_event_read_simple(headers[i], > + page_cnt * page_size, > + page_size, &buf, &len, > + bpf_perf_event_print, > + output_fn); > + if (ret != LIBBPF_PERF_EVENT_CONT) > + break; > + } > + } > + free(buf); > + free(pfds); > + > + return ret; > +} > diff --git a/tools/testing/selftests/bpf/trace_helpers.h b/tools/testing/selftests/bpf/trace_helpers.h > index 3b4bcf7f5084..18924f23db1b 100644 > --- a/tools/testing/selftests/bpf/trace_helpers.h > +++ b/tools/testing/selftests/bpf/trace_helpers.h > @@ -3,6 +3,7 @@ > #define __TRACE_HELPER_H > > #include <libbpf.h> > +#include <linux/perf_event.h> > > struct ksym { > long addr; > @@ -16,6 +17,9 @@ long ksym_get_addr(const char *name); > typedef enum bpf_perf_event_ret (*perf_event_print_fn)(void *data, int size); > > int perf_event_mmap(int fd); > +int perf_event_mmap_header(int fd, struct perf_event_mmap_page **header); > /* return LIBBPF_PERF_EVENT_DONE or LIBBPF_PERF_EVENT_ERROR */ > int perf_event_poller(int fd, perf_event_print_fn output_fn); > +int perf_event_poller_multi(int *fds, struct perf_event_mmap_page **headers, > + int num_fds, perf_event_print_fn output_fn); > #endif >
On 06/25/2018 02:25 PM, Toke Høiland-Jørgensen wrote: > Add two new helper functions to trace_helpers that supports polling > multiple perf file descriptors for events. These are used to the XDP > perf_event_output example, which needs to work with one perf fd per CPU. > > Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> > Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Both applied to bpf-next, thanks Toke!
diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c index 3868dcb63420..cabe2a3a3b30 100644 --- a/tools/testing/selftests/bpf/trace_helpers.c +++ b/tools/testing/selftests/bpf/trace_helpers.c @@ -88,7 +88,7 @@ static int page_size; static int page_cnt = 8; static struct perf_event_mmap_page *header; -int perf_event_mmap(int fd) +int perf_event_mmap_header(int fd, struct perf_event_mmap_page **header) { void *base; int mmap_size; @@ -102,10 +102,15 @@ int perf_event_mmap(int fd) return -1; } - header = base; + *header = base; return 0; } +int perf_event_mmap(int fd) +{ + return perf_event_mmap_header(fd, &header); +} + static int perf_event_poll(int fd) { struct pollfd pfd = { .fd = fd, .events = POLLIN }; @@ -163,3 +168,42 @@ int perf_event_poller(int fd, perf_event_print_fn output_fn) return ret; } + +int perf_event_poller_multi(int *fds, struct perf_event_mmap_page **headers, + int num_fds, perf_event_print_fn output_fn) +{ + enum bpf_perf_event_ret ret; + struct pollfd *pfds; + void *buf = NULL; + size_t len = 0; + int i; + + pfds = calloc(num_fds, sizeof(*pfds)); + if (!pfds) + return LIBBPF_PERF_EVENT_ERROR; + + for (i = 0; i < num_fds; i++) { + pfds[i].fd = fds[i]; + pfds[i].events = POLLIN; + } + + for (;;) { + poll(pfds, num_fds, 1000); + for (i = 0; i < num_fds; i++) { + if (!pfds[i].revents) + continue; + + ret = bpf_perf_event_read_simple(headers[i], + page_cnt * page_size, + page_size, &buf, &len, + bpf_perf_event_print, + output_fn); + if (ret != LIBBPF_PERF_EVENT_CONT) + break; + } + } + free(buf); + free(pfds); + + return ret; +} diff --git a/tools/testing/selftests/bpf/trace_helpers.h b/tools/testing/selftests/bpf/trace_helpers.h index 3b4bcf7f5084..18924f23db1b 100644 --- a/tools/testing/selftests/bpf/trace_helpers.h +++ b/tools/testing/selftests/bpf/trace_helpers.h @@ -3,6 +3,7 @@ #define __TRACE_HELPER_H #include <libbpf.h> +#include <linux/perf_event.h> struct ksym { long addr; @@ -16,6 +17,9 @@ long ksym_get_addr(const char *name); typedef enum bpf_perf_event_ret (*perf_event_print_fn)(void *data, int size); int perf_event_mmap(int fd); +int perf_event_mmap_header(int fd, struct perf_event_mmap_page **header); /* return LIBBPF_PERF_EVENT_DONE or LIBBPF_PERF_EVENT_ERROR */ int perf_event_poller(int fd, perf_event_print_fn output_fn); +int perf_event_poller_multi(int *fds, struct perf_event_mmap_page **headers, + int num_fds, perf_event_print_fn output_fn); #endif