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author | Yonghong Song <yhs@fb.com> | 2018-04-28 22:28:13 -0700 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2018-04-29 08:45:54 -0700 |
commit | 28dbf861deacb0321604bf1c5e1ccc34dd215669 (patch) | |
tree | ae98045b9d24ea60e1034b08200d74e762dde8bb /samples/bpf/trace_output_user.c | |
parent | de2ff05f48afcde816ff4edb217417f62f624ab5 (diff) | |
download | linux-28dbf861deacb0321604bf1c5e1ccc34dd215669.tar.gz linux-28dbf861deacb0321604bf1c5e1ccc34dd215669.tar.bz2 linux-28dbf861deacb0321604bf1c5e1ccc34dd215669.zip |
samples/bpf: move common-purpose trace functions to selftests
There is no functionality change in this patch. The common-purpose
trace functions, including perf_event polling and ksym lookup,
are moved from trace_output_user.c and bpf_load.c to
selftests/bpf/trace_helpers.c so that these function can
be reused later in selftests.
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'samples/bpf/trace_output_user.c')
-rw-r--r-- | samples/bpf/trace_output_user.c | 110 |
1 files changed, 10 insertions, 100 deletions
diff --git a/samples/bpf/trace_output_user.c b/samples/bpf/trace_output_user.c index ccca1e348017..5e78c2ecd08d 100644 --- a/samples/bpf/trace_output_user.c +++ b/samples/bpf/trace_output_user.c @@ -21,100 +21,10 @@ #include "libbpf.h" #include "bpf_load.h" #include "perf-sys.h" +#include "trace_helpers.h" static int pmu_fd; -int page_size; -int page_cnt = 8; -volatile struct perf_event_mmap_page *header; - -typedef void (*print_fn)(void *data, int size); - -static int perf_event_mmap(int fd) -{ - void *base; - int mmap_size; - - page_size = getpagesize(); - mmap_size = page_size * (page_cnt + 1); - - base = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); - if (base == MAP_FAILED) { - printf("mmap err\n"); - return -1; - } - - header = base; - return 0; -} - -static int perf_event_poll(int fd) -{ - struct pollfd pfd = { .fd = fd, .events = POLLIN }; - - return poll(&pfd, 1, 1000); -} - -struct perf_event_sample { - struct perf_event_header header; - __u32 size; - char data[]; -}; - -static void perf_event_read(print_fn fn) -{ - __u64 data_tail = header->data_tail; - __u64 data_head = header->data_head; - __u64 buffer_size = page_cnt * page_size; - void *base, *begin, *end; - char buf[256]; - - asm volatile("" ::: "memory"); /* in real code it should be smp_rmb() */ - if (data_head == data_tail) - return; - - base = ((char *)header) + page_size; - - begin = base + data_tail % buffer_size; - end = base + data_head % buffer_size; - - while (begin != end) { - struct perf_event_sample *e; - - e = begin; - if (begin + e->header.size > base + buffer_size) { - long len = base + buffer_size - begin; - - assert(len < e->header.size); - memcpy(buf, begin, len); - memcpy(buf + len, base, e->header.size - len); - e = (void *) buf; - begin = base + e->header.size - len; - } else if (begin + e->header.size == base + buffer_size) { - begin = base; - } else { - begin += e->header.size; - } - - if (e->header.type == PERF_RECORD_SAMPLE) { - fn(e->data, e->size); - } else if (e->header.type == PERF_RECORD_LOST) { - struct { - struct perf_event_header header; - __u64 id; - __u64 lost; - } *lost = (void *) e; - printf("lost %lld events\n", lost->lost); - } else { - printf("unknown event type=%d size=%d\n", - e->header.type, e->header.size); - } - } - - __sync_synchronize(); /* smp_mb() */ - header->data_tail = data_head; -} - static __u64 time_get_ns(void) { struct timespec ts; @@ -127,7 +37,7 @@ static __u64 start_time; #define MAX_CNT 100000ll -static void print_bpf_output(void *data, int size) +static int print_bpf_output(void *data, int size) { static __u64 cnt; struct { @@ -138,7 +48,7 @@ static void print_bpf_output(void *data, int size) if (e->cookie != 0x12345678) { printf("BUG pid %llx cookie %llx sized %d\n", e->pid, e->cookie, size); - kill(0, SIGINT); + return PERF_EVENT_ERROR; } cnt++; @@ -146,8 +56,10 @@ static void print_bpf_output(void *data, int size) if (cnt == MAX_CNT) { printf("recv %lld events per sec\n", MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); - kill(0, SIGINT); + return PERF_EVENT_DONE; } + + return PERF_EVENT_CONT; } static void test_bpf_perf_event(void) @@ -170,6 +82,7 @@ int main(int argc, char **argv) { char filename[256]; FILE *f; + int ret; snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); @@ -187,10 +100,7 @@ int main(int argc, char **argv) (void) f; start_time = time_get_ns(); - for (;;) { - perf_event_poll(pmu_fd); - perf_event_read(print_bpf_output); - } - - return 0; + ret = perf_event_poller(pmu_fd, print_bpf_output); + kill(0, SIGINT); + return ret; } |