1. 25 1月, 2018 27 次提交
  2. 23 1月, 2018 9 次提交
  3. 19 1月, 2018 1 次提交
    • A
      perf bpf: Don't warn about unavailability of builtin clang, just fallback · 87252323
      Arnaldo Carvalho de Melo 提交于
      When clang is not linked with 'perf' we should just add a debug message
      about that before doing the fallback to calling the external compiler.
      
      I.e. just the "-95" warning below gets turned into a debug message:
      
        # cat sys_enter_open.c
        #include "bpf.h"
      
        SEC("syscalls:sys_enter_open")
        int func(void *ctx)
        {
      	struct {
      		char *ptr;
      		char path[256];
      	} filename = {
      		.ptr = *((char **)(ctx + 16)),
      	};
      	int len = bpf_probe_read_str(filename.path, sizeof(filename.path), filename.ptr);
      	if (len > 0) {
      		if (len == 1)
      			perf_event_output(ctx, &__bpf_stdout__, BPF_F_CURRENT_CPU, &filename, len + sizeof(filename.ptr));
      		else if (len < 256)
      			perf_event_output(ctx, &__bpf_stdout__, BPF_F_CURRENT_CPU, &filename, len + sizeof(filename.ptr));
              }
      	return 0;
        }
        # trace -e open,sys_enter_open.c
        bpf: builtin compilation failed: -95, try external compiler
           0.000 (         ): __bpf_stdout__:@......./proc/self/task/11160/comm..)
           0.014 ( 0.116 ms): qemu-system-x8/6721 open(filename: /proc/self/task/11160/comm, flags: RDWR) = 91
        2335.411 (         ): __bpf_stdout__:FB..~.../etc/resolv.conf....)
        2335.421 ( 0.030 ms): chronyd/883 open(filename: /etc/resolv.conf, flags: CLOEXEC) = 5
      ^C#
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Wang Nan <wangnan0@huawei.com>
      Link: https://lkml.kernel.org/n/tip-z5aak9oay448ffj37giz94yr@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      87252323
  4. 18 1月, 2018 3 次提交