commit 023154c7708087ddf6c2031cef5d25c2445b70c4
author Sumanth Korikkar <sumanthk@linux.ibm.com> Mon Apr 20 05:54:57 2020 -0500
committer Sumanth Korikkar <sumanthk@linux.ibm.com> Thu Apr 23 01:36:18 2020 -0500
tree 6985039cb187a94895d43f0e46bcae87cf26aae0
parent ac157b474b2e2964ec2cba81574f2bddbd62b42b

bcc/tools: Introduce bpf_probe_read_user to the tools.

This is essential for architecture which do have overlapping address space.
- bpf_probe_read_kernel() shall be used for reading data from kernel space
to the bpf vm.
- bpf_probe_read_user() shall be used for reading data from user space
  to the bpf vm.

Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>

tools/lib/ucalls.py

diff --git a/tools/lib/ucalls.py b/tools/lib/ucalls.py
index 307df25..396d56e 100755
--- a/tools/lib/ucalls.py
+++ b/tools/lib/ucalls.py
@@ -158,9 +158,9 @@
 #endif
     READ_CLASS
     READ_METHOD
-    bpf_probe_read(&data.method.clazz, sizeof(data.method.clazz),
+    bpf_probe_read_user(&data.method.clazz, sizeof(data.method.clazz),
                    (void *)clazz);
-    bpf_probe_read(&data.method.method, sizeof(data.method.method),
+    bpf_probe_read_user(&data.method.method, sizeof(data.method.method),
                    (void *)method);
 #ifndef LATENCY
     valp = counts.lookup_or_try_init(&data.method, &val);
@@ -182,9 +182,9 @@
     data.pid = bpf_get_current_pid_tgid();
     READ_CLASS
     READ_METHOD
-    bpf_probe_read(&data.method.clazz, sizeof(data.method.clazz),
+    bpf_probe_read_user(&data.method.clazz, sizeof(data.method.clazz),
                    (void *)clazz);
-    bpf_probe_read(&data.method.method, sizeof(data.method.method),
+    bpf_probe_read_user(&data.method.method, sizeof(data.method.method),
                    (void *)method);
     entry_timestamp = entry.lookup(&data);
     if (!entry_timestamp) {