linux/tools
Masami Hiramatsu 7cd5738d0d perf probe: Fall back to debuginfod query if debuginfo and source not found locally
Since 'perf probe' heavily depends on debuginfo, debuginfod gives us
many benefits on the 'perf probe' command on remote machine.

Especially, this will be helpful for the embedded devices which will not
have enough storage, or boot with a cross-build kernel whose source code
is in the host machine.

This will work as similar to commit c7a14fdcb3 ("perf build-ids:
Fall back to debuginfod query if debuginfo not found")

Tested with:

  (host) $ cd PATH/TO/KBUILD/DIR/
  (host) $ debuginfod -F .
  ...

  (remote) # perf probe -L vfs_read
  Failed to find the path for the kernel: No such file or directory
    Error: Failed to show lines.

  (remote) # export DEBUGINFOD_URLS="http://$HOST_IP:8002/"
  (remote) # perf probe -L vfs_read
  <vfs_read@...>
        0  ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
           {
        2         ssize_t ret;

                  if (!(file->f_mode & FMODE_READ))
                          return -EBADF;
        6         if (!(file->f_mode & FMODE_CAN_READ))
                          return -EINVAL;
        8         if (unlikely(!access_ok(buf, count)))
                          return -EFAULT;

       11         ret = rw_verify_area(READ, file, pos, count);
       12         if (ret)
                          return ret;
                  if (count > MAX_RW_COUNT)
  ...

  (remote) # perf probe -a "vfs_read count"
  Added new event:
    probe:vfs_read       (on vfs_read with count)

  (remote) # perf probe -l
    probe:vfs_read       (on vfs_read@ksrc/linux/fs/read_write.c with count)

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Frank Ch. Eigler <fche@redhat.com>
Cc: Aaron Merey <amerey@redhat.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Link: http://lore.kernel.org/lkml/160041610083.912668.13659563860278615846.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-18 09:20:47 -03:00
..
accounting
arch tools headers kvm s390: Sync headers with the kernel sources 2020-08-12 08:52:32 -03:00
bootconfig tools/bootconfig: Add testcases for value override operator 2020-08-03 16:22:29 -04:00
bpf tools/resolve_btfids: Fix sections with wrong alignment 2020-08-20 14:17:20 -07:00
build tools feature: Add missing -lzstd to the fast path feature detection 2020-09-09 11:11:01 -03:00
cgroup tools/cgroup: add memcg_slabinfo.py tool 2020-08-07 11:33:25 -07:00
debugging
edid
firewire
firmware
gpio tools: gpio: fix spurious close warning in gpio-event-mon 2020-07-12 10:22:01 +02:00
hv tools: hv: change http to https in hv_kvp_daemon.c 2020-07-06 10:46:23 +00:00
iio
include tools headers UAPI: update linux/in.h copy 2020-09-14 19:06:41 -03:00
io_uring io_uring: change the poll type to be 32-bits 2020-06-21 20:44:00 -06:00
kvm/kvm_stat
laptop
leds
lib libtraceevent: Fix build warning on 32-bit arches 2020-09-03 15:45:15 -03:00
memory-model These were the main changes in this cycle: 2020-08-03 14:39:35 -07:00
nfsd
objtool Misc updates: 2020-08-03 14:45:33 -07:00
pci
pcmcia
perf perf probe: Fall back to debuginfod query if debuginfo and source not found locally 2020-09-18 09:20:47 -03:00
power ACPI updates for 5.9-rc1 2020-08-03 20:37:22 -07:00
scripts
spi
testing linux-kselftest-5.9-rc5 2020-09-08 11:56:47 -07:00
thermal/tmon
time
usb tools: usb: move to tools buildsystem 2020-08-19 14:11:44 +02:00
virtio virtio: fixes, features 2020-08-11 14:34:17 -07:00
vm
wmi
Makefile bpf: Compile resolve_btfids tool at kernel compilation start 2020-07-13 10:42:02 -07:00