linux/tools
Arnaldo Carvalho de Melo 6a648b534d perf trace: Associate vfs_getname()'ed pathname with fd returned from 'openat'
When the vfs_getname() wannabe tracepoint is in place:

  # perf probe -l
    probe:vfs_getname    (on getname_flags:73@acme/git/linux/fs/namei.c with pathname)
  #

'perf trace' will use it to get the pathname when it is copied from
userspace to the kernel, right after syscalls:sys_enter_open, copied
in the 'probe:vfs_getname', stash it somewhere and then, at
syscalls:sys_exit_open time, if the 'open' return is not -1, i.e. a
successfull open syscall, associate that pathname to this return, i.e.
the fd.

We were not doing this for the 'openat' syscall, which would cause 'perf
trace' to fallback to using /proc to get the fd, change it so that we
use what we got from probe:vfs_getname, reducing the 'openat'
beautification process cost, ditching the syscalls performed to read
procfs state and avoiding some possible races in the process.

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-xnp44ao3bkb6ejeczxfnjwsh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-02 10:30:08 -03:00
..
accounting
arch Merge remote-tracking branch 'tip/perf/urgent' into perf/core 2018-07-31 09:55:45 -03:00
bpf tools/bpftool: Fix segfault case regarding 'pin' arguments 2018-07-20 10:16:54 +02:00
build tools: build: Use HOSTLDFLAGS with fixdep 2018-07-13 00:48:18 +09:00
cgroup tools: fix cross-compile var clobbering 2018-02-21 15:35:42 -08:00
firewire
gpio Linux 4.16-rc5 2018-03-18 17:48:59 +01:00
hv tools: hv: include string.h in hv_fcopy_daemon 2018-03-06 09:57:16 -08:00
iio tools: iio: iio_generic_buffer: allow continuous looping 2018-05-20 14:55:58 +01:00
include tools include uapi: Grab a copy of linux/in.h 2018-07-31 10:52:37 -03:00
kvm/kvm_stat tools/kvm_stat: Remove unused function 2018-03-28 22:47:06 +02:00
laptop tools: fix cross-compile var clobbering 2018-02-21 15:35:42 -08:00
leds tools: fix cross-compile var clobbering 2018-02-21 15:35:42 -08:00
lib docs: Fix some broken references 2018-06-15 18:10:01 -03:00
memory-model tools/memory-model: Add reference for 'Simplifying ARM concurrency' 2018-05-15 08:11:19 +02:00
nfsd
objtool objtool: Use '.strtab' if '.shstrtab' doesn't exist, to support ORC tables on Clang 2018-07-14 14:59:42 +02:00
pci
pcmcia
perf perf trace: Associate vfs_getname()'ed pathname with fd returned from 'openat' 2018-08-02 10:30:08 -03:00
power Merge branch 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2018-06-21 00:37:04 +02:00
scripts Kbuild: fix # escaping in .cmd files for future Make 2018-04-11 00:03:02 +09:00
spi tools: fix cross-compile var clobbering 2018-02-21 15:35:42 -08:00
testing Various fixes to the tracing infrastructure: 2018-07-27 09:50:33 -07:00
thermal/tmon tools/thermal: tmon: fix for segfault 2018-03-27 09:51:23 +02:00
time
usb tools: usb: ffs-test: Fix build on big endian systems 2018-07-17 10:12:51 +03:00
virtio sg: remove ->sg_magic member 2018-06-29 08:48:06 -06:00
vm mm: mark pages in use for page tables 2018-06-07 17:34:37 -07:00
wmi tools: fix cross-compile var clobbering 2018-02-21 15:35:42 -08:00
Makefile platform-drivers-x86 for v4.15-1 2017-11-18 10:26:57 -08:00