From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: pi3orama <pi3orama@163.com>
Cc: "Wangnan (F)" <wangnan0@huawei.com>,
He Kuang <hekuang@huawei.com>, Li Zefan <lizefan@huawei.com>,
Alexei Starovoitov <ast@plumgrid.com>,
Xia Kaixu <xiakaixu@huawei.com>,
linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
Jiri Olsa <jolsa@redhat.com>, David Ahern <dsahern@gmail.com>,
Namhyung Kim <namhyung@kernel.org>
Subject: Re: perf eBPF patch ordering. was: Re: perf test LLVM was: Re: [GIT PULL 00/39] perf tools: filtering events using eBPF programs
Date: Mon, 3 Aug 2015 16:49:17 -0300 [thread overview]
Message-ID: <20150803194917.GE5498@kernel.org> (raw)
In-Reply-To: <20150803161116.GB5498@kernel.org>
Em Mon, Aug 03, 2015 at 01:11:16PM -0300, Arnaldo Carvalho de Melo escreveu:
> > > ERROR: unable to compile ./foo.c
> > > Hint: Check error message shown above.
> > > LLVM 3.7 or newer is required. Which can be found from http://llvm.org
> > > You may want to try git trunk:
> > > git clone http://llvm.org/git/llvm.git
> > > and
<SNIP>
> > > or: perf record [<options>] -- <command> [<options>]
> > > -e, --event <event> event selector. use 'perf list' to list available events
> > > [root@felicio ~]#
> > > Now to find a hello.c BPF scriptlet...
So, we do not need to provide all this LLVM environment installation
hints when we get to any error, i.e. the one above was just becasuse
"./foo.c" doesn't exist, clang ran successfully, so no need for telling
the user how to install it.
The following error also shouldn't emit those hints:
[root@felicio ~]# perf record -e ./lock_page.bpf.c sleep 1
/root/./lock_page.bpf.c:1:5: error: expected parameter declarator
SEC("lock_page=__lock_page page->flags")
^
/root/./lock_page.bpf.c:1:5: error: expected ')'
/root/./lock_page.bpf.c:1:4: note: to match this '('
SEC("lock_page=__lock_page page->flags")
^
/root/./lock_page.bpf.c:1:1: warning: type specifier missing, defaults to 'int' [-Wimplicit-int]
SEC("lock_page=__lock_page page->flags")
^
/root/./lock_page.bpf.c:1:41: error: expected ';' after top level declarator
SEC("lock_page=__lock_page page->flags")
^
;
/root/./lock_page.bpf.c:2:22: warning: declaration of 'struct pt_regs' will not be visible outside of this function [-Wvisibility]
int lock_page(struct pt_regs *ctx, int err, unsigned long flags)
^
2 warnings and 3 errors generated.
ERROR: unable to compile ./lock_page.bpf.c
Hint: Check error message shown above.
LLVM 3.7 or newer is required. Which can be found from http://llvm.org
You may want to try git trunk:
git clone http://llvm.org/git/llvm.git
and
git clone http://llvm.org/git/clang.git
Or fetch the latest clang/llvm 3.7 from pre-built llvm packages for
debian/ubuntu:
http://llvm.org/apt
If you are using old version of clang, change 'clang-bpf-cmd-template'
option in [llvm] section of ~/.perfconfig to:
"$CLANG_EXEC $CLANG_OPTIONS $KERNEL_INC_OPTIONS \
-working-directory $WORKING_DIR -c $CLANG_SOURCE \
-emit-llvm -o - | /path/to/llc -march=bpf -filetype=obj -o -"
(Replace /path/to/llc with path to your llc)
Hint: You can also pre-compile it into .o
invalid or unsupported event: './lock_page.bpf.c'
Run 'perf list' for a list of valid events
usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-e, --event <event> event selector. use 'perf list' to list available events
[root@felicio ~]#
And I am interested in that "Hint: You can also pre-compile it into .o", seems
like a useful one, if it was on the screen, i.e. how can I pre-compile this
into a .o, its some random piece of eBPF "scriptlet" I found in one of your
csets, after this cset in your patchkit:
[root@felicio ~]# cat lock_page.bpf.c
SEC("lock_page=__lock_page page->flags")
int lock_page(struct pt_regs *ctx, int err, unsigned long flags)
{
return 1;
}
[root@felicio ~]#
Also it would be nice to tell the user, when compilation fails, where to look
for a eBPF scriptlet primer, i.e. where can I find some documentation on how
to write such scriptlets?
At this point I expect it to build the .c into a .o, then, as the wiring up is
not there, tell the user that all went well, but more infrastructure is needed,
apply the following patches from Wang Nan! 8-)
- Arnaldo
next prev parent reply other threads:[~2015-08-03 19:49 UTC|newest]
Thread overview: 78+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-09 12:35 [GIT PULL 00/39] perf tools: filtering events using eBPF programs Wang Nan
2015-07-09 12:35 ` [PATCH 01/39] bpf tools: Collect symbol table from SHT_SYMTAB section Wang Nan
2015-07-09 12:35 ` [PATCH 02/39] bpf tools: Collect eBPF programs from their own sections Wang Nan
2015-07-09 15:58 ` Arnaldo Carvalho de Melo
2015-07-10 3:07 ` Wangnan (F)
2015-07-13 19:51 ` Arnaldo Carvalho de Melo
2015-07-14 3:58 ` Wangnan (F)
2015-07-09 12:35 ` [PATCH 03/39] bpf tools: Collect relocation sections from SHT_REL sections Wang Nan
2015-07-09 12:35 ` [PATCH 04/39] bpf tools: Record map accessing instructions for each program Wang Nan
2015-07-09 12:35 ` [PATCH 05/39] bpf tools: Add bpf.c/h for common bpf operations Wang Nan
2015-07-09 12:35 ` [PATCH 06/39] bpf tools: Create eBPF maps defined in an object file Wang Nan
2015-07-13 19:54 ` Arnaldo Carvalho de Melo
2015-07-14 3:59 ` Wangnan (F)
2015-07-09 12:35 ` [PATCH 07/39] bpf tools: Relocate eBPF programs Wang Nan
2015-07-09 12:35 ` [PATCH 08/39] bpf tools: Introduce bpf_load_program() to bpf.c Wang Nan
2015-07-09 12:35 ` [PATCH 09/39] bpf tools: Load eBPF programs in object files into kernel Wang Nan
2015-07-09 12:35 ` [PATCH 10/39] bpf tools: Introduce accessors for struct bpf_program Wang Nan
2015-07-09 12:35 ` [PATCH 11/39] bpf tools: Link all bpf objects onto a list Wang Nan
2015-07-09 12:35 ` [PATCH 12/39] perf tools: Introduce llvm config options Wang Nan
2015-07-21 11:13 ` [PATCH 12/39 update] " Wang Nan
2015-08-08 8:16 ` [tip:perf/core] " tip-bot for Wang Nan
2015-07-09 12:35 ` [PATCH 13/39] perf tools: Call clang to compile C source to object code Wang Nan
2015-07-09 12:35 ` [PATCH 14/39] perf tools: Auto detecting kernel build directory Wang Nan
2015-07-13 21:46 ` Arnaldo Carvalho de Melo
2015-07-14 6:56 ` Wangnan (F)
2015-07-14 7:16 ` Wangnan (F)
2015-07-09 12:35 ` [PATCH 15/39] perf tools: Auto detecting kernel include options Wang Nan
2015-08-08 8:17 ` [tip:perf/core] " tip-bot for Wang Nan
2015-07-09 12:35 ` [PATCH 16/39] perf tests: Add LLVM test for eBPF on-the-fly compiling Wang Nan
2015-07-15 10:54 ` [PATCH updated " Wang Nan
2015-07-22 4:46 ` [PATCH 16/39 RESEND] " Wang Nan
2015-07-09 12:35 ` [PATCH 17/39] perf tools: Make perf depend on libbpf Wang Nan
2015-07-09 12:35 ` [PATCH 18/39] perf record: Enable passing bpf object file to --event Wang Nan
2015-07-09 12:35 ` [PATCH 19/39] perf record: Compile scriptlets if pass '.c' " Wang Nan
2015-07-09 12:35 ` [PATCH 20/39] perf tools: Parse probe points of eBPF programs during preparation Wang Nan
2015-07-09 12:35 ` [PATCH 21/39] perf probe: Attach trace_probe_event with perf_probe_event Wang Nan
2015-07-09 12:35 ` [PATCH 22/39] perf record: Probe at kprobe points Wang Nan
2015-07-09 12:35 ` [PATCH 23/39] perf record: Load all eBPF object into kernel Wang Nan
2015-07-09 12:35 ` [PATCH 24/39] perf tools: Add bpf_fd field to evsel and config it Wang Nan
2015-07-09 12:35 ` [PATCH 25/39] perf tools: Attach eBPF program to perf event Wang Nan
2015-07-09 12:35 ` [PATCH 26/39] perf tools: Suppress probing messages when probing by BPF loading Wang Nan
2015-07-09 12:35 ` [PATCH 27/39] perf record: Add clang options for compiling BPF scripts Wang Nan
2015-07-09 12:35 ` [PATCH 28/39] bpf tools: Load a program with different instances using preprocessor Wang Nan
2015-07-13 5:44 ` Wangnan (F)
2015-07-09 12:35 ` [PATCH 29/39] perf tools: Fix probe-event.h include Wang Nan
2015-07-09 12:35 ` [PATCH 30/39] perf probe: Reset args and nargs for probe_trace_event when failure Wang Nan
2015-07-09 12:35 ` [PATCH 31/39] perf tools: Move linux/filter.h to tools/include Wang Nan
2015-07-09 12:35 ` [PATCH 32/39] perf tools: Add BPF_PROLOGUE config options for further patches Wang Nan
2015-07-09 12:35 ` [PATCH 33/39] perf tools: Introduce arch_get_reg_info() for x86 Wang Nan
2015-07-09 12:35 ` [PATCH 34/39] perf tools: Add prologue for BPF programs for fetching arguments Wang Nan
2015-07-09 12:35 ` [PATCH 35/39] perf tools: Generate prologue for BPF programs Wang Nan
2015-07-09 12:35 ` [PATCH 36/39] perf tools: Use same BPF program if arguments are identical Wang Nan
2015-07-09 12:35 ` [PATCH 37/39] perf record: Support custom vmlinux path Wang Nan
2015-07-09 12:35 ` [PATCH 38/39] perf probe: Init symbol as kprobe if any event is kprobe Wang Nan
2015-07-09 12:35 ` [PATCH 39/39] perf tools: Support attach BPF program on uprobe events Wang Nan
2015-07-14 15:36 ` perf test LLVM was: Re: [GIT PULL 00/39] perf tools: filtering events using eBPF programs Arnaldo Carvalho de Melo
2015-07-15 10:49 ` Wangnan (F)
2015-07-15 11:20 ` Arnaldo Carvalho de Melo
2015-07-17 2:34 ` Wangnan (F)
[not found] ` <CA+JHD93=ZMFP0gB1NqTXGBjTfSyYC-53Uj7r11gQJnKtQRKcDg@mail.gmail.com>
2015-07-21 11:09 ` Wangnan (F)
2015-07-21 11:41 ` Arnaldo Carvalho de Melo
2015-07-22 4:40 ` Wangnan (F)
2015-07-31 15:35 ` perf eBPF patch ordering. was: " Arnaldo Carvalho de Melo
2015-07-31 20:31 ` Arnaldo Carvalho de Melo
2015-08-03 2:37 ` Wangnan (F)
2015-08-03 15:07 ` Arnaldo Carvalho de Melo
2015-08-03 15:19 ` Arnaldo Carvalho de Melo
2015-08-03 15:53 ` pi3orama
2015-08-03 16:11 ` Arnaldo Carvalho de Melo
2015-08-03 19:49 ` Arnaldo Carvalho de Melo [this message]
2015-08-04 5:28 ` Wangnan (F)
2015-08-04 10:39 ` Wangnan (F)
2015-08-04 15:55 ` Arnaldo Carvalho de Melo
2015-08-04 16:11 ` Arnaldo Carvalho de Melo
2015-08-04 16:13 ` pi3orama
2015-08-06 1:44 ` Wangnan (F)
2015-08-06 14:46 ` Arnaldo Carvalho de Melo
2015-08-06 15:58 ` Arnaldo Carvalho de Melo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20150803194917.GE5498@kernel.org \
--to=acme@kernel.org \
--cc=ast@plumgrid.com \
--cc=dsahern@gmail.com \
--cc=hekuang@huawei.com \
--cc=jolsa@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=lizefan@huawei.com \
--cc=mingo@kernel.org \
--cc=namhyung@kernel.org \
--cc=pi3orama@163.com \
--cc=wangnan0@huawei.com \
--cc=xiakaixu@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.