Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1215619

Re: [PATCH 31/32] tools lib traceevent: Support function __get_dynamic_array_len

From Alexei Starovoitov <ast@plumgrid.com>
Newsgroups linux.kernel
Subject Re: [PATCH 31/32] tools lib traceevent: Support function __get_dynamic_array_len
Date 2015-08-29 02:30 +0200
Message-ID <q2CbU-2nr-1@gated-at.bofh.it> (permalink)
References <q2lXr-4sW-3@gated-at.bofh.it> <q2lXt-4sW-35@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On 8/28/15 12:06 AM, Wang Nan wrote:
> From: He Kuang<hekuang@huawei.com>
>
> Support helper function __get_dynamic_array_len() in libtraceevent,
> this function is used accompany with __print_array() or __print_hex(),
> but currently it is not an available function in the function list of
> process_function().
>
> The total allocated length of the dynamic array is embedded in the top
> half of __data_loc_##item field. This patch adds new arg type
> PRINT_DYNAMIC_ARRAY_LEN to return the length to eval_num_arg(),
>
> Signed-off-by: He Kuang<hekuang@huawei.com>
> Acked-by: Namhyung Kim<namhyung@kernel.org>

Tested-by: Alexei Starovoitov <ast@plumgrid.com>

this patch fixes the perf crash:
   Warning: [bpf:bpf_output_data] function __get_dynamic_array_len not 
defined
   Warning: Error: expected type 5 but read 0
*** glibc detected *** perf_4.2.0: double free or corruption (fasttop): 
0x00000000032caf20 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x7ec96)[0x7f0d5d2d3c96]

it's not strictly necessary until patch 32 lands, but I think it's
a good fix regardless.
Steven, could you take it into your tree?

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Find similar | Unroll thread


Thread

[PATCH 31/32] tools lib traceevent: Support function __get_dynamic_array_len Wang Nan <wangnan0@huawei.com> - 2015-08-28 09:10 +0200
  Re: [PATCH 31/32] tools lib traceevent: Support function  __get_dynamic_array_len Alexei Starovoitov <ast@plumgrid.com> - 2015-08-29 02:30 +0200

csiph-web