* [PATCH 1/2] libbpf: Use probe_name for legacy kprobe
@ 2021-12-25 8:32 Qiang Wang
2021-12-25 8:32 ` [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function Qiang Wang
2021-12-27 11:47 ` [PATCH 1/2] libbpf: Use probe_name for legacy kprobe Hengqi Chen
0 siblings, 2 replies; 5+ messages in thread
From: Qiang Wang @ 2021-12-25 8:32 UTC (permalink / raw)
To: ast, daniel, andrii, kafai, songliubraving, yhs, john.fastabend, kpsingh
Cc: netdev, bpf, linux-kernel, zhouchengming, songmuchun,
duanxiongchun, shekairui
Fix a bug in commit 46ed5fc33db9, which wrongly used the
func_name instead of probe_name to register legacy kprobe.
Fixes: 46ed5fc33db9 ("libbpf: Refactor and simplify legacy kprobe code")
Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Qiang Wang <wangqiang.wq.frank@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
---
tools/lib/bpf/libbpf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 7c74342bb668..b7d6c951fa09 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9735,7 +9735,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name),
func_name, offset);
- legacy_probe = strdup(func_name);
+ legacy_probe = strdup(probe_name);
if (!legacy_probe)
return libbpf_err_ptr(-ENOMEM);
--
2.20.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function
2021-12-25 8:32 [PATCH 1/2] libbpf: Use probe_name for legacy kprobe Qiang Wang
@ 2021-12-25 8:32 ` Qiang Wang
2021-12-27 11:39 ` Hengqi Chen
2021-12-27 12:08 ` kernel test robot
2021-12-27 11:47 ` [PATCH 1/2] libbpf: Use probe_name for legacy kprobe Hengqi Chen
1 sibling, 2 replies; 5+ messages in thread
From: Qiang Wang @ 2021-12-25 8:32 UTC (permalink / raw)
To: ast, daniel, andrii, kafai, songliubraving, yhs, john.fastabend, kpsingh
Cc: netdev, bpf, linux-kernel, zhouchengming, songmuchun,
duanxiongchun, shekairui
If repeated legacy kprobes on same function in one process,
libbpf will register using the same probe name and got -EBUSY
error. So append index to the probe name format to fix this
problem.
Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Qiang Wang <wangqiang.wq.frank@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
---
tools/lib/bpf/libbpf.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index b7d6c951fa09..0c41a45ffd54 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9634,7 +9634,9 @@ static int append_to_file(const char *file, const char *fmt, ...)
static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz,
const char *kfunc_name, size_t offset)
{
- snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), kfunc_name, offset);
+ static int index = 0;
+ snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset
+ __sync_fetch_and_add(&index, 1));
}
static int add_kprobe_event_legacy(const char *probe_name, bool retprobe,
--
2.20.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function
2021-12-25 8:32 ` [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function Qiang Wang
@ 2021-12-27 11:39 ` Hengqi Chen
2021-12-27 12:08 ` kernel test robot
1 sibling, 0 replies; 5+ messages in thread
From: Hengqi Chen @ 2021-12-27 11:39 UTC (permalink / raw)
To: Qiang Wang, ast, daniel, andrii, kafai, songliubraving, yhs,
john.fastabend, kpsingh
Cc: netdev, bpf, linux-kernel, zhouchengming, songmuchun,
duanxiongchun, shekairui
On 2021/12/25 4:32 PM, Qiang Wang wrote:
> If repeated legacy kprobes on same function in one process,
> libbpf will register using the same probe name and got -EBUSY
> error. So append index to the probe name format to fix this
> problem.
>
> Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
> Signed-off-by: Qiang Wang <wangqiang.wq.frank@bytedance.com>
> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
> ---
> tools/lib/bpf/libbpf.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index b7d6c951fa09..0c41a45ffd54 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -9634,7 +9634,9 @@ static int append_to_file(const char *file, const char *fmt, ...)
> static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz,
> const char *kfunc_name, size_t offset)
> {
> - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), kfunc_name, offset);
> + static int index = 0;
Add empty line after variable declaration.
> + snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset
Missing a comma after offset.
> + __sync_fetch_and_add(&index, 1));
> }
>
> static int add_kprobe_event_legacy(const char *probe_name, bool retprobe,
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/2] libbpf: Use probe_name for legacy kprobe
2021-12-25 8:32 [PATCH 1/2] libbpf: Use probe_name for legacy kprobe Qiang Wang
2021-12-25 8:32 ` [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function Qiang Wang
@ 2021-12-27 11:47 ` Hengqi Chen
1 sibling, 0 replies; 5+ messages in thread
From: Hengqi Chen @ 2021-12-27 11:47 UTC (permalink / raw)
To: Qiang Wang, ast, daniel, andrii, kafai, songliubraving, yhs,
john.fastabend, kpsingh
Cc: netdev, bpf, linux-kernel, zhouchengming, songmuchun,
duanxiongchun, shekairui
On 2021/12/25 4:32 PM, Qiang Wang wrote:
> Fix a bug in commit 46ed5fc33db9, which wrongly used the
> func_name instead of probe_name to register legacy kprobe.
>
> Fixes: 46ed5fc33db9 ("libbpf: Refactor and simplify legacy kprobe code")
> Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
> Signed-off-by: Qiang Wang <wangqiang.wq.frank@bytedance.com>
> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
> ---
> tools/lib/bpf/libbpf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 7c74342bb668..b7d6c951fa09 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -9735,7 +9735,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
> gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name),
> func_name, offset);
>
> - legacy_probe = strdup(func_name);
> + legacy_probe = strdup(probe_name);
> if (!legacy_probe)
> return libbpf_err_ptr(-ENOMEM);
>
Reviewed-by: Hengqi Chen <hengqi.chen@gmail.com>
Tested-by: Hengqi Chen <hengqi.chen@gmail.com>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function
2021-12-25 8:32 ` [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function Qiang Wang
2021-12-27 11:39 ` Hengqi Chen
@ 2021-12-27 12:08 ` kernel test robot
1 sibling, 0 replies; 5+ messages in thread
From: kernel test robot @ 2021-12-27 12:08 UTC (permalink / raw)
To: Qiang Wang, ast, daniel, andrii, kafai, songliubraving, yhs,
john.fastabend, kpsingh
Cc: llvm, kbuild-all, netdev, bpf
Hi Qiang,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on bpf-next/master]
[also build test ERROR on bpf/master horms-ipvs/master linus/master v5.16-rc7 next-20211224]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Qiang-Wang/libbpf-Use-probe_name-for-legacy-kprobe/20211225-163349
base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: i386-randconfig-c001-20211227 (https://download.01.org/0day-ci/archive/20211227/202112272030.W0PW9fN7-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 511726c64d3b6cca66f7c54d457d586aa3129f67)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/4a70a6c46086b85c64cae0b5c67980bd7f73cfeb
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Qiang-Wang/libbpf-Use-probe_name-for-legacy-kprobe/20211225-163349
git checkout 4a70a6c46086b85c64cae0b5c67980bd7f73cfeb
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
>> libbpf.c:9896:4: error: expected ')'
__sync_fetch_and_add(&index, 1));
^
libbpf.c:9895:10: note: to match this '('
snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset
^
1 error generated.
make[6]: *** [tools/build/Makefile.build:97: kernel/bpf/preload/libbpf/staticobjs/libbpf.o] Error 1
make[6]: Target '__build' not remade because of errors.
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-12-27 12:09 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2021-12-25 8:32 [PATCH 1/2] libbpf: Use probe_name for legacy kprobe Qiang Wang
2021-12-25 8:32 ` [PATCH 2/2] libbpf: Support repeated legacy kprobes on same function Qiang Wang
2021-12-27 11:39 ` Hengqi Chen
2021-12-27 12:08 ` kernel test robot
2021-12-27 11:47 ` [PATCH 1/2] libbpf: Use probe_name for legacy kprobe Hengqi Chen
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