bpf: Update descriptions for helpers bpf_get_func_arg[_cnt]()

Now instead of the number of arguments, the number of registers
holding argument values are stored in trampoline. Update
the description of bpf_get_func_arg[_cnt]() helpers. Previous
programs without struct arguments should continue to work
as usual.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220831152657.2078805-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Yonghong Song 2022-08-31 08:26:57 -07:00 committed by Alexei Starovoitov
parent a9c5ad31fb
commit 27ed9353ae
2 changed files with 10 additions and 8 deletions

View File

@ -5079,12 +5079,12 @@ union bpf_attr {
*
* long bpf_get_func_arg(void *ctx, u32 n, u64 *value)
* Description
* Get **n**-th argument (zero based) of the traced function (for tracing programs)
* Get **n**-th argument register (zero based) of the traced function (for tracing programs)
* returned in **value**.
*
* Return
* 0 on success.
* **-EINVAL** if n >= arguments count of traced function.
* **-EINVAL** if n >= argument register count of traced function.
*
* long bpf_get_func_ret(void *ctx, u64 *value)
* Description
@ -5097,10 +5097,11 @@ union bpf_attr {
*
* long bpf_get_func_arg_cnt(void *ctx)
* Description
* Get number of arguments of the traced function (for tracing programs).
* Get number of registers of the traced function (for tracing programs) where
* function arguments are stored in these registers.
*
* Return
* The number of arguments of the traced function.
* The number of argument registers of the traced function.
*
* int bpf_get_retval(void)
* Description

View File

@ -5079,12 +5079,12 @@ union bpf_attr {
*
* long bpf_get_func_arg(void *ctx, u32 n, u64 *value)
* Description
* Get **n**-th argument (zero based) of the traced function (for tracing programs)
* Get **n**-th argument register (zero based) of the traced function (for tracing programs)
* returned in **value**.
*
* Return
* 0 on success.
* **-EINVAL** if n >= arguments count of traced function.
* **-EINVAL** if n >= argument register count of traced function.
*
* long bpf_get_func_ret(void *ctx, u64 *value)
* Description
@ -5097,10 +5097,11 @@ union bpf_attr {
*
* long bpf_get_func_arg_cnt(void *ctx)
* Description
* Get number of arguments of the traced function (for tracing programs).
* Get number of registers of the traced function (for tracing programs) where
* function arguments are stored in these registers.
*
* Return
* The number of arguments of the traced function.
* The number of argument registers of the traced function.
*
* int bpf_get_retval(void)
* Description