libbpf: Minor style improvements in USDT code

Fix several typos and references to non-existing headers.
Also use __BYTE_ORDER__ instead of __BYTE_ORDER for consistency with
the rest of the bpf code - see commit 45f2bebc80 ("libbpf: Fix
endianness detection in BPF_CORE_READ_BITFIELD_PROBED()") for
rationale).

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220407214411.257260-2-iii@linux.ibm.com
This commit is contained in:
Ilya Leoshkevich 2022-04-07 23:44:09 +02:00 committed by Andrii Nakryiko
parent ded6dffaed
commit e1b6df598a
2 changed files with 8 additions and 8 deletions

View File

@ -166,7 +166,7 @@ int bpf_usdt_arg(struct pt_regs *ctx, __u64 arg_num, long *res)
case BPF_USDT_ARG_REG_DEREF:
/* Arg is in memory addressed by register, plus some offset
* (e.g., "-4@-1204(%rbp)" in USDT arg spec). Register is
* identified lik with BPF_USDT_ARG_REG case, and the offset
* identified like with BPF_USDT_ARG_REG case, and the offset
* is in arg_spec->val_off. We first fetch register contents
* from pt_regs, then do another user-space probe read to
* fetch argument value itself.
@ -198,7 +198,7 @@ int bpf_usdt_arg(struct pt_regs *ctx, __u64 arg_num, long *res)
/* Retrieve user-specified cookie value provided during attach as
* bpf_usdt_opts.usdt_cookie. This serves the same purpose as BPF cookie
* returned by bpf_get_attach_cookie(). Libbpf's support for USDT is itself
* utilizaing BPF cookies internally, so user can't use BPF cookie directly
* utilizing BPF cookies internally, so user can't use BPF cookie directly
* for USDT programs and has to use bpf_usdt_cookie() API instead.
*/
static inline __noinline

View File

@ -108,7 +108,7 @@
* code through spec map. This allows BPF applications to quickly fetch the
* actual value at runtime using a simple BPF-side code.
*
* With basics out of the way, let's go over less immeditately obvious aspects
* With basics out of the way, let's go over less immediately obvious aspects
* of supporting USDTs.
*
* First, there is no special USDT BPF program type. It is actually just
@ -189,14 +189,14 @@
#define USDT_NOTE_TYPE 3
#define USDT_NOTE_NAME "stapsdt"
/* should match exactly enum __bpf_usdt_arg_type from bpf_usdt.bpf.h */
/* should match exactly enum __bpf_usdt_arg_type from usdt.bpf.h */
enum usdt_arg_type {
USDT_ARG_CONST,
USDT_ARG_REG,
USDT_ARG_REG_DEREF,
};
/* should match exactly struct __bpf_usdt_arg_spec from bpf_usdt.bpf.h */
/* should match exactly struct __bpf_usdt_arg_spec from usdt.bpf.h */
struct usdt_arg_spec {
__u64 val_off;
enum usdt_arg_type arg_type;
@ -328,9 +328,9 @@ static int sanity_check_usdt_elf(Elf *elf, const char *path)
return -EBADF;
}
#if __BYTE_ORDER == __LITTLE_ENDIAN
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
endianness = ELFDATA2LSB;
#elif __BYTE_ORDER == __BIG_ENDIAN
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
endianness = ELFDATA2MSB;
#else
# error "Unrecognized __BYTE_ORDER__"
@ -843,7 +843,7 @@ static int bpf_link_usdt_detach(struct bpf_link *link)
sizeof(*new_free_ids));
/* If we couldn't resize free_spec_ids, we'll just leak
* a bunch of free IDs; this is very unlikely to happen and if
* system is so exausted on memory, it's the least of user's
* system is so exhausted on memory, it's the least of user's
* concerns, probably.
* So just do our best here to return those IDs to usdt_manager.
*/