xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

selftests/bpf: Add bpf_read_branch_records() selftest

Browse Source 
Add a selftest to test:

* default bpf_read_branch_records() behavior
* BPF_F_GET_BRANCH_RECORDS_SIZE flag behavior
* error path on non branch record perf events
* using helper to write to stack
* using helper to write to global

On host with hardware counter support:

    # ./test_progs -t perf_branches
    #27/1 perf_branches_hw:OK
    #27/2 perf_branches_no_hw:OK
    #27 perf_branches:OK
    Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED

On host without hardware counter support (VM):

    # ./test_progs -t perf_branches
    #27/1 perf_branches_hw:OK
    #27/2 perf_branches_no_hw:OK
    #27 perf_branches:OK
    Summary: 1/2 PASSED, 1 SKIPPED, 0 FAILED

Also sync tools/include/uapi/linux/bpf.h.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200218030432.4600-3-dxu@dxuuu.xyz
This commit is contained in:
Daniel Xu
2020-02-17 19:04:32 -08:00
committed by Alexei Starovoitov
parent fff7b64355
commit 67306f84ca
3 changed files with 244 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
tools/include/uapi/linux/bpf.h
View File

@@ -2892,6 +2892,25 @@ union bpf_attr {
* Obtain the 64bit jiffies
* Return
* The 64 bit jiffies
*
* int bpf_read_branch_records(struct bpf_perf_event_data *ctx, void *buf, u32 size, u64 flags)
* Description
* For an eBPF program attached to a perf event, retrieve the
* branch records (struct perf_branch_entry) associated to *ctx*
* and store it in the buffer pointed by *buf* up to size
* *size* bytes.
* Return
* On success, number of bytes written to *buf*. On error, a
* negative value.
*
* The *flags* can be set to **BPF_F_GET_BRANCH_RECORDS_SIZE** to
* instead return the number of bytes required to store all the
* branch entries. If this flag is set, *buf* may be NULL.
*
* **-EINVAL** if arguments invalid or **size** not a multiple
* of sizeof(struct perf_branch_entry).
*
* **-ENOENT** if architecture does not support branch records.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -3012,7 +3031,8 @@ union bpf_attr {
FN(probe_read_kernel_str), \
FN(tcp_send_ack), \
FN(send_signal_thread), \
FN(jiffies64),
FN(jiffies64), \
FN(read_branch_records),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
@@ -3091,6 +3111,9 @@ enum bpf_func_id {
/* BPF_FUNC_sk_storage_get flags */
#define BPF_SK_STORAGE_GET_F_CREATE (1ULL << 0)
/* BPF_FUNC_read_branch_records flags. */
#define BPF_F_GET_BRANCH_RECORDS_SIZE (1ULL << 0)
/* Mode for BPF_FUNC_skb_adjust_room helper. */
enum bpf_adj_room_mode {
BPF_ADJ_ROOM_NET,