[PATCH bpf-next] bpf: add 'BPF_RB_MAY_WAKEUP' flag
From: Pedro Tammela
Date: Sun Mar 28 2021 - 12:17:42 EST
The current way to provide a no-op flag to 'bpf_ringbuf_submit()',
'bpf_ringbuf_discard()' and 'bpf_ringbuf_output()' is to provide a '0'
value.
A '0' value might notify the consumer if it already caught up in processing,
so let's provide a more descriptive notation for this value.
Signed-off-by: Pedro Tammela <pctammela@xxxxxxxxxxxx>
---
include/uapi/linux/bpf.h | 8 ++++++++
tools/include/uapi/linux/bpf.h | 8 ++++++++
tools/testing/selftests/bpf/progs/ima.c | 2 +-
tools/testing/selftests/bpf/progs/ringbuf_bench.c | 2 +-
tools/testing/selftests/bpf/progs/test_ringbuf.c | 2 +-
tools/testing/selftests/bpf/progs/test_ringbuf_multi.c | 2 +-
6 files changed, 20 insertions(+), 4 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 598716742593..100cb2e4c104 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -4058,6 +4058,8 @@ union bpf_attr {
* Copy *size* bytes from *data* into a ring buffer *ringbuf*.
* If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
* of new data availability is sent.
+ * If **BPF_RB_MAY_WAKEUP** is specified in *flags*, notification
+ * of new data availability is sent if needed.
* If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
* of new data availability is sent unconditionally.
* Return
@@ -4066,6 +4068,7 @@ union bpf_attr {
* void *bpf_ringbuf_reserve(void *ringbuf, u64 size, u64 flags)
* Description
* Reserve *size* bytes of payload in a ring buffer *ringbuf*.
+ * *flags* must be 0.
* Return
* Valid pointer with *size* bytes of memory available; NULL,
* otherwise.
@@ -4075,6 +4078,8 @@ union bpf_attr {
* Submit reserved ring buffer sample, pointed to by *data*.
* If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
* of new data availability is sent.
+ * If **BPF_RB_MAY_WAKEUP** is specified in *flags*, notification
+ * of new data availability is sent if needed.
* If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
* of new data availability is sent unconditionally.
* Return
@@ -4085,6 +4090,8 @@ union bpf_attr {
* Discard reserved ring buffer sample, pointed to by *data*.
* If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
* of new data availability is sent.
+ * If **BPF_RB_MAY_WAKEUP** is specified in *flags*, notification
+ * of new data availability is sent if needed.
* If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
* of new data availability is sent unconditionally.
* Return
@@ -4965,6 +4972,7 @@ enum {
* BPF_FUNC_bpf_ringbuf_output flags.
*/
enum {
+ BPF_RB_MAY_WAKEUP = 0,
BPF_RB_NO_WAKEUP = (1ULL << 0),
BPF_RB_FORCE_WAKEUP = (1ULL << 1),
};
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index ab9f2233607c..3d6d324184c0 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -4058,6 +4058,8 @@ union bpf_attr {
* Copy *size* bytes from *data* into a ring buffer *ringbuf*.
* If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
* of new data availability is sent.
+ * If **BPF_RB_MAY_WAKEUP** is specified in *flags*, notification
+ * of new data availability is sent if needed.
* If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
* of new data availability is sent unconditionally.
* Return
@@ -4066,6 +4068,7 @@ union bpf_attr {
* void *bpf_ringbuf_reserve(void *ringbuf, u64 size, u64 flags)
* Description
* Reserve *size* bytes of payload in a ring buffer *ringbuf*.
+ * *flags* must be 0.
* Return
* Valid pointer with *size* bytes of memory available; NULL,
* otherwise.
@@ -4075,6 +4078,8 @@ union bpf_attr {
* Submit reserved ring buffer sample, pointed to by *data*.
* If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
* of new data availability is sent.
+ * If **BPF_RB_MAY_WAKEUP** is specified in *flags*, notification
+ * of new data availability is sent if needed.
* If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
* of new data availability is sent unconditionally.
* Return
@@ -4085,6 +4090,8 @@ union bpf_attr {
* Discard reserved ring buffer sample, pointed to by *data*.
* If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
* of new data availability is sent.
+ * If **BPF_RB_MAY_WAKEUP** is specified in *flags*, notification
+ * of new data availability is sent if needed.
* If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
* of new data availability is sent unconditionally.
* Return
@@ -4959,6 +4966,7 @@ enum {
* BPF_FUNC_bpf_ringbuf_output flags.
*/
enum {
+ BPF_RB_MAY_WAKEUP = 0,
BPF_RB_NO_WAKEUP = (1ULL << 0),
BPF_RB_FORCE_WAKEUP = (1ULL << 1),
};
diff --git a/tools/testing/selftests/bpf/progs/ima.c b/tools/testing/selftests/bpf/progs/ima.c
index 96060ff4ffc6..0f4daced6aad 100644
--- a/tools/testing/selftests/bpf/progs/ima.c
+++ b/tools/testing/selftests/bpf/progs/ima.c
@@ -38,7 +38,7 @@ void BPF_PROG(ima, struct linux_binprm *bprm)
return;
*sample = ima_hash;
- bpf_ringbuf_submit(sample, 0);
+ bpf_ringbuf_submit(sample, BPF_RB_MAY_WAKEUP);
}
return;
diff --git a/tools/testing/selftests/bpf/progs/ringbuf_bench.c b/tools/testing/selftests/bpf/progs/ringbuf_bench.c
index 123607d314d6..808e2e0e3d64 100644
--- a/tools/testing/selftests/bpf/progs/ringbuf_bench.c
+++ b/tools/testing/selftests/bpf/progs/ringbuf_bench.c
@@ -24,7 +24,7 @@ static __always_inline long get_flags()
long sz;
if (!wakeup_data_size)
- return 0;
+ return BPF_RB_MAY_WAKEUP;
sz = bpf_ringbuf_query(&ringbuf, BPF_RB_AVAIL_DATA);
return sz >= wakeup_data_size ? BPF_RB_FORCE_WAKEUP : BPF_RB_NO_WAKEUP;
diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf.c b/tools/testing/selftests/bpf/progs/test_ringbuf.c
index 8ba9959b036b..03a5cbd21356 100644
--- a/tools/testing/selftests/bpf/progs/test_ringbuf.c
+++ b/tools/testing/selftests/bpf/progs/test_ringbuf.c
@@ -21,7 +21,7 @@ struct {
/* inputs */
int pid = 0;
long value = 0;
-long flags = 0;
+long flags = BPF_RB_MAY_WAKEUP;
/* outputs */
long total = 0;
diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
index edf3b6953533..f33c3fdfb1d6 100644
--- a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
+++ b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
@@ -71,7 +71,7 @@ int test_ringbuf(void *ctx)
sample->seq = total;
total += 1;
- bpf_ringbuf_submit(sample, 0);
+ bpf_ringbuf_submit(sample, BPF_RB_MAY_WAKEUP);
return 0;
}
--
2.25.1