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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /samples/user_events | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'samples/user_events')
-rw-r--r-- | samples/user_events/Makefile | 5 | ||||
-rw-r--r-- | samples/user_events/example.c | 73 |
2 files changed, 78 insertions, 0 deletions
diff --git a/samples/user_events/Makefile b/samples/user_events/Makefile new file mode 100644 index 0000000000..7252b589db --- /dev/null +++ b/samples/user_events/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 +CFLAGS += -Wl,-no-as-needed -Wall -I../../usr/include + +example: example.o +example.o: example.c diff --git a/samples/user_events/example.c b/samples/user_events/example.c new file mode 100644 index 0000000000..28165a0966 --- /dev/null +++ b/samples/user_events/example.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2021, Microsoft Corporation. + * + * Authors: + * Beau Belgrave <beaub@linux.microsoft.com> + */ + +#include <errno.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/uio.h> +#include <fcntl.h> +#include <stdio.h> +#include <unistd.h> +#include <linux/user_events.h> + +const char *data_file = "/sys/kernel/tracing/user_events_data"; +int enabled = 0; + +static int event_reg(int fd, const char *command, int *write, int *enabled) +{ + struct user_reg reg = {0}; + + reg.size = sizeof(reg); + reg.enable_bit = 31; + reg.enable_size = sizeof(*enabled); + reg.enable_addr = (__u64)enabled; + reg.name_args = (__u64)command; + + if (ioctl(fd, DIAG_IOCSREG, ®) == -1) + return -1; + + *write = reg.write_index; + + return 0; +} + +int main(int argc, char **argv) +{ + int data_fd, write; + struct iovec io[2]; + __u32 count = 0; + + data_fd = open(data_file, O_RDWR); + + if (event_reg(data_fd, "test u32 count", &write, &enabled) == -1) + return errno; + + /* Setup iovec */ + io[0].iov_base = &write; + io[0].iov_len = sizeof(write); + io[1].iov_base = &count; + io[1].iov_len = sizeof(count); +ask: + printf("Press enter to check status...\n"); + getchar(); + + /* Check if anyone is listening */ + if (enabled) { + /* Yep, trace out our data */ + writev(data_fd, (const struct iovec *)io, 2); + + /* Increase the count */ + count++; + + printf("Something was attached, wrote data\n"); + } + + goto ask; + + return 0; +} |