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authorSang-Heon Jeon <ekffu200098@gmail.com>2026-08-24 01:18:14 +0900
committerJulia Lawall <Julia.Lawall@inria.fr>2026-08-23 22:12:11 +0200
commit2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c (patch)
treedcc4da1d99f17541c5590ac63c77da4bf372a4ab /samples/user_events
downloadlinux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.tar.gz
linux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.zip
coccinelle: alloc_cast: drop removed allocatorsgrafted
- pci_alloc_consistent() and pci_zalloc_consistent() were removed by commit 7968778914e5 ("PCI: Remove the deprecated "pci-dma-compat.h" API") - kmem_alloc() was removed by commit f078d4ea8276 ("xfs: convert kmem_alloc() to kmalloc()") - kmem_zalloc() was removed by commit 10634530f7ba ("xfs: convert kmem_zalloc() to kzalloc()") - kmem_zone_alloc() and kmem_zone_zalloc() were removed by commit bae633a4a283 ("xfs: remove xfs_zone_{alloc,zalloc} helpers") So drop them from the rules. No functional change. Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Diffstat (limited to 'samples/user_events')
-rw-r--r--samples/user_events/Makefile5
-rw-r--r--samples/user_events/example.c73
2 files changed, 78 insertions, 0 deletions
diff --git a/samples/user_events/Makefile b/samples/user_events/Makefile
new file mode 100644
index 000000000..7252b589d
--- /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 000000000..28165a096
--- /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, &reg) == -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;
+}