selftests/bpf: Add a test for objects stuck in free_by_rcu_ttracegrafted

Delete all elements of BPF_F_NO_PREALLOC hash map in one batch. The first
free_bulk() starts RCU tasks trace GP and the rest of the elements are
freed while it's in flight. Wait for call_rcu_ttrace_in_progress to clear
in bpf_mem_cache of every cpu and check that free_by_rcu_ttrace and
waiting_for_gp_ttrace lists are empty.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20260930095920.601738-4-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 47 insertions, 0 deletions

diff --git a/lib/trace_readwrite.c b/lib/trace_readwrite.c
new file mode 100644
index 000000000..a94cd56a1
--- /dev/null
+++ b/lib/trace_readwrite.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Register read and write tracepoints
+ *
+ * Copyright (c) 2021-2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/ftrace.h>
+#include <linux/module.h>
+#include <linux/io.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/rwmmio.h>
+
+#ifdef CONFIG_TRACE_MMIO_ACCESS
+void log_write_mmio(u64 val, u8 width, volatile void __iomem *addr,
+		    unsigned long caller_addr, unsigned long caller_addr0)
+{
+	trace_rwmmio_write(caller_addr, caller_addr0, val, width, addr);
+}
+EXPORT_SYMBOL_GPL(log_write_mmio);
+EXPORT_TRACEPOINT_SYMBOL_GPL(rwmmio_write);
+
+void log_post_write_mmio(u64 val, u8 width, volatile void __iomem *addr,
+			 unsigned long caller_addr, unsigned long caller_addr0)
+{
+	trace_rwmmio_post_write(caller_addr, caller_addr0, val, width, addr);
+}
+EXPORT_SYMBOL_GPL(log_post_write_mmio);
+EXPORT_TRACEPOINT_SYMBOL_GPL(rwmmio_post_write);
+
+void log_read_mmio(u8 width, const volatile void __iomem *addr,
+		   unsigned long caller_addr, unsigned long caller_addr0)
+{
+	trace_rwmmio_read(caller_addr, caller_addr0, width, addr);
+}
+EXPORT_SYMBOL_GPL(log_read_mmio);
+EXPORT_TRACEPOINT_SYMBOL_GPL(rwmmio_read);
+
+void log_post_read_mmio(u64 val, u8 width, const volatile void __iomem *addr,
+			unsigned long caller_addr, unsigned long caller_addr0)
+{
+	trace_rwmmio_post_read(caller_addr, caller_addr0, val, width, addr);
+}
+EXPORT_SYMBOL_GPL(log_post_read_mmio);
+EXPORT_TRACEPOINT_SYMBOL_GPL(rwmmio_post_read);
+#endif /* CONFIG_TRACE_MMIO_ACCESS */