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, 306 insertions, 0 deletions

diff --git a/drivers/s390/cio/ioasm.c b/drivers/s390/cio/ioasm.c
new file mode 100644
index 000000000..8b06b234e
--- /dev/null
+++ b/drivers/s390/cio/ioasm.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Channel subsystem I/O instructions.
+ */
+
+#include <linux/export.h>
+
+#include <asm/asm-extable.h>
+#include <asm/chpid.h>
+#include <asm/schid.h>
+#include <asm/asm.h>
+#include <asm/crw.h>
+
+#include "ioasm.h"
+#include "orb.h"
+#include "cio.h"
+#include "cio_inject.h"
+
+static inline int __stsch(struct subchannel_id schid, struct schib *addr)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode, exception;
+
+	exception = 1;
+	asm_inline volatile(
+		"	lgr	1,%[r1]\n"
+		"	stsch	%[addr]\n"
+		"0:	lhi	%[exc],0\n"
+		"1:\n"
+		CC_IPM(cc)
+		EX_TABLE(0b, 1b)
+		: CC_OUT(cc, ccode), [addr] "=Q" (*addr), [exc] "+d" (exception)
+		: [r1] "d" (r1)
+		: CC_CLOBBER_LIST("1"));
+	return exception ? -EIO : CC_TRANSFORM(ccode);
+}
+
+int stsch(struct subchannel_id schid, struct schib *addr)
+{
+	int ccode;
+
+	ccode = __stsch(schid, addr);
+	trace_s390_cio_stsch(schid, addr, ccode);
+
+	return ccode;
+}
+EXPORT_SYMBOL(stsch);
+
+static inline int __msch(struct subchannel_id schid, struct schib *addr)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode, exception;
+
+	exception = 1;
+	asm_inline volatile(
+		"	lgr	1,%[r1]\n"
+		"	msch	%[addr]\n"
+		"0:	lhi	%[exc],0\n"
+		"1:\n"
+		CC_IPM(cc)
+		EX_TABLE(0b, 1b)
+		: CC_OUT(cc, ccode), [exc] "+d" (exception)
+		: [r1] "d" (r1), [addr] "Q" (*addr)
+		: CC_CLOBBER_LIST("1"));
+	return exception ? -EIO : CC_TRANSFORM(ccode);
+}
+
+int msch(struct subchannel_id schid, struct schib *addr)
+{
+	int ccode;
+
+	ccode = __msch(schid, addr);
+	trace_s390_cio_msch(schid, addr, ccode);
+
+	return ccode;
+}
+
+static inline int __tsch(struct subchannel_id schid, struct irb *addr)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode;
+
+	asm volatile(
+		"	lgr	1,%[r1]\n"
+		"	tsch	%[addr]\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, ccode), [addr] "=Q" (*addr)
+		: [r1] "d" (r1)
+		: CC_CLOBBER_LIST("1"));
+	return CC_TRANSFORM(ccode);
+}
+
+int tsch(struct subchannel_id schid, struct irb *addr)
+{
+	int ccode;
+
+	ccode = __tsch(schid, addr);
+	trace_s390_cio_tsch(schid, addr, ccode);
+
+	return ccode;
+}
+
+static inline int __ssch(struct subchannel_id schid, union orb *addr)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode, exception;
+
+	exception = 1;
+	asm_inline volatile(
+		"	lgr	1,%[r1]\n"
+		"	ssch	%[addr]\n"
+		"0:	lhi	%[exc],0\n"
+		"1:\n"
+		CC_IPM(cc)
+		EX_TABLE(0b, 1b)
+		: CC_OUT(cc, ccode), [exc] "+d" (exception)
+		: [r1] "d" (r1), [addr] "Q" (*addr)
+		: CC_CLOBBER_LIST("memory", "1"));
+	return CC_TRANSFORM(ccode);
+}
+
+int ssch(struct subchannel_id schid, union orb *addr)
+{
+	int ccode;
+
+	ccode = __ssch(schid, addr);
+	trace_s390_cio_ssch(schid, addr, ccode);
+
+	return ccode;
+}
+EXPORT_SYMBOL(ssch);
+
+static inline int __csch(struct subchannel_id schid)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode;
+
+	asm volatile(
+		"	lgr	1,%[r1]\n"
+		"	csch\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, ccode)
+		: [r1] "d" (r1)
+		: CC_CLOBBER_LIST("1"));
+	return CC_TRANSFORM(ccode);
+}
+
+int csch(struct subchannel_id schid)
+{
+	int ccode;
+
+	ccode = __csch(schid);
+	trace_s390_cio_csch(schid, ccode);
+
+	return ccode;
+}
+EXPORT_SYMBOL(csch);
+
+int tpi(struct tpi_info *addr)
+{
+	int ccode;
+
+	asm volatile(
+		"	tpi	%[addr]\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, ccode), [addr] "=Q" (*addr)
+		:
+		: CC_CLOBBER);
+	ccode = CC_TRANSFORM(ccode);
+	trace_s390_cio_tpi(addr, ccode);
+
+	return ccode;
+}
+
+int chsc(void *chsc_area)
+{
+	typedef struct { char _[4096]; } addr_type;
+	int cc, exception;
+
+	exception = 1;
+	asm_inline volatile(
+		"	.insn	rre,0xb25f0000,%[chsc_area],0\n"
+		"0:	lhi	%[exc],0\n"
+		"1:\n"
+		CC_IPM(cc)
+		EX_TABLE(0b, 1b)
+		: CC_OUT(cc, cc), "+m" (*(addr_type *)chsc_area), [exc] "+d" (exception)
+		: [chsc_area] "d" (chsc_area)
+		: CC_CLOBBER);
+	cc = exception ? -EIO : CC_TRANSFORM(cc);
+	trace_s390_cio_chsc(chsc_area, cc);
+
+	return cc;
+}
+EXPORT_SYMBOL(chsc);
+
+static inline int __rsch(struct subchannel_id schid)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode;
+
+	asm volatile(
+		"	lgr	1,%[r1]\n"
+		"	rsch\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, ccode)
+		: [r1] "d" (r1)
+		: CC_CLOBBER_LIST("memory", "1"));
+	return CC_TRANSFORM(ccode);
+}
+
+int rsch(struct subchannel_id schid)
+{
+	int ccode;
+
+	ccode = __rsch(schid);
+	trace_s390_cio_rsch(schid, ccode);
+
+	return ccode;
+}
+
+static inline int __hsch(struct subchannel_id schid)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode;
+
+	asm volatile(
+		"	lgr	1,%[r1]\n"
+		"	hsch\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, ccode)
+		: [r1] "d" (r1)
+		: CC_CLOBBER_LIST("1"));
+	return CC_TRANSFORM(ccode);
+}
+
+int hsch(struct subchannel_id schid)
+{
+	int ccode;
+
+	ccode = __hsch(schid);
+	trace_s390_cio_hsch(schid, ccode);
+
+	return ccode;
+}
+EXPORT_SYMBOL(hsch);
+
+static inline int __xsch(struct subchannel_id schid)
+{
+	unsigned long r1 = *(unsigned int *)&schid;
+	int ccode;
+
+	asm volatile(
+		"	lgr	1,%[r1]\n"
+		"	xsch\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, ccode)
+		: [r1] "d" (r1)
+		: CC_CLOBBER_LIST("1"));
+	return CC_TRANSFORM(ccode);
+}
+
+int xsch(struct subchannel_id schid)
+{
+	int ccode;
+
+	ccode = __xsch(schid);
+	trace_s390_cio_xsch(schid, ccode);
+
+	return ccode;
+}
+
+static inline int __stcrw(struct crw *crw)
+{
+	int ccode;
+
+	asm volatile(
+		"	stcrw	%[crw]\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, ccode), [crw] "=Q" (*crw)
+		:
+		: CC_CLOBBER);
+	return CC_TRANSFORM(ccode);
+}
+
+static inline int _stcrw(struct crw *crw)
+{
+#ifdef CONFIG_CIO_INJECT
+	if (static_branch_unlikely(&cio_inject_enabled)) {
+		if (stcrw_get_injected(crw) == 0)
+			return 0;
+	}
+#endif
+
+	return __stcrw(crw);
+}
+
+int stcrw(struct crw *crw)
+{
+	int ccode;
+
+	ccode = _stcrw(crw);
+	trace_s390_cio_stcrw(crw, ccode);
+
+	return ccode;
+}