Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2e155fb7 authored by Mathieu Desnoyers's avatar Mathieu Desnoyers Committed by Thomas Gleixner
Browse files

rseq/selftests: Provide rseq library 



This rseq helper library provides a user-space API to the rseq()
system call.

The rseq fast-path exposes the instruction pointer addresses where the
rseq assembly blocks begin and end, as well as the associated abort
instruction pointer, in the __rseq_table section. This section allows
debuggers may know where to place breakpoints when single-stepping
through assembly blocks which may be aborted at any point by the kernel.

Signed-off-by: default avatarMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: linux-kselftest@vger.kernel.org
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Chris Lameter <cl@linux.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Andrew Hunter <ahh@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Maurer <bmaurer@fb.com>
Cc: linux-api@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20180602124408.8430-13-mathieu.desnoyers@efficios.com
parent 4e49ed2f

tools/testing/selftests/rseq/rseq-arm.h

0 → 100644
+715 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */

/*

 * rseq-arm.h

 *

 * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

 */



#define RSEQ_SIG	0x53053053



#define rseq_smp_mb()	__asm__ __volatile__ ("dmb" ::: "memory", "cc")

#define rseq_smp_rmb()	__asm__ __volatile__ ("dmb" ::: "memory", "cc")

#define rseq_smp_wmb()	__asm__ __volatile__ ("dmb" ::: "memory", "cc")



#define rseq_smp_load_acquire(p)					\

__extension__ ({							\

	__typeof(*p) ____p1 = RSEQ_READ_ONCE(*p);			\

	rseq_smp_mb();							\

	____p1;								\

})



#define rseq_smp_acquire__after_ctrl_dep()	rseq_smp_rmb()



#define rseq_smp_store_release(p, v)					\

do {									\

	rseq_smp_mb();							\

	RSEQ_WRITE_ONCE(*p, v);						\

} while (0)



#ifdef RSEQ_SKIP_FASTPATH

#include "rseq-skip.h"

#else /* !RSEQ_SKIP_FASTPATH */



#define __RSEQ_ASM_DEFINE_TABLE(version, flags,	start_ip,		\

				post_commit_offset, abort_ip)		\

		".pushsection __rseq_table, \"aw\"\n\t"			\

		".balign 32\n\t"					\

		".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \

		".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \

		".popsection\n\t"



#define RSEQ_ASM_DEFINE_TABLE(start_ip, post_commit_ip, abort_ip)	\

	__RSEQ_ASM_DEFINE_TABLE(0x0, 0x0, start_ip,			\

				(post_commit_ip - start_ip), abort_ip)



#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs)		\

		RSEQ_INJECT_ASM(1)					\

		"adr r0, " __rseq_str(cs_label) "\n\t"			\

		"str r0, %[" __rseq_str(rseq_cs) "]\n\t"		\

		__rseq_str(label) ":\n\t"



#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label)		\

		RSEQ_INJECT_ASM(2)					\

		"ldr r0, %[" __rseq_str(current_cpu_id) "]\n\t"	\

		"cmp %[" __rseq_str(cpu_id) "], r0\n\t"		\

		"bne " __rseq_str(label) "\n\t"



#define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown,		\

				abort_label, version, flags,		\

				start_ip, post_commit_offset, abort_ip)	\

		__rseq_str(table_label) ":\n\t"				\

		".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \

		".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \

		".word " __rseq_str(RSEQ_SIG) "\n\t"			\

		__rseq_str(label) ":\n\t"				\

		teardown						\

		"b %l[" __rseq_str(abort_label) "]\n\t"



#define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \

			      start_ip, post_commit_ip, abort_ip)	\

	__RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown,		\

				abort_label, 0x0, 0x0, start_ip,	\

				(post_commit_ip - start_ip), abort_ip)



#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label)		\

		__rseq_str(label) ":\n\t"				\

		teardown						\

		"b %l[" __rseq_str(cmpfail_label) "]\n\t"



#define rseq_workaround_gcc_asm_size_guess()	__asm__ __volatile__("")



static inline __attribute__((always_inline))

int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)

{

	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[cmpfail]\n\t"

		RSEQ_INJECT_ASM(4)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[error2]\n\t"

#endif

		/* final store */

		"str %[newv], %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(5)

		"b 5f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)

		"5:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  [v]			"m" (*v),

		  [expect]		"r" (expect),

		  [newv]		"r" (newv)

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort, cmpfail

#ifdef RSEQ_COMPARE_TWICE

		  , error1, error2

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

cmpfail:

	rseq_workaround_gcc_asm_size_guess();

	return 1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_bug("cpu_id comparison failed");

error2:

	rseq_bug("expected value comparison failed");

#endif

}



static inline __attribute__((always_inline))

int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,

			       off_t voffp, intptr_t *load, int cpu)

{

	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

		"ldr r0, %[v]\n\t"

		"cmp %[expectnot], r0\n\t"

		"beq %l[cmpfail]\n\t"

		RSEQ_INJECT_ASM(4)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])

		"ldr r0, %[v]\n\t"

		"cmp %[expectnot], r0\n\t"

		"beq %l[error2]\n\t"

#endif

		"str r0, %[load]\n\t"

		"add r0, %[voffp]\n\t"

		"ldr r0, [r0]\n\t"

		/* final store */

		"str r0, %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(5)

		"b 5f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)

		"5:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  /* final store input */

		  [v]			"m" (*v),

		  [expectnot]		"r" (expectnot),

		  [voffp]		"Ir" (voffp),

		  [load]		"m" (*load)

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort, cmpfail

#ifdef RSEQ_COMPARE_TWICE

		  , error1, error2

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

cmpfail:

	rseq_workaround_gcc_asm_size_guess();

	return 1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_bug("cpu_id comparison failed");

error2:

	rseq_bug("expected value comparison failed");

#endif

}



static inline __attribute__((always_inline))

int rseq_addv(intptr_t *v, intptr_t count, int cpu)

{

	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])

#endif

		"ldr r0, %[v]\n\t"

		"add r0, %[count]\n\t"

		/* final store */

		"str r0, %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(4)

		"b 5f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)

		"5:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  [v]			"m" (*v),

		  [count]		"Ir" (count)

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort

#ifdef RSEQ_COMPARE_TWICE

		  , error1

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_bug("cpu_id comparison failed");

#endif

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,

				 intptr_t *v2, intptr_t newv2,

				 intptr_t newv, int cpu)

{

	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[cmpfail]\n\t"

		RSEQ_INJECT_ASM(4)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[error2]\n\t"

#endif

		/* try store */

		"str %[newv2], %[v2]\n\t"

		RSEQ_INJECT_ASM(5)

		/* final store */

		"str %[newv], %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(6)

		"b 5f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)

		"5:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  /* try store input */

		  [v2]			"m" (*v2),

		  [newv2]		"r" (newv2),

		  /* final store input */

		  [v]			"m" (*v),

		  [expect]		"r" (expect),

		  [newv]		"r" (newv)

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort, cmpfail

#ifdef RSEQ_COMPARE_TWICE

		  , error1, error2

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

cmpfail:

	rseq_workaround_gcc_asm_size_guess();

	return 1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_bug("cpu_id comparison failed");

error2:

	rseq_bug("expected value comparison failed");

#endif

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,

					 intptr_t *v2, intptr_t newv2,

					 intptr_t newv, int cpu)

{

	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[cmpfail]\n\t"

		RSEQ_INJECT_ASM(4)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[error2]\n\t"

#endif

		/* try store */

		"str %[newv2], %[v2]\n\t"

		RSEQ_INJECT_ASM(5)

		"dmb\n\t"	/* full mb provides store-release */

		/* final store */

		"str %[newv], %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(6)

		"b 5f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)

		"5:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  /* try store input */

		  [v2]			"m" (*v2),

		  [newv2]		"r" (newv2),

		  /* final store input */

		  [v]			"m" (*v),

		  [expect]		"r" (expect),

		  [newv]		"r" (newv)

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort, cmpfail

#ifdef RSEQ_COMPARE_TWICE

		  , error1, error2

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

cmpfail:

	rseq_workaround_gcc_asm_size_guess();

	return 1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_bug("cpu_id comparison failed");

error2:

	rseq_bug("expected value comparison failed");

#endif

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,

			      intptr_t *v2, intptr_t expect2,

			      intptr_t newv, int cpu)

{

	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[cmpfail]\n\t"

		RSEQ_INJECT_ASM(4)

		"ldr r0, %[v2]\n\t"

		"cmp %[expect2], r0\n\t"

		"bne %l[cmpfail]\n\t"

		RSEQ_INJECT_ASM(5)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne %l[error2]\n\t"

		"ldr r0, %[v2]\n\t"

		"cmp %[expect2], r0\n\t"

		"bne %l[error3]\n\t"

#endif

		/* final store */

		"str %[newv], %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(6)

		"b 5f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)

		"5:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  /* cmp2 input */

		  [v2]			"m" (*v2),

		  [expect2]		"r" (expect2),

		  /* final store input */

		  [v]			"m" (*v),

		  [expect]		"r" (expect),

		  [newv]		"r" (newv)

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort, cmpfail

#ifdef RSEQ_COMPARE_TWICE

		  , error1, error2, error3

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

cmpfail:

	rseq_workaround_gcc_asm_size_guess();

	return 1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_bug("cpu_id comparison failed");

error2:

	rseq_bug("1st expected value comparison failed");

error3:

	rseq_bug("2nd expected value comparison failed");

#endif

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,

				 void *dst, void *src, size_t len,

				 intptr_t newv, int cpu)

{

	uint32_t rseq_scratch[3];



	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		"str %[src], %[rseq_scratch0]\n\t"

		"str %[dst], %[rseq_scratch1]\n\t"

		"str %[len], %[rseq_scratch2]\n\t"

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne 5f\n\t"

		RSEQ_INJECT_ASM(4)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne 7f\n\t"

#endif

		/* try memcpy */

		"cmp %[len], #0\n\t" \

		"beq 333f\n\t" \

		"222:\n\t" \

		"ldrb %%r0, [%[src]]\n\t" \

		"strb %%r0, [%[dst]]\n\t" \

		"adds %[src], #1\n\t" \

		"adds %[dst], #1\n\t" \

		"subs %[len], #1\n\t" \

		"bne 222b\n\t" \

		"333:\n\t" \

		RSEQ_INJECT_ASM(5)

		/* final store */

		"str %[newv], %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(6)

		/* teardown */

		"ldr %[len], %[rseq_scratch2]\n\t"

		"ldr %[dst], %[rseq_scratch1]\n\t"

		"ldr %[src], %[rseq_scratch0]\n\t"

		"b 8f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4,

				      /* teardown */

				      "ldr %[len], %[rseq_scratch2]\n\t"

				      "ldr %[dst], %[rseq_scratch1]\n\t"

				      "ldr %[src], %[rseq_scratch0]\n\t",

				      abort, 1b, 2b, 4f)

		RSEQ_ASM_DEFINE_CMPFAIL(5,

					/* teardown */

					"ldr %[len], %[rseq_scratch2]\n\t"

					"ldr %[dst], %[rseq_scratch1]\n\t"

					"ldr %[src], %[rseq_scratch0]\n\t",

					cmpfail)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_DEFINE_CMPFAIL(6,

					/* teardown */

					"ldr %[len], %[rseq_scratch2]\n\t"

					"ldr %[dst], %[rseq_scratch1]\n\t"

					"ldr %[src], %[rseq_scratch0]\n\t",

					error1)

		RSEQ_ASM_DEFINE_CMPFAIL(7,

					/* teardown */

					"ldr %[len], %[rseq_scratch2]\n\t"

					"ldr %[dst], %[rseq_scratch1]\n\t"

					"ldr %[src], %[rseq_scratch0]\n\t",

					error2)

#endif

		"8:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  /* final store input */

		  [v]			"m" (*v),

		  [expect]		"r" (expect),

		  [newv]		"r" (newv),

		  /* try memcpy input */

		  [dst]			"r" (dst),

		  [src]			"r" (src),

		  [len]			"r" (len),

		  [rseq_scratch0]	"m" (rseq_scratch[0]),

		  [rseq_scratch1]	"m" (rseq_scratch[1]),

		  [rseq_scratch2]	"m" (rseq_scratch[2])

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort, cmpfail

#ifdef RSEQ_COMPARE_TWICE

		  , error1, error2

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

cmpfail:

	rseq_workaround_gcc_asm_size_guess();

	return 1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_workaround_gcc_asm_size_guess();

	rseq_bug("cpu_id comparison failed");

error2:

	rseq_workaround_gcc_asm_size_guess();

	rseq_bug("expected value comparison failed");

#endif

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,

					 void *dst, void *src, size_t len,

					 intptr_t newv, int cpu)

{

	uint32_t rseq_scratch[3];



	RSEQ_INJECT_C(9)



	rseq_workaround_gcc_asm_size_guess();

	__asm__ __volatile__ goto (

		RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */

		"str %[src], %[rseq_scratch0]\n\t"

		"str %[dst], %[rseq_scratch1]\n\t"

		"str %[len], %[rseq_scratch2]\n\t"

		/* Start rseq by storing table entry pointer into rseq_cs. */

		RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)

		RSEQ_INJECT_ASM(3)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne 5f\n\t"

		RSEQ_INJECT_ASM(4)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)

		"ldr r0, %[v]\n\t"

		"cmp %[expect], r0\n\t"

		"bne 7f\n\t"

#endif

		/* try memcpy */

		"cmp %[len], #0\n\t" \

		"beq 333f\n\t" \

		"222:\n\t" \

		"ldrb %%r0, [%[src]]\n\t" \

		"strb %%r0, [%[dst]]\n\t" \

		"adds %[src], #1\n\t" \

		"adds %[dst], #1\n\t" \

		"subs %[len], #1\n\t" \

		"bne 222b\n\t" \

		"333:\n\t" \

		RSEQ_INJECT_ASM(5)

		"dmb\n\t"	/* full mb provides store-release */

		/* final store */

		"str %[newv], %[v]\n\t"

		"2:\n\t"

		RSEQ_INJECT_ASM(6)

		/* teardown */

		"ldr %[len], %[rseq_scratch2]\n\t"

		"ldr %[dst], %[rseq_scratch1]\n\t"

		"ldr %[src], %[rseq_scratch0]\n\t"

		"b 8f\n\t"

		RSEQ_ASM_DEFINE_ABORT(3, 4,

				      /* teardown */

				      "ldr %[len], %[rseq_scratch2]\n\t"

				      "ldr %[dst], %[rseq_scratch1]\n\t"

				      "ldr %[src], %[rseq_scratch0]\n\t",

				      abort, 1b, 2b, 4f)

		RSEQ_ASM_DEFINE_CMPFAIL(5,

					/* teardown */

					"ldr %[len], %[rseq_scratch2]\n\t"

					"ldr %[dst], %[rseq_scratch1]\n\t"

					"ldr %[src], %[rseq_scratch0]\n\t",

					cmpfail)

#ifdef RSEQ_COMPARE_TWICE

		RSEQ_ASM_DEFINE_CMPFAIL(6,

					/* teardown */

					"ldr %[len], %[rseq_scratch2]\n\t"

					"ldr %[dst], %[rseq_scratch1]\n\t"

					"ldr %[src], %[rseq_scratch0]\n\t",

					error1)

		RSEQ_ASM_DEFINE_CMPFAIL(7,

					/* teardown */

					"ldr %[len], %[rseq_scratch2]\n\t"

					"ldr %[dst], %[rseq_scratch1]\n\t"

					"ldr %[src], %[rseq_scratch0]\n\t",

					error2)

#endif

		"8:\n\t"

		: /* gcc asm goto does not allow outputs */

		: [cpu_id]		"r" (cpu),

		  [current_cpu_id]	"m" (__rseq_abi.cpu_id),

		  [rseq_cs]		"m" (__rseq_abi.rseq_cs),

		  /* final store input */

		  [v]			"m" (*v),

		  [expect]		"r" (expect),

		  [newv]		"r" (newv),

		  /* try memcpy input */

		  [dst]			"r" (dst),

		  [src]			"r" (src),

		  [len]			"r" (len),

		  [rseq_scratch0]	"m" (rseq_scratch[0]),

		  [rseq_scratch1]	"m" (rseq_scratch[1]),

		  [rseq_scratch2]	"m" (rseq_scratch[2])

		  RSEQ_INJECT_INPUT

		: "r0", "memory", "cc"

		  RSEQ_INJECT_CLOBBER

		: abort, cmpfail

#ifdef RSEQ_COMPARE_TWICE

		  , error1, error2

#endif

	);

	rseq_workaround_gcc_asm_size_guess();

	return 0;

abort:

	rseq_workaround_gcc_asm_size_guess();

	RSEQ_INJECT_FAILED

	return -1;

cmpfail:

	rseq_workaround_gcc_asm_size_guess();

	return 1;

#ifdef RSEQ_COMPARE_TWICE

error1:

	rseq_workaround_gcc_asm_size_guess();

	rseq_bug("cpu_id comparison failed");

error2:

	rseq_workaround_gcc_asm_size_guess();

	rseq_bug("expected value comparison failed");

#endif

}



#endif /* !RSEQ_SKIP_FASTPATH */

tools/testing/selftests/rseq/rseq-ppc.h

0 → 100644
+671 −0

File added.

Preview size limit exceeded, changes collapsed.

tools/testing/selftests/rseq/rseq-skip.h

0 → 100644
+65 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */

/*

 * rseq-skip.h

 *

 * (C) Copyright 2017-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

 */



static inline __attribute__((always_inline))

int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)

{

	return -1;

}



static inline __attribute__((always_inline))

int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,

			       off_t voffp, intptr_t *load, int cpu)

{

	return -1;

}



static inline __attribute__((always_inline))

int rseq_addv(intptr_t *v, intptr_t count, int cpu)

{

	return -1;

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,

				 intptr_t *v2, intptr_t newv2,

				 intptr_t newv, int cpu)

{

	return -1;

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,

					 intptr_t *v2, intptr_t newv2,

					 intptr_t newv, int cpu)

{

	return -1;

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,

			      intptr_t *v2, intptr_t expect2,

			      intptr_t newv, int cpu)

{

	return -1;

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,

				 void *dst, void *src, size_t len,

				 intptr_t newv, int cpu)

{

	return -1;

}



static inline __attribute__((always_inline))

int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,

					 void *dst, void *src, size_t len,

					 intptr_t newv, int cpu)

{

	return -1;

}

tools/testing/selftests/rseq/rseq-x86.h

0 → 100644
+1132 −0

File added.

Preview size limit exceeded, changes collapsed.

tools/testing/selftests/rseq/rseq.c

0 → 100644
+117 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: LGPL-2.1

/*

 * rseq.c

 *

 * Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; only

 * version 2.1 of the License.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

 * Lesser General Public License for more details.

 */



#define _GNU_SOURCE

#include <errno.h>

#include <sched.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <syscall.h>

#include <assert.h>

#include <signal.h>



#include "rseq.h"



#define ARRAY_SIZE(arr)	(sizeof(arr) / sizeof((arr)[0]))



__attribute__((tls_model("initial-exec"))) __thread

volatile struct rseq __rseq_abi = {

	.cpu_id = RSEQ_CPU_ID_UNINITIALIZED,

};



static __attribute__((tls_model("initial-exec"))) __thread

volatile int refcount;



static void signal_off_save(sigset_t *oldset)

{

	sigset_t set;

	int ret;



	sigfillset(&set);

	ret = pthread_sigmask(SIG_BLOCK, &set, oldset);

	if (ret)

		abort();

}



static void signal_restore(sigset_t oldset)

{

	int ret;



	ret = pthread_sigmask(SIG_SETMASK, &oldset, NULL);

	if (ret)

		abort();

}



static int sys_rseq(volatile struct rseq *rseq_abi, uint32_t rseq_len,

		    int flags, uint32_t sig)

{

	return syscall(__NR_rseq, rseq_abi, rseq_len, flags, sig);

}



int rseq_register_current_thread(void)

{

	int rc, ret = 0;

	sigset_t oldset;



	signal_off_save(&oldset);

	if (refcount++)

		goto end;

	rc = sys_rseq(&__rseq_abi, sizeof(struct rseq), 0, RSEQ_SIG);

	if (!rc) {

		assert(rseq_current_cpu_raw() >= 0);

		goto end;

	}

	if (errno != EBUSY)

		__rseq_abi.cpu_id = -2;

	ret = -1;

	refcount--;

end:

	signal_restore(oldset);

	return ret;

}



int rseq_unregister_current_thread(void)

{

	int rc, ret = 0;

	sigset_t oldset;



	signal_off_save(&oldset);

	if (--refcount)

		goto end;

	rc = sys_rseq(&__rseq_abi, sizeof(struct rseq),

		      RSEQ_FLAG_UNREGISTER, RSEQ_SIG);

	if (!rc)

		goto end;

	ret = -1;

end:

	signal_restore(oldset);

	return ret;

}



int32_t rseq_fallback_current_cpu(void)

{

	int32_t cpu;



	cpu = sched_getcpu();

	if (cpu < 0) {

		perror("sched_getcpu()");

		abort();

	}

	return cpu;

}