diff mbox series

[v8,2/3] rseq/selftests: add rseq_offset_deref_addv

Message ID 20200923233618.2572849-2-posk@google.com
State New
Headers show
Series [v8,1/3] rseq/membarrier: add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ | expand

Commit Message

Peter Oskolkov Sept. 23, 2020, 11:36 p.m. UTC
This patch adds rseq_offset_deref_addv function to
tools/testing/selftests/rseq/rseq-x86.h, to be used
in a selftest in the next patch in the patchset.

v7->v8: this patch split out of the v7 selftest patch.

Signed-off-by: Peter Oskolkov <posk@google.com>
---
 tools/testing/selftests/rseq/rseq-x86.h | 57 +++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

Comments

Mathieu Desnoyers Sept. 24, 2020, 1:33 p.m. UTC | #1
----- On Sep 23, 2020, at 7:36 PM, Peter Oskolkov posk@google.com wrote:

The patch title should state that it only adds rseq_offset_deref_addv
to x86-64. Considering that other architecture maintainers will look
at it as inspiration for other architectures, we should also state in
the commit message that architectures implementing it should define
"RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV".

Thanks,

Mathieu

> This patch adds rseq_offset_deref_addv function to
> tools/testing/selftests/rseq/rseq-x86.h, to be used
> in a selftest in the next patch in the patchset.
> 
> v7->v8: this patch split out of the v7 selftest patch.
> 
> Signed-off-by: Peter Oskolkov <posk@google.com>
> ---
> tools/testing/selftests/rseq/rseq-x86.h | 57 +++++++++++++++++++++++++
> 1 file changed, 57 insertions(+)
> 
> diff --git a/tools/testing/selftests/rseq/rseq-x86.h
> b/tools/testing/selftests/rseq/rseq-x86.h
> index b2da6004fe30..640411518e46 100644
> --- a/tools/testing/selftests/rseq/rseq-x86.h
> +++ b/tools/testing/selftests/rseq/rseq-x86.h
> @@ -279,6 +279,63 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu)
> #endif
> }
> 
> +#define RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV
> +
> +/*
> + *   pval = *(ptr+off)
> + *  *pval += inc;
> + */
> +static inline __attribute__((always_inline))
> +int rseq_offset_deref_addv(intptr_t *ptr, off_t off, intptr_t inc, int cpu)
> +{
> +	RSEQ_INJECT_C(9)
> +
> +	__asm__ __volatile__ goto (
> +		RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
> +#ifdef RSEQ_COMPARE_TWICE
> +		RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
> +#endif
> +		/* Start rseq by storing table entry pointer into rseq_cs. */
> +		RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
> +		RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
> +		RSEQ_INJECT_ASM(3)
> +#ifdef RSEQ_COMPARE_TWICE
> +		RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
> +#endif
> +		/* get p+v */
> +		"movq %[ptr], %%rbx\n\t"
> +		"addq %[off], %%rbx\n\t"
> +		/* get pv */
> +		"movq (%%rbx), %%rcx\n\t"
> +		/* *pv += inc */
> +		"addq %[inc], (%%rcx)\n\t"
> +		"2:\n\t"
> +		RSEQ_INJECT_ASM(4)
> +		RSEQ_ASM_DEFINE_ABORT(4, "", abort)
> +		: /* gcc asm goto does not allow outputs */
> +		: [cpu_id]		"r" (cpu),
> +		  [rseq_abi]		"r" (&__rseq_abi),
> +		  /* final store input */
> +		  [ptr]			"m" (*ptr),
> +		  [off]			"er" (off),
> +		  [inc]			"er" (inc)
> +		: "memory", "cc", "rax", "rbx", "rcx"
> +		  RSEQ_INJECT_CLOBBER
> +		: abort
> +#ifdef RSEQ_COMPARE_TWICE
> +		  , error1
> +#endif
> +	);
> +	return 0;
> +abort:
> +	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,
> --
> 2.28.0.709.gb0816b6eb0-goog
Mathieu Desnoyers Sept. 24, 2020, 1:54 p.m. UTC | #2
----- On Sep 24, 2020, at 9:33 AM, Mathieu Desnoyers mathieu.desnoyers@efficios.com wrote:

> ----- On Sep 23, 2020, at 7:36 PM, Peter Oskolkov posk@google.com wrote:
> 
> The patch title should state that it only adds rseq_offset_deref_addv
> to x86-64. Considering that other architecture maintainers will look
> at it as inspiration for other architectures, we should also state in
> the commit message that architectures implementing it should define
> "RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV".

With those changes applied, you can also add my:

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>


Thanks,

Mathieu

> 
> Thanks,
> 
> Mathieu
> 
>> This patch adds rseq_offset_deref_addv function to
>> tools/testing/selftests/rseq/rseq-x86.h, to be used
>> in a selftest in the next patch in the patchset.
>> 
>> v7->v8: this patch split out of the v7 selftest patch.
>> 
>> Signed-off-by: Peter Oskolkov <posk@google.com>
>> ---
>> tools/testing/selftests/rseq/rseq-x86.h | 57 +++++++++++++++++++++++++
>> 1 file changed, 57 insertions(+)
>> 
>> diff --git a/tools/testing/selftests/rseq/rseq-x86.h
>> b/tools/testing/selftests/rseq/rseq-x86.h
>> index b2da6004fe30..640411518e46 100644
>> --- a/tools/testing/selftests/rseq/rseq-x86.h
>> +++ b/tools/testing/selftests/rseq/rseq-x86.h
>> @@ -279,6 +279,63 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu)
>> #endif
>> }
>> 
>> +#define RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV
>> +
>> +/*
>> + *   pval = *(ptr+off)
>> + *  *pval += inc;
>> + */
>> +static inline __attribute__((always_inline))
>> +int rseq_offset_deref_addv(intptr_t *ptr, off_t off, intptr_t inc, int cpu)
>> +{
>> +	RSEQ_INJECT_C(9)
>> +
>> +	__asm__ __volatile__ goto (
>> +		RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
>> +#ifdef RSEQ_COMPARE_TWICE
>> +		RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
>> +#endif
>> +		/* Start rseq by storing table entry pointer into rseq_cs. */
>> +		RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
>> +		RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
>> +		RSEQ_INJECT_ASM(3)
>> +#ifdef RSEQ_COMPARE_TWICE
>> +		RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
>> +#endif
>> +		/* get p+v */
>> +		"movq %[ptr], %%rbx\n\t"
>> +		"addq %[off], %%rbx\n\t"
>> +		/* get pv */
>> +		"movq (%%rbx), %%rcx\n\t"
>> +		/* *pv += inc */
>> +		"addq %[inc], (%%rcx)\n\t"
>> +		"2:\n\t"
>> +		RSEQ_INJECT_ASM(4)
>> +		RSEQ_ASM_DEFINE_ABORT(4, "", abort)
>> +		: /* gcc asm goto does not allow outputs */
>> +		: [cpu_id]		"r" (cpu),
>> +		  [rseq_abi]		"r" (&__rseq_abi),
>> +		  /* final store input */
>> +		  [ptr]			"m" (*ptr),
>> +		  [off]			"er" (off),
>> +		  [inc]			"er" (inc)
>> +		: "memory", "cc", "rax", "rbx", "rcx"
>> +		  RSEQ_INJECT_CLOBBER
>> +		: abort
>> +#ifdef RSEQ_COMPARE_TWICE
>> +		  , error1
>> +#endif
>> +	);
>> +	return 0;
>> +abort:
>> +	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,
>> --
>> 2.28.0.709.gb0816b6eb0-goog
> 
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
diff mbox series

Patch

diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h
index b2da6004fe30..640411518e46 100644
--- a/tools/testing/selftests/rseq/rseq-x86.h
+++ b/tools/testing/selftests/rseq/rseq-x86.h
@@ -279,6 +279,63 @@  int rseq_addv(intptr_t *v, intptr_t count, int cpu)
 #endif
 }
 
+#define RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV
+
+/*
+ *   pval = *(ptr+off)
+ *  *pval += inc;
+ */
+static inline __attribute__((always_inline))
+int rseq_offset_deref_addv(intptr_t *ptr, off_t off, intptr_t inc, int cpu)
+{
+	RSEQ_INJECT_C(9)
+
+	__asm__ __volatile__ goto (
+		RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+#ifdef RSEQ_COMPARE_TWICE
+		RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
+#endif
+		/* Start rseq by storing table entry pointer into rseq_cs. */
+		RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+		RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
+		RSEQ_INJECT_ASM(3)
+#ifdef RSEQ_COMPARE_TWICE
+		RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
+#endif
+		/* get p+v */
+		"movq %[ptr], %%rbx\n\t"
+		"addq %[off], %%rbx\n\t"
+		/* get pv */
+		"movq (%%rbx), %%rcx\n\t"
+		/* *pv += inc */
+		"addq %[inc], (%%rcx)\n\t"
+		"2:\n\t"
+		RSEQ_INJECT_ASM(4)
+		RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+		: /* gcc asm goto does not allow outputs */
+		: [cpu_id]		"r" (cpu),
+		  [rseq_abi]		"r" (&__rseq_abi),
+		  /* final store input */
+		  [ptr]			"m" (*ptr),
+		  [off]			"er" (off),
+		  [inc]			"er" (inc)
+		: "memory", "cc", "rax", "rbx", "rcx"
+		  RSEQ_INJECT_CLOBBER
+		: abort
+#ifdef RSEQ_COMPARE_TWICE
+		  , error1
+#endif
+	);
+	return 0;
+abort:
+	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,