diff mbox series

[kvm-unit-tests,v7,3/4] s390x: lib: add SPX and STPX instruction wrapper

Message ID 20200110184050.191506-4-imbrenda@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390x: SCLP Unit test | expand

Commit Message

Claudio Imbrenda Jan. 10, 2020, 6:40 p.m. UTC
Add a wrapper for the SET PREFIX and STORE PREFIX instructions, and
use it instead of using inline assembly.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
---
 lib/s390x/asm/arch_def.h | 13 +++++++++++++
 s390x/intercept.c        | 23 ++++++++---------------
 2 files changed, 21 insertions(+), 15 deletions(-)

Comments

Janosch Frank Jan. 13, 2020, 9:42 a.m. UTC | #1
On 1/10/20 7:40 PM, Claudio Imbrenda wrote:
> Add a wrapper for the SET PREFIX and STORE PREFIX instructions, and
> use it instead of using inline assembly.
> 
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> Reviewed-by: Thomas Huth <thuth@redhat.com>

Reviewed-by: Janosch Frank <frankja@linux.ibm.com>

> @@ -63,14 +60,10 @@ static void test_spx(void)
>  	 * some facility bits there ... at least some of them should be
>  	 * set in our buffer afterwards.
>  	 */
> -	asm volatile (
> -		" stpx	%0\n"
> -		" spx	%1\n"
> -		" stfl	0\n"
> -		" spx	%0\n"
> -		: "+Q"(old_prefix)
> -		: "Q"(new_prefix)
> -		: "memory");
> +	old_prefix = get_prefix();
> +	set_prefix(new_prefix);
> +	asm volatile("	stfl 0" : : : "memory");

Couldn't we also use stfl from facility.h here?
And do we need to add a memory clobber to it?

> +	set_prefix(old_prefix);
>  	report(pagebuf[GEN_LC_STFL] != 0, "stfl to new prefix");
>  
>  	expect_pgm_int();
>
David Hildenbrand Jan. 13, 2020, 10:42 a.m. UTC | #2
On 10.01.20 19:40, Claudio Imbrenda wrote:
> Add a wrapper for the SET PREFIX and STORE PREFIX instructions, and
> use it instead of using inline assembly.
> 
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> ---
>  lib/s390x/asm/arch_def.h | 13 +++++++++++++
>  s390x/intercept.c        | 23 ++++++++---------------
>  2 files changed, 21 insertions(+), 15 deletions(-)
> 
> diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
> index 1a5e3c6..15a4d49 100644
> --- a/lib/s390x/asm/arch_def.h
> +++ b/lib/s390x/asm/arch_def.h
> @@ -284,4 +284,17 @@ static inline int servc(uint32_t command, unsigned long sccb)
>  	return cc;
>  }
>  
> +static inline void set_prefix(uint32_t new_prefix)
> +{
> +	asm volatile("	spx %0" : : "Q" (new_prefix) : "memory");
> +}
> +
> +static inline uint32_t get_prefix(void)
> +{
> +	uint32_t current_prefix;
> +
> +	asm volatile("	stpx %0" : "=Q" (current_prefix));
> +	return current_prefix;
> +}
> +
>  #endif
> diff --git a/s390x/intercept.c b/s390x/intercept.c
> index 3696e33..cd96121 100644
> --- a/s390x/intercept.c
> +++ b/s390x/intercept.c
> @@ -26,13 +26,10 @@ static void test_stpx(void)
>  	uint32_t new_prefix = (uint32_t)(intptr_t)pagebuf;
>  
>  	/* Can we successfully change the prefix? */
> -	asm volatile (
> -		" stpx	%0\n"
> -		" spx	%2\n"
> -		" stpx	%1\n"
> -		" spx	%0\n"
> -		: "+Q"(old_prefix), "+Q"(tst_prefix)
> -		: "Q"(new_prefix));
> +	old_prefix = get_prefix();
> +	set_prefix(new_prefix);
> +	tst_prefix = get_prefix();
> +	set_prefix(old_prefix);
>  	report(old_prefix == 0 && tst_prefix == new_prefix, "store prefix");
>  
>  	expect_pgm_int();
> @@ -63,14 +60,10 @@ static void test_spx(void)
>  	 * some facility bits there ... at least some of them should be
>  	 * set in our buffer afterwards.
>  	 */
> -	asm volatile (
> -		" stpx	%0\n"
> -		" spx	%1\n"
> -		" stfl	0\n"
> -		" spx	%0\n"
> -		: "+Q"(old_prefix)
> -		: "Q"(new_prefix)
> -		: "memory");
> +	old_prefix = get_prefix();
> +	set_prefix(new_prefix);
> +	asm volatile("	stfl 0" : : : "memory");
> +	set_prefix(old_prefix);
>  	report(pagebuf[GEN_LC_STFL] != 0, "stfl to new prefix");
>  
>  	expect_pgm_int();
> 

Besides the comments from Janosch, looks good to me.
Claudio Imbrenda Jan. 13, 2020, 12:27 p.m. UTC | #3
On Mon, 13 Jan 2020 10:42:01 +0100
Janosch Frank <frankja@linux.ibm.com> wrote:

> On 1/10/20 7:40 PM, Claudio Imbrenda wrote:
> > Add a wrapper for the SET PREFIX and STORE PREFIX instructions, and
> > use it instead of using inline assembly.
> > 
> > Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> > Reviewed-by: Thomas Huth <thuth@redhat.com>  
> 
> Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
> 
> > @@ -63,14 +60,10 @@ static void test_spx(void)
> >  	 * some facility bits there ... at least some of them
> > should be
> >  	 * set in our buffer afterwards.
> >  	 */
> > -	asm volatile (
> > -		" stpx	%0\n"
> > -		" spx	%1\n"
> > -		" stfl	0\n"
> > -		" spx	%0\n"
> > -		: "+Q"(old_prefix)
> > -		: "Q"(new_prefix)
> > -		: "memory");
> > +	old_prefix = get_prefix();
> > +	set_prefix(new_prefix);
> > +	asm volatile("	stfl 0" : : : "memory");  
> 
> Couldn't we also use stfl from facility.h here?
> And do we need to add a memory clobber to it?

will do both

> > +	set_prefix(old_prefix);
> >  	report(pagebuf[GEN_LC_STFL] != 0, "stfl to new prefix");
> >  
> >  	expect_pgm_int();
> >   
> 
>
diff mbox series

Patch

diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
index 1a5e3c6..15a4d49 100644
--- a/lib/s390x/asm/arch_def.h
+++ b/lib/s390x/asm/arch_def.h
@@ -284,4 +284,17 @@  static inline int servc(uint32_t command, unsigned long sccb)
 	return cc;
 }
 
+static inline void set_prefix(uint32_t new_prefix)
+{
+	asm volatile("	spx %0" : : "Q" (new_prefix) : "memory");
+}
+
+static inline uint32_t get_prefix(void)
+{
+	uint32_t current_prefix;
+
+	asm volatile("	stpx %0" : "=Q" (current_prefix));
+	return current_prefix;
+}
+
 #endif
diff --git a/s390x/intercept.c b/s390x/intercept.c
index 3696e33..cd96121 100644
--- a/s390x/intercept.c
+++ b/s390x/intercept.c
@@ -26,13 +26,10 @@  static void test_stpx(void)
 	uint32_t new_prefix = (uint32_t)(intptr_t)pagebuf;
 
 	/* Can we successfully change the prefix? */
-	asm volatile (
-		" stpx	%0\n"
-		" spx	%2\n"
-		" stpx	%1\n"
-		" spx	%0\n"
-		: "+Q"(old_prefix), "+Q"(tst_prefix)
-		: "Q"(new_prefix));
+	old_prefix = get_prefix();
+	set_prefix(new_prefix);
+	tst_prefix = get_prefix();
+	set_prefix(old_prefix);
 	report(old_prefix == 0 && tst_prefix == new_prefix, "store prefix");
 
 	expect_pgm_int();
@@ -63,14 +60,10 @@  static void test_spx(void)
 	 * some facility bits there ... at least some of them should be
 	 * set in our buffer afterwards.
 	 */
-	asm volatile (
-		" stpx	%0\n"
-		" spx	%1\n"
-		" stfl	0\n"
-		" spx	%0\n"
-		: "+Q"(old_prefix)
-		: "Q"(new_prefix)
-		: "memory");
+	old_prefix = get_prefix();
+	set_prefix(new_prefix);
+	asm volatile("	stfl 0" : : : "memory");
+	set_prefix(old_prefix);
 	report(pagebuf[GEN_LC_STFL] != 0, "stfl to new prefix");
 
 	expect_pgm_int();