On Thu, 2023-01-19 at 12:40 +0100, Marc Hartmayer wrote:
> Define and use a macro for the stack frame size.
>
> Signed-off-by: Marc Hartmayer <mhartmay@xxxxxxxxxxxxx>
Reviewed-by: Nina Schoetterl-Glausch <nsg@xxxxxxxxxxxxx>
> ---
> lib/s390x/asm-offsets.c | 1 +
> s390x/Makefile | 2 +-
> s390x/cstart64.S | 2 +-
> s390x/flat.lds.S | 4 +++-
> s390x/gs.c | 5 +++--
> s390x/macros.S | 4 ++--
> s390x/snippets/c/flat.lds.S | 6 ++++--
> 7 files changed, 15 insertions(+), 9 deletions(-)
>
[...]
> diff --git a/s390x/gs.c b/s390x/gs.c
> index 4993eb8f43a9..2c2b972d7e65 100644
> --- a/s390x/gs.c
> +++ b/s390x/gs.c
> @@ -9,6 +9,7 @@
> * Janosch Frank <frankja@xxxxxxxxxxxxx>
> */
> #include <libcflat.h>
> +#include <asm/asm-offsets.h>
> #include <asm/page.h>
> #include <asm/facility.h>
> #include <asm/interrupt.h>
> @@ -41,8 +42,8 @@ extern void gs_handler_asm(void);
> " aghi %r15,-320\n" /* Allocate stack frame */
One could argue that the macro should be used here also.
320 = stack_size + register_save_area + control_block
> " stmg %r0,%r13,192(%r15)\n" /* Store regs to save area */
> " stg %r14,312(%r15)\n"
> - " la %r2,160(%r15)\n" /* Store gscb address in this_cb */
> - " .insn rxy,0xe30000000049,0,160(%r15)\n" /* stgsc */
> + " la %r2," xstr(STACK_FRAME_SIZE) "(%r15) \n" /* Store gscb address in this_cb */
> + " .insn rxy,0xe30000000049,0," xstr(STACK_FRAME_SIZE) "(%r15)\n" /* stgsc */
The comment indentation is a bit messed up now.
> " lg %r14,24(%r2)\n" /* Get GSEPLA from GSCB*/
> " lg %r14,40(%r14)\n" /* Get GSERA from GSEPL*/
> " stg %r14,304(%r15)\n" /* Store GSERA in r14 of reg save area */
Nothing to do with your changes, but the whitespace in this asm block is pretty messy.
Have a look at the attached patch for some suggestion, but feel free to ignore them.
[...]
diff --git a/s390x/gs.c b/s390x/gs.c
index 2c2b972d..9ae893ea 100644
--- a/s390x/gs.c
+++ b/s390x/gs.c
@@ -36,22 +36,27 @@ static inline unsigned long load_guarded(unsigned long *p)
/* guarded-storage event handler and finally it calls gs_handler */
extern void gs_handler_asm(void);
- asm(".globl gs_handler_asm\n"
- "gs_handler_asm:\n"
- " lgr %r14,%r15\n" /* Save current stack address in r14 */
- " aghi %r15,-320\n" /* Allocate stack frame */
- " stmg %r0,%r13,192(%r15)\n" /* Store regs to save area */
- " stg %r14,312(%r15)\n"
- " la %r2," xstr(STACK_FRAME_SIZE) "(%r15) \n" /* Store gscb address in this_cb */
- " .insn rxy,0xe30000000049,0," xstr(STACK_FRAME_SIZE) "(%r15)\n" /* stgsc */
- " lg %r14,24(%r2)\n" /* Get GSEPLA from GSCB*/
- " lg %r14,40(%r14)\n" /* Get GSERA from GSEPL*/
- " stg %r14,304(%r15)\n" /* Store GSERA in r14 of reg save area */
- " brasl %r14,gs_handler\n" /* Jump to gs_handler */
- " lmg %r0,%r15,192(%r15)\n" /* Restore regs */
- " aghi %r14, 6\n" /* Add lgg instr len to GSERA */
- " br %r14\n" /* Jump to next instruction after lgg */
- " .size gs_handler_asm,.-gs_handler_asm\n");
+ asm ( ".macro STGSC args:vararg\n"
+ " .insn rxy,0xe30000000049,\\args\n"
+ " .endm\n"
+ " .globl gs_handler_asm\n"
+ "gs_handler_asm:\n"
+ " lgr %r14,%r15\n" /* Save current stack address in r14 */
+ ".Lgs_handler_frame = 16*8+32+" xstr(STACK_FRAME_SIZE) "\n"
+ " aghi %r15,-(.Lgs_handler_frame)\n" /* Allocate stack frame */
+ " stmg %r0,%r13,192(%r15)\n" /* Store regs to save area */
+ " stg %r14,312(%r15)\n"
+ " la %r2," xstr(STACK_FRAME_SIZE) "(%r15)\n" /* Store gscb address in this_cb */
+ " STGSC %r0," xstr(STACK_FRAME_SIZE) "(%r15)\n"
+ " lg %r14,24(%r2)\n" /* Get GSEPLA from GSCB*/
+ " lg %r14,40(%r14)\n" /* Get GSERA from GSEPL*/
+ " stg %r14,304(%r15)\n" /* Store GSERA in r14 of reg save area */
+ " brasl %r14,gs_handler\n" /* Jump to gs_handler */
+ " lmg %r0,%r15,192(%r15)\n" /* Restore regs */
+ " aghi %r14, 6\n" /* Add lgg instr len to GSERA */
+ " br %r14\n" /* Jump to next instruction after lgg */
+ ".size gs_handler_asm,.-gs_handler_asm\n"
+ );
void gs_handler(struct gs_cb *this_cb)
{
