ARC: pt_regs update : Remove unused gutter at start of pt_regs

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Vineet Gupta 2013-05-28 09:43:17 +05:30
parent 283237a04f
commit 2fa919045b
4 changed files with 15 additions and 26 deletions
arch/arc
include
kernel

View File

@ -432,9 +432,6 @@
st.a r9, [sp, -4]
lr r9, [erbta]
st.a r9, [sp, -4]
/* move up by 1 word to "create" pt_regs->"stack_place_holder" */
sub sp, sp, 4
.endm
/*--------------------------------------------------------------
@ -474,9 +471,6 @@
* by hardware and that is not good.
*-------------------------------------------------------------*/
.macro RESTORE_ALL_SYS
add sp, sp, 4 /* hop over unused "pt_regs->stack_place_holder" */
ld.ab r9, [sp, 4]
sr r9, [erbta]
ld.ab r9, [sp, 4]
@ -530,9 +524,6 @@
st.a r9, [sp, -4]
lr r9, [bta_l1]
st.a r9, [sp, -4]
/* move up by 1 word to "create" pt_regs->"stack_place_holder" */
sub sp, sp, 4
.endm
.macro SAVE_ALL_INT2
@ -561,9 +552,6 @@
st.a r9, [sp, -4]
lr r9, [bta_l2]
st.a r9, [sp, -4]
/* move up by 1 word to "create" pt_regs->"stack_place_holder" */
sub sp, sp, 4
.endm
/*--------------------------------------------------------------
@ -577,8 +565,6 @@
*-------------------------------------------------------------*/
.macro RESTORE_ALL_INT1
add sp, sp, 4 /* hop over unused "pt_regs->stack_place_holder" */
ld.ab r9, [sp, 4] /* Actual reg file */
sr r9, [bta_l1]
ld.ab r9, [sp, 4]
@ -601,8 +587,6 @@
.endm
.macro RESTORE_ALL_INT2
add sp, sp, 4 /* hop over unused "pt_regs->stack_place_holder" */
ld.ab r9, [sp, 4]
sr r9, [bta_l2]
ld.ab r9, [sp, 4]

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@ -17,12 +17,6 @@
/* THE pt_regs: Defines how regs are saved during entry into kernel */
struct pt_regs {
/*
* 1 word gutter after reg-file has been saved
* Technically not needed, Since SP always points to a "full" location
* (vs. "empty"). But pt_regs is shared with tools....
*/
long res;
/* Real registers */
long bta; /* bta_l1, bta_l2, erbta */

View File

@ -20,16 +20,19 @@
*
* This is to decouple pt_regs from user-space ABI, to be able to change it
* w/o affecting the ABI.
* Although the layout (initial padding) is similar to pt_regs to have some
* optimizations when copying pt_regs to/from user_regs_struct.
*
* The intermediate pad,pad2 are relics of initial layout based on pt_regs
* for optimizations when copying pt_regs to/from user_regs_struct.
* We no longer need them, but can't be changed as they are part of ABI now.
*
* Also, sigcontext only care about the scratch regs as that is what we really
* save/restore for signal handling.
* save/restore for signal handling. However gdb also uses the same struct
* hence callee regs need to be in there too.
*/
struct user_regs_struct {
long pad;
struct {
long pad;
long bta, lp_start, lp_end, lp_count;
long status32, ret, blink, fp, gp;
long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0;

View File

@ -40,6 +40,13 @@ static int genregs_get(struct task_struct *target,
offsetof(struct user_regs_struct, LOC), \
offsetof(struct user_regs_struct, LOC) + 4);
#define REG_O_ZERO(LOC) \
if (!ret) \
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, \
offsetof(struct user_regs_struct, LOC), \
offsetof(struct user_regs_struct, LOC) + 4);
REG_O_ZERO(pad);
REG_O_CHUNK(scratch, callee, ptregs);
REG_O_CHUNK(callee, efa, cregs);
REG_O_CHUNK(efa, stop_pc, &target->thread.fault_address);
@ -88,6 +95,7 @@ static int genregs_set(struct task_struct *target,
offsetof(struct user_regs_struct, LOC), \
offsetof(struct user_regs_struct, LOC) + 4);
REG_IGNORE_ONE(pad);
/* TBD: disallow updates to STATUS32, orig_r8 etc*/
REG_IN_CHUNK(scratch, callee, ptregs); /* pt_regs[bta..orig_r8] */
REG_IN_CHUNK(callee, efa, cregs); /* callee_regs[r25..r13] */