@@ -190,12 +190,13 @@ _GLOBAL(_switch)
mflr r0
std r0,16(r1)
stdu r1,-SWITCH_FRAME_SIZE(r1)
+ std r1,KSP(r3) /* Set old stack pointer */
/* r3-r13 are caller saved -- Cort */
SAVE_NVGPRS(r1)
std r0,_NIP(r1) /* Return to switch caller */
- mfcr r23
- std r23,_CCR(r1)
- std r1,KSP(r3) /* Set old stack pointer */
+ mfcr r0
+ stw r0,_CCR(r1)
+ ld r8,KSP(r4) /* Load new stack pointer */
kuap_check_amr r9, r10
@@ -232,14 +233,20 @@ _GLOBAL(_switch)
DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r6)
#endif
- addi r6,r4,-THREAD /* Convert THREAD to 'current' */
- std r6,PACACURRENT(r13) /* Set new 'current' */
+ addi r3,r3,-THREAD /* old thread -> task_struct for return value */
+ addi r6,r4,-THREAD /* new thread -> task_struct */
+ std r6,PACACURRENT(r13) /* Set new task_struct to 'current' */
#if defined(CONFIG_STACKPROTECTOR)
ld r6, TASK_CANARY(r6)
std r6, PACA_CANARY(r13)
#endif
-
- ld r8,KSP(r4) /* new stack pointer */
+ /* Set the new PACAKSAVE */
+ clrrdi r7, r8, THREAD_SHIFT /* base of new stack */
+ /* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE
+ because we don't need to leave the 288-byte ABI gap at the
+ top of the kernel stack. */
+ addi r7,r7,THREAD_SIZE-SWITCH_FRAME_SIZE
+ std r7,PACAKSAVE(r13)
#ifdef CONFIG_PPC_64S_HASH_MMU
BEGIN_MMU_FTR_SECTION
@@ -247,12 +254,6 @@ BEGIN_MMU_FTR_SECTION
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
#endif
- clrrdi r7, r8, THREAD_SHIFT /* base of new stack */
- /* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE
- because we don't need to leave the 288-byte ABI gap at the
- top of the kernel stack. */
- addi r7,r7,THREAD_SIZE-SWITCH_FRAME_SIZE
-
/*
* PMU interrupts in radix may come in here. They will use r1, not
* PACAKSAVE, so this stack switch will not cause a problem. They
@@ -262,18 +263,15 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
* active on the new CPU, will order those stores.
*/
mr r1,r8 /* start using new stack pointer */
- std r7,PACAKSAVE(r13)
- ld r6,_CCR(r1)
- mtcrf 0xFF,r6
+ lwz r0,_CCR(r1)
+ mtcrf 0xFF,r0
/* r3-r13 are destroyed -- Cort */
REST_NVGPRS(r1)
- /* convert old thread to its task_struct for return value */
- addi r3,r3,-THREAD
- ld r7,_NIP(r1) /* Return to _switch caller in new task */
- mtlr r7
+ ld r0,_NIP(r1) /* Return to _switch caller in new task */
+ mtlr r0
addi r1,r1,SWITCH_FRAME_SIZE
blr
More some 64-bit specifics out from the function epilogue and rearrange this to be a bit neater, use 32-bit mem ops for CR save/restore, and change some register numbers. This is preparation to consolidate 32-bit and 64-bit switch code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/kernel/entry_64.S | 38 ++++++++++++++++------------------ 1 file changed, 18 insertions(+), 20 deletions(-)