[PATCH v4 2/2] powerpc/irq: inline call_do_irq() and call_do_softirq()
From: Christophe Leroy <hidden>
Date: 2019-10-10 05:36:37
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
call_do_irq() and call_do_softirq() are quite similar on PPC32 and PPC64 and are simple enough to be worth inlining. Inlining them avoids an mflr/mtlr pair plus a save/reload on stack. This is inspired from S390 arch. Several other arches do more or less the same. The way sparc arch does seems odd thought. Signed-off-by: Christophe Leroy <redacted> Reviewed-by: Segher Boessenkool <redacted> --- v2: no change. v3: no change. v4: - comment reminding the purpose of the inline asm block. - added r2 as clobbered reg --- arch/powerpc/include/asm/irq.h | 2 -- arch/powerpc/kernel/irq.c | 32 ++++++++++++++++++++++++++++++++ arch/powerpc/kernel/misc_32.S | 25 ------------------------- arch/powerpc/kernel/misc_64.S | 22 ---------------------- 4 files changed, 32 insertions(+), 49 deletions(-)
diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
index 0c6469983c66..10476d5283dc 100644
--- a/arch/powerpc/include/asm/irq.h
+++ b/arch/powerpc/include/asm/irq.h@@ -57,8 +57,6 @@ extern void *mcheckirq_ctx[NR_CPUS]; extern void *hardirq_ctx[NR_CPUS]; extern void *softirq_ctx[NR_CPUS]; -void call_do_softirq(void *sp); -void call_do_irq(struct pt_regs *regs, void *sp); extern void do_IRQ(struct pt_regs *regs); extern void __init init_IRQ(void); extern void __do_irq(struct pt_regs *regs);
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 04204be49577..d62fe18405a0 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c@@ -642,6 +642,22 @@ void __do_irq(struct pt_regs *regs) irq_exit(); } +static inline void call_do_irq(struct pt_regs *regs, void *sp) +{ + register unsigned long r3 asm("r3") = (unsigned long)regs; + + /* Temporarily switch r1 to sp, call __do_irq() then restore r1 */ + asm volatile( + " "PPC_STLU" 1, %2(%1);\n" + " mr 1, %1;\n" + " bl %3;\n" + " "PPC_LL" 1, 0(1);\n" : + "+r"(r3) : + "b"(sp), "i"(THREAD_SIZE - STACK_FRAME_OVERHEAD), "i"(__do_irq) : + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", "cr7", + "r0", "r2", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12"); +} + void do_IRQ(struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs);
@@ -686,6 +702,22 @@ void *mcheckirq_ctx[NR_CPUS] __read_mostly; void *softirq_ctx[NR_CPUS] __read_mostly; void *hardirq_ctx[NR_CPUS] __read_mostly; +static inline void call_do_softirq(const void *sp) +{ + register unsigned long ret asm("r3"); + + /* Temporarily switch r1 to sp, call __do_softirq() then restore r1 */ + asm volatile( + " "PPC_STLU" 1, %2(%1);\n" + " mr 1, %1;\n" + " bl %3;\n" + " "PPC_LL" 1, 0(1);\n" : + "=r"(ret) : + "b"(sp), "i"(THREAD_SIZE - STACK_FRAME_OVERHEAD), "i"(__do_softirq) : + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", "cr7", + "r0", "r2", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12"); +} + void do_softirq_own_stack(void) { void *irqsp = softirq_ctx[smp_processor_id()];
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index a5422f7782b3..307307b57743 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S@@ -33,31 +33,6 @@ .text -_GLOBAL(call_do_softirq) - mflr r0 - stw r0,4(r1) - stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3) - mr r1,r3 - bl __do_softirq - lwz r1,0(r1) - lwz r0,4(r1) - mtlr r0 - blr - -/* - * void call_do_irq(struct pt_regs *regs, void *sp); - */ -_GLOBAL(call_do_irq) - mflr r0 - stw r0,4(r1) - stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4) - mr r1,r4 - bl __do_irq - lwz r1,0(r1) - lwz r0,4(r1) - mtlr r0 - blr - /* * This returns the high 64 bits of the product of two 64-bit numbers. */
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index b55a7b4cb543..69fd714a5236 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S@@ -27,28 +27,6 @@ .text -_GLOBAL(call_do_softirq) - mflr r0 - std r0,16(r1) - stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3) - mr r1,r3 - bl __do_softirq - ld r1,0(r1) - ld r0,16(r1) - mtlr r0 - blr - -_GLOBAL(call_do_irq) - mflr r0 - std r0,16(r1) - stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4) - mr r1,r4 - bl __do_irq - ld r1,0(r1) - ld r0,16(r1) - mtlr r0 - blr - .section ".toc","aw" PPC64_CACHES: .tc ppc64_caches[TC],ppc64_caches
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2.13.3