From fa54a981ea7a852c145b05c95abba11e81fc1157 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Thu, 9 Aug 2018 08:14:41 +0000 Subject: [PATCH] powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled The symbol memcpy_nocache_branch defined in order to allow patching of memset function once cache is enabled leads to confusing reports by perf tool. Using the new patch_site functionality solves this issue. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/asm-prototypes.h | 1 + arch/powerpc/kernel/setup_32.c | 7 +++---- arch/powerpc/lib/copy_32.S | 9 ++++++--- 3 files changed, 10 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h index 70fdc5b9b9fb..1f4691ce4126 100644 --- a/arch/powerpc/include/asm/asm-prototypes.h +++ b/arch/powerpc/include/asm/asm-prototypes.h @@ -146,6 +146,7 @@ void _kvmppc_save_tm_pr(struct kvm_vcpu *vcpu, u64 guest_msr); /* Patch sites */ extern s32 patch__call_flush_count_cache; extern s32 patch__flush_count_cache_return; +extern s32 patch__memset_nocache, patch__memcpy_nocache; extern long flush_count_cache; diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c index 0e3743343280..ba969278bf4d 100644 --- a/arch/powerpc/kernel/setup_32.c +++ b/arch/powerpc/kernel/setup_32.c @@ -97,11 +97,10 @@ notrace unsigned long __init early_init(unsigned long dt_ptr) * We do the initial parsing of the flat device-tree and prepares * for the MMU to be fully initialized. */ -extern unsigned int memset_nocache_branch; /* Insn to be replaced by NOP */ - notrace void __init machine_init(u64 dt_ptr) { - unsigned int *addr = &memset_nocache_branch; + unsigned int *addr = (unsigned int *)((unsigned long)&patch__memset_nocache + + patch__memset_nocache); unsigned long insn; /* Configure static keys first, now that we're relocated. */ @@ -110,7 +109,7 @@ notrace void __init machine_init(u64 dt_ptr) /* Enable early debugging if any specified (see udbg.h) */ udbg_early_init(); - patch_instruction((unsigned int *)&memcpy, PPC_INST_NOP); + patch_instruction_site(&patch__memcpy_nocache, PPC_INST_NOP); insn = create_cond_branch(addr, branch_target(addr), 0x820000); patch_instruction(addr, insn); /* replace b by bne cr0 */ diff --git a/arch/powerpc/lib/copy_32.S b/arch/powerpc/lib/copy_32.S index da425bb6b369..ba66846fe973 100644 --- a/arch/powerpc/lib/copy_32.S +++ b/arch/powerpc/lib/copy_32.S @@ -13,6 +13,7 @@ #include #include #include +#include #define COPY_16_BYTES \ lwz r7,4(r4); \ @@ -107,8 +108,8 @@ _GLOBAL(memset) * Skip optimised bloc until cache is enabled. Will be replaced * by 'bne' during boot to use normal procedure if r4 is not zero */ -_GLOBAL(memset_nocache_branch) - b 2f +5: b 2f + patch_site 5b, patch__memset_nocache clrlwi r7,r6,32-LG_CACHELINE_BYTES add r8,r7,r5 @@ -168,7 +169,9 @@ _GLOBAL(memmove) /* fall through */ _GLOBAL(memcpy) - b generic_memcpy +1: b generic_memcpy + patch_site 1b, patch__memcpy_nocache + add r7,r3,r5 /* test if the src & dst overlap */ add r8,r4,r5 cmplw 0,r4,r7 -- 2.45.2