3.16.68-rc1 review patch. If anyone has any objections, please let me know.
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From: Peter Zijlstra peterz@infradead.org
commit 76b235c6bcb16062d663e2ee96db0b69f2e6bc14 upstream.
Since we've already stepped away from ENABLE is a JMP and DISABLE is a NOP with the branch_default bits, and are going to make it even worse, rename it to make it all clearer.
This way we don't mix multiple levels of logic attributes, but have a plain 'physical' name for what the current instruction patching status of a jump label is.
This is a first step in removing the naming confusion that has led to a stream of avoidable bugs such as:
a833581e372a ("x86, perf: Fix static_key bug in load_mm_cr4()")
Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Cc: Andrew Morton akpm@linux-foundation.org Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Paul E. McKenney paulmck@linux.vnet.ibm.com Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: linux-kernel@vger.kernel.org [ Beefed up the changelog. ] Signed-off-by: Ingo Molnar mingo@kernel.org [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- arch/arm/kernel/jump_label.c | 2 +- arch/arm64/kernel/jump_label.c | 2 +- arch/mips/kernel/jump_label.c | 2 +- arch/powerpc/kernel/jump_label.c | 2 +- arch/s390/kernel/jump_label.c | 2 +- arch/sparc/kernel/jump_label.c | 2 +- arch/x86/kernel/jump_label.c | 2 +- include/linux/jump_label.h | 4 ++-- kernel/jump_label.c | 18 +++++++++--------- 9 files changed, 18 insertions(+), 18 deletions(-)
--- a/arch/arm/kernel/jump_label.c +++ b/arch/arm/kernel/jump_label.c @@ -13,7 +13,7 @@ static void __arch_jump_label_transform( void *addr = (void *)entry->code; unsigned int insn;
- if (type == JUMP_LABEL_ENABLE) + if (type == JUMP_LABEL_JMP) insn = arm_gen_branch(entry->code, entry->target); else insn = arm_gen_nop(); --- a/arch/arm64/kernel/jump_label.c +++ b/arch/arm64/kernel/jump_label.c @@ -29,7 +29,7 @@ static void __arch_jump_label_transform( void *addr = (void *)entry->code; u32 insn;
- if (type == JUMP_LABEL_ENABLE) { + if (type == JUMP_LABEL_JMP) { insn = aarch64_insn_gen_branch_imm(entry->code, entry->target, AARCH64_INSN_BRANCH_NOLINK); --- a/arch/mips/kernel/jump_label.c +++ b/arch/mips/kernel/jump_label.c @@ -51,7 +51,7 @@ void arch_jump_label_transform(struct ju /* Target must have the right alignment and ISA must be preserved. */ BUG_ON((e->target & J_ALIGN_MASK) != J_ISA_BIT);
- if (type == JUMP_LABEL_ENABLE) { + if (type == JUMP_LABEL_JMP) { insn.j_format.opcode = J_ISA_BIT ? mm_j32_op : j_op; insn.j_format.target = e->target >> J_RANGE_SHIFT; } else { --- a/arch/powerpc/kernel/jump_label.c +++ b/arch/powerpc/kernel/jump_label.c @@ -17,7 +17,7 @@ void arch_jump_label_transform(struct ju { u32 *addr = (u32 *)(unsigned long)entry->code;
- if (type == JUMP_LABEL_ENABLE) + if (type == JUMP_LABEL_JMP) patch_branch(addr, entry->target, 0); else patch_instruction(addr, PPC_INST_NOP); --- a/arch/s390/kernel/jump_label.c +++ b/arch/s390/kernel/jump_label.c @@ -60,7 +60,7 @@ static void __jump_label_transform(struc { struct insn old, new;
- if (type == JUMP_LABEL_ENABLE) { + if (type == JUMP_LABEL_JMP) { jump_label_make_nop(entry, &old); jump_label_make_branch(entry, &new); } else { --- a/arch/sparc/kernel/jump_label.c +++ b/arch/sparc/kernel/jump_label.c @@ -16,7 +16,7 @@ void arch_jump_label_transform(struct ju u32 val; u32 *insn = (u32 *) (unsigned long) entry->code;
- if (type == JUMP_LABEL_ENABLE) { + if (type == JUMP_LABEL_JMP) { s32 off = (s32)entry->target - (s32)entry->code;
#ifdef CONFIG_SPARC64 --- a/arch/x86/kernel/jump_label.c +++ b/arch/x86/kernel/jump_label.c @@ -45,7 +45,7 @@ static void __jump_label_transform(struc const unsigned char default_nop[] = { STATIC_KEY_INIT_NOP }; const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5];
- if (type == JUMP_LABEL_ENABLE) { + if (type == JUMP_LABEL_JMP) { if (init) { /* * Jump label is enabled for the first time. --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -86,8 +86,8 @@ struct static_key { #ifndef __ASSEMBLY__
enum jump_label_type { - JUMP_LABEL_DISABLE = 0, - JUMP_LABEL_ENABLE, + JUMP_LABEL_NOP = 0, + JUMP_LABEL_JMP, };
struct module; --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -65,9 +65,9 @@ void static_key_slow_inc(struct static_k jump_label_lock(); if (atomic_read(&key->enabled) == 0) { if (!jump_label_get_branch_default(key)) - jump_label_update(key, JUMP_LABEL_ENABLE); + jump_label_update(key, JUMP_LABEL_JMP); else - jump_label_update(key, JUMP_LABEL_DISABLE); + jump_label_update(key, JUMP_LABEL_NOP); } atomic_inc(&key->enabled); jump_label_unlock(); @@ -88,9 +88,9 @@ static void __static_key_slow_dec(struct schedule_delayed_work(work, rate_limit); } else { if (!jump_label_get_branch_default(key)) - jump_label_update(key, JUMP_LABEL_DISABLE); + jump_label_update(key, JUMP_LABEL_NOP); else - jump_label_update(key, JUMP_LABEL_ENABLE); + jump_label_update(key, JUMP_LABEL_JMP); } jump_label_unlock(); } @@ -191,9 +191,9 @@ static enum jump_label_type jump_label_t bool state = static_key_enabled(key);
if ((!true_branch && state) || (true_branch && !state)) - return JUMP_LABEL_ENABLE; + return JUMP_LABEL_JMP;
- return JUMP_LABEL_DISABLE; + return JUMP_LABEL_NOP; }
void __init jump_label_init(void) @@ -283,7 +283,7 @@ void jump_label_apply_nops(struct module return;
for (iter = iter_start; iter < iter_stop; iter++) { - arch_jump_label_transform_static(iter, JUMP_LABEL_DISABLE); + arch_jump_label_transform_static(iter, JUMP_LABEL_NOP); } }
@@ -325,8 +325,8 @@ static int jump_label_add_module(struct jlm->next = key->next; key->next = jlm;
- if (jump_label_type(key) == JUMP_LABEL_ENABLE) - __jump_label_update(key, iter, iter_stop, JUMP_LABEL_ENABLE); + if (jump_label_type(key) == JUMP_LABEL_JMP) + __jump_label_update(key, iter, iter_stop, JUMP_LABEL_JMP); }
return 0;