From: Mao Minkai maominkai@wxiat.com
Sunway inclusion category: performance bugzilla: https://gitee.com/openeuler/kernel/issues/I56XPR
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Use jump label instead of normal if-else statement for running modes to improve performance.
Signed-off-by: Mao Minkai maominkai@wxiat.com
Signed-off-by: Gu Zitao guzitao@wxiat.com Acked-by: Xie XiuQi xiexiuqi@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- arch/sw_64/include/asm/hw_init.h | 26 +++++++------------------- arch/sw_64/kernel/setup.c | 19 +++++++++++++++---- 2 files changed, 22 insertions(+), 23 deletions(-)
diff --git a/arch/sw_64/include/asm/hw_init.h b/arch/sw_64/include/asm/hw_init.h index 9a56590ef653..f3d75e0fda7a 100644 --- a/arch/sw_64/include/asm/hw_init.h +++ b/arch/sw_64/include/asm/hw_init.h @@ -2,6 +2,7 @@ #ifndef _ASM_SW64_HW_INIT_H #define _ASM_SW64_HW_INIT_H #include <linux/numa.h> +#include <linux/jump_label.h>
#define MMSIZE __va(0x2040)
@@ -96,26 +97,13 @@ static inline bool icache_is_vivt_no_ictag(void) return (cpu_desc.arch_var == 0x3 && cpu_desc.arch_rev == 0x1); }
-enum RUNMODE { - HOST_MODE = 0, - GUEST_MODE = 1, - EMUL_MODE = 2, -}; +DECLARE_STATIC_KEY_TRUE(run_mode_host_key); +DECLARE_STATIC_KEY_FALSE(run_mode_guest_key); +DECLARE_STATIC_KEY_FALSE(run_mode_emul_key);
-static inline bool is_in_host(void) -{ - return !cpu_desc.run_mode; -} - -static inline bool is_in_guest(void) -{ - return cpu_desc.run_mode == GUEST_MODE; -} - -static inline bool is_guest_or_emul(void) -{ - return !!cpu_desc.run_mode; -} +#define is_in_host() static_branch_likely(&run_mode_host_key) +#define is_in_guest() static_branch_unlikely(&run_mode_guest_key) +#define is_guest_or_emul() !static_branch_likely(&run_mode_host_key)
#define CPU_SW3231 0x31 #define CPU_SW831 0x32 diff --git a/arch/sw_64/kernel/setup.c b/arch/sw_64/kernel/setup.c index 4f735f44ccc3..27f59fe0d1b1 100644 --- a/arch/sw_64/kernel/setup.c +++ b/arch/sw_64/kernel/setup.c @@ -133,6 +133,9 @@ static struct resource bss_resource = { struct cpuinfo_sw64 cpu_data[NR_CPUS]; EXPORT_SYMBOL(cpu_data);
+DEFINE_STATIC_KEY_TRUE(run_mode_host_key); +DEFINE_STATIC_KEY_FALSE(run_mode_guest_key); +DEFINE_STATIC_KEY_FALSE(run_mode_emul_key); struct cpu_desc_t cpu_desc; struct socket_desc_t socket_desc[MAX_NUMSOCKETS]; int memmap_nr; @@ -639,10 +642,18 @@ static void __init setup_cpu_info(void) cpu_desc.arch_rev = CPUID_ARCH_REV(val); cpu_desc.pa_bits = CPUID_PA_BITS(val); cpu_desc.va_bits = CPUID_VA_BITS(val); - cpu_desc.run_mode = HOST_MODE;
- if (*(unsigned long *)MMSIZE) - cpu_desc.run_mode = GUEST_MODE; + if (*(unsigned long *)MMSIZE) { + pr_info("run mode: guest\n"); + static_branch_disable(&run_mode_host_key); + static_branch_enable(&run_mode_guest_key); + static_branch_disable(&run_mode_emul_key); + } else { + pr_info("run mode: host\n"); + static_branch_enable(&run_mode_host_key); + static_branch_disable(&run_mode_guest_key); + static_branch_disable(&run_mode_emul_key); + }
for (i = 0; i < VENDOR_ID_MAX; i++) { val = cpuid(GET_VENDOR_ID, i); @@ -747,6 +758,7 @@ void __init sw64_kvm_reserve(void) void __init setup_arch(char **cmdline_p) { + jump_label_init(); setup_cpu_info(); sw64_chip->fixup(); sw64_chip_init->fixup(); @@ -754,7 +766,6 @@ setup_arch(char **cmdline_p) show_socket_mem_layout(); sw64_chip_init->early_init.setup_core_start(&core_start);
- jump_label_init(); setup_sched_clock(); #ifdef CONFIG_GENERIC_SCHED_CLOCK sw64_sched_clock_init();