From d22883d715440f743ab427396f0a87b72e724d18 Mon Sep 17 00:00:00 2001 From: "Jason A. Harmening" Date: Tue, 9 Mar 2021 20:43:01 -0800 Subject: [PATCH] Remove PCPU_INC e4b8deb22227 removed the last in-tree uses of PCPU_INC(). Its potential benefit is also practically nonexistent. Non-x86 platforms already implement it as PCPU_ADD(..., 1), and according to [0] there are no recent x86 processors for which the 'inc' instruction provides a performance benefit over the equivalent memory-operand form of the 'add' instruction. The only remaining benefit of 'inc' is smaller instruction size, which in this case is inconsequential given the limited number of per-CPU data consumers. [0]: https://www.agner.org/optimize/instruction_tables.pdf Reviewed by: kib Differential Revision: https://reviews.freebsd.org/D29308 --- sys/amd64/include/pcpu.h | 29 ----------------------------- sys/arm/include/pcpu.h | 1 - sys/arm64/include/pcpu.h | 1 - sys/i386/include/pcpu.h | 24 ------------------------ sys/mips/include/pcpu.h | 1 - sys/powerpc/include/pcpu.h | 1 - sys/riscv/include/pcpu.h | 1 - 7 files changed, 58 deletions(-) diff --git a/sys/amd64/include/pcpu.h b/sys/amd64/include/pcpu.h index 6326fbdae0be..dc99d4249bd2 100644 --- a/sys/amd64/include/pcpu.h +++ b/sys/amd64/include/pcpu.h @@ -179,34 +179,6 @@ _Static_assert(sizeof(struct monitorbuf) == 128, "2x cache line"); *__PCPU_PTR(name) += __val; \ } while (0) -/* - * Increments the value of the per-cpu counter name. The implementation - * must be atomic with respect to interrupts. - */ -#define __PCPU_INC(name) do { \ - CTASSERT(sizeof(__pcpu_type(name)) == 1 || \ - sizeof(__pcpu_type(name)) == 2 || \ - sizeof(__pcpu_type(name)) == 4 || \ - sizeof(__pcpu_type(name)) == 8); \ - if (sizeof(__pcpu_type(name)) == 1) { \ - __asm __volatile("incb %%gs:%0" \ - : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\ - : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\ - } else if (sizeof(__pcpu_type(name)) == 2) { \ - __asm __volatile("incw %%gs:%0" \ - : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\ - : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\ - } else if (sizeof(__pcpu_type(name)) == 4) { \ - __asm __volatile("incl %%gs:%0" \ - : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\ - : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\ - } else if (sizeof(__pcpu_type(name)) == 8) { \ - __asm __volatile("incq %%gs:%0" \ - : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\ - : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\ - } \ -} while (0) - /* * Sets the value of the per-cpu variable name to value val. */ @@ -239,7 +211,6 @@ _Static_assert(sizeof(struct monitorbuf) == 128, "2x cache line"); #define PCPU_GET(member) __PCPU_GET(pc_ ## member) #define PCPU_ADD(member, val) __PCPU_ADD(pc_ ## member, val) -#define PCPU_INC(member) __PCPU_INC(pc_ ## member) #define PCPU_PTR(member) __PCPU_PTR(pc_ ## member) #define PCPU_SET(member, val) __PCPU_SET(pc_ ## member, val) diff --git a/sys/arm/include/pcpu.h b/sys/arm/include/pcpu.h index 4d609b10bf73..2353b1d06b17 100644 --- a/sys/arm/include/pcpu.h +++ b/sys/arm/include/pcpu.h @@ -136,7 +136,6 @@ set_tls(void *tls) #define PCPU_GET(member) (get_pcpu()->pc_ ## member) #define PCPU_ADD(member, value) (get_pcpu()->pc_ ## member += (value)) -#define PCPU_INC(member) PCPU_ADD(member, 1) #define PCPU_PTR(member) (&get_pcpu()->pc_ ## member) #define PCPU_SET(member,value) (get_pcpu()->pc_ ## member = (value)) diff --git a/sys/arm64/include/pcpu.h b/sys/arm64/include/pcpu.h index ce4dc46e1609..09f6361c651c 100644 --- a/sys/arm64/include/pcpu.h +++ b/sys/arm64/include/pcpu.h @@ -73,7 +73,6 @@ get_curthread(void) #define PCPU_GET(member) (pcpup->pc_ ## member) #define PCPU_ADD(member, value) (pcpup->pc_ ## member += (value)) -#define PCPU_INC(member) PCPU_ADD(member, 1) #define PCPU_PTR(member) (&pcpup->pc_ ## member) #define PCPU_SET(member,value) (pcpup->pc_ ## member = (value)) diff --git a/sys/i386/include/pcpu.h b/sys/i386/include/pcpu.h index 9e65d179dc36..a4c7968ea85f 100644 --- a/sys/i386/include/pcpu.h +++ b/sys/i386/include/pcpu.h @@ -169,29 +169,6 @@ _Static_assert(sizeof(struct monitorbuf) == 128, "2x cache line"); *__PCPU_PTR(name) += __val; \ } while (0) -/* - * Increments the value of the per-cpu counter name. The implementation - * must be atomic with respect to interrupts. - */ -#define __PCPU_INC(name) do { \ - CTASSERT(sizeof(__pcpu_type(name)) == 1 || \ - sizeof(__pcpu_type(name)) == 2 || \ - sizeof(__pcpu_type(name)) == 4); \ - if (sizeof(__pcpu_type(name)) == 1) { \ - __asm __volatile("incb %%fs:%0" \ - : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\ - : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\ - } else if (sizeof(__pcpu_type(name)) == 2) { \ - __asm __volatile("incw %%fs:%0" \ - : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\ - : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\ - } else if (sizeof(__pcpu_type(name)) == 4) { \ - __asm __volatile("incl %%fs:%0" \ - : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\ - : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\ - } \ -} while (0) - /* * Sets the value of the per-cpu variable name to value val. */ @@ -224,7 +201,6 @@ _Static_assert(sizeof(struct monitorbuf) == 128, "2x cache line"); #define PCPU_GET(member) __PCPU_GET(pc_ ## member) #define PCPU_ADD(member, val) __PCPU_ADD(pc_ ## member, val) -#define PCPU_INC(member) __PCPU_INC(pc_ ## member) #define PCPU_PTR(member) __PCPU_PTR(pc_ ## member) #define PCPU_SET(member, val) __PCPU_SET(pc_ ## member, val) diff --git a/sys/mips/include/pcpu.h b/sys/mips/include/pcpu.h index fea594729e90..879f2d8afb90 100644 --- a/sys/mips/include/pcpu.h +++ b/sys/mips/include/pcpu.h @@ -83,7 +83,6 @@ extern struct pcpu *pcpup; #define PCPU_ADD(member, value) (PCPUP->pc_ ## member += (value)) #define PCPU_GET(member) (PCPUP->pc_ ## member) -#define PCPU_INC(member) PCPU_ADD(member, 1) #define PCPU_PTR(member) (&PCPUP->pc_ ## member) #define PCPU_SET(member,value) (PCPUP->pc_ ## member = (value)) #define PCPU_LAZY_INC(member) (++PCPUP->pc_ ## member) diff --git a/sys/powerpc/include/pcpu.h b/sys/powerpc/include/pcpu.h index 31c4b2c47c70..288e12c1f2ab 100644 --- a/sys/powerpc/include/pcpu.h +++ b/sys/powerpc/include/pcpu.h @@ -168,7 +168,6 @@ __curthread(void) * with respect to preemption. */ #define PCPU_ADD(member, value) (pcpup->pc_ ## member += (value)) -#define PCPU_INC(member) PCPU_ADD(member, 1) #define PCPU_PTR(member) (&pcpup->pc_ ## member) #define PCPU_SET(member,value) (pcpup->pc_ ## member = (value)) diff --git a/sys/riscv/include/pcpu.h b/sys/riscv/include/pcpu.h index 5068596462fc..af5eb6fd5c41 100644 --- a/sys/riscv/include/pcpu.h +++ b/sys/riscv/include/pcpu.h @@ -79,7 +79,6 @@ get_curthread(void) #define PCPU_GET(member) (get_pcpu()->pc_ ## member) #define PCPU_ADD(member, value) (get_pcpu()->pc_ ## member += (value)) -#define PCPU_INC(member) PCPU_ADD(member, 1) #define PCPU_PTR(member) (&get_pcpu()->pc_ ## member) #define PCPU_SET(member,value) (get_pcpu()->pc_ ## member = (value))