syscall: implement EpollCreate using EpollCreate1 on all linux platforms

Most newer architectures (e.g. arm64, riscv64, loong64) don't provide the
epoll_create syscall. Some systems (e.g. Android) block it even if it
were available. In the kernel, the epoll_create syscall is implemented
[1] the same way EpollCreate is implemented in this package for
platforms without the epoll_create syscall. The epoll_create1 syscall is
available since Linux kernel 2.6.27 and the minimum required kernel
version is 2.6.32 since Go 1.18 (see #45964). Thus, avoid the separate
wrapper and consistently implement EpollCreate using EpollCreate1.

[1] https://elixir.bootlin.com/linux/v5.15-rc1/source/fs/eventpoll.c#L2006

The same change was already done in CL 349809 for golang.org/x/sys/unix.

For #45964

Change-Id: I5463b208aa7ae236fa2c175d6d3ec6568f1840b0
Reviewed-on: https://go-review.googlesource.com/c/go/+/411594
Reviewed-by: Bryan Mills <[email protected]>
Auto-Submit: Tobias Klauser <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Run-TryBot: Tobias Klauser <[email protected]>

Author: tklauser

src/syscall/syscall_linux.go

@@ -115,6 +115,13 @@ func Creat(path string, mode uint32) (fd int, err error) {
 	return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode)
 }
 
+func EpollCreate(size int) (fd int, err error) {
+	if size <= 0 {
+		return -1, EINVAL
+	}
+	return EpollCreate1(0)
+}
+
 func isGroupMember(gid int) bool {
 	groups, err := Getgroups()
 	if err != nil {

src/syscall/syscall_linux_386.go

@@ -19,7 +19,6 @@ func setTimeval(sec, usec int64) Timeval {
 // 64-bit file system and 32-bit uid calls
 // (386 default is 32-bit file system and 16-bit uid).
 //sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error) = SYS_FCHOWN32
 //sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
 //sys	fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64

src/syscall/syscall_linux_amd64.go

@@ -7,7 +7,6 @@ package syscall
 const _SYS_setgroups = SYS_SETGROUPS
 
 //sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstat(fd int, stat *Stat_t) (err error)
 //sys	Fstatfs(fd int, buf *Statfs_t) (err error)

src/syscall/syscall_linux_arm.go

@@ -46,7 +46,6 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
 // 64-bit file system and 32-bit uid calls
 // (16-bit uid calls are not always supported in newer kernels)
 //sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error) = SYS_FCHOWN32
 //sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
 //sys	fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64

src/syscall/syscall_linux_arm64.go

@@ -8,13 +8,6 @@ import "unsafe"
 
 const _SYS_setgroups = SYS_SETGROUPS
 
-func EpollCreate(size int) (fd int, err error) {
-	if size <= 0 {
-		return -1, EINVAL
-	}
-	return EpollCreate1(0)
-}
-
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) = SYS_EPOLL_PWAIT
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstat(fd int, stat *Stat_t) (err error)

src/syscall/syscall_linux_loong64.go

@@ -8,13 +8,6 @@ import "unsafe"
 
 const _SYS_setgroups = SYS_SETGROUPS
 
-func EpollCreate(size int) (fd int, err error) {
-	if size <= 0 {
-		return -1, EINVAL
-	}
-	return EpollCreate1(0)
-}
-
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) = SYS_EPOLL_PWAIT
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstatfs(fd int, buf *Statfs_t) (err error)

src/syscall/syscall_linux_mips64x.go

@@ -9,7 +9,6 @@ package syscall
 const _SYS_setgroups = SYS_SETGROUPS
 
 //sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstatfs(fd int, buf *Statfs_t) (err error)
 //sys	fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_NEWFSTATAT

src/syscall/syscall_linux_mipsx.go

@@ -13,7 +13,6 @@ const _SYS_setgroups = SYS_SETGROUPS
 func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err Errno)
 
 //sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64
 //sys	Ftruncate(fd int, length int64) (err error) = SYS_FTRUNCATE64

src/syscall/syscall_linux_ppc64x.go

@@ -9,7 +9,6 @@ package syscall
 const _SYS_setgroups = SYS_SETGROUPS
 
 //sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstat(fd int, stat *Stat_t) (err error)

src/syscall/syscall_linux_riscv64.go

@@ -8,13 +8,6 @@ import "unsafe"
 
 const _SYS_setgroups = SYS_SETGROUPS
 
-func EpollCreate(size int) (fd int, err error) {
-	if size <= 0 {
-		return -1, EINVAL
-	}
-	return EpollCreate1(0)
-}
-
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) = SYS_EPOLL_PWAIT
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstat(fd int, stat *Stat_t) (err error)

src/syscall/syscall_linux_s390x.go

@@ -9,7 +9,6 @@ import "unsafe"
 const _SYS_setgroups = SYS_SETGROUPS
 
 //sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstat(fd int, stat *Stat_t) (err error)