runtime/pprof, syscall: report MaxRSS on all unix platforms

All unix platforms currently supported by Go provide the getrusage
syscall. On aix and solaris the Getrusage syscall wrapper is not
available yet, so add and use it to report MaxRSS in memory profiles.

Change-Id: Ie880a3058171031fd2e12ccf9adfb85ce18858b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/391434
Trust: Tobias Klauser <[email protected]>
Run-TryBot: Tobias Klauser <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Michael Pratt <[email protected]>
Trust: Michael Pratt <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>

src/runtime/pprof/pprof_norusage.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build !darwin && !linux
+//go:build !aix && !darwin && !dragonfly && !freebsd && !linux && !netbsd && !openbsd && !solaris
 
 package pprof
 

src/runtime/pprof/pprof_rusage.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build darwin || linux
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
 
 package pprof
 
@@ -17,10 +17,12 @@ import (
 func addMaxRSS(w io.Writer) {
 	var rssToBytes uintptr
 	switch runtime.GOOS {
-	case "linux", "android":
+	case "aix", "android", "dragonfly", "freebsd", "linux", "netbsd", "openbsd":
 		rssToBytes = 1024
 	case "darwin", "ios":
 		rssToBytes = 1
+	case "illumos", "solaris":
+		rssToBytes = uintptr(syscall.Getpagesize())
 	default:
 		panic("unsupported OS")
 	}

src/runtime/pprof/rusage_test.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build darwin || freebsd || linux || netbsd || openbsd
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
 
 package pprof
 

src/syscall/syscall_aix.go

@@ -594,6 +594,7 @@ func PtraceDetach(pid int) (err error) { return ptrace64(PT_DETACH, int64(pid),
 //sys	Getppid() (ppid int)
 //sys	Getpriority(which int, who int) (n int, err error)
 //sysnb	Getrlimit(which int, lim *Rlimit) (err error)
+//sysnb	Getrusage(who int, rusage *Rusage) (err error)
 //sysnb	Getuid() (uid int)
 //sys	Kill(pid int, signum Signal) (err error)
 //sys	Lchown(path string, uid int, gid int) (err error)

src/syscall/syscall_solaris.go

@@ -421,6 +421,7 @@ func sendmsgN(fd int, p, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags i
 //sys	Getppid() (ppid int)
 //sys	Getpriority(which int, who int) (n int, err error)
 //sysnb	Getrlimit(which int, lim *Rlimit) (err error)
+//sysnb	Getrusage(who int, rusage *Rusage) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
 //sysnb	Getuid() (uid int)
 //sys	Kill(pid int, signum Signal) (err error)