ref: 69e28c6513866152265fb11c2424afe69f0323d3
parent: 17a92f3995976b5d7618d1a2442e0028c1b192de
author: cinap_lenrek <[email protected]>
date: Sat Feb 29 16:06:45 EST 2020
kernel: simplify exec() progarg[0] can be assigned to elem directly as it is a copy in kernel memory, so the char proelem[64] buffer is not neccesary. do the close-on-exit outside of the segment lock. there is no reason to keep the segment table locked.
--- a/sys/src/9/port/sysproc.c
+++ b/sys/src/9/port/sysproc.c
@@ -271,20 +271,20 @@
uintptr
sysexec(va_list list)
{- Segment *s, *ts;
- int i;
- Chan *tc;
- char **argv, **argp, **argp0;
- char *a, *e, *charp, *args, *file, *file0;
- char *progarg[sizeof(Exec)/2+1], *elem, progelem[64];
- ulong magic, ssize, nargs, nbytes, n;
- uintptr t, d, b, entry, bssend, text, data, bss, tstk, align;
- int indir;
Exec exec;
char line[sizeof(Exec)];
- Fgrp *f;
+ char *progarg[sizeof(line)/2+1];
+ volatile char *args, *elem, *file0;
+ char **argv, **argp, **argp0;
+ char *a, *e, *charp, *file;
+ int i, n, indir;
+ ulong magic, ssize, nargs, nbytes;
+ uintptr t, d, b, entry, bssend, text, data, bss, tstk, align;
+ Segment *s, *ts;
Image *img;
Tos *tos;
+ Chan *tc;
+ Fgrp *f;
args = elem = nil;
file0 = va_arg(list, char*);
@@ -352,12 +352,11 @@
* Process #! /bin/sh args ...
*/
memmove(line, &exec, n);
- if(indir || line[0]!='#' || line[1]!='!')
+ if(line[0]!='#' || line[1]!='!' || indir++)
error(Ebadexec);
n = shargs(line, n, progarg);
if(n < 1)
error(Ebadexec);
- indir = 1;
/*
* First arg becomes complete file name
*/
@@ -365,10 +364,7 @@
progarg[n] = nil;
argp0++;
file = progarg[0];
- if(strlen(elem) >= sizeof progelem)
- error(Ebadexec);
- strcpy(progelem, elem);
- progarg[0] = progelem;
+ progarg[0] = elem;
poperror();
cclose(tc);
}
@@ -513,14 +509,6 @@
}
}
- /*
- * Close on exec
- */
- if((f = up->fgrp) != nil) {- for(i=0; i<=f->maxfd; i++)
- fdclose(i, CCEXEC);
- }
-
/* Text. Shared. Attaches to cache image if possible */
/* attachimage returns a locked cache image */
img = attachimage(SG_TEXT | SG_RONLY, tc, UTZERO, (t-UTZERO)>>PGSHIFT);
@@ -557,11 +545,20 @@
poperror(); /* seglock */
/*
+ * Close on exec
+ */
+ if((f = up->fgrp) != nil) {+ for(i=0; i<=f->maxfd; i++)
+ fdclose(i, CCEXEC);
+ }
+
+ /*
* '/' processes are higher priority (hack to make /ip more responsive).
*/
if(devtab[tc->type]->dc == L'/')
up->basepri = PriRoot;
up->priority = up->basepri;
+
poperror(); /* tc */
cclose(tc);
poperror(); /* file0 */