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[newlib-cygwin] Reduce stack pressure throughout Cygwin
- From: Corinna Vinschen <corinna at sourceware dot org>
- To: cygwin-cvs at sourceware dot org
- Date: 20 Jul 2015 09:56:21 -0000
- Subject: [newlib-cygwin] Reduce stack pressure throughout Cygwin
https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=4889f730c1fa5db8cea2780eaa1d2156c92b298a
commit 4889f730c1fa5db8cea2780eaa1d2156c92b298a
Author: Corinna Vinschen <corinna@vinschen.de>
Date: Sun Jul 19 22:38:30 2015 +0200
Reduce stack pressure throughout Cygwin
* dcrt0.cc (initial_env): Reduce size of local path buffers to
PATH_MAX. Allocate debugger_command from process heap.
(init_windows_system_directory): Very early initialize new global
variable global_progname.
* dll_init.cc (dll_list::alloc): Make path buffer static. Explain why.
(dll_list::populate_deps): Use tmp_pathbuf for local path buffer.
* exceptions.cc (debugger_command): Convert to PWCHAR.
(error_start_init): Allocate debugger_command and fill with wide char
strings. Only allocate if NULL.
(try_to_debug): Just check if debugger_command is a NULL pointer to
return. Drop conversion from char to WCHAR and drop local variable
dbg_cmd.
* globals.cc (global_progname): New global variable to store Windows
application path.
* pinfo.cc (pinfo_basic::pinfo_basic): Just copy progname over from
global_progname.
(pinfo::status_exit): Let path_conv create the POSIX path to
avoid local buffer.
* pseudo_reloc.cc (__report_error): Utilize global_progname, drop local
buffer.
* smallprint.cc (__small_vsprintf): Just utilize global_progname for
%P format specifier.
(__small_vswprintf): Ditto.
* strace.cc (PROTECT): Change to reflect x being a pointer. Reformat.
(CHECK): Ditto. Reformat.
(strace::activate): Utilize global_progname, drop local buffer.
Fix formatting.
(strace::vsprntf): Reduce size of local progname buffer to NAME_MAX.
Copy and, if necessary, convert only the last path component to
progname.
(strace_buf_guard): New muto.
(buf): New static pointer.
(strace::vprntf): Use buf under strace_buf_guard lock only. Allocate
buffer space for buf on Windows heap.
* wow64.cc (wow64_respawn_process): Utilize global_progname, drop
local path buffer.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Diff:
---
winsup/cygwin/ChangeLog | 39 ++++++++++++++++++++
winsup/cygwin/dcrt0.cc | 14 +++++--
winsup/cygwin/dll_init.cc | 9 ++++-
winsup/cygwin/exceptions.cc | 38 +++++++++----------
winsup/cygwin/globals.cc | 1 +
winsup/cygwin/pinfo.cc | 12 +++---
winsup/cygwin/pseudo-reloc.cc | 8 ++--
winsup/cygwin/smallprint.cc | 14 ++-----
winsup/cygwin/strace.cc | 85 +++++++++++++++++++++++++------------------
winsup/cygwin/wow64.cc | 6 +--
10 files changed, 141 insertions(+), 85 deletions(-)
diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 4342929..a606cca 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,42 @@
+2015-07-19 Corinna Vinschen <corinna@vinschen.de>
+
+ * dcrt0.cc (initial_env): Reduce size of local path buffers to
+ PATH_MAX. Allocate debugger_command from process heap.
+ (init_windows_system_directory): Very early initialize new global
+ variable global_progname.
+ * dll_init.cc (dll_list::alloc): Make path buffer static. Explain why.
+ (dll_list::populate_deps): Use tmp_pathbuf for local path buffer.
+ * exceptions.cc (debugger_command): Convert to PWCHAR.
+ (error_start_init): Allocate debugger_command and fill with wide char
+ strings. Only allocate if NULL.
+ (try_to_debug): Just check if debugger_command is a NULL pointer to
+ return. Drop conversion from char to WCHAR and drop local variable
+ dbg_cmd.
+ * globals.cc (global_progname): New global variable to store Windows
+ application path.
+ * pinfo.cc (pinfo_basic::pinfo_basic): Just copy progname over from
+ global_progname.
+ (pinfo::status_exit): Let path_conv create the POSIX path to
+ avoid local buffer.
+ * pseudo_reloc.cc (__report_error): Utilize global_progname, drop local
+ buffer.
+ * smallprint.cc (__small_vsprintf): Just utilize global_progname for
+ %P format specifier.
+ (__small_vswprintf): Ditto.
+ * strace.cc (PROTECT): Change to reflect x being a pointer. Reformat.
+ (CHECK): Ditto. Reformat.
+ (strace::activate): Utilize global_progname, drop local buffer.
+ Fix formatting.
+ (strace::vsprntf): Reduce size of local progname buffer to NAME_MAX.
+ Copy and, if necessary, convert only the last path component to
+ progname.
+ (strace_buf_guard): New muto.
+ (buf): New static pointer.
+ (strace::vprntf): Use buf under strace_buf_guard lock only. Allocate
+ buffer space for buf on Windows heap.
+ * wow64.cc (wow64_respawn_process): Utilize global_progname, drop
+ local path buffer.
+
2015-07-18 Corinna Vinschen <corinna@vinschen.de>
* gendef: Remove unused 64 bit versions of __sjfault and __ljfault.
diff --git a/winsup/cygwin/dcrt0.cc b/winsup/cygwin/dcrt0.cc
index 1874fe5..d7f5494 100644
--- a/winsup/cygwin/dcrt0.cc
+++ b/winsup/cygwin/dcrt0.cc
@@ -509,11 +509,11 @@ initial_env ()
_cygwin_testing = 1;
#ifdef DEBUGGING
- char buf[NT_MAX_PATH];
+ char buf[PATH_MAX];
if (GetEnvironmentVariableA ("CYGWIN_DEBUG", buf, sizeof (buf) - 1))
{
- char buf1[NT_MAX_PATH];
- GetModuleFileName (NULL, buf1, NT_MAX_PATH);
+ char buf1[PATH_MAX];
+ GetModuleFileName (NULL, buf1, PATH_MAX);
char *p = strpbrk (buf, ":=");
if (!p)
p = (char *) "gdb.exe -nw";
@@ -521,6 +521,13 @@ initial_env ()
*p++ = '\0';
if (strcasestr (buf1, buf))
{
+ extern PWCHAR debugger_command;
+
+ debugger_command = (PWCHAR) HeapAlloc (GetProcessHeap (), 0,
+ (2 * NT_MAX_PATH + 20)
+ * sizeof (WCHAR));
+ if (!debugger_command)
+ return;
error_start_init (p);
jit_debug = true;
try_to_debug ();
@@ -736,6 +743,7 @@ void
dll_crt0_0 ()
{
wincap.init ();
+ GetModuleFileNameW (NULL, global_progname, NT_MAX_PATH);
child_proc_info = get_cygwin_startup_info ();
init_windows_system_directory ();
initial_env ();
diff --git a/winsup/cygwin/dll_init.cc b/winsup/cygwin/dll_init.cc
index 51ef186..313b0ff 100644
--- a/winsup/cygwin/dll_init.cc
+++ b/winsup/cygwin/dll_init.cc
@@ -25,6 +25,7 @@ details. */
#include <wchar.h>
#include <sys/reent.h>
#include <assert.h>
+#include <tls_pbuf.h>
extern void __stdcall check_sanity_and_sync (per_process *);
@@ -178,7 +179,9 @@ dll_list::find_by_modname (const PWCHAR modname)
dll *
dll_list::alloc (HINSTANCE h, per_process *p, dll_type type)
{
- WCHAR buf[NT_MAX_PATH];
+ /* Called under loader lock conditions so this function can't be called
+ multiple times in parallel. A static buffer is safe. */
+ static WCHAR buf[NT_MAX_PATH];
GetModuleFileNameW (h, buf, NT_MAX_PATH);
PWCHAR name = buf;
if (!wcsncmp (name, L"\\\\?\\", 4))
@@ -264,7 +267,9 @@ dll_list::append (dll* d)
void dll_list::populate_deps (dll* d)
{
- WCHAR wmodname[NT_MAX_PATH];
+ tmp_pathbuf tp;
+
+ PWCHAR wmodname = tp.w_get ();
pefile* pef = (pefile*) d->handle;
PIMAGE_DATA_DIRECTORY dd = pef->idata_dir (IMAGE_DIRECTORY_ENTRY_IMPORT);
/* Annoyance: calling crealloc with a NULL pointer will use the
diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index 0025be6..c4b0761 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -46,7 +46,7 @@ details. */
#define CALL_HANDLER_RETRY_OUTER 10
#define CALL_HANDLER_RETRY_INNER 10
-char debugger_command[2 * NT_MAX_PATH + 20];
+PWCHAR debugger_command;
extern u_char _sigbe;
extern u_char _sigdelayed_end;
@@ -112,18 +112,19 @@ extern "C" void
error_start_init (const char *buf)
{
if (!buf || !*buf)
- {
- debugger_command[0] = '\0';
- return;
- }
-
- char pgm[NT_MAX_PATH];
- if (!GetModuleFileName (NULL, pgm, NT_MAX_PATH))
- strcpy (pgm, "cygwin1.dll");
- for (char *p = strchr (pgm, '\\'); p; p = strchr (p, '\\'))
- *p = '/';
+ return;
+ if (!debugger_command &&
+ !(debugger_command = (PWCHAR) malloc ((2 * NT_MAX_PATH + 20)
+ * sizeof (WCHAR))))
+ return;
- __small_sprintf (debugger_command, "%s \"%s\"", buf, pgm);
+ PWCHAR cp = debugger_command
+ + sys_mbstowcs (debugger_command, NT_MAX_PATH, buf) - 1;
+ cp = wcpcpy (cp, L" \"");
+ wcpcpy (cp, global_progname);
+ for (PWCHAR p = wcschr (cp, L'\\'); p; p = wcschr (p, L'\\'))
+ *p = L'/';
+ wcscat (cp, L"\"");
}
void
@@ -474,9 +475,9 @@ cygwin_stackdump ()
extern "C" int
try_to_debug (bool waitloop)
{
- debug_printf ("debugger_command '%s'", debugger_command);
- if (*debugger_command == '\0')
+ if (!debugger_command)
return 0;
+ debug_printf ("debugger_command '%W'", debugger_command);
if (being_debugged ())
{
extern void break_here ();
@@ -484,8 +485,8 @@ try_to_debug (bool waitloop)
return 0;
}
- __small_sprintf (strchr (debugger_command, '\0'), " %u",
- GetCurrentProcessId ());
+ PWCHAR dbg_end = wcschr (debugger_command, L'\0');
+ __small_swprintf (dbg_end, L" %u", GetCurrentProcessId ());
LONG prio = GetThreadPriority (GetCurrentThread ());
SetThreadPriority (GetCurrentThread (), THREAD_PRIORITY_HIGHEST);
@@ -529,10 +530,8 @@ try_to_debug (bool waitloop)
console_printf ("*** starting debugger for pid %u, tid %u\n",
cygwin_pid (GetCurrentProcessId ()), GetCurrentThreadId ());
BOOL dbg;
- WCHAR dbg_cmd[strlen(debugger_command) + 1];
- sys_mbstowcs (dbg_cmd, strlen(debugger_command) + 1, debugger_command);
dbg = CreateProcessW (NULL,
- dbg_cmd,
+ debugger_command,
NULL,
NULL,
FALSE,
@@ -542,6 +541,7 @@ try_to_debug (bool waitloop)
&si,
&pi);
+ *dbg_end = L'\0';
if (!dbg)
system_printf ("Failed to start debugger, %E");
else
diff --git a/winsup/cygwin/globals.cc b/winsup/cygwin/globals.cc
index 92f9acc..3897419 100644
--- a/winsup/cygwin/globals.cc
+++ b/winsup/cygwin/globals.cc
@@ -31,6 +31,7 @@ UINT windows_system_directory_length;
WCHAR system_wow64_directory[MAX_PATH];
UINT system_wow64_directory_length;
#endif /* !__x86_64__ */
+WCHAR global_progname[NT_MAX_PATH];
/* program exit the program */
diff --git a/winsup/cygwin/pinfo.cc b/winsup/cygwin/pinfo.cc
index 038937e..d0b4cd9 100644
--- a/winsup/cygwin/pinfo.cc
+++ b/winsup/cygwin/pinfo.cc
@@ -38,7 +38,9 @@ public:
pinfo_basic::pinfo_basic ()
{
pid = dwProcessId = GetCurrentProcessId ();
- GetModuleFileNameW (NULL, progname, sizeof (progname) / sizeof (WCHAR));
+ PWCHAR pend = wcpncpy (progname, global_progname,
+ sizeof (progname) / sizeof (WCHAR) - 1);
+ *pend = L'\0';
/* Default uid/gid are needed very early to initialize shared user info. */
uid = ILLEGAL_UID;
gid = ILLEGAL_GID;
@@ -120,20 +122,18 @@ pinfo::status_exit (DWORD x)
{
case STATUS_DLL_NOT_FOUND:
{
- char posix_prog[NT_MAX_PATH];
path_conv pc;
if (!procinfo)
- pc.check ("/dev/null");
+ pc.check ("/dev/null", PC_NOWARN | PC_POSIX);
else
{
UNICODE_STRING uc;
RtlInitUnicodeString(&uc, procinfo->progname);
- pc.check (&uc, PC_NOWARN);
+ pc.check (&uc, PC_NOWARN | PC_POSIX);
}
- mount_table->conv_to_posix_path (pc.get_win32 (), posix_prog, 1);
small_printf ("%s: error while loading shared libraries: %s: cannot "
"open shared object file: No such file or directory\n",
- posix_prog, find_first_notloaded_dll (pc));
+ pc.get_posix (), find_first_notloaded_dll (pc));
x = 127 << 8;
}
break;
diff --git a/winsup/cygwin/pseudo-reloc.cc b/winsup/cygwin/pseudo-reloc.cc
index bdcde2a..f374d22 100644
--- a/winsup/cygwin/pseudo-reloc.cc
+++ b/winsup/cygwin/pseudo-reloc.cc
@@ -85,20 +85,18 @@ __report_error (const char *msg, ...)
* cygwin ptys.
*/
char buf[128];
- WCHAR module[PATH_MAX];
- char * posix_module = NULL;
+ char *posix_module = NULL;
static const char UNKNOWN_MODULE[] = "<unknown module>: ";
static const char CYGWIN_FAILURE_MSG[] = "Cygwin runtime failure: ";
HANDLE errh = GetStdHandle (STD_ERROR_HANDLE);
- ssize_t modulelen = GetModuleFileNameW (NULL, module, PATH_MAX);
va_list args;
/* FIXME: cleanup further to avoid old use of cygwin_internal */
if (errh == INVALID_HANDLE_VALUE)
cygwin_internal (CW_EXIT_PROCESS, STATUS_ILLEGAL_DLL_PSEUDO_RELOCATION, 1);
- if (modulelen > 0)
- posix_module = (char *) cygwin_create_path (CCP_WIN_W_TO_POSIX, module);
+ posix_module = (char *) cygwin_create_path (CCP_WIN_W_TO_POSIX,
+ global_progname);
va_start (args, msg);
vsnprintf (buf, sizeof (buf), msg, args);
diff --git a/winsup/cygwin/smallprint.cc b/winsup/cygwin/smallprint.cc
index a1e0f70..2a8b1ce 100644
--- a/winsup/cygwin/smallprint.cc
+++ b/winsup/cygwin/smallprint.cc
@@ -284,12 +284,6 @@ gen_decimalLL:
dst = rnarg (dst, 16, 0, len, pad);
#endif
break;
- case 'P':
- if (!GetModuleFileName (NULL, tmp, NT_MAX_PATH))
- s = "cygwin program";
- else
- s = tmp;
- goto fillin;
case '.':
n = strtol (fmt, (char **) &fmt, 10);
if (*fmt++ != 's')
@@ -311,6 +305,9 @@ gen_decimalLL:
else
*dst++ = *s++;
break;
+ case 'P':
+ RtlInitUnicodeString (us = &uw, global_progname);
+ goto wfillin;
case 'W':
w = va_arg (ap, PWCHAR);
RtlInitUnicodeString (us = &uw, w ?: L"(null)");
@@ -613,10 +610,7 @@ gen_decimalLL:
#endif
break;
case L'P':
- if (!GetModuleFileNameW (NULL, tmp, NT_MAX_PATH))
- RtlInitUnicodeString (us = &uw, L"cygwin program");
- else
- RtlInitUnicodeString (us = &uw, tmp);
+ RtlInitUnicodeString (us = &uw, global_progname);
goto fillin;
case L'.':
n = wcstoul (fmt, (wchar_t **) &fmt, 10);
diff --git a/winsup/cygwin/strace.cc b/winsup/cygwin/strace.cc
index 9d1c3c2..434f92d 100644
--- a/winsup/cygwin/strace.cc
+++ b/winsup/cygwin/strace.cc
@@ -21,9 +21,13 @@ details. */
#include "dtable.h"
#include "cygheap.h"
#include "child_info.h"
+#include "sync.h"
-#define PROTECT(x) x[sizeof (x)-1] = 0
-#define CHECK(x) if (x[sizeof (x)-1] != 0) { small_printf ("array bound exceeded %d\n", __LINE__); ExitProcess (1); }
+#define PROTECT(x) {x[NT_MAX_PATH - 1] = '\0';}
+#define CHECK(x) if (x[NT_MAX_PATH - 1] != '\0') \
+ { small_printf ("array bound exceeded %d\n", __LINE__); \
+ ExitProcess (1); \
+ }
class strace NO_COPY strace;
@@ -35,25 +39,25 @@ strace::activate (bool isfork)
if (!_active && being_debugged ())
{
char buf[30];
- __small_sprintf (buf, "cYg%8x %lx %d", _STRACE_INTERFACE_ACTIVATE_ADDR, &_active, isfork);
+ __small_sprintf (buf, "cYg%8x %lx %d",
+ _STRACE_INTERFACE_ACTIVATE_ADDR, &_active, isfork);
OutputDebugString (buf);
if (_active)
{
char pidbuf[80];
- WCHAR progname_buf[NT_MAX_PATH - 512];
- WCHAR *progname;
+ PWCHAR progname;
if (myself)
{
- __small_sprintf (pidbuf, "(pid %d, ppid %d, windows pid %u)", myself->pid,
- myself->ppid ?: 1, GetCurrentProcessId ());
+ __small_sprintf (pidbuf, "(pid %d, ppid %d, windows pid %u)",
+ myself->pid, myself->ppid ?: 1,
+ GetCurrentProcessId ());
progname = myself->progname;
}
else
{
- GetModuleFileNameW (NULL, progname_buf,
- sizeof progname_buf / sizeof (WCHAR));
- __small_sprintf (pidbuf, "(windows pid %u)", GetCurrentProcessId ());
- progname = progname_buf;
+ __small_sprintf (pidbuf, "(windows pid %u)",
+ GetCurrentProcessId ());
+ progname = global_progname;
}
prntf (1, NULL, "**********************************************");
prntf (1, NULL, "Program name: %W %s", progname, pidbuf);
@@ -151,32 +155,32 @@ strace::vsprntf (char *buf, const char *func, const char *infmt, va_list ap)
else
{
PWCHAR pn = NULL;
- WCHAR progname[NT_MAX_PATH];
- if (!cygwin_finished_initializing)
- pn = (myself) ? myself->progname : NULL;
- else if (__progname)
- sys_mbstowcs(pn = progname, NT_MAX_PATH, __progname);
-
- WCHAR empty[1] = {};
- PWCHAR p;
- if (!pn)
- GetModuleFileNameW (NULL, pn = progname, sizeof (progname));
- if (!pn)
- p = empty;
- else if ((p = wcsrchr (pn, L'\\')) != NULL)
- p++;
- else if ((p = wcsrchr (pn, L'/')) != NULL)
- p++;
+ WCHAR progname[NAME_MAX];
+ if (cygwin_finished_initializing && __progname)
+ {
+ char *p = strrchr (__progname, '/');
+ if (p)
+ ++p;
+ else
+ p = __progname;
+ char *pe = strrchr (p, '.');
+ if (!pe || !ascii_strcasematch (pe, ".exe"))
+ pe = strrchr (p, '\0');
+ sys_mbstowcs (pn = progname, NAME_MAX, p, pe - p);
+ }
else
- p = pn;
- if (p != progname)
- wcscpy (progname, p);
- if ((p = wcsrchr (progname, '.')) != NULL
- && !wcscasecmp (p, L".exe"))
- *p = '\000';
- p = progname;
+ {
+ PWCHAR p = wcsrchr (global_progname, L'\\');
+ ++p;
+ PWCHAR pe = wcsrchr (p, '.');
+ if (!pe || wcscasecmp (pe, L".exe"))
+ pe = wcsrchr (p, L'\0');
+ pe = wcpncpy (progname, p, pe - p);
+ *pe = L'\0';
+ pn = progname;
+ }
char tmpbuf[20];
- count = __small_sprintf (buf, fmt, *p ? p : L"?", mypid (tmpbuf),
+ count = __small_sprintf (buf, fmt, pn, mypid (tmpbuf),
execing ? "!" : "");
if (func)
count += getfunc (buf + count, func);
@@ -235,14 +239,22 @@ strace::write_childpid (pid_t pid)
/* Printf function used when tracing system calls.
Warning: DO NOT SET ERRNO HERE! */
+static NO_COPY muto strace_buf_guard;
+static NO_COPY char *buf;
void
strace::vprntf (unsigned category, const char *func, const char *fmt, va_list ap)
{
DWORD err = GetLastError ();
int len;
- char buf[NT_MAX_PATH];
+ strace_buf_guard.init ("smallprint_buf")->acquire ();
+ /* Creating buffer on Windows process heap to drop stack pressure and
+ keeping our .bss small. */
+ if (!buf)
+ buf = (char *) HeapAlloc (GetProcessHeap (), 0, NT_MAX_PATH);
+ if (!buf)
+ return;
PROTECT (buf);
SetLastError (err);
@@ -272,6 +284,7 @@ strace::vprntf (unsigned category, const char *func, const char *fmt, va_list ap
if (active ())
write (category, buf, len);
#endif
+ strace_buf_guard.release ();
SetLastError (err);
}
diff --git a/winsup/cygwin/wow64.cc b/winsup/cygwin/wow64.cc
index 070b9c2..098d6c2 100644
--- a/winsup/cygwin/wow64.cc
+++ b/winsup/cygwin/wow64.cc
@@ -192,19 +192,17 @@ wow64_revert_to_original_stack (PVOID &allocationbase)
void
wow64_respawn_process ()
{
- WCHAR path[PATH_MAX];
PROCESS_INFORMATION pi;
STARTUPINFOW si;
DWORD ret = 0;
- GetModuleFileNameW (NULL, path, PATH_MAX);
GetStartupInfoW (&si);
- if (!CreateProcessW (path, GetCommandLineW (), NULL, NULL, TRUE,
+ if (!CreateProcessW (global_progname, GetCommandLineW (), NULL, NULL, TRUE,
CREATE_DEFAULT_ERROR_MODE
| GetPriorityClass (GetCurrentProcess ()),
NULL, NULL, &si, &pi))
api_fatal ("Failed to create process <%W> <%W>, %E",
- path, GetCommandLineW ());
+ global_progname, GetCommandLineW ());
CloseHandle (pi.hThread);
if (WaitForSingleObject (pi.hProcess, INFINITE) == WAIT_FAILED)
api_fatal ("Waiting for process %u failed, %E", pi.dwProcessId);