Patch Name: PHCO_30618

Patch Description: s700_800 11.04 (VVOS) Pthread library cumulative patch

Creation Date: 04/03/23

Post Date: 04/03/29

Hardware Platforms - OS Releases:
	s700: 11.04
	s800: 11.04

Products: N/A

Filesets:
	OS-Core.C-MIN-32ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP
	OS-Core.C-MIN-64ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP
	OS-Core.CORE-64SLIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP
	OS-Core.CORE-SHLIBS,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP

Automatic Reboot?: No

Status: General Release

Critical:
	Yes
	PHCO_30618: HANG
		Based on HP-UX Patch PHCO_29959:  HANG
	PHCO_29761: ABORT HANG
		Based on HP-UX Patch PHCO_29108:  HANG
		Based on HP-UX Patch PHCO_26960:  ABORT
	PHKL_18945: ABORT
		Based on HP-UX Patch PHKL_17935:  ABORT
		This defect could result in an application core
		dump.
		Based on HP-UX Patch PHKL_17709:  ABORT
		This defect could result in an application hang.

Category Tags:
	defect_repair enhancement general_release critical
	halts_system

Path Name: /hp-ux_patches/s700_800/11.X/PHCO_30618

Symptoms:
	PHCO_30618:
	Ported HP-UX patch PHCO_29959 to VVOS

	Based on HP-UX patch PHCO_29959:
	( SR:8606338187 CR:JAGae99161 )
	Under certain circumstances, a multi-threaded application
	that has a thread suspending itself while depending upon a
	different thread to resume it, could experience a hang.

	PHCO_29761:
	Ported HP-UX patch PHCO_29108 to VVOS

	Based on HP-UX patch PHCO_29108:
	( SR:8606307008 CR:JAGae70043 )
	Java processes can hang occasionally.

	( SR:8606294128 CR:JAGae57868 )
	Thread can get cancelled even though cancellation is
	disabled.

	( SR:8606314230 CR:JAGae77005 )
	The pthread library does not export two functions that are
	useful to the Java virtual machine.

	Based on HP-UX patch PHCO_26960:
	( SR:8606245135 CR:JAGae11610 )
	Application fails with internal error in pthread library
	when the kernel patch that implements a new light weight
	syscall is not applied.

	( SR:8606249251 CR:JAGae15645 )
	Application aborts when a detached thread forks child
	process.

	( SR:8606232793 CR:JAGae02021 )
	Private mutex lock throughput not acceptable for some
	applications with heavy mutex contention.

	( SR:8606255251 CR:JAGae19578 )
	pthread_cancel() fails to cancel a thread in certain
	conditions.

	( SR:8606259437 CR:JAGae23755 )
	pthread_mutex_destroy() intermittently returns EBUSY
	even when there are no threads accessing the mutex.

	Based on HP-UX patch PHCO_23792:
	libpthread didn't support initialized TLS variables.

	PHCO_21164:
	Ported HP-UX patch PHCO_19666 to VVOS

	Based on HP-UX patch PHCO_19666:
	Libc was unable to use thread callbacks, which are needed
	for multithreaded performance enhancements.
	JAGab19980

	PHKL_18945:
	Ported HP-UX patch PHKL_17935 to VVOS

	Based on HP-UX patch PHKL_17935:
	SR: 1653296962  CR: JAGaa94129
	An application that calls pthread_create() can terminate
	with the following error when running on a system with heavy
	memory usage:
	    Pthread internal error:  message: __alloc_stack()

	Based on HP-UX patch PHKL_17709:
	When calling pthread_[cond,mutex,rwlock]_init(), subsequent
	use of these objects can cause the process or thread to hang
	if the error is not properly checked, or structures
	associated with these routines are not properly initialized.

	Based on HP-UX patch PHKL_17294:
	If you have installed Patch PHKL_17390 and you use java and
	the pthread asynchronous cancellation feature you may
	experience incorrect program behavior -- possible program
	aborts, hangs, etc.

	If you do not use the pthreads asynchronous cancellation
	feature, this patch is not required.

	Based on HP-UX patch PHKL_16239:
	SCHED_TIMESHARE thread priorities degrade over time and with
	cpu usage.  SCHED_NOAGE provides a scheduling policy where
	the priority does not degrade.

	In order to utilize the SCHED_NOAGE feature, patch
	PHKL_16236 must be installed along with PHKL_16239.  The
	order of installation is not important.  If this feature
	will not be used, PHKL_16236 is not necessary.

	Based on HP-UX patch PHKL_16368:
	System peformance degrades when thread spinlock contention
	occurs.

	libpthread enhancement to improve thread spinlock
	performance and overall system performance by lowering the
	amount of bus traffic during spinlock contention.

Defect Description:
	PHCO_30618:
	Ported HP-UX patch PHCO_29959 to VVOS

	Based on HP-UX patch PHCO_29959:
	( SR:8606338187 CR:JAGae99161 )
	Pthread library keeps track of thread suspensions using
	internal suspend count, Suspend count is incremented when
	a thread gets suspended and decremented when thread is
	resumed. The problem occurs when a thread suspends itself
	inside a loop while waiting for a different thread to
	resume it. The thread suspending itself may never get
	resumed since the suspend count maintained inside the
	library will not match the actual suspension state of
	the thread.

	Resolution:
	The internal counter that maintains thread's suspend
	count has been fixed to avoid this situation.

	PHCO_29761:
	Ported HP-UX patch PHCO_29108 to VVOS

	Based on HP-UX patch PHCO_29108:
	( SR:8606307008 CR:JAGae70043 )
	During normal operation, the Java Virtual Machine may
	suspend a thread.  When a thread gets suspended, it
	could be holding internal pthread resources. This can
	cause a deadlock.

	Resolution:
	Solution is to ensure target does not get suspended while
	holding internal pthread resources.

	( SR:8606294128 CR:JAGae57868 )
	The cancellation operation (pthread_cancel) can race with
	cancel enable/disable (pthread_setcancelstate).

	Resolution:
	While cancelling a thread, detect that the thread has now
	disabled cancellation.

	( SR:8606314230 CR:JAGae77005 )
	The pthread library does not export two functions that are
	useful to the Java virtual machine.

	Resolution:
	libpthread will now export the two symbols

	Based on HP-UX patch PHCO_26960:
	( SR:8606245135 CR:JAGae11610 )
	If SIGSYS is ignored by the application, the sigtimedwait()
	system call finds no pending SIGSYS after the check for
	new light weight system call fails with ENOSYS. This
	results in pthread internal error because SIGSYS was
	expected.

	Resolution:
	The check for new syscall is aptly handled so that
	internal error doesn't occur.

	( SR:8606249251 CR:JAGae15645 )
	In the child process forked from a detached thread, the
	first thread in the exit path references a stale pointer.
	This results in application aborting in pthread library.

	Resolution:
	The stale pointer is reset in the child fork cleanup path.

	( SR:8606232793 CR:JAGae02021 )
	When large number of threads contend for a mutex, it
	results in contention for the internal lock of the
	mutex, thereby exacerbating the mutex contention seen by
	the application.

	Resolution:
	The pthread mutex unlock path has been modified to release
	internal lock before waking up a waiting thread, and thus
	reducing contention for the internal lock and improving
	performance.

	The performance changes can take effect only if the POSIX
	real-time restrictions on threads waiting on a mutex are
	relaxed. This is done by disabling the mutex handoff
	mode for real-time  threads and can be done using
	pthread_mutex_disable_handoff_np() or
	pthread_mutexattr_disable_handoff_np() or by setting the
	environment variable   PTHREAD_DISABLE_HANDOFF=ON. By
	default these performance changes are disabled.

	The first API pthread_mutex_disable_handoff_np() is for
	process  wide disabling  of handoff mode in all mutexes.
	So is the environment variable PTHREAD_DISABLE_HANDOFF.
	The pthread_mutexattr_disable_handoff_np() takes an
	argument pointer to pthread_mutexattr_t and can be used
	to  disable  handoff  mode  for a particular  mutex.
	The pthread_mutex_disable_handoff_np() has no arguments
	and has to be called by the main thread before any new
	threads are created.

	"Handoff mode" is used to strictly adhere to POSIX
	real-time characteristics, when real-time threads
	waiting on a mutex are woken up. If the application
	does not have any real-time  threads  acquiring mutex
	locks, or if the application does not rely on strict
	real-time  behavior of real-time  threads  waiting on
	a mutex, the mutex handoff mode can be disabled, to
	take advantage of these performance changes.

	( SR:8606255251 CR:JAGae19578 )
	There is a race condition in thread cancellation path in
	pthread library, because of which pthread_cancel() fails
	to cancel a thread.

	Resolution:
	The race condition in the cancellation path is removed
	by protecting the internal cancellation structure with
	a spinlock.

	( SR:8606259437 CR:JAGae23755 )
	The problem with pthread_mutex_destroy() is attributed
	to the fact that, pthread_mutex_unlock() does not keep
	track of the number of waiters accurately. The mutex
	cannot be destroyed when there are waiters, and hence
	EBUSY is returned by pthread_mutex_destroy().

	Resolution:
	The change introduced in this patch will accurately
	keep track of all the waiters.

	Based on HP-UX patch PHCO_23792:
	Initialized TLS variable support.

	PHCO_21164:
	Ported HP-UX patch PHCO_19666 to VVOS

	Based on HP-UX patch PHCO_19666:
	Multithreaded performance enhancement
	JAGab19980

	PHKL_18945:
	Ported HP-UX patch PHKL_17935 to VVOS

	Based on HP-UX patch PHKL_17935:
	SR: 1653296962  CR: JAGaa94129
	The pthread_create() path uses mmap() to allocate a stack.
	pthread_create() checks for a NULL return.  However, mmap()
	returns MAP_FAILED if it cannot perform the allocation.
	Typically what happens is that the subsequent mprotect()
	will fail to setup the guard page, then munmap() fails when
	trying to clean up on the error return path, generating an
	"INTERNAL ERROR" message and a core dump from the library.

	Also, since the mmap() failure check passes even if it fails
	(we're not looking for the correct return value),
	pthread_create() doesn't return an error.  Instead, it
	terminates with "INTERNAL ERROR."

	Resolution:
	pthread_create() now checks for MAP_FAILED and returns the
	error instead of failing with "INTERNAL ERROR.".

	Based on HP-UX patch PHKL_17709:
	Structures associated with
	pthread_[cond,mutex,rwlock]_init() are not being initialized
	correctly.  This causes a call to these routines to return
	EBUSY.

	Resolution:
	We no longer check for "cookie" values to validate these
	objects.  We unconditionally initialize them.

	Based on HP-UX patch PHKL_17294:
	A kernel interface change required that we save a register
	in a new location when the application enters the kernel via
	the trap path.  The kernel change was made in patch
	PHKL_17390.

	Resolution:  The pthreads library must now look in the new
	location for the register value in this case.

	Based on HP-UX patch PHKL_16239:
	The SCHED_NOAGE scheduling policy has approximately the same
	priority range as SCHED_TIMESHARE.  However, the priority
	does not degrade with time or cpu usage.  It provides an
	alternative to real time processes which always run first
	and have the possibility of taking over the system.

	Based on HP-UX patch PHKL_16368:
	The thread library spinlock did not take advantage of the
	cached lock value.  In addition, it performed an unnecessary
	fetch each time through the 'spin' loop while waiting for
	the lock to be free.  These conditions caused a large amount
	of unnecessary bus traffic.

Enhancement:
	No (superseded patches contained enhancements)
	PHCO_21164:
	Ported HP-UX patch PHCO_19666 to VVOS

	Based on HP-UX patch PHCO_19666:
	Libc was unable to use thread callbacks, which are needed
	for multithreaded performance enhancements.

	PHKL_18945:
	Ported HP-UX patch PHKL_17935 to VVOS

	Based on HP-UX patch PHKL_17935:
	libpthread enhancement to improve thread spinlock
	performance and overall system performance by lowering the
	amount of bus traffic during spinlock contention.

SR:
	1653294868 1653296962 4701401240 5003360446 5003451591
	8606184540 8606232793 8606245135 8606249251 8606338187
	8606255251 8606259437 8606294128 8606307008 8606314230
	4701398123 8606186056 8606353311

Patch Files:
	
	OS-Core.C-MIN-32ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/libpthread.a
	/usr/lib/libpthread_tr.a

	OS-Core.C-MIN-64ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/pa20_64/libpthread.a
	/usr/lib/pa20_64/libpthread_tr.a

	OS-Core.CORE-64SLIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/pa20_64/libpthread.1
	/usr/lib/pa20_64/libpthread_tr.1

	OS-Core.CORE-SHLIBS,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/libpthread.1
	/usr/lib/libpthread_tr.1

what(1) Output:
	
	OS-Core.C-MIN-32ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/libpthread.a:
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 18:04
			:40 EST 2004
	/usr/lib/libpthread_tr.a:
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 18:07
			:11 EST 2004

	OS-Core.C-MIN-64ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/pa20_64/libpthread.a:
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 19:20
			:55 EST 2004
	/usr/lib/pa20_64/libpthread_tr.a:
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 19:23
			:36 EST 2004

	OS-Core.CORE-64SLIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/pa20_64/libpthread.1:
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 19:22
			:17 EST 2004
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)
	/usr/lib/pa20_64/libpthread_tr.1:
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 19:24
			:57 EST 2004
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)

	OS-Core.CORE-SHLIBS,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	/usr/lib/libpthread.1:
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 18:05
			:56 EST 2004
	/usr/lib/libpthread_tr.1:
		libpthread.c $Date: 2003/12/05 21:50:14 $Revision: r
			11ros/11 PATCH_11.00 (PHCO_29959)
		Pthread Interfaces
		libpthread HP-UX (Release B.11.04): Thu Mar 18 18:08
			:29 EST 2004

cksum(1) Output:
	
	OS-Core.C-MIN-32ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	463741115 227674 /usr/lib/libpthread.a
	3699842692 257394 /usr/lib/libpthread_tr.a

	OS-Core.C-MIN-64ALIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	316068096 379046 /usr/lib/pa20_64/libpthread.a
	4225565985 432252 /usr/lib/pa20_64/libpthread_tr.a

	OS-Core.CORE-64SLIB,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	4285880284 135800 /usr/lib/pa20_64/libpthread.1
	2077418089 165104 /usr/lib/pa20_64/libpthread_tr.1

	OS-Core.CORE-SHLIBS,fr=B.11.04,fa=HP-UX_B.11.04_32/64,v=HP:
	630051278 143360 /usr/lib/libpthread.1
	1519245272 167936 /usr/lib/libpthread_tr.1

Patch Conflicts: None

Patch Dependencies:
	s700: 11.04: PHKL_19142
	s800: 11.04: PHKL_19142

Hardware Dependencies: None

Other Dependencies: None

Supersedes:
	PHKL_18945 PHCO_21164 PHCO_29761

Equivalent Patches:
	PHCO_29959:
	s700: 11.00
	s800: 11.00

	PHCO_29960:
	s700: 11.11
	s800: 11.11

Patch Package Size: 530 KBytes

Installation Instructions:
	Please review all instructions and the Hewlett-Packard
	SupportLine User Guide or your Hewlett-Packard support terms
	and conditions for precautions, scope of license,
	restrictions, and, limitation of liability and warranties,
	before installing this patch.
	------------------------------------------------------------
	1. Back up your system before installing a patch.

	2. Login as root.

	3. Copy the patch to the /tmp directory.

	4. Move to the /tmp directory and unshar the patch:

		cd /tmp
		sh PHCO_30618

	5. Run swinstall to install the patch:

		swinstall -x autoreboot=true -x patch_match_target=true \
			  -s /tmp/PHCO_30618.depot

	By default swinstall will archive the original software in 
	/var/adm/sw/save/PHCO_30618.  If you do not wish to retain a
	copy of the original software, include the patch_save_files
	option in the swinstall command above:

		-x patch_save_files=false

	WARNING: If patch_save_files is false when a patch is installed,
		 the patch cannot be deinstalled.  Please be careful
		 when using this feature.

	For future reference, the contents of the PHCO_30618.text file is 
	available in the product readme:

		swlist -l product -a readme -d @ /tmp/PHCO_30618.depot

	To put this patch on a magnetic tape and install from the
	tape drive, use the command:

		dd if=/tmp/PHCO_30618.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions: None