This patch remove the PID cache and usage in current GLIBC code. Current
usage is mainly used a performance optimization to avoid the syscall,
however it adds some issues:
- The exposed clone syscall will try to set pid/tid to make the new
thread somewhat compatible with current GLIBC assumptions. This cause
a set of issue with new workloads and usecases (such as BZ#17214 and
[1]) as well for new internal usage of clone to optimize other algorithms
(such as clone plus CLONE_VM for posix_spawn, BZ#19957).
- The caching complexity also added some bugs in the past [2] [3] and
requires more effort of each port to handle such requirements (for
both clone and vfork implementation).
- Caching performance gain in mainly on getpid and some specific
code paths. The getpid performance leverage is questionable [4],
either by the idea of getpid being a hotspot as for the getpid
implementation itself (if it is indeed a justifiable hotspot a
vDSO symbol could let to a much more simpler solution).
Other usage is mainly for non usual code paths, such as pthread
cancellation signal and handling.
For thread creation (on stack allocation) the code simplification in fact
adds some performance gain due the no need of transverse the stack cache
and invalidate each element pid.
Other thread usages will require a direct getpid syscall, such as
cancellation/setxid signal, thread cancellation, thread fail path (at
create_thread), and thread signal (pthread_kill and pthread_sigqueue).
However these are hardly usual hotspots and I think adding a syscall is
justifiable.
It also simplifies both the clone and vfork arch-specific implementation.
And by review each fork implementation there are some discrepancies that
this patch also solves:
- microblaze clone/vfork does not set/reset the pid/tid field
- hppa uses the default vfork implementation that fallback to fork.
Since vfork is deprecated I do not think we should bother with it.
The patch also removes the TID caching in clone. My understanding for
such semantic is try provide some pthread usage after a user program
issue clone directly (as done by thread creation with CLONE_PARENT_SETTID
and pthread tid member). However, as stated before in multiple discussions
threads, GLIBC provides clone syscalls without further supporting all this
semantics.
I ran a full make check on x86_64, x32, i686, armhf, aarch64, and powerpc64le.
For sparc32, sparc64, and mips I ran the basic fork and vfork tests from
posix/ folder (on a qemu system). So it would require further testing
on alpha, hppa, ia64, m68k, nios2, s390, sh, and tile (I excluded microblaze
because it is already implementing the patch semantic regarding clone/vfork).
[1] https://codereview.chromium.org/
800183004/
[2] https://sourceware.org/ml/libc-alpha/2006-07/msg00123.html
[3] https://sourceware.org/bugzilla/show_bug.cgi?id=15368
[4] http://yarchive.net/comp/linux/getpid_caching.html
* sysdeps/nptl/fork.c (__libc_fork): Remove pid cache setting.
* nptl/allocatestack.c (allocate_stack): Likewise.
(__reclaim_stacks): Likewise.
(setxid_signal_thread): Obtain pid through syscall.
* nptl/nptl-init.c (sigcancel_handler): Likewise.
(sighandle_setxid): Likewise.
* nptl/pthread_cancel.c (pthread_cancel): Likewise.
* sysdeps/unix/sysv/linux/pthread_kill.c (__pthread_kill): Likewise.
* sysdeps/unix/sysv/linux/pthread_sigqueue.c (pthread_sigqueue):
Likewise.
* sysdeps/unix/sysv/linux/createthread.c (create_thread): Likewise.
* sysdeps/unix/sysv/linux/getpid.c: Remove file.
* nptl/descr.h (struct pthread): Change comment about pid value.
* nptl/pthread_getattr_np.c (pthread_getattr_np): Remove thread
pid assert.
* sysdeps/unix/sysv/linux/pthread-pids.h (__pthread_initialize_pids):
Do not set pid value.
* nptl_db/td_ta_thr_iter.c (iterate_thread_list): Remove thread
pid cache check.
* nptl_db/td_thr_validate.c (td_thr_validate): Likewise.
* sysdeps/aarch64/nptl/tcb-offsets.sym: Remove pid offset.
* sysdeps/alpha/nptl/tcb-offsets.sym: Likewise.
* sysdeps/arm/nptl/tcb-offsets.sym: Likewise.
* sysdeps/hppa/nptl/tcb-offsets.sym: Likewise.
* sysdeps/i386/nptl/tcb-offsets.sym: Likewise.
* sysdeps/ia64/nptl/tcb-offsets.sym: Likewise.
* sysdeps/m68k/nptl/tcb-offsets.sym: Likewise.
* sysdeps/microblaze/nptl/tcb-offsets.sym: Likewise.
* sysdeps/mips/nptl/tcb-offsets.sym: Likewise.
* sysdeps/nios2/nptl/tcb-offsets.sym: Likewise.
* sysdeps/powerpc/nptl/tcb-offsets.sym: Likewise.
* sysdeps/s390/nptl/tcb-offsets.sym: Likewise.
* sysdeps/sh/nptl/tcb-offsets.sym: Likewise.
* sysdeps/sparc/nptl/tcb-offsets.sym: Likewise.
* sysdeps/tile/nptl/tcb-offsets.sym: Likewise.
* sysdeps/x86_64/nptl/tcb-offsets.sym: Likewise.
* sysdeps/unix/sysv/linux/aarch64/clone.S: Remove pid and tid caching.
* sysdeps/unix/sysv/linux/alpha/clone.S: Likewise.
* sysdeps/unix/sysv/linux/arm/clone.S: Likewise.
* sysdeps/unix/sysv/linux/hppa/clone.S: Likewise.
* sysdeps/unix/sysv/linux/i386/clone.S: Likewise.
* sysdeps/unix/sysv/linux/ia64/clone2.S: Likewise.
* sysdeps/unix/sysv/linux/mips/clone.S: Likewise.
* sysdeps/unix/sysv/linux/nios2/clone.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/clone.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/sh/clone.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/clone.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/tile/clone.S: Likewise.
* sysdeps/unix/sysv/linux/x86_64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/aarch64/vfork.S: Remove pid set and reset.
* sysdeps/unix/sysv/linux/alpha/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/arm/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/i386/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/ia64/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/m68k/clone.S: Likewise.
* sysdeps/unix/sysv/linux/m68k/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/mips/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/nios2/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/sh/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/tile/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/x86_64/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/tst-clone2.c (f): Remove direct pthread
struct access.
(clone_test): Remove function.
(do_test): Rewrite to take in consideration pid is not cached anymore.
(cherry picked from commit
c579f48edba88380635ab98cb612030e3ed8691e)
+2016-11-24 Adhemerval Zanella <adhemerval.zanella@linaro.org>
+
+ * sysdeps/nptl/fork.c (__libc_fork): Remove pid cache setting.
+ * nptl/allocatestack.c (allocate_stack): Likewise.
+ (__reclaim_stacks): Likewise.
+ (setxid_signal_thread): Obtain pid through syscall.
+ * nptl/nptl-init.c (sigcancel_handler): Likewise.
+ (sighandle_setxid): Likewise.
+ * nptl/pthread_cancel.c (pthread_cancel): Likewise.
+ * sysdeps/unix/sysv/linux/pthread_kill.c (__pthread_kill): Likewise.
+ * sysdeps/unix/sysv/linux/pthread_sigqueue.c (pthread_sigqueue):
+ Likewise.
+ * sysdeps/unix/sysv/linux/createthread.c (create_thread): Likewise.
+ * sysdeps/unix/sysv/linux/raise.c (raise): Remove old behaviour
+ comment.
+ * sysdeps/unix/sysv/linux/getpid.c: Remove file.
+ * nptl/descr.h (struct pthread): Change comment about pid value.
+ * nptl/pthread_getattr_np.c (pthread_getattr_np): Remove thread
+ pid assert.
+ * sysdeps/unix/sysv/linux/pthread-pids.h (__pthread_initialize_pids):
+ Do not set pid value.
+ * nptl_db/td_ta_thr_iter.c (iterate_thread_list): Remove thread
+ pid cache check.
+ * nptl_db/td_thr_validate.c (td_thr_validate): Likewise.
+ * sysdeps/aarch64/nptl/tcb-offsets.sym: Remove pid offset.
+ * sysdeps/alpha/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/arm/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/hppa/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/i386/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/ia64/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/m68k/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/microblaze/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/mips/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/nios2/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/powerpc/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/s390/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/sh/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/sparc/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/tile/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/x86_64/nptl/tcb-offsets.sym: Likewise.
+ * sysdeps/unix/sysv/linux/aarch64/clone.S: Remove pid and tid caching.
+ * sysdeps/unix/sysv/linux/alpha/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/arm/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/hppa/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/i386/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/ia64/clone2.S: Likewise.
+ * sysdeps/unix/sysv/linux/mips/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/nios2/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/s390/s390-32/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/s390/s390-64/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/sh/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/sparc/sparc32/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/sparc/sparc64/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/tile/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/x86_64/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/aarch64/vfork.S: Remove pid set and reset.
+ * sysdeps/unix/sysv/linux/alpha/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/arm/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/i386/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/ia64/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/m68k/clone.S: Likewise.
+ * sysdeps/unix/sysv/linux/m68k/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/mips/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/nios2/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/powerpc/powerpc32/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/s390/s390-32/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/s390/s390-64/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/sh/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/sparc/sparc32/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/sparc/sparc64/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/tile/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/x86_64/vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/hppa/pt-vfork.S: Likewise.
+ * sysdeps/unix/sysv/linux/tst-clone2.c (f): Remove direct pthread
+ struct access.
+ (clone_test): Remove function.
+ (do_test): Rewrite to take in consideration pid is not cached anymore.
+
2016-09-26 Adhemerval Zanella <adhemerval.zanella@linaro.org>
* sysdeps/unix/sysdep.h (__INTERNAL_SYSCALL0): New macro.
SETUP_THREAD_SYSINFO (pd);
#endif
- /* The process ID is also the same as that of the caller. */
- pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
-
/* Don't allow setxid until cloned. */
pd->setxid_futex = -1;
/* Don't allow setxid until cloned. */
pd->setxid_futex = -1;
- /* The process ID is also the same as that of the caller. */
- pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
-
/* Allocate the DTV for this thread. */
if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL)
{
/* This marks the stack as free. */
curp->tid = 0;
- /* The PID field must be initialized for the new process. */
- curp->pid = self->pid;
-
/* Account for the size of the stack. */
stack_cache_actsize += curp->stackblock_size;
}
}
- /* Reset the PIDs in any cached stacks. */
- list_for_each (runp, &stack_cache)
- {
- struct pthread *curp = list_entry (runp, struct pthread, list);
- curp->pid = self->pid;
- }
-
/* Add the stack of all running threads to the cache. */
list_splice (&stack_used, &stack_cache);
return 0;
int val;
+ pid_t pid = __getpid ();
INTERNAL_SYSCALL_DECL (err);
- val = INTERNAL_SYSCALL (tgkill, err, 3, THREAD_GETMEM (THREAD_SELF, pid),
- t->tid, SIGSETXID);
+ val = INTERNAL_SYSCALL_CALL (tgkill, err, pid, t->tid, SIGSETXID);
/* If this failed, it must have had not started yet or else exited. */
if (!INTERNAL_SYSCALL_ERROR_P (val, err))
therefore stack) used' flag. */
pid_t tid;
- /* Process ID - thread group ID in kernel speak. */
- pid_t pid;
+ /* Ununsed. */
+ pid_t pid_ununsed;
/* List of robust mutexes the thread is holding. */
#ifdef __PTHREAD_MUTEX_HAVE_PREV
static void
sigcancel_handler (int sig, siginfo_t *si, void *ctx)
{
- /* Determine the process ID. It might be negative if the thread is
- in the middle of a fork() call. */
- pid_t pid = THREAD_GETMEM (THREAD_SELF, pid);
- if (__glibc_unlikely (pid < 0))
- pid = -pid;
-
/* Safety check. It would be possible to call this function for
other signals and send a signal from another process. This is not
correct and might even be a security problem. Try to catch as
many incorrect invocations as possible. */
if (sig != SIGCANCEL
- || si->si_pid != pid
+ || si->si_pid != __getpid()
|| si->si_code != SI_TKILL)
return;
static void
sighandler_setxid (int sig, siginfo_t *si, void *ctx)
{
- /* Determine the process ID. It might be negative if the thread is
- in the middle of a fork() call. */
- pid_t pid = THREAD_GETMEM (THREAD_SELF, pid);
int result;
- if (__glibc_unlikely (pid < 0))
- pid = -pid;
/* Safety check. It would be possible to call this function for
other signals and send a signal from another process. This is not
correct and might even be a security problem. Try to catch as
many incorrect invocations as possible. */
if (sig != SIGSETXID
- || si->si_pid != pid
+ || si->si_pid != __getpid ()
|| si->si_code != SI_TKILL)
return;
#include "pthreadP.h"
#include <atomic.h>
#include <sysdep.h>
-
+#include <unistd.h>
int
pthread_cancel (pthread_t th)
#ifdef SIGCANCEL
/* The cancellation handler will take care of marking the
thread as canceled. */
- INTERNAL_SYSCALL_DECL (err);
-
- /* One comment: The PID field in the TCB can temporarily be
- changed (in fork). But this must not affect this code
- here. Since this function would have to be called while
- the thread is executing fork, it would have to happen in
- a signal handler. But this is no allowed, pthread_cancel
- is not guaranteed to be async-safe. */
- int val;
- val = INTERNAL_SYSCALL (tgkill, err, 3,
- THREAD_GETMEM (THREAD_SELF, pid), pd->tid,
- SIGCANCEL);
+ pid_t pid = getpid ();
+ INTERNAL_SYSCALL_DECL (err);
+ int val = INTERNAL_SYSCALL_CALL (tgkill, err, pid, pd->tid,
+ SIGCANCEL);
if (INTERNAL_SYSCALL_ERROR_P (val, err))
result = INTERNAL_SYSCALL_ERRNO (val, err);
#else
{
/* No stack information available. This must be for the initial
thread. Get the info in some magical way. */
- assert (abs (thread->pid) == thread->tid);
/* Stack size limit. */
struct rlimit rl;
DB_STRUCT_FIELD (pthread, list)
DB_STRUCT_FIELD (pthread, report_events)
DB_STRUCT_FIELD (pthread, tid)
-DB_STRUCT_FIELD (pthread, pid)
DB_STRUCT_FIELD (pthread, start_routine)
DB_STRUCT_FIELD (pthread, cancelhandling)
DB_STRUCT_FIELD (pthread, schedpolicy)
if (ps_pdread (ta->ph, addr, copy, ta->ta_sizeof_pthread) != PS_OK)
return TD_ERR;
- /* Verify that this thread's pid field matches the child PID.
- If its pid field is negative, it's about to do a fork or it
- is the sole thread in a fork child. */
- psaddr_t pid;
- err = DB_GET_FIELD_LOCAL (pid, ta, copy, pthread, pid, 0);
- if (err == TD_OK && (pid_t) (uintptr_t) pid < 0)
- {
- if (-(pid_t) (uintptr_t) pid == match_pid)
- /* It is about to do a fork, but is really still the parent PID. */
- pid = (psaddr_t) (uintptr_t) match_pid;
- else
- /* It must be a fork child, whose new PID is in the tid field. */
- err = DB_GET_FIELD_LOCAL (pid, ta, copy, pthread, tid, 0);
- }
+ err = DB_GET_FIELD_LOCAL (schedpolicy, ta, copy, pthread,
+ schedpolicy, 0);
if (err != TD_OK)
break;
+ err = DB_GET_FIELD_LOCAL (schedprio, ta, copy, pthread,
+ schedparam_sched_priority, 0);
+ if (err != TD_OK)
+ break;
+
+ /* Now test whether this thread matches the specified conditions. */
- if ((pid_t) (uintptr_t) pid == match_pid)
+ /* Only if the priority level is as high or higher. */
+ int descr_pri = ((uintptr_t) schedpolicy == SCHED_OTHER
+ ? 0 : (uintptr_t) schedprio);
+ if (descr_pri >= ti_pri)
{
- err = DB_GET_FIELD_LOCAL (schedpolicy, ta, copy, pthread,
- schedpolicy, 0);
- if (err != TD_OK)
- break;
- err = DB_GET_FIELD_LOCAL (schedprio, ta, copy, pthread,
- schedparam_sched_priority, 0);
- if (err != TD_OK)
- break;
-
- /* Now test whether this thread matches the specified conditions. */
-
- /* Only if the priority level is as high or higher. */
- int descr_pri = ((uintptr_t) schedpolicy == SCHED_OTHER
- ? 0 : (uintptr_t) schedprio);
- if (descr_pri >= ti_pri)
- {
- /* Yep, it matches. Call the callback function. */
- td_thrhandle_t th;
- th.th_ta_p = (td_thragent_t *) ta;
- th.th_unique = addr;
- if (callback (&th, cbdata_p) != 0)
- return TD_DBERR;
- }
+ /* Yep, it matches. Call the callback function. */
+ td_thrhandle_t th;
+ th.th_ta_p = (td_thragent_t *) ta;
+ th.th_unique = addr;
+ if (callback (&th, cbdata_p) != 0)
+ return TD_DBERR;
}
/* Get the pointer to the next element. */
err = TD_OK;
}
- if (err == TD_OK)
- {
- /* Verify that this is not a stale element in a fork child. */
- pid_t match_pid = ps_getpid (th->th_ta_p->ph);
- psaddr_t pid;
- err = DB_GET_FIELD (pid, th->th_ta_p, th->th_unique, pthread, pid, 0);
- if (err == TD_OK && (pid_t) (uintptr_t) pid < 0)
- {
- /* This was a thread that was about to fork, or it is the new sole
- thread in a fork child. In the latter case, its tid was stored
- via CLONE_CHILD_SETTID and so is already the proper child PID. */
- if (-(pid_t) (uintptr_t) pid == match_pid)
- /* It is about to do a fork, but is really still the parent PID. */
- pid = (psaddr_t) (uintptr_t) match_pid;
- else
- /* It must be a fork child, whose new PID is in the tid field. */
- err = DB_GET_FIELD (pid, th->th_ta_p, th->th_unique,
- pthread, tid, 0);
- }
- if (err == TD_OK && (pid_t) (uintptr_t) pid != match_pid)
- err = TD_NOTHR;
- }
-
return err;
}
#include <tls.h>
PTHREAD_MULTIPLE_THREADS_OFFSET offsetof (struct pthread, header.multiple_threads)
-PTHREAD_PID_OFFSET offsetof (struct pthread, pid)
PTHREAD_TID_OFFSET offsetof (struct pthread, tid)
PTHREAD_SIZEOF sizeof (struct pthread)
#define thread_offsetof(mem) (long)(offsetof(struct pthread, mem) - sizeof(struct pthread))
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
-PID_OFFSET thread_offsetof (pid)
TID_OFFSET thread_offsetof (tid)
#define thread_offsetof(mem) (long)(offsetof(struct pthread, mem) - sizeof(struct pthread))
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
-PID_OFFSET thread_offsetof (pid)
TID_OFFSET thread_offsetof (tid)
RESULT offsetof (struct pthread, result)
TID offsetof (struct pthread, tid)
-PID offsetof (struct pthread, pid)
CANCELHANDLING offsetof (struct pthread, cancelhandling)
CLEANUP_JMP_BUF offsetof (struct pthread, cleanup_jmp_buf)
MULTIPLE_THREADS_OFFSET offsetof (struct pthread, header.multiple_threads)
-- This way we get the offset of a member in the struct pthread that
-- preceeds the thread pointer (which points to the dtv).
#define thread_offsetof(mem) (unsigned int)(offsetof(struct pthread, mem) - sizeof(struct pthread))
-PID_THREAD_OFFSET thread_offsetof (pid)
TID_THREAD_OFFSET thread_offsetof (tid)
MULTIPLE_THREADS_THREAD_OFFSET thread_offsetof (header.multiple_threads)
RESULT offsetof (struct pthread, result)
TID offsetof (struct pthread, tid)
-PID offsetof (struct pthread, pid)
CANCELHANDLING offsetof (struct pthread, cancelhandling)
CLEANUP_JMP_BUF offsetof (struct pthread, cleanup_jmp_buf)
MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads)
#include <sysdep.h>
#include <tls.h>
-PID offsetof (struct pthread, pid) - TLS_PRE_TCB_SIZE
TID offsetof (struct pthread, tid) - TLS_PRE_TCB_SIZE
MULTIPLE_THREADS_OFFSET offsetof (struct pthread, header.multiple_threads) - TLS_PRE_TCB_SIZE
SYSINFO_OFFSET offsetof (tcbhead_t, __private)
#define thread_offsetof(mem) (long)(offsetof(struct pthread, mem) - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
-PID_OFFSET thread_offsetof (pid)
TID_OFFSET thread_offsetof (tid)
#define thread_offsetof(mem) (long)(offsetof (struct pthread, mem) - sizeof (struct pthread))
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
-PID_OFFSET thread_offsetof (pid)
TID_OFFSET thread_offsetof (tid)
#define thread_offsetof(mem) (long)(offsetof(struct pthread, mem) - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
-PID_OFFSET thread_offsetof (pid)
TID_OFFSET thread_offsetof (tid)
# define thread_offsetof(mem) ((ptrdiff_t) THREAD_SELF + offsetof (struct pthread, mem))
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
-PID_OFFSET thread_offsetof (pid)
TID_OFFSET thread_offsetof (tid)
POINTER_GUARD (offsetof (tcbhead_t, pointer_guard) - TLS_TCB_OFFSET - sizeof (tcbhead_t))
pid_t ppid = THREAD_GETMEM (THREAD_SELF, tid);
#endif
- /* We need to prevent the getpid() code to update the PID field so
- that, if a signal arrives in the child very early and the signal
- handler uses getpid(), the value returned is correct. */
- pid_t parentpid = THREAD_GETMEM (THREAD_SELF, pid);
- THREAD_SETMEM (THREAD_SELF, pid, -parentpid);
-
#ifdef ARCH_FORK
pid = ARCH_FORK ();
#else
if (__fork_generation_pointer != NULL)
*__fork_generation_pointer += __PTHREAD_ONCE_FORK_GEN_INCR;
- /* Adjust the PID field for the new process. */
- THREAD_SETMEM (self, pid, THREAD_GETMEM (self, tid));
-
#if HP_TIMING_AVAIL
/* The CPU clock of the thread and process have to be set to zero. */
hp_timing_t now;
{
assert (THREAD_GETMEM (THREAD_SELF, tid) == ppid);
- /* Restore the PID value. */
- THREAD_SETMEM (THREAD_SELF, pid, parentpid);
-
/* Release acquired locks in the multi-threaded case. */
if (multiple_threads)
{
#if TLS_MULTIPLE_THREADS_IN_TCB
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
#endif
-PID thread_offsetof (pid)
TID thread_offsetof (tid)
POINTER_GUARD (offsetof (tcbhead_t, pointer_guard) - TLS_TCB_OFFSET - sizeof (tcbhead_t))
TAR_SAVE (offsetof (tcbhead_t, tar_save) - TLS_TCB_OFFSET - sizeof (tcbhead_t))
MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads)
STACK_GUARD offsetof (tcbhead_t, stack_guard)
-PID offsetof (struct pthread, pid)
TID offsetof (struct pthread, tid)
RESULT offsetof (struct pthread, result)
TID offsetof (struct pthread, tid)
-PID offsetof (struct pthread, pid)
CANCELHANDLING offsetof (struct pthread, cancelhandling)
CLEANUP_JMP_BUF offsetof (struct pthread, cleanup_jmp_buf)
MULTIPLE_THREADS_OFFSET offsetof (struct pthread, header.multiple_threads)
MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads)
POINTER_GUARD offsetof (tcbhead_t, pointer_guard)
-PID offsetof (struct pthread, pid)
TID offsetof (struct pthread, tid)
#define thread_offsetof(mem) (long)(offsetof(struct pthread, mem) - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
-PID_OFFSET thread_offsetof (pid)
TID_OFFSET thread_offsetof (tid)
POINTER_GUARD (offsetof (tcbhead_t, pointer_guard) - TLS_TCB_OFFSET - sizeof (tcbhead_t))
FEEDBACK_DATA_OFFSET (offsetof (tcbhead_t, feedback_data) - TLS_TCB_OFFSET - sizeof (tcbhead_t))
cfi_undefined (x30)
mov x29, 0
- tbnz x11, #CLONE_VM_BIT, 1f
-
- mov x8, #SYS_ify(getpid)
- svc 0x0
- mrs x1, tpidr_el0
- sub x1, x1, #PTHREAD_SIZEOF
- str w0, [x1, #PTHREAD_PID_OFFSET]
- str w0, [x1, #PTHREAD_TID_OFFSET]
-1:
-
/* Pick the function arg and execute. */
mov x0, x12
blr x10
ENTRY (__vfork)
- /* Save the TCB-cached PID away in w3, and then negate the TCB
- field. But if it's zero, set it to 0x80000000 instead. See
- raise.c for the logic that relies on this value. */
- mrs x2, tpidr_el0
- sub x2, x2, #PTHREAD_SIZEOF
- ldr w3, [x2, #PTHREAD_PID_OFFSET]
- mov w1, #0x80000000
- negs w0, w3
- csel w0, w1, w0, eq
- str w0, [x2, #PTHREAD_PID_OFFSET]
-
mov x0, #0x4111 /* CLONE_VM | CLONE_VFORK | SIGCHLD */
mov x1, sp
DO_CALL (clone, 2)
- /* Restore the original value of the TCB cache of the PID, if we're
- the parent. But in the child (syscall return value equals zero),
- leave things as they are. */
- cbz x0, 1f
- str w3, [x2, #PTHREAD_PID_OFFSET]
-1:
cmn x0, #4095
b.cs .Lsyscall_error
RET
cfi_def_cfa_register(fp)
cfi_undefined(ra)
- /* Check and see if we need to reset the PID. */
- ldq t0, 16(sp)
- lda t1, CLONE_VM
- and t0, t1, t2
- beq t2, 2f
-1:
-
/* Load up the arguments. */
ldq pv, 0(sp)
ldq a0, 8(sp)
halt
.align 4
-2:
- rduniq
- mov v0, s0
- lda v0, __NR_getxpid
- callsys
-3:
- stl v0, PID_OFFSET(s0)
- stl v0, TID_OFFSET(s0)
- br 1b
cfi_endproc
.end thread_start
rduniq
mov v0, a1
- /* Save the TCB-cached PID away in A2, and then negate the TCB
- field. But if it's zero, set it to 0x80000000 instead. See
- raise.c for the logic that relies on this value. */
- ldl a2, PID_OFFSET(v0)
- ldah t0, -0x8000
- negl a2, t1
- cmovne a2, t1, t0
- stl t0, PID_OFFSET(v0);
-
lda v0, SYS_ify(vfork)
call_pal PAL_callsys
- /* Restore the original value of the TCB cache of the PID, if we're
- the parent. But in the child (syscall return value equals zero),
- leave things as they are. */
- beq v0, 1f
- stl a2, PID_OFFSET(a1)
-1:
/* Normal error check and return. */
bne a3, SYSCALL_ERROR_LABEL
ret
1:
.fnstart
.cantunwind
- tst ip, #CLONE_VM
- bne 2f
- GET_TLS (lr)
- mov r1, r0
- ldr r7, =SYS_ify(getpid)
- swi 0x0
- NEGOFF_ADJ_BASE (r1, TID_OFFSET)
- str r0, NEGOFF_OFF1 (r1, TID_OFFSET)
- str r0, NEGOFF_OFF2 (r1, PID_OFFSET, TID_OFFSET)
-2:
@ pick the function arg and call address off the stack and execute
ldr r0, [sp, #4]
ldr ip, [sp], #8
and the process ID of the new process to the old process. */
ENTRY (__vfork)
- /* Save the PID value. */
- GET_TLS (r2)
- NEGOFF_ADJ_BASE2 (r2, r0, PID_OFFSET) /* Save the TLS addr in r2. */
- ldr r3, NEGOFF_OFF1 (r2, PID_OFFSET) /* Load the saved PID. */
- rsbs r0, r3, #0 /* Negate it, and test for zero. */
- /* Use 0x80000000 if it was 0. See raise.c for how this is used. */
- it eq
- moveq r0, #0x80000000
- str r0, NEGOFF_OFF1 (r2, PID_OFFSET) /* Store the temp PID. */
-
/* The DO_CALL macro saves r7 on the stack, to enable generation
of ARM unwind info. Since the stack is initially shared between
parent and child of vfork, that saved value could be corrupted.
mov r7, ip
cfi_restore (r7)
- /* Restore the old PID value in the parent. */
- cmp r0, #0 /* If we are the parent... */
- it ne
- strne r3, NEGOFF_OFF1 (r2, PID_OFFSET) /* restore the saved PID. */
-
cmn a1, #4096
it cc
RETINSTR(cc, lr)
/* The operation failed. We have to kill the thread.
We let the normal cancellation mechanism do the work. */
+ pid_t pid = __getpid ();
INTERNAL_SYSCALL_DECL (err2);
- (void) INTERNAL_SYSCALL (tgkill, err2, 3,
- THREAD_GETMEM (THREAD_SELF, pid),
- pd->tid, SIGCANCEL);
+ (void) INTERNAL_SYSCALL_CALL (tgkill, err2, pid, pd->tid,
+ SIGCANCEL);
return INTERNAL_SYSCALL_ERRNO (res, err);
}
+++ /dev/null
-/* Copyright (C) 2003-2016 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#include <unistd.h>
-#include <tls.h>
-#include <sysdep.h>
-
-
-#if IS_IN (libc)
-static inline __attribute__((always_inline)) pid_t really_getpid (pid_t oldval);
-
-static inline __attribute__((always_inline)) pid_t
-really_getpid (pid_t oldval)
-{
- if (__glibc_likely (oldval == 0))
- {
- pid_t selftid = THREAD_GETMEM (THREAD_SELF, tid);
- if (__glibc_likely (selftid != 0))
- return selftid;
- }
-
- INTERNAL_SYSCALL_DECL (err);
- pid_t result = INTERNAL_SYSCALL (getpid, err, 0);
-
- /* We do not set the PID field in the TID here since we might be
- called from a signal handler while the thread executes fork. */
- if (oldval == 0)
- THREAD_SETMEM (THREAD_SELF, tid, result);
- return result;
-}
-#endif
-
-pid_t
-__getpid (void)
-{
-#if !IS_IN (libc)
- INTERNAL_SYSCALL_DECL (err);
- pid_t result = INTERNAL_SYSCALL (getpid, err, 0);
-#else
- pid_t result = THREAD_GETMEM (THREAD_SELF, pid);
- if (__glibc_unlikely (result <= 0))
- result = really_getpid (result);
-#endif
- return result;
-}
-
-libc_hidden_def (__getpid)
-weak_alias (__getpid, getpid)
-libc_hidden_def (getpid)
ldwm -64(%sp), %r4
.LthreadStart:
-# define CLONE_VM_BIT 23 /* 0x00000100 */
- /* Load original clone flags.
- If CLONE_VM was passed, don't modify PID/TID.
- Otherwise store the result of getpid to PID/TID. */
- ldw -56(%sp), %r26
- bb,<,n %r26, CLONE_VM_BIT, 1f
- ble 0x100(%sr2, %r0)
- ldi __NR_getpid, %r20
- mfctl %cr27, %r26
- stw %ret0, PID_THREAD_OFFSET(%r26)
- stw %ret0, TID_THREAD_OFFSET(%r26)
-1:
/* Load up the arguments. */
ldw -60(%sp), %arg0
ldw -64(%sp), %r22
replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
and the process ID of the new process to the old process. */
-/* Load the thread register.
- Load the saved PID value.
- Negate the value.
- Store the temporary PID. */
-#define SAVE_PID \
- mfctl %cr27, %r26 ASM_LINE_SEP \
- ldw PID_THREAD_OFFSET(%r26),%r1 ASM_LINE_SEP \
- sub %r0,%r1,%r1 ASM_LINE_SEP \
- stw %r1,PID_THREAD_OFFSET(%r26) ASM_LINE_SEP
-/* If we are the parent...
- Get the thread pointer.
- Load the saved PID.
- Negate the value (got back original)
- Restore the PID. */
-#define RESTORE_PID \
- cmpb,=,n %r0,%ret0,.Lthread_start ASM_LINE_SEP \
- mfctl %cr27, %r26 ASM_LINE_SEP \
- ldw PID_THREAD_OFFSET(%r26),%r1 ASM_LINE_SEP \
- sub %r0,%r1,%r1 ASM_LINE_SEP \
- stw %r1,PID_THREAD_OFFSET(%r26) ASM_LINE_SEP \
.Lthread_start: ASM_LINE_SEP
/* r26, r25, r24, r23 are free since vfork has no arguments */
copy %r19, %r25 /* parent */
#endif
- /* Save the process PID */
- SAVE_PID
-
/* Syscall saves and restores all register states */
ble 0x100(%sr2,%r0)
ldi __NR_vfork,%r20
- /* Conditionally restore the PID */
- RESTORE_PID
-
/* Check for error */
ldi -4096,%r1
comclr,>>= %r1,%ret0,%r0 /* Note: unsigned compare. */
cfi_undefined (eip);
/* Note: %esi is zero. */
movl %esi,%ebp /* terminate the stack frame */
- testl $CLONE_VM, %edi
- je L(newpid)
-L(haspid):
call *%ebx
#ifdef PIC
call L(here)
movl $SYS_ify(exit), %eax
ENTER_KERNEL
- .subsection 2
-L(newpid):
- movl $SYS_ify(getpid), %eax
- ENTER_KERNEL
-L(nomoregetpid):
- movl %eax, %gs:PID
- movl %eax, %gs:TID
- jmp L(haspid)
- .previous
- cfi_endproc;
-
- cfi_startproc
PSEUDO_END (__clone)
libc_hidden_def (__clone)
cfi_adjust_cfa_offset (-4)
cfi_register (%eip, %ecx)
- /* Save the TCB-cached PID away in %edx, and then negate the TCB
- field. But if it's zero, set it to 0x80000000 instead. See
- raise.c for the logic that relies on this value. */
- movl %gs:PID, %edx
- movl %edx, %eax
- negl %eax
- jne 1f
- movl $0x80000000, %eax
-1: movl %eax, %gs:PID
-
-
/* Stuff the syscall number in EAX and enter into the kernel. */
movl $SYS_ify (vfork), %eax
int $0x80
pushl %ecx
cfi_adjust_cfa_offset (4)
- /* Restore the original value of the TCB cache of the PID, if we're
- the parent. But in the child (syscall return value equals zero),
- leave things as they are. */
- testl %eax, %eax
- je 1f
- movl %edx, %gs:PID
-1:
-
cmpl $-4095, %eax
/* Branch forward if it failed. */
jae SYSCALL_ERROR_LABEL
(CHILD) mov loc0=gp
(PARENT) ret
;;
- tbit.nz p6,p0=in3,8 /* CLONE_VM */
-(p6) br.cond.dptk 1f
- ;;
- mov r15=SYS_ify (getpid)
-(p7) break __BREAK_SYSCALL
- ;;
- add r9=PID,r13
- add r10=TID,r13
- ;;
- st4 [r9]=r8
- st4 [r10]=r8
- ;;
-1: ld8 out1=[in0],8 /* Retrieve code pointer. */
+ ld8 out1=[in0],8 /* Retrieve code pointer. */
mov out0=in4 /* Pass proper argument to fn */
;;
ld8 gp=[in0] /* Load function gp. */
.prologue // work around a GAS bug which triggers if
.body // first .prologue is not at the beginning of proc.
alloc r2=ar.pfs,0,0,2,0
- adds r14=PID,r13
- ;;
- ld4 r16=[r14]
- ;;
- sub r15=0,r16
- cmp.eq p6,p0=0,r16
- ;;
-(p6) movl r15=0x80000000
mov out0=CLONE_VM+CLONE_VFORK+SIGCHLD
mov out1=0 /* Standard sp value. */
;;
- st4 [r14]=r15
DO_CALL (SYS_ify (clone))
cmp.eq p6,p0=0,r8
- adds r14=PID,r13
(p6) br.cond.dptk 1f
- ;;
- ld4 r15=[r14]
- ;;
- extr.u r16=r15,0,31
- ;;
- cmp.eq p0,p6=0,r16
- ;;
-(p6) sub r16=0,r15
- ;;
- st4 [r14]=r16
1:
cmp.eq p6,p0=-1,r10
(p6) br.cond.spnt.few __syscall_error
cfi_startproc
cfi_undefined (pc) /* Mark end of stack */
subl %fp, %fp /* terminate the stack frame */
- /* Check and see if we need to reset the PID. */
- andl #CLONE_VM, %d1
- jne 1f
- movel #SYS_ify (getpid), %d0
- trap #0
- movel %a0, -(%sp)
- movel %d0, -(%sp)
- bsrl __m68k_read_tp@PLTPC
- movel (%sp)+, %d0
- movel %d0, PID_OFFSET(%a0)
- movel %d0, TID_OFFSET(%a0)
- movel (%sp)+, %a0
-1:
jsr (%a0)
movel %d0, %d1
movel #SYS_ify (exit), %d0
ENTRY (__vfork)
- /* Save the TCB-cached PID away in %d1, and then negate the TCB
- field. But if it's zero, set it to 0x80000000 instead. See
- raise.c for the logic that relies on this value. */
- jbsr __m68k_read_tp@PLTPC
- movel %a0, %a1
- movel PID_OFFSET(%a1), %d0
- movel %d0, %d1
- negl %d0
- jne 1f
- movel #0x80000000, %d0
-1: movel %d0, PID_OFFSET(%a1)
-
/* Pop the return PC value into A0. */
movel %sp@+, %a0
cfi_adjust_cfa_offset (-4)
movel #SYS_ify (vfork), %d0
trap #0
- /* Restore the original value of the TCB cache of the PID, if we're
- the parent. But in the child (syscall return value equals zero),
- leave things as they are. */
- tstl %d0
- jeq 1f
- movel %d1, PID_OFFSET(%a1)
-1:
-
tstl %d0
jmi .Lerror /* Branch forward if it failed. */
SAVE_GP (GPOFF)
/* The stackframe has been created on entry of clone(). */
- /* Check and see if we need to reset the PID. */
- and a1,a0,CLONE_VM
- beqz a1,L(restore_pid)
-L(donepid):
-
/* Restore the arg for user's function. */
PTR_L t9,0(sp) /* Function pointer. */
PTR_L a0,PTRSIZE(sp) /* Argument pointer. */
jal _exit
#endif
-L(restore_pid):
- li v0,__NR_getpid
- syscall
- READ_THREAD_POINTER(v1)
- INT_S v0,PID_OFFSET(v1)
- INT_S v0,TID_OFFSET(v1)
- b L(donepid)
-
END(__thread_start)
libc_hidden_def (__clone)
PTR_ADDU sp, FRAMESZ
cfi_adjust_cfa_offset (-FRAMESZ)
- /* Save the PID value. */
- READ_THREAD_POINTER(v1) /* Get the thread pointer. */
- lw a2, PID_OFFSET(v1) /* Load the saved PID. */
- subu a2, $0, a2 /* Negate it. */
- bnez a2, 1f /* If it was zero... */
- lui a2, 0x8000 /* use 0x80000000 instead. */
-1: sw a2, PID_OFFSET(v1) /* Store the temporary PID. */
-
li a0, 0x4112 /* CLONE_VM | CLONE_VFORK | SIGCHLD */
move a1, sp
li v0,__NR_clone
syscall
- /* Restore the old PID value in the parent. */
- beqz v0, 1f /* If we are the parent... */
- READ_THREAD_POINTER(v1) /* Get the thread pointer. */
- lw a2, PID_OFFSET(v1) /* Load the saved PID. */
- subu a2, $0, a2 /* Re-negate it. */
- lui a0, 0x8000 /* Load 0x80000000... */
- bne a2, a0, 2f /* ... compare against it... */
- li a2, 0 /* ... use 0 instead. */
-2: sw a2, PID_OFFSET(v1) /* Restore the PID. */
-1:
-
cfi_remember_state
bnez a3,L(error)
cfi_startproc
cfi_undefined (ra)
- /* We expect the argument registers to be preserved across system
- calls and across task cloning, so flags should be in r4 here. */
- andi r2, r4, CLONE_VM
- bne r2, zero, 2f
- DO_CALL (getpid, 0)
- stw r2, PID_OFFSET(r23)
- stw r2, TID_OFFSET(r23)
-2:
ldw r5, 4(sp) /* Function pointer. */
ldw r4, 0(sp) /* Argument pointer. */
addi sp, sp, 8
ENTRY(__vfork)
- ldw r6, PID_OFFSET(r23)
- sub r7, zero, r6
- bne r7, zero, 2f
- movhi r7, %hi(0x80000000)
-2:
- stw r7, PID_OFFSET(r23)
-
movi r4, 0x4111 /* (CLONE_VM | CLONE_VFORK | SIGCHLD) */
mov r5, zero
DO_CALL (clone, 2)
- beq r2, zero, 1f
- stw r6, PID_OFFSET(r23)
-1:
bne r7, zero, SYSCALL_ERROR_LABEL
ret
crandc cr1*4+eq,cr1*4+eq,cr0*4+so
bne- cr1,L(parent) /* The '-' is to minimise the race. */
- /* If CLONE_VM is set do not update the pid/tid field. */
- andi. r0,r28,CLONE_VM
- bne+ cr0,L(oldpid)
-
- DO_CALL(SYS_ify(getpid))
- stw r3,TID(r2)
- stw r3,PID(r2)
-L(oldpid):
-
/* Call procedure. */
mtctr r30
mr r3,r31
ENTRY (__vfork)
- /* Load the TCB-cached PID value and negates it. If It it is zero
- sets it to 0x800000. And then sets its value again on TCB field.
- See raise.c for the logic that relies on this value. */
-
- lwz r0,PID(r2)
- cmpwi cr0,r0,0
- neg r0,r0
- bne- cr0,1f
- lis r0,0x8000
-1: stw r0,PID(r2)
-
DO_CALL (SYS_ify (vfork))
- cmpwi cr1,r3,0
- beqlr- 1
-
- /* Restore the original value of the TCB cache of the PID, if we're
- the parent. But in the child (syscall return value equals zero),
- leave things as they are. */
- lwz r0,PID(r2)
- /* Cannot use clrlwi. here, because cr0 needs to be preserved
- until PSEUDO_RET. */
- clrlwi r4,r0,1
- cmpwi cr1,r4,0
- beq- cr1,1f
- neg r4,r0
-1: stw r4,PID(r2)
-
PSEUDO_RET
PSEUDO_END (__vfork)
crandc cr1*4+eq,cr1*4+eq,cr0*4+so
bne- cr1,L(parent) /* The '-' is to minimise the race. */
- /* If CLONE_VM is set do not update the pid/tid field. */
- rldicl. r0,r29,56,63 /* flags & CLONE_VM. */
- bne+ cr0,L(oldpid)
-
- DO_CALL(SYS_ify(getpid))
- stw r3,TID(r13)
- stw r3,PID(r13)
-L(oldpid):
-
std r2,FRAME_TOC_SAVE(r1)
/* Call procedure. */
PPC64_LOAD_FUNCPTR r30
ENTRY (__vfork)
CALL_MCOUNT 0
- /* Load the TCB-cached PID value and negates it. If It it is zero
- sets it to 0x800000. And then sets its value again on TCB field.
- See raise.c for the logic that relies on this value. */
- lwz r0,PID(r13)
- cmpwi cr0,r0,0
- neg r0,r0
- bne- cr0,1f
- lis r0,0x8000
-1: stw r0,PID(r13)
-
DO_CALL (SYS_ify (vfork))
- cmpwi cr1,r3,0
- beqlr- 1
-
- /* Restore the original value of the TCB cache of the PID, if we're
- the parent. But in the child (syscall return value equals zero),
- leave things as they are. */
- lwz r0,PID(r13)
- clrlwi r4,r0,1
- cmpwi cr1,r4,0
- beq- cr1,1f
- neg r4,r0
-1: stw r4,PID(r13)
-
PSEUDO_RET
PSEUDO_END (__vfork)
__pthread_initialize_pids (struct pthread *pd)
{
INTERNAL_SYSCALL_DECL (err);
- pd->pid = pd->tid = INTERNAL_SYSCALL (set_tid_address, err, 1, &pd->tid);
+ pd->tid = INTERNAL_SYSCALL_CALL (set_tid_address, err, &pd->tid);
}
#include <pthreadP.h>
#include <tls.h>
#include <sysdep.h>
+#include <unistd.h>
int
/* We have a special syscall to do the work. */
INTERNAL_SYSCALL_DECL (err);
- /* One comment: The PID field in the TCB can temporarily be changed
- (in fork). But this must not affect this code here. Since this
- function would have to be called while the thread is executing
- fork, it would have to happen in a signal handler. But this is
- no allowed, pthread_kill is not guaranteed to be async-safe. */
- int val;
- val = INTERNAL_SYSCALL (tgkill, err, 3, THREAD_GETMEM (THREAD_SELF, pid),
- tid, signo);
+ pid_t pid = __getpid ();
+ int val = INTERNAL_SYSCALL_CALL (tgkill, err, pid, tid, signo);
return (INTERNAL_SYSCALL_ERROR_P (val, err)
? INTERNAL_SYSCALL_ERRNO (val, err) : 0);
}
if (signo == SIGCANCEL || signo == SIGTIMER || signo == SIGSETXID)
return EINVAL;
+ pid_t pid = getpid ();
+
/* Set up the siginfo_t structure. */
siginfo_t info;
memset (&info, '\0', sizeof (siginfo_t));
info.si_signo = signo;
info.si_code = SI_QUEUE;
- info.si_pid = THREAD_GETMEM (THREAD_SELF, pid);
+ info.si_pid = pid;
info.si_uid = getuid ();
info.si_value = value;
/* We have a special syscall to do the work. */
INTERNAL_SYSCALL_DECL (err);
- /* One comment: The PID field in the TCB can temporarily be changed
- (in fork). But this must not affect this code here. Since this
- function would have to be called while the thread is executing
- fork, it would have to happen in a signal handler. But this is
- no allowed, pthread_sigqueue is not guaranteed to be async-safe. */
- int val = INTERNAL_SYSCALL (rt_tgsigqueueinfo, err, 4,
- THREAD_GETMEM (THREAD_SELF, pid),
- tid, signo, &info);
-
+ int val = INTERNAL_SYSCALL_CALL (rt_tgsigqueueinfo, err, pid, tid, signo,
+ &info);
return (INTERNAL_SYSCALL_ERROR_P (val, err)
? INTERNAL_SYSCALL_ERRNO (val, err) : 0);
#else
int
raise (int sig)
{
- /* raise is an async-safe function so it could be called while the
- fork/vfork function temporarily invalidated the PID field. To avoid
- relying on cached value we block all user-defined signal handler
- (which might call fork/vfork) and issue the getpid and gettid
- syscalls directly. */
-
-
/* rt_sigprocmask may fail if:
1. sigsetsize != sizeof (sigset_t) (EINVAL)
PSEUDO_END (__clone)
thread_start:
- tml %r3,256 /* CLONE_VM == 0x00000100 */
- jne 1f
- svc SYS_ify(getpid)
- ear %r3,%a0
- st %r2,PID(%r3)
- st %r2,TID(%r3)
-1:
/* fn is in gpr 1, arg in gpr 0 */
lr %r2,%r0 /* set first parameter to void *arg */
ahi %r15,-96 /* make room on the stack for the save area */
and the process ID of the new process to the old process. */
ENTRY (__libc_vfork)
- ear %r4,%a0
- lhi %r1,1
- icm %r3,15,PID(%r4)
- sll %r1,31
- je 1f
- lcr %r1,%r3
-1: st %r1,PID(%r4)
-
/* Do vfork system call. */
svc SYS_ify (vfork)
- ltr %r2,%r2
- je 1f
- st %r3,PID(%r4)
-1:
/* Check for error. */
lhi %r4,-4095
clr %r2,%r4
PSEUDO_END (__clone)
thread_start:
- tmll %r3,256 /* CLONE_VM == 0x00000100 */
- jne 1f
- svc SYS_ify(getpid)
- ear %r3,%a0
- sllg %r3,%r3,32
- ear %r3,%a1
- st %r2,PID(%r3)
- st %r2,TID(%r3)
-1:
/* fn is in gpr 1, arg in gpr 0 */
lgr %r2,%r0 /* set first parameter to void *arg */
aghi %r15,-160 /* make room on the stack for the save area */
and the process ID of the new process to the old process. */
ENTRY (__libc_vfork)
- ear %r4,%a0
- sllg %r4,%r4,32
- ear %r4,%a1
- icm %r3,15,PID(%r4)
- llilh %r1,32768
- je 1f
- lcr %r1,%r3
-1: st %r1,PID(%r4)
-
/* Do vfork system call. */
svc SYS_ify (vfork)
- ltgr %r2,%r2
- je 1f
- st %r3,PID(%r4)
-1:
/* Check for error. */
lghi %r4,-4095
clgr %r2,%r4
2:
/* terminate the stack frame */
mov #0, r14
- mov r4, r0
- shlr8 r0
- tst #1, r0 // CLONE_VM = (1 << 8)
- bf/s 4f
- mov r4, r0
- /* new pid */
- mov #+SYS_ify(getpid), r3
- trapa #0x15
-3:
- stc gbr, r1
- mov.w .Lpidoff, r2
- add r1, r2
- mov.l r0, @r2
- mov.w .Ltidoff, r2
- add r1, r2
- mov.l r0, @r2
-4:
+
/* thread starts */
mov.l @r15, r1
jsr @r1
.long _GLOBAL_OFFSET_TABLE_
.L3:
.long PLTJMP(C_SYMBOL_NAME(_exit))
-.Lpidoff:
- .word PID - TLS_PRE_TCB_SIZE
-.Ltidoff:
- .word TID - TLS_PRE_TCB_SIZE
PSEUDO_END (__clone)
libc_hidden_def (__clone)
and the process ID of the new process to the old process. */
ENTRY (__libc_vfork)
- /* Save the PID value. */
- stc gbr, r2
- mov.w .L2, r0
- mov.l @(r0,r2), r4
- neg r4, r1
- tst r1, r1
- bf 1f
- mov #1, r1
- rotr r1
-1:
- mov.l r1, @(r0,r2)
mov.w .L1, r3
trapa #0x10
mov r0, r1
- /* Restore the old PID value in the parent. */
- tst r0, r0
- bt.s 2f
- stc gbr, r2
- mov.w .L2, r0
- mov.l r4, @(r0,r2)
- mov r1, r0
-2:
mov #-12, r2
shad r2, r1
not r1, r1 // r1=0 means r0 = -1 to -4095
nop
.L1:
.word __NR_vfork
-.L2:
- .word PID - TLS_PRE_TCB_SIZE
.align 2
PSEUDO_END (__libc_vfork)
.type __thread_start,@function
__thread_start:
- andcc %g4, CLONE_VM, %g0
- bne 1f
- set __NR_getpid,%g1
- ta 0x10
- st %o0,[%g7 + PID]
- st %o0,[%g7 + TID]
-1:
mov %g0, %fp /* terminate backtrace */
call %g2
mov %g3,%o0
.text
.globl __syscall_error
ENTRY(__libc_vfork)
- ld [%g7 + PID], %o5
- cmp %o5, 0
- bne 1f
- sub %g0, %o5, %o4
- sethi %hi(0x80000000), %o4
-1: st %o4, [%g7 + PID]
-
LOADSYSCALL(vfork)
ta 0x10
bcc 2f
mov %o7, %g1
- st %o5, [%g7 + PID]
call __syscall_error
mov %g1, %o7
2: sub %o1, 1, %o1
andcc %o0, %o1, %o0
- bne,a 1f
- st %o5, [%g7 + PID]
1: retl
nop
END(__libc_vfork)
.type __thread_start,@function
__thread_start:
- andcc %g4, CLONE_VM, %g0
- bne,pt %icc, 1f
- set __NR_getpid,%g1
- ta 0x6d
- st %o0,[%g7 + PID]
- st %o0,[%g7 + TID]
-1:
mov %g0, %fp /* terminate backtrace */
call %g2
mov %g3,%o0
.text
.globl __syscall_error
ENTRY(__libc_vfork)
- ld [%g7 + PID], %o5
- sethi %hi(0x80000000), %o3
- cmp %o5, 0
- sub %g0, %o5, %o4
- move %icc, %o3, %o4
- st %o4, [%g7 + PID]
-
LOADSYSCALL(vfork)
ta 0x6d
bcc,pt %xcc, 2f
mov %o7, %g1
- st %o5, [%g7 + PID]
call __syscall_error
mov %g1, %o7
2: sub %o1, 1, %o1
andcc %o0, %o1, %o0
- bne,a,pt %icc, 1f
- st %o5, [%g7 + PID]
1: retl
nop
END(__libc_vfork)
fdatasync - fdatasync Ci:i fdatasync
flock - flock i:ii __flock flock
get_kernel_syms EXTRA get_kernel_syms i:p __compat_get_kernel_syms get_kernel_syms@GLIBC_2.0:GLIBC_2.23
+getpid - getpid Ei: __getpid getpid
getegid - getegid Ei: __getegid getegid
geteuid - geteuid Ei: __geteuid geteuid
getpgid - getpgid i:i __getpgid getpgid
.Lthread_start:
cfi_def_cfa_offset (FRAME_SIZE)
cfi_undefined (lr)
- /* Check and see if we need to reset the PID, which we do if
- CLONE_VM isn't set, i.e. it's a fork-like clone with a new
- address space. In that case we update the cached values
- from the true system pid (retrieved via __NR_getpid syscall). */
- moveli r0, CLONE_VM
- and r0, r30, r0
- BNEZ r0, .Lno_reset_pid /* CLONE_VM is set */
- moveli TREG_SYSCALL_NR_NAME, __NR_getpid
- swint1
- ADDLI_PTR r2, tp, PID_OFFSET
- {
- ST4 r2, r0
- ADDLI_PTR r2, tp, TID_OFFSET
- }
- ST4 r2, r0
-.Lno_reset_pid:
{
/* Invoke user function with specified argument. */
move r0, r31
.text
ENTRY (__vfork)
- {
- addli r11, tp, PID_OFFSET /* Point at PID. */
- movei r13, 1
- }
- {
- LD4U r12, r11 /* Load the saved PID. */
- shli r13, r13, 31 /* Build 0x80000000. */
- }
- sub r12, zero, r12 /* Negate it. */
- CMOVEQZ r12, r12, r13 /* Replace zero pids. */
- ST4 r11, r12 /* Store the temporary PID. */
-
{
moveli r0, CLONE_VFORK | CLONE_VM | SIGCHLD
move r1, zero
moveli TREG_SYSCALL_NR_NAME, __NR_clone
swint1
- BEQZ r0, 1f /* If we are the parent... */
- {
- addli r11, tp, PID_OFFSET /* Point at PID. */
- movei r13, 1
- }
- {
- LD4U r12, r11 /* Load the saved PID. */
- shli r13, r13, 31 /* Build 0x80000000. */
- }
- {
- CMPEQ r13, r12, r12 /* Test for that value. */
- sub r12, zero, r12 /* Re-negate it. */
- }
- CMOVNEZ r12, r13, zero /* Replace zero pids. */
- ST4 r11, r12 /* Restore the PID. */
-1:
BNEZ r1, 0f
jrp lr
PSEUDO_END (__vfork)
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
+#include <sys/syscall.h>
-#include <tls.h> /* for THREAD_* macros. */
+#include <stackinfo.h> /* For _STACK_GROWS_{UP,DOWN}. */
+
+static int do_test (void);
+
+#define TEST_FUNCTION do_test ()
+#include <test-skeleton.c>
static int sig;
static int pipefd[2];
{
close (pipefd[0]);
- pid_t pid = THREAD_GETMEM (THREAD_SELF, pid);
- pid_t tid = THREAD_GETMEM (THREAD_SELF, tid);
+ pid_t ppid = getppid ();
+ pid_t pid = getpid ();
+ pid_t tid = syscall (__NR_gettid);
- while (write (pipefd[1], &pid, sizeof pid) < 0)
- continue;
- while (write (pipefd[1], &tid, sizeof tid) < 0)
- continue;
+ if (write (pipefd[1], &ppid, sizeof ppid) != sizeof (ppid))
+ FAIL_EXIT1 ("write ppid failed\n");
+ if (write (pipefd[1], &pid, sizeof pid) != sizeof (pid))
+ FAIL_EXIT1 ("write pid failed\n");
+ if (write (pipefd[1], &tid, sizeof tid) != sizeof (tid))
+ FAIL_EXIT1 ("write tid failed\n");
return 0;
}
static int
-clone_test (int clone_flags)
+do_test (void)
{
sig = SIGRTMIN;
sigset_t ss;
sigemptyset (&ss);
sigaddset (&ss, sig);
if (sigprocmask (SIG_BLOCK, &ss, NULL) != 0)
- {
- printf ("sigprocmask failed: %m\n");
- return 1;
- }
+ FAIL_EXIT1 ("sigprocmask failed: %m");
if (pipe2 (pipefd, O_CLOEXEC))
- {
- printf ("sigprocmask failed: %m\n");
- return 1;
- }
-
- pid_t ppid = getpid ();
+ FAIL_EXIT1 ("pipe failed: %m");
+ int clone_flags = 0;
#ifdef __ia64__
extern int __clone2 (int (*__fn) (void *__arg), void *__child_stack_base,
size_t __child_stack_size, int __flags,
#error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
#endif
#endif
+
close (pipefd[1]);
if (p == -1)
+ FAIL_EXIT1("clone failed: %m");
+
+ pid_t ppid, pid, tid;
+ if (read (pipefd[0], &ppid, sizeof pid) != sizeof pid)
{
- printf ("clone failed: %m\n");
- return 1;
+ kill (p, SIGKILL);
+ FAIL_EXIT1 ("read ppid failed: %m");
}
-
- pid_t pid, tid;
if (read (pipefd[0], &pid, sizeof pid) != sizeof pid)
{
- printf ("read pid failed: %m\n");
kill (p, SIGKILL);
- return 1;
+ FAIL_EXIT1 ("read pid failed: %m");
}
if (read (pipefd[0], &tid, sizeof tid) != sizeof tid)
{
- printf ("read pid failed: %m\n");
kill (p, SIGKILL);
- return 1;
+ FAIL_EXIT1 ("read tid failed: %m");
}
close (pipefd[0]);
int ret = 0;
- /* For CLONE_VM glibc clone implementation does not change the pthread
- pid/tid field. */
- if ((clone_flags & CLONE_VM) == CLONE_VM)
- {
- if ((ppid != pid) || (ppid != tid))
- {
- printf ("parent pid (%i) != received pid/tid (%i/%i)\n",
- (int)ppid, (int)pid, (int)tid);
- ret = 1;
- }
- }
- /* For any other flag clone updates the new pthread pid and tid with
- the clone return value. */
- else
- {
- if ((p != pid) || (p != tid))
- {
- printf ("child pid (%i) != received pid/tid (%i/%i)\n",
- (int)p, (int)pid, (int)tid);
- ret = 1;
- }
- }
+ pid_t own_pid = getpid ();
+ pid_t own_tid = syscall (__NR_gettid);
+
+ /* Some sanity checks for clone syscall: returned ppid should be current
+ pid and both returned tid/pid should be different from current one. */
+ if ((ppid != own_pid) || (pid == own_pid) || (tid == own_tid))
+ FAIL_RET ("ppid=%i pid=%i tid=%i | own_pid=%i own_tid=%i",
+ (int)ppid, (int)pid, (int)tid, (int)own_pid, (int)own_tid);
int e;
if (waitpid (p, &e, __WCLONE) != p)
{
- puts ("waitpid failed");
kill (p, SIGKILL);
- return 1;
+ FAIL_EXIT1 ("waitpid failed");
}
if (!WIFEXITED (e))
{
printf ("died from signal %s\n", strsignal (WTERMSIG (e)));
else
puts ("did not terminate correctly");
- return 1;
+ exit (EXIT_FAILURE);
}
if (WEXITSTATUS (e) != 0)
- {
- printf ("exit code %d\n", WEXITSTATUS (e));
- return 1;
- }
+ FAIL_EXIT1 ("exit code %d", WEXITSTATUS (e));
return ret;
}
-
-int
-do_test (void)
-{
- /* First, check that the clone implementation, without any flag, updates
- the struct pthread to contain the new PID and TID. */
- int ret = clone_test (0);
- /* Second, check that with CLONE_VM the struct pthread PID and TID fields
- remain unmodified after the clone. Any modifications would cause problem
- for the parent as described in bug 19957. */
- ret += clone_test (CLONE_VM);
- return ret;
-}
-
-#define TEST_FUNCTION do_test ()
-#include "../test-skeleton.c"
the outermost frame obviously. */
xorl %ebp, %ebp
- andq $CLONE_VM, %rdi
- jne 1f
- movl $SYS_ify(getpid), %eax
- syscall
- movl %eax, %fs:PID
- movl %eax, %fs:TID
-1:
-
/* Set up arguments for the function call. */
popq %rax /* Function to call. */
popq %rdi /* Argument. */
cfi_adjust_cfa_offset(-8)
cfi_register(%rip, %rdi)
- /* Save the TCB-cached PID away in %esi, and then negate the TCB
- field. But if it's zero, set it to 0x80000000 instead. See
- raise.c for the logic that relies on this value. */
- movl %fs:PID, %esi
- movl $0x80000000, %ecx
- movl %esi, %edx
- negl %edx
- cmove %ecx, %edx
- movl %edx, %fs:PID
-
/* Stuff the syscall number in RAX and enter into the kernel. */
movl $SYS_ify (vfork), %eax
syscall
pushq %rdi
cfi_adjust_cfa_offset(8)
- /* Restore the original value of the TCB cache of the PID, if we're
- the parent. But in the child (syscall return value equals zero),
- leave things as they are. */
- testq %rax, %rax
- je 1f
- movl %esi, %fs:PID
-1:
-
cmpl $-4095, %eax
jae SYSCALL_ERROR_LABEL /* Branch forward if it failed. */
RESULT offsetof (struct pthread, result)
TID offsetof (struct pthread, tid)
-PID offsetof (struct pthread, pid)
CANCELHANDLING offsetof (struct pthread, cancelhandling)
CLEANUP_JMP_BUF offsetof (struct pthread, cleanup_jmp_buf)
CLEANUP offsetof (struct pthread, cleanup)
projects / thirdparty / glibc.git / commitdiff
