dump: Merge thread and task parasite-core info dumping

There are parts dumping which is common to thread and task,
and this stuff is represented by parasite_dump_thread structure.

Merge this into parasite_dump_misc and facror out dumping code.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-dump.c

@@ -626,13 +626,20 @@ static int dump_task_ids(struct pstree_item *item, const struct cr_fdset *cr_fds
 	return pb_write_one(fdset_fd(cr_fdset, CR_FD_IDS), item->ids, PB_IDS);
 }
 
-static int dump_thread_core(int pid, ThreadCoreEntry *tc)
+int dump_thread_core(int pid, CoreEntry *core, const struct parasite_dump_thread *ti)
 {
 	int ret;
+	ThreadCoreEntry *tc = core->thread_core;
 
 	ret = get_task_futex_robust_list(pid, tc);
 	if (!ret)
 		ret = dump_sched_info(pid, tc);
+	if (!ret) {
+		core_put_tls(core, ti->tls);
+		CORE_THREAD_ARCH_INFO(core)->clear_tid_addr = encode_pointer(ti->tid_addr);
+		BUG_ON(!tc->sas);
+		copy_sas(tc->sas, &ti->sas);
+	}
 
 	return ret;
 }
@@ -657,20 +664,13 @@ static int dump_task_core_all(struct parasite_ctl *ctl,
 
 	strncpy((char *)core->tc->comm, stat->comm, TASK_COMM_LEN);
 	core->tc->flags = stat->flags;
-
 	core->tc->task_state = TASK_ALIVE;
 	core->tc->exit_code = 0;
 
-	ret = dump_thread_core(pid, core->thread_core);
+	ret = dump_thread_core(pid, core, &misc->ti);
 	if (ret)
 		goto err;
 
-	core_put_tls(core, misc->tls);
-	CORE_THREAD_ARCH_INFO(core)->clear_tid_addr = encode_pointer(misc->tid_addr);
-
-	BUG_ON(!core->thread_core->sas);
-	copy_sas(core->thread_core->sas, &misc->sas);
-
 	ret = pb_write_one(fd_core, core, PB_CORE);
 	if (ret < 0)
 		goto err;
@@ -1099,10 +1099,6 @@ static int dump_task_thread(struct parasite_ctl *parasite_ctl,
 		goto err;
 	}
 
-	ret = dump_thread_core(pid, core->thread_core);
-	if (ret)
-		goto err;
-
 	fd_core = open_image(CR_FD_CORE, O_DUMP, tid->virt);
 	if (fd_core < 0)
 		goto err;

include/parasite-syscall.h

@@ -73,6 +73,7 @@ extern int parasite_dump_misc_seized(struct parasite_ctl *ctl, struct parasite_d
 extern int parasite_dump_creds(struct parasite_ctl *ctl, struct _CredsEntry *ce);
 extern int parasite_dump_thread_seized(struct parasite_ctl *ctl, int id,
 					struct pid *tid, struct _CoreEntry *core);
+extern int dump_thread_core(int pid, CoreEntry *core, const struct parasite_dump_thread *dt);
 
 extern int parasite_drain_fds_seized(struct parasite_ctl *ctl,
 					struct parasite_drain_fd *dfds,

include/parasite.h

@@ -128,6 +128,13 @@ static inline int posix_timers_dump_size(int timer_n)
 	return sizeof(int) + sizeof(struct posix_timer) * timer_n;
 }
 
+struct parasite_dump_thread {
+	unsigned int		*tid_addr;
+	pid_t			tid;
+	u32			tls;
+	stack_t			sas;
+};
+
 /*
  * Misc sfuff, that is too small for separate file, but cannot
  * be read w/o using parasite
@@ -135,15 +142,13 @@ static inline int posix_timers_dump_size(int timer_n)
 
 struct parasite_dump_misc {
 	unsigned long		brk;
-	unsigned int		*tid_addr;
 
 	u32 pid;
 	u32 sid;
 	u32 pgid;
-	u32 tls;
 	u32 umask;
 
-	stack_t			sas;
+	struct parasite_dump_thread	ti;
 };
 
 #define PARASITE_MAX_GROUPS	(PAGE_SIZE / sizeof(unsigned int) - 2 * sizeof(unsigned))
@@ -154,13 +159,6 @@ struct parasite_dump_creds {
 	unsigned int		groups[PARASITE_MAX_GROUPS];
 };
 
-struct parasite_dump_thread {
-	unsigned int		*tid_addr;
-	pid_t			tid;
-	u32			tls;
-	stack_t			sas;
-};
-
 static inline void copy_sas(ThreadSasEntry *dst, const stack_t *src)
 {
 	dst->ss_sp = encode_pointer(src->ss_sp);

parasite-syscall.c

@@ -482,14 +482,8 @@ int parasite_dump_thread_seized(struct parasite_ctl *ctl, int id,
 		return -1;
 	}
 
-	BUG_ON(!tc->sas);
-	copy_sas(tc->sas, &args->sas);
-
-	CORE_THREAD_ARCH_INFO(core)->clear_tid_addr = encode_pointer(args->tid_addr);
 	tid->virt = args->tid;
-	core_put_tls(core, args->tls);
-
-	return 0;
+	return dump_thread_core(pid, core, args);
 }
 
 int parasite_dump_sigacts_seized(struct parasite_ctl *ctl, struct cr_fdset *cr_fdset)

pie/parasite.c

@@ -136,26 +136,29 @@ static int dump_posix_timers(struct parasite_dump_posix_timers_args *args)
 	return ret;
 }
 
-static int dump_misc(struct parasite_dump_misc *args)
+static int dump_thread_common(struct parasite_dump_thread *ti)
 {
 	int ret;
 
+	ti->tls = arch_get_tls();
+	ret = sys_prctl(PR_GET_TID_ADDRESS, (unsigned long) &ti->tid_addr, 0, 0, 0);
+	if (ret == 0)
+		ret = sys_sigaltstack(NULL, &ti->sas);
+
+	return ret;
+}
+
+static int dump_misc(struct parasite_dump_misc *args)
+{
 	args->brk = sys_brk(0);
 
 	args->pid = sys_getpid();
 	args->sid = sys_getsid();
 	args->pgid = sys_getpgid(0);
-	args->tls = arch_get_tls();
 	args->umask = sys_umask(0);
 	sys_umask(args->umask); /* never fails */
 
-	ret = sys_sigaltstack(NULL, &args->sas);
-	if (ret)
-		return ret;
-
-	ret = sys_prctl(PR_GET_TID_ADDRESS, (unsigned long) &args->tid_addr, 0, 0, 0);
-
-	return ret;
+	return dump_thread_common(&args->ti);
 }
 
 static int dump_creds(struct parasite_dump_creds *args)
@@ -205,19 +208,8 @@ static int drain_fds(struct parasite_drain_fd *args)
 
 static int dump_thread(struct parasite_dump_thread *args)
 {
-	pid_t tid = sys_gettid();
-	int ret;
-
-	ret = sys_prctl(PR_GET_TID_ADDRESS, (unsigned long) &args->tid_addr, 0, 0, 0);
-	if (ret)
-		return ret;
-
-	args->tid = tid;
-	args->tls = arch_get_tls();
-
-	ret = sys_sigaltstack(NULL, &args->sas);
-
-	return ret;
+	args->tid = sys_gettid();
+	return dump_thread_common(args);
 }
 
 static char proc_mountpoint[] = "proc.crtools";