LU-16893 libcfs: Remove force_sig usage from lfsck

The lfsck pool of kernel threads uses force_sig() to signal
the worker threads to stop. A signal is used here as the
lfsck workers may be waiting in various, and possibly
nested, states.

As force_sig() has been removed let us simply enable SIGINT
to be passed to the worker threads using send_sig().

Test-parameters: testlist=sanity-lfsck,lfsck-performance
HPE-bug-id: LUS-11670
Fixes: db9f9543ec ("LU-12634 libcfs: force_sig() removed task parameter")
Signed-off-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Change-Id: Ibf6a67f43687960b3eff9cb9a7c7dc8b1be1da63
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/51470
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Neil Brown <neilb@suse.de>

diff --git a/libcfs/autoconf/lustre-libcfs.m4 b/libcfs/autoconf/lustre-libcfs.m4
index 5c201e0..5f82b37 100644 (file)
--- a/libcfs/autoconf/lustre-libcfs.m4
+++ b/libcfs/autoconf/lustre-libcfs.m4
@@ -1782,27 +1782,6 @@ AC_DEFUN([LIBCFS_LOOKUP_USER_KEY], [
 ]) # LIBCFS_LOOKUP_USER_KEY
 
 #
-# LIBCFS_FORCE_SIG_WITH_TASK
-#
-# kernel 5.3 commit 3cf5d076fb4d48979f382bc9452765bf8b79e740
-# signal: Remove task parameter from force_sig
-#
-AC_DEFUN([LIBCFS_SRC_FORCE_SIG_WITH_TASK], [
-       LB2_LINUX_TEST_SRC([force_sig_with_task], [
-               #include <linux/sched/signal.h>
-       ],[
-               force_sig(SIGINT, NULL);
-       ],[-Werror])
-])
-AC_DEFUN([LIBCFS_FORCE_SIG_WITH_TASK], [
-       AC_MSG_CHECKING([if force_sig has task parameter])
-       LB2_LINUX_TEST_RESULT([force_sig_with_task], [
-               AC_DEFINE(HAVE_FORCE_SIG_WITH_TASK, 1,
-                       [force_sig() has task parameter])
-       ])
-]) # LIBCFS_FORCE_SIG_WITH_TASK
-
-#
 # LIBCFS_CACHE_DETAIL_WRITERS
 #
 # kernel v5.3-rc2-1-g64a38e840ce5
@@ -2442,7 +2421,6 @@ AC_DEFUN([LIBCFS_PROG_LINUX_SRC], [
        LIBCFS_SRC_KOBJ_TYPE_DEFAULT_GROUPS
        # 5.3
        LIBCFS_SRC_LOOKUP_USER_KEY
-       LIBCFS_SRC_FORCE_SIG_WITH_TASK
        LIBCFS_SRC_CACHE_DETAIL_WRITERS
        # 5.4
        LIBCFS_SRC_GENL_DUMPIT_INFO
@@ -2587,7 +2565,6 @@ AC_DEFUN([LIBCFS_PROG_LINUX_RESULTS], [
        LIBCFS_KOBJ_TYPE_DEFAULT_GROUPS
        # 5.3
        LIBCFS_LOOKUP_USER_KEY
-       LIBCFS_FORCE_SIG_WITH_TASK
        LIBCFS_CACHE_DETAIL_WRITERS
        # 5.4
        LIBCFS_GENL_DUMPIT_INFO

diff --git a/libcfs/include/libcfs/linux/linux-misc.h b/libcfs/include/libcfs/linux/linux-misc.h
index 2f3b305..e00f79d 100644 (file)
--- a/libcfs/include/libcfs/linux/linux-misc.h
+++ b/libcfs/include/libcfs/linux/linux-misc.h
@@ -119,20 +119,6 @@ static inline int kref_read(const struct kref *kref)
 }
 #endif /* HAVE_KREF_READ */
 
-#ifdef HAVE_FORCE_SIG_WITH_TASK
-#define cfs_force_sig(sig, task)       force_sig((sig), (task))
-#else
-#define cfs_force_sig(sig, task)                                       \
-do {                                                                   \
-       unsigned long flags;                                            \
-                                                                       \
-       spin_lock_irqsave(&task->sighand->siglock, flags);              \
-       task->sighand->action[sig - 1].sa.sa_handler = SIG_DFL;         \
-       send_sig(sig, task, 1);                                         \
-       spin_unlock_irqrestore(&task->sighand->siglock, flags);         \
-} while (0)
-#endif
-
 void cfs_arch_init(void);
 
 #ifndef container_of_safe

diff --git a/lustre/lfsck/lfsck_engine.c b/lustre/lfsck/lfsck_engine.c
index 19564d6..969000a 100644 (file)
--- a/lustre/lfsck/lfsck_engine.c
+++ b/lustre/lfsck/lfsck_engine.c
@@ -1016,6 +1016,11 @@ int lfsck_master_engine(void *args)
        int                       rc;
        ENTRY;
 
+       /*
+        * thread is spawned with all signals set to SIG_IGN, re-enable
+        * SIGINT for lfsck_stop() to awaken and stop the thread.
+        */
+       allow_signal(SIGINT);
        spin_lock(&lfsck->li_lock);
        lfsck->li_task = current;
        spin_unlock(&lfsck->li_lock);
@@ -1597,6 +1602,11 @@ int lfsck_assistant_engine(void *args)
                GOTO(fini, rc);
        }
 
+       /*
+        * thread is spawned with all signals set to SIG_IGN, re-enable
+        * SIGINT for lfsck_stop() to awaken and stop the thread.
+        */
+       allow_signal(SIGINT);
        spin_lock(&lad->lad_lock);
        lad->lad_task = current;
        thread_set_flags(athread, SVC_RUNNING);

diff --git a/lustre/lfsck/lfsck_lib.c b/lustre/lfsck/lfsck_lib.c
index bb69561..8703cb0 100644 (file)
--- a/lustre/lfsck/lfsck_lib.c
+++ b/lustre/lfsck/lfsck_lib.c
@@ -3403,8 +3403,8 @@ int lfsck_stop(const struct lu_env *env, struct dt_device *key,
 
        thread_set_flags(thread, SVC_STOPPING);
 
-       LASSERT(lfsck->li_task != NULL);
-       cfs_force_sig(SIGINT, lfsck->li_task);
+       LASSERT(lfsck->li_task);
+       send_sig(SIGINT, lfsck->li_task, 1);
 
        if (lfsck->li_master) {
                struct lfsck_component *com;
@@ -3413,16 +3413,16 @@ int lfsck_stop(const struct lu_env *env, struct dt_device *key,
                list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
                        lad = com->lc_data;
                        spin_lock(&lad->lad_lock);
-                       if (lad->lad_task != NULL)
-                               cfs_force_sig(SIGINT, lad->lad_task);
+                       if (lad->lad_task)
+                               send_sig(SIGINT, lad->lad_task, 1);
                        spin_unlock(&lad->lad_lock);
                }
 
                list_for_each_entry(com, &lfsck->li_list_double_scan, lc_link) {
                        lad = com->lc_data;
                        spin_lock(&lad->lad_lock);
-                       if (lad->lad_task != NULL)
-                               cfs_force_sig(SIGINT, lad->lad_task);
+                       if (lad->lad_task)
+                               send_sig(SIGINT, lad->lad_task, 1);
                        spin_unlock(&lad->lad_lock);
                }
        }