The branch stable/13 has been updated by mjg:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=a6a4a57ca3e8fe5ca539c31cb1fab7acf8a26dd7

commit a6a4a57ca3e8fe5ca539c31cb1fab7acf8a26dd7
Author:     Mateusz Guzik <[email protected]>
AuthorDate: 2023-10-12 06:47:45 +0000
Commit:     Mateusz Guzik <[email protected]>
CommitDate: 2023-10-13 23:52:39 +0000

    vfs: count recycles by vnlru and by vn_alloc separately
    
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    
    (cherry picked from commit a92fc3122d2becfbf5a627af6eda5cedfac57c31)
---
 sys/kern/vfs_subr.c | 52 ++++++++++++++++++++++++++++++++++++----------------
 1 file changed, 36 insertions(+), 16 deletions(-)

diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 2be83da5d73f..530afbe05b3e 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -109,7 +109,7 @@ static void delmntque(struct vnode *vp);
 static int     flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo,
                    int slpflag, int slptimeo);
 static void    syncer_shutdown(void *arg, int howto);
-static int     vtryrecycle(struct vnode *vp);
+static int     vtryrecycle(struct vnode *vp, bool isvnlru);
 static void    v_init_counters(struct vnode *);
 static void    vn_seqc_init(struct vnode *);
 static void    vn_seqc_write_end_free(struct vnode *vp);
@@ -210,6 +210,11 @@ SYSCTL_COUNTER_U64(_vfs, OID_AUTO, recycles_free, 
CTLFLAG_RD, &recycles_free_cou
 SYSCTL_COUNTER_U64(_vfs_vnode_vnlru, OID_AUTO, recycles_free, CTLFLAG_RD, 
&recycles_free_count,
     "Number of free vnodes recycled to meet vnode cache targets");
 
+static counter_u64_t direct_recycles_free_count;
+SYSCTL_COUNTER_U64(_vfs_vnode_vnlru, OID_AUTO, direct_recycles_free, 
CTLFLAG_RD,
+    &direct_recycles_free_count,
+    "Number of free vnodes recycled by vn_alloc callers to meet vnode cache 
targets");
+
 static counter_u64_t vnode_skipped_requeues;
 SYSCTL_COUNTER_U64(_vfs_vnode_stats, OID_AUTO, skipped_requeues, CTLFLAG_RD, 
&vnode_skipped_requeues,
     "Number of times LRU requeue was skipped due to lock contention");
@@ -765,6 +770,7 @@ vntblinit(void *dummy __unused)
        vnodes_created = counter_u64_alloc(M_WAITOK);
        recycles_count = counter_u64_alloc(M_WAITOK);
        recycles_free_count = counter_u64_alloc(M_WAITOK);
+       direct_recycles_free_count = counter_u64_alloc(M_WAITOK);
        vnode_skipped_requeues = counter_u64_alloc(M_WAITOK);
 
        /*
@@ -1307,7 +1313,7 @@ SYSCTL_INT(_vfs_vnode_vnlru, OID_AUTO, max_free_per_call, 
CTLFLAG_RW,
  * Attempt to reduce the free list by the requested amount.
  */
 static int
-vnlru_free_impl(int count, struct vfsops *mnt_op, struct vnode *mvp)
+vnlru_free_impl(int count, struct vfsops *mnt_op, struct vnode *mvp, bool 
isvnlru)
 {
        struct vnode *vp;
        struct mount *mp;
@@ -1393,7 +1399,7 @@ vnlru_free_impl(int count, struct vfsops *mnt_op, struct 
vnode *mvp)
                 *
                 * Check nullfs for one example (null_getwritemount).
                 */
-               vtryrecycle(vp);
+               vtryrecycle(vp, isvnlru);
                count--;
                if (count == 0) {
                        break;
@@ -1409,22 +1415,33 @@ vnlru_free_impl(int count, struct vfsops *mnt_op, 
struct vnode *mvp)
  * XXX: returns without vnode_list_mtx locked!
  */
 static int
-vnlru_free_locked(int count)
+vnlru_free_locked_direct(int count)
 {
        int ret;
 
        mtx_assert(&vnode_list_mtx, MA_OWNED);
-       ret = vnlru_free_impl(count, NULL, vnode_list_free_marker);
+       ret = vnlru_free_impl(count, NULL, vnode_list_free_marker, false);
        mtx_assert(&vnode_list_mtx, MA_NOTOWNED);
        return (ret);
 }
 
 static int
-vnlru_free(int count)
+vnlru_free_locked_vnlru(int count)
+{
+       int ret;
+
+       mtx_assert(&vnode_list_mtx, MA_OWNED);
+       ret = vnlru_free_impl(count, NULL, vnode_list_free_marker, true);
+       mtx_assert(&vnode_list_mtx, MA_NOTOWNED);
+       return (ret);
+}
+
+static int
+vnlru_free_vnlru(int count)
 {
 
        mtx_lock(&vnode_list_mtx);
-       return (vnlru_free_locked(count));
+       return (vnlru_free_locked_vnlru(count));
 }
 
 void
@@ -1435,7 +1452,7 @@ vnlru_free_vfsops(int count, struct vfsops *mnt_op, 
struct vnode *mvp)
        MPASS(mvp != NULL);
        VNPASS(mvp->v_type == VMARKER, mvp);
        mtx_lock(&vnode_list_mtx);
-       vnlru_free_impl(count, mnt_op, mvp);
+       vnlru_free_impl(count, mnt_op, mvp, true);
        mtx_assert(&vnode_list_mtx, MA_NOTOWNED);
 }
 
@@ -1451,7 +1468,7 @@ vnlru_free(int count, struct vfsops *mnt_op)
                return;
        mtx_lock(&vnode_list_mtx);
        mvp = vnode_list_free_marker;
-       if (vnlru_free_impl(count, mnt_op, mvp) == 0) {
+       if (vnlru_free_impl(count, mnt_op, mvp, true) == 0) {
                /*
                 * It is possible the marker was moved over eligible vnodes by
                 * callers which filtered by different ops. If so, start from
@@ -1461,7 +1478,7 @@ vnlru_free(int count, struct vfsops *mnt_op)
                        TAILQ_REMOVE(&vnode_list, mvp, v_vnodelist);
                        TAILQ_INSERT_HEAD(&vnode_list, mvp, v_vnodelist);
                }
-               vnlru_free_impl(count, mnt_op, mvp);
+               vnlru_free_impl(count, mnt_op, mvp, true);
        }
        mtx_unlock(&vnode_list_mtx);
 }
@@ -1719,7 +1736,7 @@ vnlru_proc_light(void)
                return (false);
 
        if (freecount != 0) {
-               vnlru_free(freecount);
+               vnlru_free_vnlru(freecount);
        }
 
        mtx_lock(&vnode_list_mtx);
@@ -1765,7 +1782,7 @@ vnlru_proc(void)
                 * try to reduce it by discarding from the free list.
                 */
                if (rnumvnodes > desiredvnodes + 10) {
-                       vnlru_free_locked(rnumvnodes - desiredvnodes);
+                       vnlru_free_locked_vnlru(rnumvnodes - desiredvnodes);
                        mtx_lock(&vnode_list_mtx);
                        rnumvnodes = atomic_load_long(&numvnodes);
                }
@@ -1865,7 +1882,7 @@ SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, 
kproc_start,
  * through vgone().
  */
 static int
-vtryrecycle(struct vnode *vp)
+vtryrecycle(struct vnode *vp, bool isvnlru)
 {
        struct mount *vnmp;
 
@@ -1911,7 +1928,10 @@ vtryrecycle(struct vnode *vp)
                return (EBUSY);
        }
        if (!VN_IS_DOOMED(vp)) {
-               counter_u64_add(recycles_free_count, 1);
+               if (isvnlru)
+                       counter_u64_add(recycles_free_count, 1);
+               else
+                       counter_u64_add(direct_recycles_free_count, 1);
                vgonel(vp);
        }
        VOP_UNLOCK(vp);
@@ -1984,7 +2004,7 @@ vn_alloc_hard(struct mount *mp, u_long rnumvnodes, bool 
bumped)
         * should be chosen so that we never wait or even reclaim from
         * the free list to below its target minimum.
         */
-       if (vnlru_free_locked(1) > 0)
+       if (vnlru_free_locked_direct(1) > 0)
                goto alloc;
        mtx_assert(&vnode_list_mtx, MA_NOTOWNED);
        if (mp == NULL || (mp->mnt_kern_flag & MNTK_SUSPEND) == 0) {
@@ -2001,7 +2021,7 @@ vn_alloc_hard(struct mount *mp, u_long rnumvnodes, bool 
bumped)
                msleep(&vnlruproc_sig, &vnode_list_mtx, PVFS, "vlruwk", hz);
                if (atomic_load_long(&numvnodes) + 1 > desiredvnodes &&
                    vnlru_read_freevnodes() > 1)
-                       vnlru_free_locked(1);
+                       vnlru_free_locked_direct(1);
                else
                        mtx_unlock(&vnode_list_mtx);
        }

Reply via email to