Skip site navigation (1)Skip section navigation (2) 
Date:      Fri, 24 Jul 2020 23:44:36 +0000 (UTC)
From:      Mateusz Guzik <mjg@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org
Subject:   svn commit: r363500 - stable/12/sys/amd64/amd64
Message-ID:  <202007242344.06ONiaEd028114@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help 
Author: mjg
Date: Fri Jul 24 23:44:35 2020
New Revision: 363500
URL: https://svnweb.freebsd.org/changeset/base/363500

Log:
  MFC r352874:
  
      amd64 pmap: batch chunk removal in pmap_remove_pages

Modified:
  stable/12/sys/amd64/amd64/pmap.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/amd64/amd64/pmap.c
==============================================================================
--- stable/12/sys/amd64/amd64/pmap.c	Fri Jul 24 23:17:09 2020	(r363499)
+++ stable/12/sys/amd64/amd64/pmap.c	Fri Jul 24 23:44:35 2020	(r363500)
@@ -1111,7 +1111,10 @@ static caddr_t crashdumpmap;
 #define	MAPDEV_SETATTR		0x00000002	/* Modify existing attrs. */
 #define	MAPDEV_ASSERTVALID	0x00000004	/* Assert mapping validity. */
 
+TAILQ_HEAD(pv_chunklist, pv_chunk);
+
 static void	free_pv_chunk(struct pv_chunk *pc);
+static void	free_pv_chunk_batch(struct pv_chunklist *batch);
 static void	free_pv_entry(pmap_t pmap, pv_entry_t pv);
 static pv_entry_t get_pv_entry(pmap_t pmap, struct rwlock **lockp);
 static int	popcnt_pc_map_pq(uint64_t *map);
@@ -4313,13 +4316,10 @@ free_pv_entry(pmap_t pmap, pv_entry_t pv)
 }
 
 static void
-free_pv_chunk(struct pv_chunk *pc)
+free_pv_chunk_dequeued(struct pv_chunk *pc)
 {
 	vm_page_t m;
 
-	mtx_lock(&pv_chunks_mutex);
- 	TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
-	mtx_unlock(&pv_chunks_mutex);
 	PV_STAT(atomic_subtract_int(&pv_entry_spare, _NPCPV));
 	PV_STAT(atomic_subtract_int(&pc_chunk_count, 1));
 	PV_STAT(atomic_add_int(&pc_chunk_frees, 1));
@@ -4330,6 +4330,35 @@ free_pv_chunk(struct pv_chunk *pc)
 	vm_page_free(m);
 }
 
+static void
+free_pv_chunk(struct pv_chunk *pc)
+{
+
+	mtx_lock(&pv_chunks_mutex);
+	TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
+	mtx_unlock(&pv_chunks_mutex);
+	free_pv_chunk_dequeued(pc);
+}
+
+static void
+free_pv_chunk_batch(struct pv_chunklist *batch)
+{
+	struct pv_chunk *pc, *npc;
+
+	if (TAILQ_EMPTY(batch))
+		return;
+
+	mtx_lock(&pv_chunks_mutex);
+	TAILQ_FOREACH(pc, batch, pc_list) {
+		TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
+	}
+	mtx_unlock(&pv_chunks_mutex);
+
+	TAILQ_FOREACH_SAFE(pc, batch, pc_list, npc) {
+		free_pv_chunk_dequeued(pc);
+	}
+}
+
 /*
  * Returns a new PV entry, allocating a new PV chunk from the system when
  * needed.  If this PV chunk allocation fails and a PV list lock pointer was
@@ -6946,6 +6975,7 @@ pmap_remove_pages(pmap_t pmap)
 	pt_entry_t *pte, tpte;
 	pt_entry_t PG_M, PG_RW, PG_V;
 	struct spglist free;
+	struct pv_chunklist free_chunks;
 	vm_page_t m, mpte, mt;
 	pv_entry_t pv;
 	struct md_page *pvh;
@@ -6981,6 +7011,7 @@ pmap_remove_pages(pmap_t pmap)
 	PG_V = pmap_valid_bit(pmap);
 	PG_RW = pmap_rw_bit(pmap);
 
+	TAILQ_INIT(&free_chunks);
 	SLIST_INIT(&free);
 	PMAP_LOCK(pmap);
 	TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
@@ -7108,13 +7139,14 @@ pmap_remove_pages(pmap_t pmap)
 		PV_STAT(atomic_subtract_long(&pv_entry_count, freed));
 		if (allfree) {
 			TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
-			free_pv_chunk(pc);
+			TAILQ_INSERT_TAIL(&free_chunks, pc, pc_list);
 		}
 	}
 	if (lock != NULL)
 		rw_wunlock(lock);
 	pmap_invalidate_all(pmap);
 	pmap_pkru_deassign_all(pmap);
+	free_pv_chunk_batch(&free_chunks);
 	PMAP_UNLOCK(pmap);
 	vm_page_free_pages_toq(&free, true);
 }

Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202007242344.06ONiaEd028114>