Change 663745 by justing@justing_ns1_spectrabsd_integration on 2013/04/05 17:55:49
	Large sector device support.
	
	Calculate the minimum blocksize of each metaslab class.  Use
	the calculated value instead of SPA_MINBLOCKSIZE (512b) when
	determining the likelyhood of compression yeilding a reduction
	in physical space usage.
	
	sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c:
	sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/metaslab_impl.h:
		When the group membership of a metaslab class changes
		(i.e. when a vdev is added or removed from a pool),
		walk the group list to determine the smallest block
		size currently available and record this in the
		metaslab class.
	
	sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/metaslab.h:
	sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c:
		Add the metaslab_class_get_minblocksize() accessor.
	
	sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zio_compress.h:
	sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio_compress.c:
		In zio_compress_data(), take the minimum blocksize as
		an input parameter instead of assuming SPA_MINBLOCKSIZE.
	
	sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c:
		In zio_write_bp_init(), use the minimum blocksize of the
		normal metaslab class when compressing data.

Affected files ...

... //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c#4 edit
... //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/metaslab.h#2 edit
... //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/metaslab_impl.h#3 edit
... //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zio_compress.h#4 edit
... //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c#6 edit
... //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio_compress.c#4 edit

Differences ...

==== //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c#4 (text) ====

@@ -165,6 +165,27 @@
 	atomic_add_64(&mc->mc_dspace, dspace_delta);
 }
 
+void
+metaslab_class_minblocksize_update(metaslab_class_t *mc)
+{
+	metaslab_group_t *mg;
+	vdev_t *vd;
+	uint64_t minashift = UINT64_MAX;
+
+	if ((mg = mc->mc_rotor) == NULL) {
+		mc->mc_minblocksize = SPA_MINBLOCKSIZE;
+		return;
+	}
+
+	do {
+		vd = mg->mg_vd;
+		if (vd->vdev_ashift < minashift)
+			minashift = vd->vdev_ashift;
+	} while ((mg = mg->mg_next) != mc->mc_rotor);
+
+	mc->mc_minblocksize = 1ULL << minashift;
+}
+
 uint64_t
 metaslab_class_get_alloc(metaslab_class_t *mc)
 {
@@ -189,6 +210,12 @@
 	return (spa_deflate(mc->mc_spa) ? mc->mc_dspace : mc->mc_space);
 }
 
+uint64_t
+metaslab_class_get_minblocksize(metaslab_class_t *mc)
+{
+	return (mc->mc_minblocksize);
+}
+
 /*
  * ==========================================================================
  * Metaslab groups
@@ -280,6 +307,7 @@
 		mgnext->mg_prev = mg;
 	}
 	mc->mc_rotor = mg;
+	metaslab_class_minblocksize_update(mc);
 }
 
 void
@@ -311,6 +339,7 @@
 
 	mg->mg_prev = NULL;
 	mg->mg_next = NULL;
+	metaslab_class_minblocksize_update(mc);
 }
 
 static void

==== //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/metaslab.h#2 (text) ====

@@ -69,6 +69,7 @@
 extern uint64_t metaslab_class_get_space(metaslab_class_t *mc);
 extern uint64_t metaslab_class_get_dspace(metaslab_class_t *mc);
 extern uint64_t metaslab_class_get_deferred(metaslab_class_t *mc);
+extern uint64_t metaslab_class_get_minblocksize(metaslab_class_t *mc);
 
 extern metaslab_group_t *metaslab_group_create(metaslab_class_t *mc,
     vdev_t *vd);

==== //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/metaslab_impl.h#3 (text) ====

@@ -49,6 +49,7 @@
 	uint64_t		mc_deferred;	/**< total deferred frees */
 	uint64_t		mc_space;	/**< total space (alloc + free) */
 	uint64_t		mc_dspace;	/**< total deflated space */
+	uint64_t		mc_minblocksize;
 };
 
 struct metaslab_group {

==== //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zio_compress.h#4 (text) ====

@@ -76,7 +76,7 @@
  * Compress and decompress data if necessary.
  */
 extern size_t zio_compress_data(enum zio_compress c, void *src, void *dst,
-    size_t s_len);
+    size_t s_len, size_t minblocksize);
 extern int zio_decompress_data(enum zio_compress c, void *src, void *dst,
     size_t s_len, size_t d_len);
 

==== //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c#6 (text) ====

@@ -1062,8 +1062,10 @@
 	}
 
 	if (compress != ZIO_COMPRESS_OFF) {
+		metaslab_class_t *mc = spa_normal_class(spa);
 		void *cbuf = zio_buf_alloc(lsize);
-		psize = zio_compress_data(compress, zio->io_data, cbuf, lsize);
+		psize = zio_compress_data(compress, zio->io_data, cbuf, lsize,
+		    (size_t)metaslab_class_get_minblocksize(mc));
 		if (psize == 0 || psize == lsize) {
 			compress = ZIO_COMPRESS_OFF;
 			zio_buf_free(cbuf, lsize);

==== //SpectraBSD/stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio_compress.c#4 (text) ====

@@ -91,7 +91,8 @@
 }
 
 size_t
-zio_compress_data(enum zio_compress c, void *src, void *dst, size_t s_len)
+zio_compress_data(enum zio_compress c, void *src, void *dst, size_t s_len,
+    size_t minblocksize)
 {
 	uint64_t *word, *word_end;
 	size_t c_len, d_len, r_len;
@@ -120,7 +121,7 @@
 		return (s_len);
 
 	/* Compress at least 12.5% */
-	d_len = P2ALIGN(s_len - (s_len >> 3), (size_t)SPA_MINBLOCKSIZE);
+ 	d_len = P2ALIGN(s_len - (s_len >> 3), minblocksize);
 	if (d_len == 0) {
 		ZCOMPSTAT_BUMP(zcompstat_skipped_minblocksize);
 		return (s_len);
@@ -137,14 +138,14 @@
 	 * Cool.  We compressed at least as much as we were hoping to.
 	 * For both security and repeatability, pad out the last sector.
 	 */
-	r_len = P2ROUNDUP(c_len, (size_t)SPA_MINBLOCKSIZE);
+	r_len = P2ROUNDUP(c_len, minblocksize);
 	if (r_len > c_len) {
 		bzero((char *)dst + c_len, r_len - c_len);
 		c_len = r_len;
 	}
 
 	ASSERT3U(c_len, <=, d_len);
-	ASSERT(P2PHASE(c_len, (size_t)SPA_MINBLOCKSIZE) == 0);
+	ASSERT(P2PHASE(c_len, minblocksize) == 0);
 
 	return (c_len);
 }