DLPX-78776 estat zpl may warn about missing more events than were observed

Author: brad-lewis

bpf/estat/zpl.c

@@ -22,49 +22,19 @@ typedef struct {
 // Map of thread id to info about an in-progress IO
 BPF_HASH(io_info_map, u32, io_info_t);
 
-#ifndef OPTARG
-#define	POOL "domain0"
-#else
-#define	POOL (OPTARG)
-#endif
 #define ZFS_READ_SYNC_LENGTH 14
 #define ZFS_READ_ASYNC_LENGTH 15
 #define ZFS_WRITE_SYNC_LENGTH 15
 #define ZFS_WRITE_ASYNC_LENGTH 16
 
-// TODO factor this out into a helper so that it isn't duplicated
-static inline bool
-equal_to_pool(char *str)
-{
-	char comparand[sizeof (POOL)];
-	bpf_probe_read(&comparand, sizeof (comparand), str);
-	char compare[] = POOL;
-	for (int i = 0; i < sizeof (comparand); ++i)
-		if (compare[i] != comparand[i])
-			return (false);
-	return (true);
-}
-
 static inline int
 zfs_read_write_entry(io_info_t *info, struct znode *zn, zfs_uio_t *uio, int flags)
 {
-	// Essentially ITOZSB, but written explicitly so that BCC can insert
-	// the necessary calls to bpf_probe_read.
-	zfsvfs_t *zfsvfs = zn->z_inode.i_sb->s_fs_info;
-
-	objset_t *z_os = zfsvfs->z_os;
-	spa_t *spa = z_os->os_spa;
-
-	if (!equal_to_pool(spa->spa_name))
-		return (0);
-
 	info->start_time = bpf_ktime_get_ns();
 	info->bytes = uio->uio_resid;
-	info->is_sync =
-	    z_os->os_sync == ZFS_SYNC_ALWAYS || (flags & (O_SYNC | O_DSYNC));
+	info->is_sync = (flags & (O_SYNC | O_DSYNC));
 
 	u32 tid = bpf_get_current_pid_tgid();
-	io_info_t *infop = io_info_map.lookup(&tid);
 	io_info_map.update(&tid, info);
 
 	return (0);
@@ -91,7 +61,7 @@ zfs_write_entry(struct pt_regs *ctx, struct znode *zn, zfs_uio_t *uio, int flags
 // @@ kretprobe|zfs_read|zfs_read_write_exit
 // @@ kretprobe|zfs_write|zfs_read_write_exit
 int
-zfs_read_write_exit(struct pt_regs *ctx, struct znode *zn, zfs_uio_t *uio)
+zfs_read_write_exit(struct pt_regs *ctx)
 {
 	u32 tid = bpf_get_current_pid_tgid();
 	io_info_t *info = io_info_map.lookup(&tid);
@@ -110,11 +80,7 @@ zfs_read_write_exit(struct pt_regs *ctx, struct znode *zn, zfs_uio_t *uio)
 			__builtin_memcpy(name, "zfs_write async", ZFS_WRITE_ASYNC_LENGTH);
 		}
 	} else {
-		if (info->is_sync) {
-			__builtin_memcpy(name, "zfs_read sync", ZFS_READ_SYNC_LENGTH);
-		} else {
-			__builtin_memcpy(name, "zfs_read async", ZFS_READ_ASYNC_LENGTH);
-		}
+		__builtin_memcpy(name, "zfs_read", ZFS_READ_SYNC_LENGTH);
 	}
 
 	char axis = 0;