From ca4ac360af94964906149efe166453ac83ae7c43 Mon Sep 17 00:00:00 2001 From: Dennis Zhou Date: Mon, 4 Feb 2019 15:19:59 -0500 Subject: [PATCH] btrfs: manage heuristic workspace as index 0 While the heuristic workspaces aren't really compression workspaces, they use the same interface for managing them. So rather than branching, let's just handle them once again as the index 0 compression type. Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/compression.c | 112 +++++++++++------------------------------ fs/btrfs/compression.h | 4 ++ 2 files changed, 34 insertions(+), 82 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index d098df768b67..7034cf2749e6 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -769,6 +769,11 @@ fail: return ERR_PTR(-ENOMEM); } +const struct btrfs_compress_op btrfs_heuristic_compress = { + .alloc_workspace = alloc_heuristic_ws, + .free_workspace = free_heuristic_ws, +}; + struct workspace_manager { struct list_head idle_ws; spinlock_t ws_lock; @@ -780,11 +785,11 @@ struct workspace_manager { wait_queue_head_t ws_wait; }; -static struct workspace_manager wsm[BTRFS_COMPRESS_TYPES]; - -static struct workspace_manager btrfs_heuristic_ws; +static struct workspace_manager wsm[BTRFS_NR_WORKSPACE_MANAGERS]; static const struct btrfs_compress_op * const btrfs_compress_op[] = { + /* The heuristic is represented as compression type 0 */ + &btrfs_heuristic_compress, &btrfs_zlib_compress, &btrfs_lzo_compress, &btrfs_zstd_compress, @@ -795,22 +800,7 @@ void __init btrfs_init_compress(void) struct list_head *workspace; int i; - INIT_LIST_HEAD(&btrfs_heuristic_ws.idle_ws); - spin_lock_init(&btrfs_heuristic_ws.ws_lock); - atomic_set(&btrfs_heuristic_ws.total_ws, 0); - init_waitqueue_head(&btrfs_heuristic_ws.ws_wait); - - workspace = alloc_heuristic_ws(); - if (IS_ERR(workspace)) { - pr_warn( - "BTRFS: cannot preallocate heuristic workspace, will try later\n"); - } else { - atomic_set(&btrfs_heuristic_ws.total_ws, 1); - btrfs_heuristic_ws.free_ws = 1; - list_add(workspace, &btrfs_heuristic_ws.idle_ws); - } - - for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) { + for (i = 0; i < BTRFS_NR_WORKSPACE_MANAGERS; i++) { INIT_LIST_HEAD(&wsm[i].idle_ws); spin_lock_init(&wsm[i].ws_lock); atomic_set(&wsm[i].total_ws, 0); @@ -837,11 +827,10 @@ void __init btrfs_init_compress(void) * Preallocation makes a forward progress guarantees and we do not return * errors. */ -static struct list_head *__find_workspace(int type, bool heuristic) +static struct list_head *find_workspace(int type) { struct list_head *workspace; int cpus = num_online_cpus(); - int idx = type - 1; unsigned nofs_flag; struct list_head *idle_ws; spinlock_t *ws_lock; @@ -849,19 +838,11 @@ static struct list_head *__find_workspace(int type, bool heuristic) wait_queue_head_t *ws_wait; int *free_ws; - if (heuristic) { - idle_ws = &btrfs_heuristic_ws.idle_ws; - ws_lock = &btrfs_heuristic_ws.ws_lock; - total_ws = &btrfs_heuristic_ws.total_ws; - ws_wait = &btrfs_heuristic_ws.ws_wait; - free_ws = &btrfs_heuristic_ws.free_ws; - } else { - idle_ws = &wsm[idx].idle_ws; - ws_lock = &wsm[idx].ws_lock; - total_ws = &wsm[idx].total_ws; - ws_wait = &wsm[idx].ws_wait; - free_ws = &wsm[idx].free_ws; - } + idle_ws = &wsm[type].idle_ws; + ws_lock = &wsm[type].ws_lock; + total_ws = &wsm[type].total_ws; + ws_wait = &wsm[type].ws_wait; + free_ws = &wsm[type].free_ws; again: spin_lock(ws_lock); @@ -892,10 +873,7 @@ again: * context of btrfs_compress_bio/btrfs_compress_pages */ nofs_flag = memalloc_nofs_save(); - if (heuristic) - workspace = alloc_heuristic_ws(); - else - workspace = btrfs_compress_op[idx]->alloc_workspace(); + workspace = btrfs_compress_op[type]->alloc_workspace(); memalloc_nofs_restore(nofs_flag); if (IS_ERR(workspace)) { @@ -926,38 +904,23 @@ again: return workspace; } -static struct list_head *find_workspace(int type) -{ - return __find_workspace(type, false); -} - /* * put a workspace struct back on the list or free it if we have enough * idle ones sitting around */ -static void __free_workspace(int type, struct list_head *workspace, - bool heuristic) +static void free_workspace(int type, struct list_head *workspace) { - int idx = type - 1; struct list_head *idle_ws; spinlock_t *ws_lock; atomic_t *total_ws; wait_queue_head_t *ws_wait; int *free_ws; - if (heuristic) { - idle_ws = &btrfs_heuristic_ws.idle_ws; - ws_lock = &btrfs_heuristic_ws.ws_lock; - total_ws = &btrfs_heuristic_ws.total_ws; - ws_wait = &btrfs_heuristic_ws.ws_wait; - free_ws = &btrfs_heuristic_ws.free_ws; - } else { - idle_ws = &wsm[idx].idle_ws; - ws_lock = &wsm[idx].ws_lock; - total_ws = &wsm[idx].total_ws; - ws_wait = &wsm[idx].ws_wait; - free_ws = &wsm[idx].free_ws; - } + idle_ws = &wsm[type].idle_ws; + ws_lock = &wsm[type].ws_lock; + total_ws = &wsm[type].total_ws; + ws_wait = &wsm[type].ws_wait; + free_ws = &wsm[type].free_ws; spin_lock(ws_lock); if (*free_ws <= num_online_cpus()) { @@ -968,20 +931,12 @@ static void __free_workspace(int type, struct list_head *workspace, } spin_unlock(ws_lock); - if (heuristic) - free_heuristic_ws(workspace); - else - btrfs_compress_op[idx]->free_workspace(workspace); + btrfs_compress_op[type]->free_workspace(workspace); atomic_dec(total_ws); wake: cond_wake_up(ws_wait); } -static void free_workspace(int type, struct list_head *ws) -{ - return __free_workspace(type, ws, false); -} - /* * cleanup function for module exit */ @@ -990,14 +945,7 @@ static void free_workspaces(void) struct list_head *workspace; int i; - while (!list_empty(&btrfs_heuristic_ws.idle_ws)) { - workspace = btrfs_heuristic_ws.idle_ws.next; - list_del(workspace); - free_heuristic_ws(workspace); - atomic_dec(&btrfs_heuristic_ws.total_ws); - } - - for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) { + for (i = 0; i < BTRFS_NR_WORKSPACE_MANAGERS; i++) { while (!list_empty(&wsm[i].idle_ws)) { workspace = wsm[i].idle_ws.next; list_del(workspace); @@ -1042,8 +990,8 @@ int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping, workspace = find_workspace(type); - btrfs_compress_op[type - 1]->set_level(workspace, type_level); - ret = btrfs_compress_op[type-1]->compress_pages(workspace, mapping, + btrfs_compress_op[type]->set_level(workspace, type_level); + ret = btrfs_compress_op[type]->compress_pages(workspace, mapping, start, pages, out_pages, total_in, total_out); @@ -1072,7 +1020,7 @@ static int btrfs_decompress_bio(struct compressed_bio *cb) int type = cb->compress_type; workspace = find_workspace(type); - ret = btrfs_compress_op[type - 1]->decompress_bio(workspace, cb); + ret = btrfs_compress_op[type]->decompress_bio(workspace, cb); free_workspace(type, workspace); return ret; @@ -1091,7 +1039,7 @@ int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page, workspace = find_workspace(type); - ret = btrfs_compress_op[type-1]->decompress(workspace, data_in, + ret = btrfs_compress_op[type]->decompress(workspace, data_in, dest_page, start_byte, srclen, destlen); @@ -1512,7 +1460,7 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, */ int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end) { - struct list_head *ws_list = __find_workspace(0, true); + struct list_head *ws_list = find_workspace(0); struct heuristic_ws *ws; u32 i; u8 byte; @@ -1581,7 +1529,7 @@ int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end) } out: - __free_workspace(0, ws_list, true); + free_workspace(0, ws_list); return ret; } diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h index 004db0b3111b..9a0e73c65b87 100644 --- a/fs/btrfs/compression.h +++ b/fs/btrfs/compression.h @@ -132,6 +132,10 @@ struct btrfs_compress_op { void (*set_level)(struct list_head *ws, unsigned int type); }; +/* The heuristic workspaces are managed via the 0th workspace manager */ +#define BTRFS_NR_WORKSPACE_MANAGERS (BTRFS_COMPRESS_TYPES + 1) + +extern const struct btrfs_compress_op btrfs_heuristic_compress; extern const struct btrfs_compress_op btrfs_zlib_compress; extern const struct btrfs_compress_op btrfs_lzo_compress; extern const struct btrfs_compress_op btrfs_zstd_compress;