From: Tejun Heo <tj@kernel.org>
To: akpm@linux-foundation.org
Cc: linux-kernel@vger.kernel.org, rusty@rustcorp.com.au,
bfields@fieldses.org, skinsbursky@parallels.com,
ebiederm@xmission.com, jmorris@namei.org, axboe@kernel.dk,
Tejun Heo <tj@kernel.org>
Subject: [PATCH 03/62] idr: remove _idr_rc_to_errno() hack
Date: Sat, 2 Feb 2013 17:20:04 -0800 [thread overview]
Message-ID: <1359854463-2538-4-git-send-email-tj@kernel.org> (raw)
In-Reply-To: <1359854463-2538-1-git-send-email-tj@kernel.org>
idr uses -1, IDR_NEED_TO_GROW and IDR_NOMORE_SPACE to communicate
exception conditions internally. The return value is later translated
to errno values using _idr_rc_to_errno().
This is confusing. Drop the custom ones and consistently use -EAGAIN
for "tree needs to grow", -ENOMEM for "need more memory" and -ENOSPC
for "ran out of ID space".
Due to the weird memory preloading mechanism, [ra]_get_new*() return
-EAGAIN on memory shortage, so we need to substitute -ENOMEM w/
-EAGAIN on those interface functions. They'll eventually be cleaned
up and the translations will go away.
This patch doesn't introduce any functional changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
---
include/linux/idr.h | 6 ------
lib/idr.c | 35 +++++++++++++++++++++++------------
2 files changed, 23 insertions(+), 18 deletions(-)
diff --git a/include/linux/idr.h b/include/linux/idr.h
index 7c0700c..92e84f7 100644
--- a/include/linux/idr.h
+++ b/include/linux/idr.h
@@ -70,12 +70,6 @@ struct idr {
}
#define DEFINE_IDR(name) struct idr name = IDR_INIT(name)
-/* Actions to be taken after a call to _idr_sub_alloc */
-#define IDR_NEED_TO_GROW -2
-#define IDR_NOMORE_SPACE -3
-
-#define _idr_rc_to_errno(rc) ((rc) == -1 ? -EAGAIN : -ENOSPC)
-
/**
* DOC: idr sync
* idr synchronization (stolen from radix-tree.h)
diff --git a/lib/idr.c b/lib/idr.c
index 282841b..bde6eec 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -133,6 +133,21 @@ int idr_pre_get(struct idr *idp, gfp_t gfp_mask)
}
EXPORT_SYMBOL(idr_pre_get);
+/**
+ * sub_alloc - try to allocate an id without growing the tree depth
+ * @idp: idr handle
+ * @starting_id: id to start search at
+ * @id: pointer to the allocated handle
+ * @pa: idr_layer[MAX_IDR_LEVEL] used as backtrack buffer
+ *
+ * Allocate an id in range [@starting_id, INT_MAX] from @idp without
+ * growing its depth. Returns
+ *
+ * the allocated id >= 0 if successful,
+ * -EAGAIN if the tree needs to grow for allocation to succeed,
+ * -ENOSPC if the id space is exhausted,
+ * -ENOMEM if more idr_layers need to be allocated.
+ */
static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
{
int n, m, sh;
@@ -161,7 +176,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
/* if already at the top layer, we need to grow */
if (id >= 1 << (idp->layers * IDR_BITS)) {
*starting_id = id;
- return IDR_NEED_TO_GROW;
+ return -EAGAIN;
}
p = pa[l];
BUG_ON(!p);
@@ -180,7 +195,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
id = ((id >> sh) ^ n ^ m) << sh;
}
if ((id >= MAX_IDR_BIT) || (id < 0))
- return IDR_NOMORE_SPACE;
+ return -ENOSPC;
if (l == 0)
break;
/*
@@ -189,7 +204,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
if (!p->ary[m]) {
new = get_from_free_list(idp);
if (!new)
- return -1;
+ return -ENOMEM;
new->layer = l-1;
rcu_assign_pointer(p->ary[m], new);
p->count++;
@@ -215,7 +230,7 @@ build_up:
layers = idp->layers;
if (unlikely(!p)) {
if (!(p = get_from_free_list(idp)))
- return -1;
+ return -ENOMEM;
p->layer = 0;
layers = 1;
}
@@ -246,7 +261,7 @@ build_up:
__move_to_free_list(idp, new);
}
spin_unlock_irqrestore(&idp->lock, flags);
- return -1;
+ return -ENOMEM;
}
new->ary[0] = p;
new->count = 1;
@@ -258,7 +273,7 @@ build_up:
rcu_assign_pointer(idp->top, p);
idp->layers = layers;
v = sub_alloc(idp, &id, pa);
- if (v == IDR_NEED_TO_GROW)
+ if (v == -EAGAIN)
goto build_up;
return(v);
}
@@ -306,12 +321,8 @@ int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id)
int rv;
rv = idr_get_new_above_int(idp, ptr, starting_id);
- /*
- * This is a cheap hack until the IDR code can be fixed to
- * return proper error values.
- */
if (rv < 0)
- return _idr_rc_to_errno(rv);
+ return rv == -ENOMEM ? -EAGAIN : rv;
*id = rv;
return 0;
}
@@ -766,7 +777,7 @@ int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
/* get vacant slot */
t = idr_get_empty_slot(&ida->idr, idr_id, pa);
if (t < 0)
- return _idr_rc_to_errno(t);
+ return t == -ENOMEM ? -EAGAIN : t;
if (t * IDA_BITMAP_BITS >= MAX_IDR_BIT)
return -ENOSPC;
--
1.8.1
next prev parent reply other threads:[~2013-02-03 1:21 UTC|newest]
Thread overview: 128+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-03 1:20 [PATCHSET] idr: implement idr_alloc() and convert existing users Tejun Heo
2013-02-03 1:20 ` [PATCH 01/62] idr: cosmetic updates to struct / initializer definitions Tejun Heo
2013-02-03 1:20 ` [PATCH 02/62] idr: relocate idr_for_each_entry() and reorganize id[r|a]_get_new() Tejun Heo
2013-02-03 1:20 ` Tejun Heo [this message]
2013-02-03 1:20 ` [PATCH 04/62] idr: refactor idr_get_new_above() Tejun Heo
2013-02-03 1:20 ` [PATCH 05/62] idr: implement idr_preload[_end]() and idr_alloc() Tejun Heo
2013-02-04 18:32 ` [PATCH v2 " Tejun Heo
2013-02-03 1:20 ` [PATCH 06/62] block: fix synchronization and limit check in blk_alloc_devt() Tejun Heo
2013-02-06 11:00 ` Jens Axboe
2013-02-03 1:20 ` [PATCH 07/62] block: convert to idr_alloc() Tejun Heo
2013-02-04 13:10 ` Jens Axboe
2013-02-03 1:20 ` [PATCH 08/62] block/loop: " Tejun Heo
2013-02-04 13:11 ` Jens Axboe
2013-02-03 1:20 ` [PATCH 09/62] atm/nicstar: " Tejun Heo
2013-02-04 14:04 ` chas williams - CONTRACTOR
2013-02-04 17:06 ` Tejun Heo
2013-02-04 18:06 ` chas williams - CONTRACTOR
2013-02-04 18:37 ` [PATCH v3 " Tejun Heo
2013-02-03 1:20 ` [PATCH 10/62] drbd: " Tejun Heo
2013-02-03 1:20 ` [PATCH 11/62] dca: " Tejun Heo
2013-02-03 1:20 ` [PATCH 12/62] dmaengine: " Tejun Heo
2013-02-03 1:20 ` [PATCH 13/62] firewire: " Tejun Heo
2013-02-03 11:03 ` Stefan Richter
2013-02-03 11:18 ` Stefan Richter
2013-02-04 16:57 ` [PATCH 12.5/62] firewire: add minor number range check to fw_device_init() Tejun Heo
2013-02-04 18:15 ` Stefan Richter
2013-02-04 16:58 ` [PATCH v2 13/62] firewire: convert to idr_alloc() Tejun Heo
2013-02-04 18:16 ` Stefan Richter
2013-02-03 1:20 ` [PATCH 14/62] gpio: " Tejun Heo
2013-02-04 20:40 ` Linus Walleij
2013-02-03 1:20 ` [PATCH 15/62] drm: " Tejun Heo
2013-02-03 1:20 ` [PATCH 16/62] drm/exynos: " Tejun Heo
2013-02-03 1:20 ` [PATCH 17/62] drm/i915: " Tejun Heo
2013-02-04 14:53 ` Daniel Vetter
2013-02-03 1:20 ` [PATCH 18/62] drm/sis: " Tejun Heo
2013-02-03 1:20 ` [PATCH 19/62] drm/via: " Tejun Heo
2013-02-03 1:20 ` [PATCH 20/62] drm/vmwgfx: " Tejun Heo
2013-02-03 1:20 ` [PATCH 21/62] i2c: " Tejun Heo
2013-02-03 1:20 ` [PATCH 22/62] infiniband/core: " Tejun Heo
2013-02-04 16:43 ` [PATCH v2 " Tejun Heo
2013-02-05 0:07 ` Hefty, Sean
2013-02-03 1:20 ` [PATCH 23/62] infiniband/amso1100: " Tejun Heo
2013-02-03 14:36 ` Steve Wise
2013-02-03 1:20 ` [PATCH 24/62] infiniband/cxgb3: " Tejun Heo
2013-02-03 14:37 ` Steve Wise
2013-02-03 1:20 ` [PATCH 25/62] infiniband/cxgb4: " Tejun Heo
2013-02-03 14:18 ` Steve Wise
2013-02-03 14:28 ` Tejun Heo
2013-02-04 15:32 ` Steve Wise
2013-02-03 1:20 ` [PATCH 26/62] infiniband/ehca: " Tejun Heo
2013-02-03 1:20 ` [PATCH 27/62] infiniband/ipath: " Tejun Heo
2013-02-04 16:15 ` Marciniszyn, Mike
2013-02-04 16:18 ` Tejun Heo
2013-02-03 1:20 ` [PATCH 28/62] infiniband/mlx4: " Tejun Heo
2013-02-03 1:20 ` [PATCH 29/62] infiniband/ocrdma: " Tejun Heo
2013-02-03 1:20 ` [PATCH 30/62] infiniband/qib: " Tejun Heo
2013-02-03 1:20 ` [PATCH 31/62] dm: " Tejun Heo
2013-02-03 1:20 ` [PATCH 32/62] memstick: " Tejun Heo
2013-02-03 1:20 ` [PATCH 33/62] mfd: " Tejun Heo
2013-02-03 22:32 ` Samuel Ortiz
2013-02-03 1:20 ` [PATCH 34/62] misc/c2port: " Tejun Heo
2013-02-03 1:20 ` [PATCH 35/62] misc/tifm_core: " Tejun Heo
2013-02-03 1:20 ` [PATCH 36/62] mmc: " Tejun Heo
2013-02-03 1:20 ` [PATCH 37/62] mtd: " Tejun Heo
2013-02-04 13:09 ` Ezequiel Garcia
2013-02-03 1:20 ` [PATCH 38/62] i2c: " Tejun Heo
2013-02-03 1:25 ` [PATCH UPDATED 38/62] macvtap: " Tejun Heo
2013-02-03 1:20 ` [PATCH 39/62] ppp: " Tejun Heo
2013-02-03 1:20 ` [PATCH 40/62] power: " Tejun Heo
2013-02-03 3:46 ` Anton Vorontsov
2013-02-03 1:20 ` [PATCH 41/62] pps: " Tejun Heo
2013-02-03 1:20 ` [PATCH 42/62] remoteproc: " Tejun Heo
2013-02-03 1:20 ` [PATCH 43/62] rpmsg: " Tejun Heo
2013-02-03 1:20 ` [PATCH 44/62] scsi/bfa: " Tejun Heo
2013-02-03 1:20 ` [PATCH 45/62] scsi: " Tejun Heo
2013-02-03 1:20 ` [PATCH 46/62] target/iscsi: " Tejun Heo
2013-02-03 1:20 ` [PATCH 47/62] scsi/lpfc: " Tejun Heo
2013-02-11 22:46 ` James Smart
2013-02-03 1:20 ` [PATCH 48/62] thermal: " Tejun Heo
2013-02-03 1:20 ` [PATCH 49/62] uio: " Tejun Heo
2013-02-03 7:05 ` Greg Kroah-Hartman
2013-02-03 1:20 ` [PATCH 50/62] vfio: " Tejun Heo
2013-02-04 16:06 ` Alex Williamson
2013-02-04 16:48 ` [PATCH v2 " Tejun Heo
2013-02-03 1:20 ` [PATCH 51/62] dlm: " Tejun Heo
2013-02-03 1:20 ` [PATCH 52/62] inotify: " Tejun Heo
2013-02-03 1:20 ` [PATCH 53/62] ocfs2: " Tejun Heo
2013-02-03 1:20 ` [PATCH 54/62] ipc: " Tejun Heo
2013-02-03 1:20 ` [PATCH 55/62] cgroup: " Tejun Heo
2013-02-04 2:49 ` Li Zefan
2013-02-03 1:20 ` [PATCH 56/62] events: " Tejun Heo
2013-02-03 1:20 ` [PATCH 57/62] posix-timers: " Tejun Heo
2013-02-03 1:20 ` [PATCH 58/62] net/9p: " Tejun Heo
2013-02-03 1:21 ` [PATCH 59/62] mac80211: " Tejun Heo
2013-02-04 17:40 ` Johannes Berg
2013-02-04 17:42 ` Tejun Heo
2013-02-03 1:21 ` [PATCH 60/62] sctp: " Tejun Heo
2013-02-03 16:55 ` Neil Horman
2013-02-04 16:22 ` Vlad Yasevich
2013-02-04 16:37 ` Tejun Heo
2013-02-04 16:42 ` [PATCH v2 " Tejun Heo
2013-02-05 15:22 ` Neil Horman
2013-02-03 1:21 ` [PATCH 61/62] nfs4client: " Tejun Heo
2013-02-03 1:21 ` [PATCH 62/62] idr: deprecate idr_pre_get() and idr_get_new[_above]() Tejun Heo
2013-02-03 13:41 ` [PATCHSET] idr: implement idr_alloc() and convert existing users Eric W. Biederman
2013-02-03 14:13 ` Tejun Heo
2013-02-03 15:24 ` Eric W. Biederman
2013-02-03 15:47 ` Tejun Heo
2013-02-03 17:02 ` J. Bruce Fields
2013-02-04 0:15 ` J. Bruce Fields
2013-02-04 17:10 ` Tejun Heo
2013-02-04 17:11 ` Tejun Heo
2013-02-04 18:15 ` J. Bruce Fields
2013-03-21 14:06 ` J. Bruce Fields
2013-03-21 18:35 ` Tejun Heo
2013-03-26 15:19 ` Jeff Layton
2013-03-26 15:26 ` Tejun Heo
2013-03-26 16:30 ` J. Bruce Fields
2013-03-26 16:33 ` Tejun Heo
2013-03-26 16:36 ` Tejun Heo
2013-03-26 16:52 ` Jeff Layton
2013-02-04 17:16 ` J. Bruce Fields
2013-02-04 19:17 ` Tejun Heo
2013-02-04 19:54 ` Marciniszyn, Mike
2013-02-04 21:42 ` Tejun Heo
2013-02-04 22:25 ` Marciniszyn, Mike
2013-02-04 20:08 ` Marciniszyn, Mike
2013-02-04 21:43 ` Tejun Heo
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