aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMatt Helsley <matthltc@us.ibm.com>2009-06-17 19:27:58 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-18 16:03:56 -0400
commit26c369dada267d3df1beb86cf89b865ac1178a7f (patch)
treef51d2663ffb3155e97b71b38b4e9990fbcf98063
parent665c7741fb63c7ceeb515f1d1ed8b016efe65bf3 (diff)
futex: documentation: fix inconsistent description of futex list_op_pending
Strictly speaking list_op_pending points to the 'lock entry', not the 'lock word' (which is actually at 'offset' from 'lock entry'). We can infer this based on reading the code in kernel/futex.c: struct robust_list __user *entry, *next_entry, *pending; ... if (fetch_robust_entry(&pending, &head->list_op_pending, &pip)) return; ... if (pending) handle_futex_death((void __user *)pending + futex_offset, curr, pip); Which is also consistent with the rest of the docs on robust futex lists. Signed-off-by: Matt Helsley <matthltc@us.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linuxtronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--Documentation/robust-futex-ABI.txt4
1 files changed, 2 insertions, 2 deletions
diff --git a/Documentation/robust-futex-ABI.txt b/Documentation/robust-futex-ABI.txt
index 535f69fab45f..fd1cd8aae4eb 100644
--- a/Documentation/robust-futex-ABI.txt
+++ b/Documentation/robust-futex-ABI.txt
@@ -135,7 +135,7 @@ manipulating this list), the user code must observe the following
135protocol on 'lock entry' insertion and removal: 135protocol on 'lock entry' insertion and removal:
136 136
137On insertion: 137On insertion:
138 1) set the 'list_op_pending' word to the address of the 'lock word' 138 1) set the 'list_op_pending' word to the address of the 'lock entry'
139 to be inserted, 139 to be inserted,
140 2) acquire the futex lock, 140 2) acquire the futex lock,
141 3) add the lock entry, with its thread id (TID) in the bottom 29 bits 141 3) add the lock entry, with its thread id (TID) in the bottom 29 bits
@@ -143,7 +143,7 @@ On insertion:
143 4) clear the 'list_op_pending' word. 143 4) clear the 'list_op_pending' word.
144 144
145On removal: 145On removal:
146 1) set the 'list_op_pending' word to the address of the 'lock word' 146 1) set the 'list_op_pending' word to the address of the 'lock entry'
147 to be removed, 147 to be removed,
148 2) remove the lock entry for this lock from the 'head' list, 148 2) remove the lock entry for this lock from the 'head' list,
149 2) release the futex lock, and 149 2) release the futex lock, and