From 2d70b68d42b5196a48ccb639e3797f097ef5bea3 Mon Sep 17 00:00:00 2001 From: Ken Chen Date: Wed, 20 Aug 2008 14:09:17 -0700 Subject: fix setpriority(PRIO_PGRP) thread iterator breakage When user calls sys_setpriority(PRIO_PGRP ...) on a NPTL style multi-LWP process, only the task leader of the process is affected, all other sibling LWP threads didn't receive the setting. The problem was that the iterator used in sys_setpriority() only iteartes over one task for each process, ignoring all other sibling thread. Introduce a new macro do_each_pid_thread / while_each_pid_thread to walk each thread of a process. Convert 4 call sites in {set/get}priority and ioprio_{set/get}. Signed-off-by: Ken Chen Cc: Oleg Nesterov Cc: Roland McGrath Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ioprio.c | 8 ++++---- include/linux/pid.h | 9 +++++++++ kernel/sys.c | 8 ++++---- 3 files changed, 17 insertions(+), 8 deletions(-) diff --git a/fs/ioprio.c b/fs/ioprio.c index c4a1c3c65aac..da3cc460d4df 100644 --- a/fs/ioprio.c +++ b/fs/ioprio.c @@ -115,11 +115,11 @@ asmlinkage long sys_ioprio_set(int which, int who, int ioprio) pgrp = task_pgrp(current); else pgrp = find_vpid(who); - do_each_pid_task(pgrp, PIDTYPE_PGID, p) { + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { ret = set_task_ioprio(p, ioprio); if (ret) break; - } while_each_pid_task(pgrp, PIDTYPE_PGID, p); + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); break; case IOPRIO_WHO_USER: if (!who) @@ -204,7 +204,7 @@ asmlinkage long sys_ioprio_get(int which, int who) pgrp = task_pgrp(current); else pgrp = find_vpid(who); - do_each_pid_task(pgrp, PIDTYPE_PGID, p) { + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { tmpio = get_task_ioprio(p); if (tmpio < 0) continue; @@ -212,7 +212,7 @@ asmlinkage long sys_ioprio_get(int which, int who) ret = tmpio; else ret = ioprio_best(ret, tmpio); - } while_each_pid_task(pgrp, PIDTYPE_PGID, p); + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); break; case IOPRIO_WHO_USER: if (!who) diff --git a/include/linux/pid.h b/include/linux/pid.h index 22921ac4cfd9..d7e98ff8021e 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -161,4 +161,13 @@ pid_t pid_vnr(struct pid *pid); } \ } while (0) +#define do_each_pid_thread(pid, type, task) \ + do_each_pid_task(pid, type, task) { \ + struct task_struct *tg___ = task; \ + do { + +#define while_each_pid_thread(pid, type, task) \ + } while_each_thread(tg___, task); \ + task = tg___; \ + } while_each_pid_task(pid, type, task) #endif /* _LINUX_PID_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 3dacb00a7f76..038a7bc0901d 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -169,9 +169,9 @@ asmlinkage long sys_setpriority(int which, int who, int niceval) pgrp = find_vpid(who); else pgrp = task_pgrp(current); - do_each_pid_task(pgrp, PIDTYPE_PGID, p) { + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { error = set_one_prio(p, niceval, error); - } while_each_pid_task(pgrp, PIDTYPE_PGID, p); + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); break; case PRIO_USER: user = current->user; @@ -229,11 +229,11 @@ asmlinkage long sys_getpriority(int which, int who) pgrp = find_vpid(who); else pgrp = task_pgrp(current); - do_each_pid_task(pgrp, PIDTYPE_PGID, p) { + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { niceval = 20 - task_nice(p); if (niceval > retval) retval = niceval; - } while_each_pid_task(pgrp, PIDTYPE_PGID, p); + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); break; case PRIO_USER: user = current->user; -- cgit v1.2.3