From 33166b1ffca5e1945246bcaa77d72a22b0d3e531 Mon Sep 17 00:00:00 2001 From: Richard Kennedy Date: Fri, 25 Jul 2008 01:48:35 -0700 Subject: shrink struct pid by removing padding on 64 bit builds When struct pid is built on a 64 bit platform gcc has to insert padding to maintain the correct alignment, by simply reordering its members the memory usage shrinks from 88 bytes to 80. I've successfully run with this patch on my desktop AMD64 machine. There are no significant kernel size changes to a default config.X86_64 on the latest git v2.6.26-rc1 text data bss dec hex filename 5404828 976760 734280 7115868 6c945c vmlinux 5404811 976760 734280 7115851 6c944b vmlinux.pid-patch Acked-by: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pid.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/pid.h') diff --git a/include/linux/pid.h b/include/linux/pid.h index c21c7e8124a..6f084b9e2c4 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -57,10 +57,10 @@ struct upid { struct pid { atomic_t count; + unsigned int level; /* lists of tasks that use this pid */ struct hlist_head tasks[PIDTYPE_MAX]; struct rcu_head rcu; - unsigned int level; struct upid numbers[1]; }; -- cgit v1.2.3-70-g09d2 From e49859e71e0318b564de1546bdc30fab738f9deb Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Fri, 25 Jul 2008 01:48:36 -0700 Subject: pidns: remove now unused find_pid function. This one had the only users so far - the kill_proc, which is removed, so drop this (invalid in namespaced world) call too. And of course - erase all references on it from comments. Signed-off-by: Pavel Emelyanov Cc: Oleg Nesterov Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pid.h | 4 +--- include/linux/sched.h | 2 +- kernel/pid.c | 8 +------- 3 files changed, 3 insertions(+), 11 deletions(-) (limited to 'include/linux/pid.h') diff --git a/include/linux/pid.h b/include/linux/pid.h index 6f084b9e2c4..ff1b2a5814d 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -48,7 +48,7 @@ enum pid_type */ struct upid { - /* Try to keep pid_chain in the same cacheline as nr for find_pid */ + /* Try to keep pid_chain in the same cacheline as nr for find_vpid */ int nr; struct pid_namespace *ns; struct hlist_node pid_chain; @@ -105,14 +105,12 @@ extern struct pid_namespace init_pid_ns; * or rcu_read_lock() held. * * find_pid_ns() finds the pid in the namespace specified - * find_pid() find the pid by its global id, i.e. in the init namespace * find_vpid() finr the pid by its virtual id, i.e. in the current namespace * * see also find_task_by_pid() set in include/linux/sched.h */ extern struct pid *find_pid_ns(int nr, struct pid_namespace *ns); extern struct pid *find_vpid(int nr); -extern struct pid *find_pid(int nr); /* * Lookup a PID in the hash table, and return with it's count elevated. diff --git a/include/linux/sched.h b/include/linux/sched.h index 134cb5cb506..182da1550fa 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1718,7 +1718,7 @@ extern struct pid_namespace init_pid_ns; * find_task_by_pid(): * finds a task by its global pid * - * see also find_pid() etc in include/linux/pid.h + * see also find_vpid() etc in include/linux/pid.h */ extern struct task_struct *find_task_by_pid_type_ns(int type, int pid, diff --git a/kernel/pid.c b/kernel/pid.c index 753fd90d9ec..064e76afa50 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -309,12 +309,6 @@ struct pid *find_vpid(int nr) } EXPORT_SYMBOL_GPL(find_vpid); -struct pid *find_pid(int nr) -{ - return find_pid_ns(nr, &init_pid_ns); -} -EXPORT_SYMBOL_GPL(find_pid); - /* * attach_pid() must be called with the tasklist_lock write-held. */ @@ -483,7 +477,7 @@ EXPORT_SYMBOL(task_session_nr_ns); /* * Used by proc to find the first pid that is greater then or equal to nr. * - * If there is a pid at nr this function is exactly the same as find_pid. + * If there is a pid at nr this function is exactly the same as find_pid_ns. */ struct pid *find_ge_pid(int nr, struct pid_namespace *ns) { -- cgit v1.2.3-70-g09d2 From dbda0de52618d13d1b927c7ba7bb839cfddc4e8c Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Fri, 25 Jul 2008 01:48:37 -0700 Subject: pidns: remove find_task_by_pid, unused for a long time It seems to me that it was a mistake marking this function as deprecated and scheduling it for removal, rather than resolutely removing it after the last caller's death. Anyway - better late, then never. Signed-off-by: Pavel Emelyanov Cc: Oleg Nesterov Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/feature-removal-schedule.txt | 18 ------------------ include/linux/pid.h | 2 +- include/linux/sched.h | 6 ------ 3 files changed, 1 insertion(+), 25 deletions(-) (limited to 'include/linux/pid.h') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 09c4a1efb8e..721c71b86e0 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -138,24 +138,6 @@ Who: Kay Sievers --------------------------- -What: find_task_by_pid -When: 2.6.26 -Why: With pid namespaces, calling this funciton will return the - wrong task when called from inside a namespace. - - The best way to save a task pid and find a task by this - pid later, is to find this task's struct pid pointer (or get - it directly from the task) and call pid_task() later. - - If someone really needs to get a task by its pid_t, then - he most likely needs the find_task_by_vpid() to get the - task from the same namespace as the current task is in, but - this may be not so in general. - -Who: Pavel Emelyanov - ---------------------------- - What: ACPI procfs interface When: July 2008 Why: ACPI sysfs conversion should be finished by January 2008. diff --git a/include/linux/pid.h b/include/linux/pid.h index ff1b2a5814d..22921ac4cfd 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -107,7 +107,7 @@ extern struct pid_namespace init_pid_ns; * find_pid_ns() finds the pid in the namespace specified * find_vpid() finr the pid by its virtual id, i.e. in the current namespace * - * see also find_task_by_pid() set in include/linux/sched.h + * see also find_task_by_vpid() set in include/linux/sched.h */ extern struct pid *find_pid_ns(int nr, struct pid_namespace *ns); extern struct pid *find_vpid(int nr); diff --git a/include/linux/sched.h b/include/linux/sched.h index 182da1550fa..354ef478a80 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1715,8 +1715,6 @@ extern struct pid_namespace init_pid_ns; * finds a task by its pid in the specified namespace * find_task_by_vpid(): * finds a task by its virtual pid - * find_task_by_pid(): - * finds a task by its global pid * * see also find_vpid() etc in include/linux/pid.h */ @@ -1724,10 +1722,6 @@ extern struct pid_namespace init_pid_ns; extern struct task_struct *find_task_by_pid_type_ns(int type, int pid, struct pid_namespace *ns); -static inline struct task_struct *__deprecated find_task_by_pid(pid_t nr) -{ - return find_task_by_pid_type_ns(PIDTYPE_PID, nr, &init_pid_ns); -} extern struct task_struct *find_task_by_vpid(pid_t nr); extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); -- cgit v1.2.3-70-g09d2