On Fri, May 10, 2002 at 06:17:07AM -0700, William Lee Irwin III wrote:
> d'oh!!!
Batched messages from the "How the heck did I screw this up?" department...
Converting pidhash to list_t, take 3.
Cheers,
Bill
# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
# This patch includes the following deltas:
# ChangeSet 1.530 -> 1.534
# kernel/ksyms.c 1.83 -> 1.84
# kernel/fork.c 1.43 -> 1.44
# include/linux/sched.h 1.55 -> 1.56
# kernel/sched.c 1.73 -> 1.77
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 02/05/09 wli@holomorphy.com 1.531
# Cleanup of pidhash to use list_t for list linkage.
# --------------------------------------------
# 02/05/10 wli@holomorphy.com 1.532
# Actually bootmem alloc the pidhash table.
# --------------------------------------------
# 02/05/10 wli@holomorphy.com 1.533
# sched.c:
# Include bootmem.h
# --------------------------------------------
# 02/05/10 wli@holomorphy.com 1.534
# sched.c:
# Initialize pidhash_size before using it.
# --------------------------------------------
#
diff -Nru a/include/linux/sched.h b/include/linux/sched.h
--- a/include/linux/sched.h Fri May 10 14:40:47 2002
+++ b/include/linux/sched.h Fri May 10 14:40:47 2002
@@ -283,8 +283,7 @@
struct list_head thread_group;
/* PID hash table linkage. */
- struct task_struct *pidhash_next;
- struct task_struct **pidhash_pprev;
+ list_t pidhash_list;
wait_queue_head_t wait_chldexit; /* for wait4() */
struct completion *vfork_done; /* for vfork() */
@@ -420,37 +419,37 @@
extern struct mm_struct init_mm;
extern struct task_struct *init_tasks[NR_CPUS];
-/* PID hashing. (shouldnt this be dynamic?) */
-#define PIDHASH_SZ (4096 >> 2)
-extern struct task_struct *pidhash[PIDHASH_SZ];
+/* PID hashing. */
+extern list_t *pidhash;
+extern unsigned long pidhash_size;
-#define pid_hashfn(x) ((((x) >> 8) ^ (x)) & (PIDHASH_SZ - 1))
+static inline unsigned pid_hashfn(pid_t pid)
+{
+ return ((pid >> 8) ^ pid) & (pidhash_size - 1);
+}
static inline void hash_pid(struct task_struct *p)
{
- struct task_struct **htable = &pidhash[pid_hashfn(p->pid)];
-
- if((p->pidhash_next = *htable) != NULL)
- (*htable)->pidhash_pprev = &p->pidhash_next;
- *htable = p;
- p->pidhash_pprev = htable;
+ list_add(&p->pidhash_list, &pidhash[pid_hashfn(p->pid)]);
}
static inline void unhash_pid(struct task_struct *p)
{
- if(p->pidhash_next)
- p->pidhash_next->pidhash_pprev = p->pidhash_pprev;
- *p->pidhash_pprev = p->pidhash_next;
+ list_del(&p->pidhash_list);
}
-static inline struct task_struct *find_task_by_pid(int pid)
+static inline task_t *find_task_by_pid(int pid)
{
- struct task_struct *p, **htable = &pidhash[pid_hashfn(pid)];
+ list_t *p, *pid_list = &pidhash[pid_hashfn(pid)];
+
+ list_for_each(p, pid_list) {
+ task_t *t = list_entry(p, task_t, pidhash_list);
- for(p = *htable; p && p->pid != pid; p = p->pidhash_next)
- ;
+ if(t->pid == pid)
+ return t;
+ }
- return p;
+ return NULL;
}
/* per-UID process charging. */
diff -Nru a/kernel/fork.c b/kernel/fork.c
--- a/kernel/fork.c Fri May 10 14:40:47 2002
+++ b/kernel/fork.c Fri May 10 14:40:47 2002
@@ -44,7 +44,8 @@
unsigned long total_forks; /* Handle normal Linux uptimes. */
int last_pid;
-struct task_struct *pidhash[PIDHASH_SZ];
+list_t *pidhash;
+unsigned long pidhash_size;
rwlock_t tasklist_lock __cacheline_aligned = RW_LOCK_UNLOCKED; /* outer */
diff -Nru a/kernel/ksyms.c b/kernel/ksyms.c
--- a/kernel/ksyms.c Fri May 10 14:40:47 2002
+++ b/kernel/ksyms.c Fri May 10 14:40:47 2002
@@ -588,3 +588,4 @@
EXPORT_SYMBOL(tasklist_lock);
EXPORT_SYMBOL(pidhash);
+EXPORT_SYMBOL(pidhash_size);
diff -Nru a/kernel/sched.c b/kernel/sched.c
--- a/kernel/sched.c Fri May 10 14:40:47 2002
+++ b/kernel/sched.c Fri May 10 14:40:47 2002
@@ -15,6 +15,7 @@
#include <linux/mm.h>
#include <linux/nmi.h>
#include <linux/init.h>
+#include <linux/bootmem.h>
#include <asm/uaccess.h>
#include <linux/highmem.h>
#include <linux/smp_lock.h>
@@ -1581,7 +1582,21 @@
void __init sched_init(void)
{
runqueue_t *rq;
- int i, j, k;
+ int i, j, k, size = PAGE_SIZE*sizeof(list_t);
+
+ do {
+ pidhash = (list_t *)alloc_bootmem(size);
+ if (!pidhash)
+ size >>= 1;
+ } while (!pidhash && size >= sizeof(list_t));
+
+ if (!pidhash)
+ panic("Failed to allocated pid hash table!\n");
+
+ pidhash_size = size/sizeof(list_t);
+
+ for (i = 0; i < pidhash_size; ++i)
+ INIT_LIST_HEAD(&pidhash[i]);
for (i = 0; i < NR_CPUS; i++) {
runqueue_t *rq = cpu_rq(i);
-
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This archive was generated by hypermail 2b29 : Tue May 14 2002 - 12:00:15 EST