From: Hideo AOKI This patch adds "swap_token_timeout" parameter in /proc/sys/vm. The parameter means expired time of token. Unit of the value is HZ, and the default value is the same as current SWAP_TOKEN_TIMEOUT (i.e. HZ * 300). Signed-off-by: Hideo Aoki Signed-off-by: Andrew Morton --- 25-akpm/include/linux/swap.h | 1 + 25-akpm/include/linux/sysctl.h | 1 + 25-akpm/kernel/sysctl.c | 9 +++++++++ 25-akpm/mm/thrash.c | 5 +++-- 4 files changed, 14 insertions(+), 2 deletions(-) diff -puN include/linux/swap.h~vm-thrashing-control-tuning include/linux/swap.h --- 25/include/linux/swap.h~vm-thrashing-control-tuning Wed Oct 6 15:48:32 2004 +++ 25-akpm/include/linux/swap.h Wed Oct 6 15:48:32 2004 @@ -230,6 +230,7 @@ extern spinlock_t swaplock; /* linux/mm/thrash.c */ extern struct mm_struct * swap_token_mm; +extern unsigned long swap_token_default_timeout; extern void grab_swap_token(void); extern void __put_swap_token(struct mm_struct *); diff -puN include/linux/sysctl.h~vm-thrashing-control-tuning include/linux/sysctl.h --- 25/include/linux/sysctl.h~vm-thrashing-control-tuning Wed Oct 6 15:48:32 2004 +++ 25-akpm/include/linux/sysctl.h Wed Oct 6 15:48:57 2004 @@ -168,6 +168,7 @@ enum VM_VFS_CACHE_PRESSURE=26, /* dcache/icache reclaim pressure */ VM_LEGACY_VA_LAYOUT=27, /* legacy/compatibility virtual address space layout */ VM_HEAP_STACK_GAP=28, /* int: page gap between heap and stack */ + VM_SWAP_TOKEN_TIMEOUT=28, /* default time for token time out */ }; diff -puN kernel/sysctl.c~vm-thrashing-control-tuning kernel/sysctl.c --- 25/kernel/sysctl.c~vm-thrashing-control-tuning Wed Oct 6 15:48:32 2004 +++ 25-akpm/kernel/sysctl.c Wed Oct 6 15:48:32 2004 @@ -624,6 +624,15 @@ static ctl_table kern_table[] = { .proc_handler = &proc_unknown_nmi_panic, }, #endif + { + .ctl_name = VM_SWAP_TOKEN_TIMEOUT, + .procname = "swap_token_timeout", + .data = &swap_token_default_timeout, + .maxlen = sizeof(swap_token_default_timeout), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, { .ctl_name = 0 } }; diff -puN mm/thrash.c~vm-thrashing-control-tuning mm/thrash.c --- 25/mm/thrash.c~vm-thrashing-control-tuning Wed Oct 6 15:48:32 2004 +++ 25-akpm/mm/thrash.c Wed Oct 6 15:48:32 2004 @@ -20,6 +20,7 @@ struct mm_struct * swap_token_mm = &init #define SWAP_TOKEN_CHECK_INTERVAL (HZ * 2) #define SWAP_TOKEN_TIMEOUT (HZ * 300) +unsigned long swap_token_default_timeout = SWAP_TOKEN_TIMEOUT; /* * Take the token away if the process had no page faults @@ -75,10 +76,10 @@ void grab_swap_token(void) if ((reason = should_release_swap_token(mm))) { unsigned long eligible = jiffies; if (reason == SWAP_TOKEN_TIMED_OUT) { - eligible += SWAP_TOKEN_TIMEOUT; + eligible += swap_token_default_timeout; } mm->swap_token_time = eligible; - swap_token_timeout = jiffies + SWAP_TOKEN_TIMEOUT; + swap_token_timeout = jiffies + swap_token_default_timeout; swap_token_mm = current->mm; } spin_unlock(&swap_token_lock); _