From a1c3bfb2f67ef766de03f1f56bdfff9c8595ab14 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Wed, 29 Jan 2014 14:05:41 -0800 Subject: mm/page-writeback.c: do not count anon pages as dirtyable memory The VM is currently heavily tuned to avoid swapping. Whether that is good or bad is a separate discussion, but as long as the VM won't swap to make room for dirty cache, we can not consider anonymous pages when calculating the amount of dirtyable memory, the baseline to which dirty_background_ratio and dirty_ratio are applied. A simple workload that occupies a significant size (40+%, depending on memory layout, storage speeds etc.) of memory with anon/tmpfs pages and uses the remainder for a streaming writer demonstrates this problem. In that case, the actual cache pages are a small fraction of what is considered dirtyable overall, which results in an relatively large portion of the cache pages to be dirtied. As kswapd starts rotating these, random tasks enter direct reclaim and stall on IO. Only consider free pages and file pages dirtyable. Signed-off-by: Johannes Weiner Reported-by: Tejun Heo Tested-by: Tejun Heo Reviewed-by: Rik van Riel Cc: Mel Gorman Cc: Wu Fengguang Reviewed-by: Michal Hocko Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/vmstat.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h index e4b948080d20..a67b38415768 100644 --- a/include/linux/vmstat.h +++ b/include/linux/vmstat.h @@ -142,8 +142,6 @@ static inline unsigned long zone_page_state_snapshot(struct zone *zone, return x; } -extern unsigned long global_reclaimable_pages(void); - #ifdef CONFIG_NUMA /* * Determine the per node value of a stat item. This function -- cgit v1.2.3 From dfd948e32af2e7b28bcd7a490c0a30d4b8df2a36 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 29 Jan 2014 14:05:44 -0800 Subject: fs/compat: fix parameter handling for compat readv/writev syscalls We got a report that the pwritev syscall does not work correctly in compat mode on s390. It turned out that with commit 72ec35163f9f ("switch compat readv/writev variants to COMPAT_SYSCALL_DEFINE") we lost the zero extension of a couple of syscall parameters because the some parameter types haven't been converted from unsigned long to compat_ulong_t. This is needed for architectures where the ABI requires that the caller of a function performed zero and/or sign extension to 64 bit of all parameters. Signed-off-by: Heiko Carstens Cc: Al Viro Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Hendrik Brueckner Cc: Martin Schwidefsky Cc: [v3.10+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/read_write.c | 16 ++++++++-------- include/linux/compat.h | 16 ++++++++-------- 2 files changed, 16 insertions(+), 16 deletions(-) (limited to 'include/linux') diff --git a/fs/read_write.c b/fs/read_write.c index 1193ffd03565..edc5746a902a 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -964,9 +964,9 @@ out: return ret; } -COMPAT_SYSCALL_DEFINE3(readv, unsigned long, fd, +COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, const struct compat_iovec __user *,vec, - unsigned long, vlen) + compat_ulong_t, vlen) { struct fd f = fdget(fd); ssize_t ret; @@ -1001,9 +1001,9 @@ COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, return ret; } -COMPAT_SYSCALL_DEFINE5(preadv, unsigned long, fd, +COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, const struct compat_iovec __user *,vec, - unsigned long, vlen, u32, pos_low, u32, pos_high) + compat_ulong_t, vlen, u32, pos_low, u32, pos_high) { loff_t pos = ((loff_t)pos_high << 32) | pos_low; return compat_sys_preadv64(fd, vec, vlen, pos); @@ -1031,9 +1031,9 @@ out: return ret; } -COMPAT_SYSCALL_DEFINE3(writev, unsigned long, fd, +COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, const struct compat_iovec __user *, vec, - unsigned long, vlen) + compat_ulong_t, vlen) { struct fd f = fdget(fd); ssize_t ret; @@ -1068,9 +1068,9 @@ COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, return ret; } -COMPAT_SYSCALL_DEFINE5(pwritev, unsigned long, fd, +COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, const struct compat_iovec __user *,vec, - unsigned long, vlen, u32, pos_low, u32, pos_high) + compat_ulong_t, vlen, u32, pos_low, u32, pos_high) { loff_t pos = ((loff_t)pos_high << 32) | pos_low; return compat_sys_pwritev64(fd, vec, vlen, pos); diff --git a/include/linux/compat.h b/include/linux/compat.h index eb8a49d75ab3..c5642b83e02b 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -327,16 +327,16 @@ asmlinkage long compat_sys_keyctl(u32 option, u32 arg2, u32 arg3, u32 arg4, u32 arg5); asmlinkage long compat_sys_ustat(unsigned dev, struct compat_ustat __user *u32); -asmlinkage ssize_t compat_sys_readv(unsigned long fd, - const struct compat_iovec __user *vec, unsigned long vlen); -asmlinkage ssize_t compat_sys_writev(unsigned long fd, - const struct compat_iovec __user *vec, unsigned long vlen); -asmlinkage ssize_t compat_sys_preadv(unsigned long fd, +asmlinkage ssize_t compat_sys_readv(compat_ulong_t fd, + const struct compat_iovec __user *vec, compat_ulong_t vlen); +asmlinkage ssize_t compat_sys_writev(compat_ulong_t fd, + const struct compat_iovec __user *vec, compat_ulong_t vlen); +asmlinkage ssize_t compat_sys_preadv(compat_ulong_t fd, const struct compat_iovec __user *vec, - unsigned long vlen, u32 pos_low, u32 pos_high); -asmlinkage ssize_t compat_sys_pwritev(unsigned long fd, + compat_ulong_t vlen, u32 pos_low, u32 pos_high); +asmlinkage ssize_t compat_sys_pwritev(compat_ulong_t fd, const struct compat_iovec __user *vec, - unsigned long vlen, u32 pos_low, u32 pos_high); + compat_ulong_t vlen, u32 pos_low, u32 pos_high); asmlinkage long comat_sys_lseek(unsigned int, compat_off_t, unsigned int); asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr_t __user *argv, -- cgit v1.2.3 From d8d14bd09cddbaf0168d61af638455a26bd027ff Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 29 Jan 2014 14:05:46 -0800 Subject: fs/compat: fix lookup_dcookie() parameter handling Commit d5dc77bfeeab ("consolidate compat lookup_dcookie()") coverted all architectures to the new compat_sys_lookup_dcookie() syscall. The "len" paramater of the new compat syscall must have the type compat_size_t in order to enforce zero extension for architectures where the ABI requires that the caller of a function performed zero and/or sign extension to 64 bit of all parameters. Signed-off-by: Heiko Carstens Cc: Al Viro Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Hendrik Brueckner Cc: Martin Schwidefsky Cc: [v3.10+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/dcookies.c | 2 +- include/linux/compat.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/fs/dcookies.c b/fs/dcookies.c index ab5954b50267..ac44a69fbea9 100644 --- a/fs/dcookies.c +++ b/fs/dcookies.c @@ -204,7 +204,7 @@ out: } #ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE4(lookup_dcookie, u32, w0, u32, w1, char __user *, buf, size_t, len) +COMPAT_SYSCALL_DEFINE4(lookup_dcookie, u32, w0, u32, w1, char __user *, buf, compat_size_t, len) { #ifdef __BIG_ENDIAN return sys_lookup_dcookie(((u64)w0 << 32) | w1, buf, len); diff --git a/include/linux/compat.h b/include/linux/compat.h index c5642b83e02b..19f6003291de 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -422,7 +422,7 @@ extern long compat_arch_ptrace(struct task_struct *child, compat_long_t request, asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid, compat_long_t addr, compat_long_t data); -asmlinkage long compat_sys_lookup_dcookie(u32, u32, char __user *, size_t); +asmlinkage long compat_sys_lookup_dcookie(u32, u32, char __user *, compat_size_t); /* * epoll (fs/eventpoll.c) compat bits follow ... */ -- cgit v1.2.3