From eb608e3a344b3af21300360fcf868f8b4e808a8e Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Thu, 24 May 2012 18:59:11 +0200 Subject: block: Convert BDI proportion calculations to flexible proportions Convert calculations of proportion of writeback each bdi does to new flexible proportion code. That allows us to use aging period of fixed wallclock time which gives better proportion estimates given the hugely varying throughput of different devices. Acked-by: Peter Zijlstra Signed-off-by: Jan Kara Signed-off-by: Fengguang Wu --- mm/backing-dev.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'mm/backing-dev.c') diff --git a/mm/backing-dev.c b/mm/backing-dev.c index dd8e2aafb07e..3387aea11209 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -677,7 +677,7 @@ int bdi_init(struct backing_dev_info *bdi) bdi->min_ratio = 0; bdi->max_ratio = 100; - bdi->max_prop_frac = PROP_FRAC_BASE; + bdi->max_prop_frac = FPROP_FRAC_BASE; spin_lock_init(&bdi->wb_lock); INIT_LIST_HEAD(&bdi->bdi_list); INIT_LIST_HEAD(&bdi->work_list); @@ -700,7 +700,7 @@ int bdi_init(struct backing_dev_info *bdi) bdi->write_bandwidth = INIT_BW; bdi->avg_write_bandwidth = INIT_BW; - err = prop_local_init_percpu(&bdi->completions); + err = fprop_local_init_percpu(&bdi->completions); if (err) { err: @@ -744,7 +744,7 @@ void bdi_destroy(struct backing_dev_info *bdi) for (i = 0; i < NR_BDI_STAT_ITEMS; i++) percpu_counter_destroy(&bdi->bdi_stat[i]); - prop_local_destroy_percpu(&bdi->completions); + fprop_local_destroy_percpu(&bdi->completions); } EXPORT_SYMBOL(bdi_destroy); -- cgit v1.2.3 From 3965c9ae47d64aadf6f13b6fcd37767b83c0689a Mon Sep 17 00:00:00 2001 From: Wanpeng Li Date: Tue, 31 Jul 2012 16:41:52 -0700 Subject: mm: prepare for removal of obsolete /proc/sys/vm/nr_pdflush_threads Since per-BDI flusher threads were introduced in 2.6, the pdflush mechanism is not used any more. But the old interface exported through /proc/sys/vm/nr_pdflush_threads still exists and is obviously useless. For back-compatibility, printk warning information and return 2 to notify the users that the interface is removed. Signed-off-by: Wanpeng Li Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- .../ABI/obsolete/proc-sys-vm-nr_pdflush_threads | 5 +++++ Documentation/feature-removal-schedule.txt | 8 ++++++++ Documentation/sysctl/vm.txt | 11 ----------- fs/fs-writeback.c | 5 ----- include/linux/backing-dev.h | 3 +++ include/linux/writeback.h | 5 ----- kernel/sysctl.c | 8 +++----- kernel/sysctl_binary.c | 2 +- mm/backing-dev.c | 20 ++++++++++++++++++++ 9 files changed, 40 insertions(+), 27 deletions(-) create mode 100644 Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads (limited to 'mm/backing-dev.c') diff --git a/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads b/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads new file mode 100644 index 000000000000..b0b0eeb20fe3 --- /dev/null +++ b/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads @@ -0,0 +1,5 @@ +What: /proc/sys/vm/nr_pdflush_threads +Date: June 2012 +Contact: Wanpeng Li +Description: Since pdflush is replaced by per-BDI flusher, the interface of old pdflush + exported in /proc/sys/vm/ should be removed. diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index e9237fb71950..88f2fa48bb63 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -13,6 +13,14 @@ Who: Jim Cromie , Jason Baron --------------------------- +What: /proc/sys/vm/nr_pdflush_threads +When: 2012 +Why: Since pdflush is deprecated, the interface exported in /proc/sys/vm/ + should be removed. +Who: Wanpeng Li + +--------------------------- + What: CONFIG_APM_CPU_IDLE, and its ability to call APM BIOS in idle When: 2012 Why: This optional sub-feature of APM is of dubious reliability, diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 84eb25cd69aa..06d662b1c5d5 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -42,7 +42,6 @@ Currently, these files are in /proc/sys/vm: - mmap_min_addr - nr_hugepages - nr_overcommit_hugepages -- nr_pdflush_threads - nr_trim_pages (only if CONFIG_MMU=n) - numa_zonelist_order - oom_dump_tasks @@ -426,16 +425,6 @@ See Documentation/vm/hugetlbpage.txt ============================================================== -nr_pdflush_threads - -The current number of pdflush threads. This value is read-only. -The value changes according to the number of dirty pages in the system. - -When necessary, additional pdflush threads are created, one per second, up to -nr_pdflush_threads_max. - -============================================================== - nr_trim_pages This is available only on NOMMU kernels. diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 50d0b78130a1..be3efc4f64f4 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -52,11 +52,6 @@ struct wb_writeback_work { struct completion *done; /* set if the caller waits */ }; -/* - * We don't actually have pdflush, but this one is exported though /proc... - */ -int nr_pdflush_threads; - /** * writeback_in_progress - determine whether there is writeback in progress * @bdi: the device's backing_dev_info structure. diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 489de625cd25..c97c6b9cd38e 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -17,6 +17,7 @@ #include #include #include +#include struct page; struct device; @@ -304,6 +305,8 @@ void clear_bdi_congested(struct backing_dev_info *bdi, int sync); void set_bdi_congested(struct backing_dev_info *bdi, int sync); long congestion_wait(int sync, long timeout); long wait_iff_congested(struct zone *zone, int sync, long timeout); +int pdflush_proc_obsolete(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos); static inline bool bdi_cap_writeback_dirty(struct backing_dev_info *bdi) { diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 6d0a0fcd80e7..c66fe3332d83 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -189,9 +189,4 @@ void tag_pages_for_writeback(struct address_space *mapping, void account_page_redirty(struct page *page); -/* pdflush.c */ -extern int nr_pdflush_threads; /* Global so it can be exported to sysctl - read-only. */ - - #endif /* WRITEBACK_H */ diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 97186b99b0e4..6502d35a25ba 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1101,11 +1101,9 @@ static struct ctl_table vm_table[] = { .extra1 = &zero, }, { - .procname = "nr_pdflush_threads", - .data = &nr_pdflush_threads, - .maxlen = sizeof nr_pdflush_threads, - .mode = 0444 /* read-only*/, - .proc_handler = proc_dointvec, + .procname = "nr_pdflush_threads", + .mode = 0444 /* read-only */, + .proc_handler = pdflush_proc_obsolete, }, { .procname = "swappiness", diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c index a650694883a1..65bdcf198d4e 100644 --- a/kernel/sysctl_binary.c +++ b/kernel/sysctl_binary.c @@ -147,7 +147,7 @@ static const struct bin_table bin_vm_table[] = { { CTL_INT, VM_DIRTY_RATIO, "dirty_ratio" }, /* VM_DIRTY_WB_CS "dirty_writeback_centisecs" no longer used */ /* VM_DIRTY_EXPIRE_CS "dirty_expire_centisecs" no longer used */ - { CTL_INT, VM_NR_PDFLUSH_THREADS, "nr_pdflush_threads" }, + /* VM_NR_PDFLUSH_THREADS "nr_pdflush_threads" no longer used */ { CTL_INT, VM_OVERCOMMIT_RATIO, "overcommit_ratio" }, /* VM_PAGEBUF unused */ /* VM_HUGETLB_PAGES "nr_hugepages" no longer used */ diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 3387aea11209..6b4718e2ee34 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -886,3 +886,23 @@ out: return ret; } EXPORT_SYMBOL(wait_iff_congested); + +int pdflush_proc_obsolete(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + char kbuf[] = "0\n"; + + if (*ppos) { + *lenp = 0; + return 0; + } + + if (copy_to_user(buffer, kbuf, sizeof(kbuf))) + return -EFAULT; + printk_once(KERN_WARNING "%s exported in /proc is scheduled for removal\n", + table->procname); + + *lenp = 2; + *ppos += *lenp; + return 2; +} -- cgit v1.2.3