| Message ID | 20240826120449.1666461-13-yukaixiong@huawei.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | sysctl: move sysctls from vm_table into its own files | expand |
On Mon, Aug 26, 2024 at 08:04:46PM +0800, Kaixiong Yu wrote: > The sysctl_vfs_cache_pressure belongs to fs/dcache.c, move it to > its own file from kernel/sysctl.c. As a part of fs/dcache.c cleaning, > sysctl_vfs_cache_pressure is changed to a static variable, and export > vfs_pressure_ratio with EXPORT_SYMBOL_GPL to be used by other files. > And move the unneeded include(linux/dcache.h). > > Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com> > --- > fs/dcache.c | 21 +++++++++++++++++++-- > include/linux/dcache.h | 7 +------ > kernel/sysctl.c | 9 --------- > 3 files changed, 20 insertions(+), 17 deletions(-) > > diff --git a/fs/dcache.c b/fs/dcache.c > index 1af75fa68638..8717d5026cda 100644 > --- a/fs/dcache.c > +++ b/fs/dcache.c > @@ -73,8 +73,13 @@ > * If no ancestor relationship: > * arbitrary, since it's serialized on rename_lock > */ > -int sysctl_vfs_cache_pressure __read_mostly = 100; > -EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure); > +static int sysctl_vfs_cache_pressure __read_mostly = 100; > + > +unsigned long vfs_pressure_ratio(unsigned long val) > +{ > + return mult_frac(val, sysctl_vfs_cache_pressure, 100); > +} > +EXPORT_SYMBOL_GPL(vfs_pressure_ratio); This was a static inline, but AFAICT it's only called through alloc_super() which is hardly "fast path". If this series gets another version it may be worth calling out this inline->out-of-line change in the commit log. I don't think it's a blocker, but I'm not a VFS maintainer. :)
On Mon 26-08-24 12:56:00, Kees Cook wrote: > On Mon, Aug 26, 2024 at 08:04:46PM +0800, Kaixiong Yu wrote: > > The sysctl_vfs_cache_pressure belongs to fs/dcache.c, move it to > > its own file from kernel/sysctl.c. As a part of fs/dcache.c cleaning, > > sysctl_vfs_cache_pressure is changed to a static variable, and export > > vfs_pressure_ratio with EXPORT_SYMBOL_GPL to be used by other files. > > And move the unneeded include(linux/dcache.h). > > > > Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com> > > --- > > fs/dcache.c | 21 +++++++++++++++++++-- > > include/linux/dcache.h | 7 +------ > > kernel/sysctl.c | 9 --------- > > 3 files changed, 20 insertions(+), 17 deletions(-) > > > > diff --git a/fs/dcache.c b/fs/dcache.c > > index 1af75fa68638..8717d5026cda 100644 > > --- a/fs/dcache.c > > +++ b/fs/dcache.c > > @@ -73,8 +73,13 @@ > > * If no ancestor relationship: > > * arbitrary, since it's serialized on rename_lock > > */ > > -int sysctl_vfs_cache_pressure __read_mostly = 100; > > -EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure); > > +static int sysctl_vfs_cache_pressure __read_mostly = 100; > > + > > +unsigned long vfs_pressure_ratio(unsigned long val) > > +{ > > + return mult_frac(val, sysctl_vfs_cache_pressure, 100); > > +} > > +EXPORT_SYMBOL_GPL(vfs_pressure_ratio); > > This was a static inline, but AFAICT it's only called through > alloc_super() which is hardly "fast path". If this series gets another > version it may be worth calling out this inline->out-of-line change in > the commit log. > > I don't think it's a blocker, but I'm not a VFS maintainer. :) It's actually called from about 7 shrinkers of filesystem objects. They get called relatively frequently during memory reclaim but I don't think a function call is *that* expensive to matter in this case. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza
On Mon, Aug 26, 2024 at 08:04:46PM GMT, Kaixiong Yu wrote: > The sysctl_vfs_cache_pressure belongs to fs/dcache.c, move it to > its own file from kernel/sysctl.c. As a part of fs/dcache.c cleaning, > sysctl_vfs_cache_pressure is changed to a static variable, and export > vfs_pressure_ratio with EXPORT_SYMBOL_GPL to be used by other files. > And move the unneeded include(linux/dcache.h). > > Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com> > --- Reviewed-by: Christian Brauner <brauner@kernel.org>
diff --git a/fs/dcache.c b/fs/dcache.c index 1af75fa68638..8717d5026cda 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -73,8 +73,13 @@ * If no ancestor relationship: * arbitrary, since it's serialized on rename_lock */ -int sysctl_vfs_cache_pressure __read_mostly = 100; -EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure); +static int sysctl_vfs_cache_pressure __read_mostly = 100; + +unsigned long vfs_pressure_ratio(unsigned long val) +{ + return mult_frac(val, sysctl_vfs_cache_pressure, 100); +} +EXPORT_SYMBOL_GPL(vfs_pressure_ratio); __cacheline_aligned_in_smp DEFINE_SEQLOCK(rename_lock); @@ -196,8 +201,20 @@ static struct ctl_table fs_dcache_sysctls[] = { }, }; +static struct ctl_table vm_dcache_sysctls[] = { + { + .procname = "vfs_cache_pressure", + .data = &sysctl_vfs_cache_pressure, + .maxlen = sizeof(sysctl_vfs_cache_pressure), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + }, +}; + static int __init init_fs_dcache_sysctls(void) { + register_sysctl_init("vm", vm_dcache_sysctls); register_sysctl_init("fs", fs_dcache_sysctls); return 0; } diff --git a/include/linux/dcache.h b/include/linux/dcache.h index bff956f7b2b9..c81c2e9e13df 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -508,12 +508,7 @@ static inline int simple_positive(const struct dentry *dentry) return d_really_is_positive(dentry) && !d_unhashed(dentry); } -extern int sysctl_vfs_cache_pressure; - -static inline unsigned long vfs_pressure_ratio(unsigned long val) -{ - return mult_frac(val, sysctl_vfs_cache_pressure, 100); -} +unsigned long vfs_pressure_ratio(unsigned long val); /** * d_inode - Get the actual inode of this dentry diff --git a/kernel/sysctl.c b/kernel/sysctl.c index d638a1bac9af..6f03fc749794 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -46,7 +46,6 @@ #include <linux/key.h> #include <linux/times.h> #include <linux/limits.h> -#include <linux/dcache.h> #include <linux/syscalls.h> #include <linux/nfs_fs.h> #include <linux/acpi.h> @@ -2024,14 +2023,6 @@ static struct ctl_table kern_table[] = { }; static struct ctl_table vm_table[] = { - { - .procname = "vfs_cache_pressure", - .data = &sysctl_vfs_cache_pressure, - .maxlen = sizeof(sysctl_vfs_cache_pressure), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - }, #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \ (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL)) {
The sysctl_vfs_cache_pressure belongs to fs/dcache.c, move it to its own file from kernel/sysctl.c. As a part of fs/dcache.c cleaning, sysctl_vfs_cache_pressure is changed to a static variable, and export vfs_pressure_ratio with EXPORT_SYMBOL_GPL to be used by other files. And move the unneeded include(linux/dcache.h). Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com> --- fs/dcache.c | 21 +++++++++++++++++++-- include/linux/dcache.h | 7 +------ kernel/sysctl.c | 9 --------- 3 files changed, 20 insertions(+), 17 deletions(-)