| Message ID | 20240410184217.1482366-4-andrew.cooper3@citrix.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | xen/arch: Simplify virtual_region setup | expand |
Hi Andrew, On 10/04/2024 20:42, Andrew Cooper wrote: > > > Given 3 statically initialised objects, its easy to link the list at build > time. There's no need to do it during runtime at boot (and with IRQs-off, > even). > > As a consequence, register_virtual_region() can now move inside ifdef > CONFIG_LIVEPATCH like unregister_virtual_region(). > > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Michal Orzel <michal.orzel@amd.com> Maybe with ... > --- > CC: Jan Beulich <JBeulich@suse.com> > CC: Roger Pau Monné <roger.pau@citrix.com> > CC: Wei Liu <wl@xen.org> > CC: Stefano Stabellini <sstabellini@kernel.org> > CC: Julien Grall <julien@xen.org> > CC: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com> > CC: Bertrand Marquis <bertrand.marquis@arm.com> > CC: Michal Orzel <michal.orzel@amd.com> > CC: Oleksii Kurochko <oleksii.kurochko@gmail.com> > CC: Shawn Anastasio <sanastasio@raptorengineering.com> > CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > CC: Ross Lagerwall <ross.lagerwall@citrix.com> > > v2: > * Collect the initialisers togoether too. > --- > xen/common/virtual_region.c | 37 ++++++++++++++++++++++--------------- > 1 file changed, 22 insertions(+), 15 deletions(-) > > diff --git a/xen/common/virtual_region.c b/xen/common/virtual_region.c > index 7d8bdeb61282..db3e0dc9fe74 100644 > --- a/xen/common/virtual_region.c > +++ b/xen/common/virtual_region.c > @@ -15,8 +15,18 @@ extern const struct bug_frame > __start_bug_frames_2[], __stop_bug_frames_2[], > __start_bug_frames_3[], __stop_bug_frames_3[]; > > +/* > + * For the built-in regions, the double linked list can be constructed at > + * build time. Forward-declare the elements and their initialisers. > + */ > +static struct list_head virtual_region_list; > +static struct virtual_region core, core_init; ... empty line here for better readability > +#define LIST_ENTRY_HEAD() { .next = &core.list, .prev = &core_init.list } > +#define LIST_ENTRY_CORE() { .next = &core_init.list, .prev = &virtual_region_list } > +#define LIST_ENTRY_INIT() { .next = &virtual_region_list, .prev = &core.list } ~Michal
On 11/04/2024 7:34 am, Michal Orzel wrote: > Hi Andrew, > > On 10/04/2024 20:42, Andrew Cooper wrote: >> diff --git a/xen/common/virtual_region.c b/xen/common/virtual_region.c >> index 7d8bdeb61282..db3e0dc9fe74 100644 >> --- a/xen/common/virtual_region.c >> +++ b/xen/common/virtual_region.c >> @@ -15,8 +15,18 @@ extern const struct bug_frame >> __start_bug_frames_2[], __stop_bug_frames_2[], >> __start_bug_frames_3[], __stop_bug_frames_3[]; >> >> +/* >> + * For the built-in regions, the double linked list can be constructed at >> + * build time. Forward-declare the elements and their initialisers. >> + */ >> +static struct list_head virtual_region_list; >> +static struct virtual_region core, core_init; > ... empty line here for better readability Will do. Thanks. ~Andrew
diff --git a/xen/common/virtual_region.c b/xen/common/virtual_region.c index 7d8bdeb61282..db3e0dc9fe74 100644 --- a/xen/common/virtual_region.c +++ b/xen/common/virtual_region.c @@ -15,8 +15,18 @@ extern const struct bug_frame __start_bug_frames_2[], __stop_bug_frames_2[], __start_bug_frames_3[], __stop_bug_frames_3[]; +/* + * For the built-in regions, the double linked list can be constructed at + * build time. Forward-declare the elements and their initialisers. + */ +static struct list_head virtual_region_list; +static struct virtual_region core, core_init; +#define LIST_ENTRY_HEAD() { .next = &core.list, .prev = &core_init.list } +#define LIST_ENTRY_CORE() { .next = &core_init.list, .prev = &virtual_region_list } +#define LIST_ENTRY_INIT() { .next = &virtual_region_list, .prev = &core.list } + static struct virtual_region core = { - .list = LIST_HEAD_INIT(core.list), + .list = LIST_ENTRY_CORE(), .text_start = _stext, .text_end = _etext, .rodata_start = _srodata, @@ -32,7 +42,7 @@ static struct virtual_region core = { /* Becomes irrelevant when __init sections are cleared. */ static struct virtual_region core_init __initdata = { - .list = LIST_HEAD_INIT(core_init.list), + .list = LIST_ENTRY_INIT(), .text_start = _sinittext, .text_end = _einittext, @@ -50,7 +60,7 @@ static struct virtual_region core_init __initdata = { * * All readers of virtual_region_list MUST use list_for_each_entry_rcu. */ -static LIST_HEAD(virtual_region_list); +static struct list_head virtual_region_list = LIST_ENTRY_HEAD(); static DEFINE_SPINLOCK(virtual_region_lock); static DEFINE_RCU_READ_LOCK(rcu_virtual_region_lock); @@ -73,15 +83,6 @@ const struct virtual_region *find_text_region(unsigned long addr) return region; } -void register_virtual_region(struct virtual_region *r) -{ - unsigned long flags; - - spin_lock_irqsave(&virtual_region_lock, flags); - list_add_tail_rcu(&r->list, &virtual_region_list); - spin_unlock_irqrestore(&virtual_region_lock, flags); -} - /* * Suggest inline so when !CONFIG_LIVEPATCH the function is not left * unreachable after init code is removed. @@ -96,6 +97,15 @@ static void inline remove_virtual_region(struct virtual_region *r) } #ifdef CONFIG_LIVEPATCH +void register_virtual_region(struct virtual_region *r) +{ + unsigned long flags; + + spin_lock_irqsave(&virtual_region_lock, flags); + list_add_tail_rcu(&r->list, &virtual_region_list); + spin_unlock_irqrestore(&virtual_region_lock, flags); +} + void unregister_virtual_region(struct virtual_region *r) { remove_virtual_region(r); @@ -155,9 +165,6 @@ void __init setup_virtual_regions(const struct exception_table_entry *start, { core_init.ex = core.ex = start; core_init.ex_end = core.ex_end = end; - - register_virtual_region(&core_init); - register_virtual_region(&core); } /*
Given 3 statically initialised objects, its easy to link the list at build time. There's no need to do it during runtime at boot (and with IRQs-off, even). As a consequence, register_virtual_region() can now move inside ifdef CONFIG_LIVEPATCH like unregister_virtual_region(). Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> --- CC: Jan Beulich <JBeulich@suse.com> CC: Roger Pau Monné <roger.pau@citrix.com> CC: Wei Liu <wl@xen.org> CC: Stefano Stabellini <sstabellini@kernel.org> CC: Julien Grall <julien@xen.org> CC: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com> CC: Bertrand Marquis <bertrand.marquis@arm.com> CC: Michal Orzel <michal.orzel@amd.com> CC: Oleksii Kurochko <oleksii.kurochko@gmail.com> CC: Shawn Anastasio <sanastasio@raptorengineering.com> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: Ross Lagerwall <ross.lagerwall@citrix.com> v2: * Collect the initialisers togoether too. --- xen/common/virtual_region.c | 37 ++++++++++++++++++++++--------------- 1 file changed, 22 insertions(+), 15 deletions(-)