| Message ID | 1356350964-13437-4-git-send-email-tangchen@cn.fujitsu.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
(2012/12/24 21:09), Tang Chen wrote: > From: Wen Congyang <wency@cn.fujitsu.com> > > offlining memory blocks and checking whether memory blocks are offlined > are very similar. This patch introduces a new function to remove > redundant codes. > > Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> > --- > mm/memory_hotplug.c | 101 ++++++++++++++++++++++++++++----------------------- > 1 files changed, 55 insertions(+), 46 deletions(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index d43d97b..dbb04d8 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1381,20 +1381,14 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages) > return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ); > } > > -int remove_memory(u64 start, u64 size) please add explanation of this function here. If (*func) returns val other than 0, this function will fail and returns callback's return value...right ? > +static int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn, > + void *arg, int (*func)(struct memory_block *, void *)) > { > struct memory_block *mem = NULL; > struct mem_section *section; > - unsigned long start_pfn, end_pfn; > unsigned long pfn, section_nr; > int ret; > - int return_on_error = 0; > - int retry = 0; > - > - start_pfn = PFN_DOWN(start); > - end_pfn = start_pfn + PFN_DOWN(size); > > -repeat: Shouldn't we check lock is held here ? (VM_BUG_ON(!mutex_is_locked(&mem_hotplug_mutex); > for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { > section_nr = pfn_to_section_nr(pfn); > if (!present_section_nr(section_nr)) > @@ -1411,22 +1405,61 @@ repeat: > if (!mem) > continue; > > - ret = offline_memory_block(mem); > + ret = func(mem, arg); > if (ret) { > - if (return_on_error) { > - kobject_put(&mem->dev.kobj); > - return ret; > - } else { > - retry = 1; > - } > + kobject_put(&mem->dev.kobj); > + return ret; > } > } > > if (mem) > kobject_put(&mem->dev.kobj); > > - if (retry) { > - return_on_error = 1; > + return 0; > +} > + > +static int offline_memory_block_cb(struct memory_block *mem, void *arg) > +{ > + int *ret = arg; > + int error = offline_memory_block(mem); > + > + if (error != 0 && *ret == 0) > + *ret = error; > + > + return 0; Always returns 0 and run through all mem blocks for scan-and-retry, right ? You need explanation here ! > +} > + > +static int is_memblock_offlined_cb(struct memory_block *mem, void *arg) > +{ > + int ret = !is_memblock_offlined(mem); > + > + if (unlikely(ret)) > + pr_warn("removing memory fails, because memory " > + "[%#010llx-%#010llx] is onlined\n", > + PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)), > + PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1); > + > + return ret; > +} > + > +int remove_memory(u64 start, u64 size) > +{ > + unsigned long start_pfn, end_pfn; > + int ret = 0; > + int retry = 1; > + > + start_pfn = PFN_DOWN(start); > + end_pfn = start_pfn + PFN_DOWN(size); > + > +repeat: please explan why you repeat here . > + walk_memory_range(start_pfn, end_pfn, &ret, > + offline_memory_block_cb); > + if (ret) { > + if (!retry) > + return ret; > + > + retry = 0; > + ret = 0; > goto repeat; > } > > @@ -1444,37 +1477,13 @@ repeat: > * memory blocks are offlined. > */ > > - for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { > - section_nr = pfn_to_section_nr(pfn); > - if (!present_section_nr(section_nr)) > - continue; > - > - section = __nr_to_section(section_nr); > - /* same memblock? */ > - if (mem) > - if ((section_nr >= mem->start_section_nr) && > - (section_nr <= mem->end_section_nr)) > - continue; > - > - mem = find_memory_block_hinted(section, mem); > - if (!mem) > - continue; > - > - ret = is_memblock_offlined(mem); > - if (!ret) { > - pr_warn("removing memory fails, because memory " > - "[%#010llx-%#010llx] is onlined\n", > - PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)), > - PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1)) - 1); > - > - kobject_put(&mem->dev.kobj); > - unlock_memory_hotplug(); > - return ret; > - } please explain what you do here. confirming all memory blocks are offlined before returning 0 ....right ? > + ret = walk_memory_range(start_pfn, end_pfn, NULL, > + is_memblock_offlined_cb); > + if (ret) { > + unlock_memory_hotplug(); > + return ret; > } > > - if (mem) > - kobject_put(&mem->dev.kobj); > unlock_memory_hotplug(); > > return 0; > Thanks, -Kame -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Kamezawa-san, Thanks for the reviewing. Please see below. :) On 12/26/2012 11:20 AM, Kamezawa Hiroyuki wrote: > (2012/12/24 21:09), Tang Chen wrote: >> From: Wen Congyang<wency@cn.fujitsu.com> >> >> offlining memory blocks and checking whether memory blocks are offlined >> are very similar. This patch introduces a new function to remove >> redundant codes. >> >> Signed-off-by: Wen Congyang<wency@cn.fujitsu.com> >> --- >> mm/memory_hotplug.c | 101 ++++++++++++++++++++++++++++----------------------- >> 1 files changed, 55 insertions(+), 46 deletions(-) >> >> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >> index d43d97b..dbb04d8 100644 >> --- a/mm/memory_hotplug.c >> +++ b/mm/memory_hotplug.c >> @@ -1381,20 +1381,14 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages) >> return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ); >> } >> >> -int remove_memory(u64 start, u64 size) > > please add explanation of this function here. If (*func) returns val other than 0, > this function will fail and returns callback's return value...right ? > Yes, it will always return the func()'s return value. I'll add the comment here. :) > >> +static int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn, >> + void *arg, int (*func)(struct memory_block *, void *)) >> { >> struct memory_block *mem = NULL; >> struct mem_section *section; >> - unsigned long start_pfn, end_pfn; >> unsigned long pfn, section_nr; >> int ret; >> - int return_on_error = 0; >> - int retry = 0; >> - >> - start_pfn = PFN_DOWN(start); >> - end_pfn = start_pfn + PFN_DOWN(size); >> >> -repeat: > > Shouldn't we check lock is held here ? (VM_BUG_ON(!mutex_is_locked(&mem_hotplug_mutex); Well, I think, after applying this patch, walk_memory_range() will be a separated function. And it can be used somewhere else where we don't hold this lock. But for now, we can do this check. :) > > >> for (pfn = start_pfn; pfn< end_pfn; pfn += PAGES_PER_SECTION) { >> section_nr = pfn_to_section_nr(pfn); >> if (!present_section_nr(section_nr)) >> @@ -1411,22 +1405,61 @@ repeat: >> if (!mem) >> continue; >> >> - ret = offline_memory_block(mem); >> + ret = func(mem, arg); >> if (ret) { >> - if (return_on_error) { >> - kobject_put(&mem->dev.kobj); >> - return ret; >> - } else { >> - retry = 1; >> - } >> + kobject_put(&mem->dev.kobj); >> + return ret; >> } >> } >> >> if (mem) >> kobject_put(&mem->dev.kobj); >> >> - if (retry) { >> - return_on_error = 1; >> + return 0; >> +} >> + >> +static int offline_memory_block_cb(struct memory_block *mem, void *arg) >> +{ >> + int *ret = arg; >> + int error = offline_memory_block(mem); >> + >> + if (error != 0&& *ret == 0) >> + *ret = error; >> + >> + return 0; > > Always returns 0 and run through all mem blocks for scan-and-retry, right ? > You need explanation here ! Yes, I'll add the comment. :) > > >> +} >> + >> +static int is_memblock_offlined_cb(struct memory_block *mem, void *arg) >> +{ >> + int ret = !is_memblock_offlined(mem); >> + >> + if (unlikely(ret)) >> + pr_warn("removing memory fails, because memory " >> + "[%#010llx-%#010llx] is onlined\n", >> + PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)), >> + PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1); >> + >> + return ret; >> +} >> + >> +int remove_memory(u64 start, u64 size) >> +{ >> + unsigned long start_pfn, end_pfn; >> + int ret = 0; >> + int retry = 1; >> + >> + start_pfn = PFN_DOWN(start); >> + end_pfn = start_pfn + PFN_DOWN(size); >> + >> +repeat: > > please explan why you repeat here . This repeat is add in patch1. It aims to solve the problem we were talking about in patch1. I'll add the comment here. :) > >> + walk_memory_range(start_pfn, end_pfn,&ret, >> + offline_memory_block_cb); >> + if (ret) { >> + if (!retry) >> + return ret; >> + >> + retry = 0; >> + ret = 0; >> goto repeat; >> } >> >> @@ -1444,37 +1477,13 @@ repeat: >> * memory blocks are offlined. >> */ >> >> - for (pfn = start_pfn; pfn< end_pfn; pfn += PAGES_PER_SECTION) { >> - section_nr = pfn_to_section_nr(pfn); >> - if (!present_section_nr(section_nr)) >> - continue; >> - >> - section = __nr_to_section(section_nr); >> - /* same memblock? */ >> - if (mem) >> - if ((section_nr>= mem->start_section_nr)&& >> - (section_nr<= mem->end_section_nr)) >> - continue; >> - >> - mem = find_memory_block_hinted(section, mem); >> - if (!mem) >> - continue; >> - >> - ret = is_memblock_offlined(mem); >> - if (!ret) { >> - pr_warn("removing memory fails, because memory " >> - "[%#010llx-%#010llx] is onlined\n", >> - PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)), >> - PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1)) - 1); >> - >> - kobject_put(&mem->dev.kobj); >> - unlock_memory_hotplug(); >> - return ret; >> - } > > please explain what you do here. confirming all memory blocks are offlined > before returning 0 ....right ? Will be added. :) Thanks. :) > >> + ret = walk_memory_range(start_pfn, end_pfn, NULL, >> + is_memblock_offlined_cb); >> + if (ret) { >> + unlock_memory_hotplug(); >> + return ret; >> } >> >> - if (mem) >> - kobject_put(&mem->dev.kobj); >> unlock_memory_hotplug(); >> >> return 0; >> > > Thanks, > -Kame > > -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index d43d97b..dbb04d8 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1381,20 +1381,14 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages) return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ); } -int remove_memory(u64 start, u64 size) +static int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn, + void *arg, int (*func)(struct memory_block *, void *)) { struct memory_block *mem = NULL; struct mem_section *section; - unsigned long start_pfn, end_pfn; unsigned long pfn, section_nr; int ret; - int return_on_error = 0; - int retry = 0; - - start_pfn = PFN_DOWN(start); - end_pfn = start_pfn + PFN_DOWN(size); -repeat: for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { section_nr = pfn_to_section_nr(pfn); if (!present_section_nr(section_nr)) @@ -1411,22 +1405,61 @@ repeat: if (!mem) continue; - ret = offline_memory_block(mem); + ret = func(mem, arg); if (ret) { - if (return_on_error) { - kobject_put(&mem->dev.kobj); - return ret; - } else { - retry = 1; - } + kobject_put(&mem->dev.kobj); + return ret; } } if (mem) kobject_put(&mem->dev.kobj); - if (retry) { - return_on_error = 1; + return 0; +} + +static int offline_memory_block_cb(struct memory_block *mem, void *arg) +{ + int *ret = arg; + int error = offline_memory_block(mem); + + if (error != 0 && *ret == 0) + *ret = error; + + return 0; +} + +static int is_memblock_offlined_cb(struct memory_block *mem, void *arg) +{ + int ret = !is_memblock_offlined(mem); + + if (unlikely(ret)) + pr_warn("removing memory fails, because memory " + "[%#010llx-%#010llx] is onlined\n", + PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)), + PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1); + + return ret; +} + +int remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn, end_pfn; + int ret = 0; + int retry = 1; + + start_pfn = PFN_DOWN(start); + end_pfn = start_pfn + PFN_DOWN(size); + +repeat: + walk_memory_range(start_pfn, end_pfn, &ret, + offline_memory_block_cb); + if (ret) { + if (!retry) + return ret; + + retry = 0; + ret = 0; goto repeat; } @@ -1444,37 +1477,13 @@ repeat: * memory blocks are offlined. */ - for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { - section_nr = pfn_to_section_nr(pfn); - if (!present_section_nr(section_nr)) - continue; - - section = __nr_to_section(section_nr); - /* same memblock? */ - if (mem) - if ((section_nr >= mem->start_section_nr) && - (section_nr <= mem->end_section_nr)) - continue; - - mem = find_memory_block_hinted(section, mem); - if (!mem) - continue; - - ret = is_memblock_offlined(mem); - if (!ret) { - pr_warn("removing memory fails, because memory " - "[%#010llx-%#010llx] is onlined\n", - PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)), - PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1)) - 1); - - kobject_put(&mem->dev.kobj); - unlock_memory_hotplug(); - return ret; - } + ret = walk_memory_range(start_pfn, end_pfn, NULL, + is_memblock_offlined_cb); + if (ret) { + unlock_memory_hotplug(); + return ret; } - if (mem) - kobject_put(&mem->dev.kobj); unlock_memory_hotplug(); return 0;