From da4276b8299a6544dc41ac2485d3ffca5811b3fb Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 7 Jan 2009 11:05:10 +0100 Subject: x86: offer frame pointers in all build modes CONFIG_FRAME_POINTERS=y results in much better debug info for the kernel (clear and precise backtraces), with the only drawback being a ~1% increase in kernel size. So offer it unconditionally and enable it by default. Signed-off-by: Ingo Molnar --- lib/Kconfig.debug | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 2e75478e9c69..2d0f14490174 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -566,14 +566,14 @@ config DEBUG_NOTIFIERS config FRAME_POINTER bool "Compile the kernel with frame pointers" depends on DEBUG_KERNEL && \ - (X86 || CRIS || M68K || M68KNOMMU || FRV || UML || S390 || \ - AVR32 || SUPERH || BLACKFIN || MN10300) - default y if DEBUG_INFO && UML - help - If you say Y here the resulting kernel image will be slightly larger - and slower, but it might give very useful debugging information on - some architectures or if you use external debuggers. - If you don't debug the kernel, you can say N. + (CRIS || M68K || M68KNOMMU || FRV || UML || S390 || \ + AVR32 || SUPERH || BLACKFIN || MN10300) || \ + ARCH_WANT_FRAME_POINTERS + default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS + help + If you say Y here the resulting kernel image will be slightly + larger and slower, but it gives very useful debugging information + in case of kernel bugs. (precise oopses/stacktraces/warnings) config BOOT_PRINTK_DELAY bool "Delay each boot printk message by N milliseconds" -- cgit v1.2.2 From 8feae13110d60cc6287afabc2887366b0eb226c2 Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 8 Jan 2009 12:04:47 +0000 Subject: NOMMU: Make VMAs per MM as for MMU-mode linux Make VMAs per mm_struct as for MMU-mode linux. This solves two problems: (1) In SYSV SHM where nattch for a segment does not reflect the number of shmat's (and forks) done. (2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an exec'ing process when VM_EXECUTABLE is specified, regardless of the fact that a VMA might be shared and already have its vm_mm assigned to another process or a dead process. A new struct (vm_region) is introduced to track a mapped region and to remember the circumstances under which it may be shared and the vm_list_struct structure is discarded as it's no longer required. This patch makes the following additional changes: (1) Regions are now allocated with alloc_pages() rather than kmalloc() and with no recourse to __GFP_COMP, so the pages are not composite. Instead, each page has a reference on it held by the region. Anything else that is interested in such a page will have to get a reference on it to retain it. When the pages are released due to unmapping, each page is passed to put_page() and will be freed when the page usage count reaches zero. (2) Excess pages are trimmed after an allocation as the allocation must be made as a power-of-2 quantity of pages. (3) VMAs are added to the parent MM's R/B tree and mmap lists. As an MM may end up with overlapping VMAs within the tree, the VMA struct address is appended to the sort key. (4) Non-anonymous VMAs are now added to the backing inode's prio list. (5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of the backing region. The VMA and region structs will be split if necessary. (6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory segment instead of all the attachments at that addresss. Multiple shmat()'s return the same address under NOMMU-mode instead of different virtual addresses as under MMU-mode. (7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode. (8) /proc/maps is now the global list of mapped regions, and may list bits that aren't actually mapped anywhere. (9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount of RAM currently allocated by mmap to hold mappable regions that can't be mapped directly. These are copies of the backing device or file if not anonymous. These changes make NOMMU mode more similar to MMU mode. The downside is that NOMMU mode requires some extra memory to track things over NOMMU without this patch (VMAs are no longer shared, and there are now region structs). Signed-off-by: David Howells Tested-by: Mike Frysinger Acked-by: Paul Mundt --- lib/Kconfig.debug | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 2e75478e9c69..d0a32aab03ff 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -512,6 +512,13 @@ config DEBUG_VIRTUAL If unsure, say N. +config DEBUG_NOMMU_REGIONS + bool "Debug the global anon/private NOMMU mapping region tree" + depends on DEBUG_KERNEL && !MMU + help + This option causes the global tree of anonymous and private mapping + regions to be regularly checked for invalid topology. + config DEBUG_WRITECOUNT bool "Debug filesystem writers count" depends on DEBUG_KERNEL -- cgit v1.2.2 From b53907c0100a353a7ac53bed260e735e5ccbbbcc Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Wed, 7 Jan 2009 18:09:11 -0800 Subject: generic swap(): lib/sort.c: rename swap to swap_func This is to avoid name clashes for the introduction of a global swap() macro. Signed-off-by: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/sort.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) (limited to 'lib') diff --git a/lib/sort.c b/lib/sort.c index 6abbaf3d5858..926d00429ed2 100644 --- a/lib/sort.c +++ b/lib/sort.c @@ -32,11 +32,11 @@ static void generic_swap(void *a, void *b, int size) * @base: pointer to data to sort * @num: number of elements * @size: size of each element - * @cmp: pointer to comparison function - * @swap: pointer to swap function or NULL + * @cmp_func: pointer to comparison function + * @swap_func: pointer to swap function or NULL * * This function does a heapsort on the given array. You may provide a - * swap function optimized to your element type. + * swap_func function optimized to your element type. * * Sorting time is O(n log n) both on average and worst-case. While * qsort is about 20% faster on average, it suffers from exploitable @@ -45,37 +45,39 @@ static void generic_swap(void *a, void *b, int size) */ void sort(void *base, size_t num, size_t size, - int (*cmp)(const void *, const void *), - void (*swap)(void *, void *, int size)) + int (*cmp_func)(const void *, const void *), + void (*swap_func)(void *, void *, int size)) { /* pre-scale counters for performance */ int i = (num/2 - 1) * size, n = num * size, c, r; - if (!swap) - swap = (size == 4 ? u32_swap : generic_swap); + if (!swap_func) + swap_func = (size == 4 ? u32_swap : generic_swap); /* heapify */ for ( ; i >= 0; i -= size) { for (r = i; r * 2 + size < n; r = c) { c = r * 2 + size; - if (c < n - size && cmp(base + c, base + c + size) < 0) + if (c < n - size && + cmp_func(base + c, base + c + size) < 0) c += size; - if (cmp(base + r, base + c) >= 0) + if (cmp_func(base + r, base + c) >= 0) break; - swap(base + r, base + c, size); + swap_func(base + r, base + c, size); } } /* sort */ for (i = n - size; i > 0; i -= size) { - swap(base, base + i, size); + swap_func(base, base + i, size); for (r = 0; r * 2 + size < i; r = c) { c = r * 2 + size; - if (c < i - size && cmp(base + c, base + c + size) < 0) + if (c < i - size && + cmp_func(base + c, base + c + size) < 0) c += size; - if (cmp(base + r, base + c) >= 0) + if (cmp_func(base + r, base + c) >= 0) break; - swap(base + r, base + c, size); + swap_func(base + r, base + c, size); } } } -- cgit v1.2.2 From f4b477c47332367d35686bd2b808c2156b96d7c7 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Sat, 10 Jan 2009 11:12:09 +0000 Subject: rbtree: add const qualifier to some functions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The 'rb_first()', 'rb_last()', 'rb_next()' and 'rb_prev()' calls take a pointer to an RB node or RB root. They do not change the pointed objects, so add a 'const' qualifier in order to make life of the users of these functions easier. Indeed, if I have my own constant pointer &const struct my_type *p, and I call 'rb_next(&p->rb)', I get a GCC warning: warning: passing argument 1 of ‘rb_next’ discards qualifiers from pointer target type Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse Signed-off-by: Linus Torvalds --- lib/rbtree.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'lib') diff --git a/lib/rbtree.c b/lib/rbtree.c index 48499c2d88cc..9956b99649f0 100644 --- a/lib/rbtree.c +++ b/lib/rbtree.c @@ -292,7 +292,7 @@ EXPORT_SYMBOL(rb_erase); /* * This function returns the first node (in sort order) of the tree. */ -struct rb_node *rb_first(struct rb_root *root) +struct rb_node *rb_first(const struct rb_root *root) { struct rb_node *n; @@ -305,7 +305,7 @@ struct rb_node *rb_first(struct rb_root *root) } EXPORT_SYMBOL(rb_first); -struct rb_node *rb_last(struct rb_root *root) +struct rb_node *rb_last(const struct rb_root *root) { struct rb_node *n; @@ -318,7 +318,7 @@ struct rb_node *rb_last(struct rb_root *root) } EXPORT_SYMBOL(rb_last); -struct rb_node *rb_next(struct rb_node *node) +struct rb_node *rb_next(const struct rb_node *node) { struct rb_node *parent; @@ -331,7 +331,7 @@ struct rb_node *rb_next(struct rb_node *node) node = node->rb_right; while (node->rb_left) node=node->rb_left; - return node; + return (struct rb_node *)node; } /* No right-hand children. Everything down and left is @@ -347,7 +347,7 @@ struct rb_node *rb_next(struct rb_node *node) } EXPORT_SYMBOL(rb_next); -struct rb_node *rb_prev(struct rb_node *node) +struct rb_node *rb_prev(const struct rb_node *node) { struct rb_node *parent; @@ -360,7 +360,7 @@ struct rb_node *rb_prev(struct rb_node *node) node = node->rb_left; while (node->rb_right) node=node->rb_right; - return node; + return (struct rb_node *)node; } /* No left-hand children. Go up till we find an ancestor which -- cgit v1.2.2