From 39d997b514e12d5aff0dca206eb8996b3957927e Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Mon, 21 Dec 2009 16:20:16 -0800 Subject: x86, core: Optimize hweight32() Optimize hweight32 by using the same technique in hweight64. The proof of this technique can be found in the commit log for f9b4192923fa6e38331e88214b1fe5fc21583fcc ("bitops: hweight() speedup"). The userspace benchmark on x86_32 showed 20% speedup with bitmap_weight() which uses hweight32 to count bits for each unsigned long on 32bit architectures. int main(void) { #define SZ (1024 * 1024 * 512) static DECLARE_BITMAP(bitmap, SZ) = { [0 ... 100] = 1, }; return bitmap_weight(bitmap, SZ); } Signed-off-by: Akinobu Mita Signed-off-by: Andrew Morton Cc: Linus Torvalds LKML-Reference: <1258603932-4590-1-git-send-email-akinobu.mita@gmail.com> [ only x86 sets ARCH_HAS_FAST_MULTIPLIER so we do this via the x86 tree] Signed-off-by: Ingo Molnar --- lib/hweight.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'lib') diff --git a/lib/hweight.c b/lib/hweight.c index 389424ecb129..63ee4eb1228d 100644 --- a/lib/hweight.c +++ b/lib/hweight.c @@ -11,11 +11,18 @@ unsigned int hweight32(unsigned int w) { +#ifdef ARCH_HAS_FAST_MULTIPLIER + w -= (w >> 1) & 0x55555555; + w = (w & 0x33333333) + ((w >> 2) & 0x33333333); + w = (w + (w >> 4)) & 0x0f0f0f0f; + return (w * 0x01010101) >> 24; +#else unsigned int res = w - ((w >> 1) & 0x55555555); res = (res & 0x33333333) + ((res >> 2) & 0x33333333); res = (res + (res >> 4)) & 0x0F0F0F0F; res = res + (res >> 8); return (res + (res >> 16)) & 0x000000FF; +#endif } EXPORT_SYMBOL(hweight32); -- cgit v1.2.3 From bc7259a2ce764ea16200eb9e53f6e136e918d065 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Thu, 7 Jan 2010 11:43:50 +0000 Subject: lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches Signed-off-by: David S. Miller --- lib/vsprintf.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/vsprintf.c b/lib/vsprintf.c index d4996cf46eb6..dc48d2b32ebd 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include /* for PAGE_SIZE */ @@ -681,11 +682,21 @@ static char *mac_address_string(char *buf, char *end, u8 *addr, char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; char *p = mac_addr; int i; + bool bitrev; + char separator; + + if (fmt[1] == 'F') { /* FDDI canonical format */ + bitrev = true; + separator = '-'; + } else { + bitrev = false; + separator = ':'; + } for (i = 0; i < 6; i++) { - p = pack_hex_byte(p, addr[i]); + p = pack_hex_byte(p, bitrev ? bitrev8(addr[i]) : addr[i]); if (fmt[0] == 'M' && i != 5) - *p++ = ':'; + *p++ = separator; } *p = '\0'; @@ -896,6 +907,10 @@ static char *uuid_string(char *buf, char *end, const u8 *addr, * - 'M' For a 6-byte MAC address, it prints the address in the * usual colon-separated hex notation * - 'm' For a 6-byte MAC address, it prints the hex address without colons + * - 'MF' For a 6-byte MAC FDDI address, it prints the address + * with a dash-separated hex notation with bit reversed bytes + * - 'mF' For a 6-byte MAC FDDI address, it prints the address + * in hex notation without separators with bit reversed bytes * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) * IPv6 uses colon separated network-order 16 bit hex with leading 0's @@ -939,6 +954,7 @@ static char *pointer(const char *fmt, char *buf, char *end, void *ptr, return resource_string(buf, end, ptr, spec, fmt); case 'M': /* Colon separated: 00:01:02:03:04:05 */ case 'm': /* Contiguous: 000102030405 */ + /* [mM]F (FDDI, bit reversed) */ return mac_address_string(buf, end, ptr, spec, fmt); case 'I': /* Formatted IP supported * 4: 1.2.3.4 -- cgit v1.2.3 From c8e000604bce02a87742240a9b716a0f1b680c0b Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Mon, 11 Jan 2010 00:44:14 -0800 Subject: lib: Kill bit-reversed FDDI MAC output case, it's bogus. Signed-off-by: Joe Perches Signed-off-by: David S. Miller --- lib/vsprintf.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) (limited to 'lib') diff --git a/lib/vsprintf.c b/lib/vsprintf.c index dc48d2b32ebd..e83e3e79a989 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -25,7 +25,6 @@ #include #include #include -#include #include #include /* for PAGE_SIZE */ @@ -682,19 +681,16 @@ static char *mac_address_string(char *buf, char *end, u8 *addr, char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; char *p = mac_addr; int i; - bool bitrev; char separator; if (fmt[1] == 'F') { /* FDDI canonical format */ - bitrev = true; separator = '-'; } else { - bitrev = false; separator = ':'; } for (i = 0; i < 6; i++) { - p = pack_hex_byte(p, bitrev ? bitrev8(addr[i]) : addr[i]); + p = pack_hex_byte(p, addr[i]); if (fmt[0] == 'M' && i != 5) *p++ = separator; } @@ -908,9 +904,7 @@ static char *uuid_string(char *buf, char *end, const u8 *addr, * usual colon-separated hex notation * - 'm' For a 6-byte MAC address, it prints the hex address without colons * - 'MF' For a 6-byte MAC FDDI address, it prints the address - * with a dash-separated hex notation with bit reversed bytes - * - 'mF' For a 6-byte MAC FDDI address, it prints the address - * in hex notation without separators with bit reversed bytes + * with a dash-separated hex notation * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) * IPv6 uses colon separated network-order 16 bit hex with leading 0's -- cgit v1.2.3 From 0159f24ee764927bf44c1a25473bd4517febd21c Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Wed, 13 Jan 2010 20:23:30 -0800 Subject: lib/vsprintf.c: Add IPV4 options %pI4[hnbl] for host, network, big and little endian This should allow the removal of the #defines and uses of NIPQUAD and NIPQUAD_FMT Signed-off-by: Joe Perches Signed-off-by: David S. Miller --- lib/vsprintf.c | 36 +++++++++++++++++++++++++++++++----- 1 file changed, 31 insertions(+), 5 deletions(-) (limited to 'lib') diff --git a/lib/vsprintf.c b/lib/vsprintf.c index e83e3e79a989..add0446dd921 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -699,13 +699,37 @@ static char *mac_address_string(char *buf, char *end, u8 *addr, return string(buf, end, mac_addr, spec); } -static char *ip4_string(char *p, const u8 *addr, bool leading_zeros) +static char *ip4_string(char *p, const u8 *addr, const char *fmt) { int i; - + bool leading_zeros = (fmt[0] == 'i'); + int index; + int step; + + switch (fmt[2]) { + case 'h': +#ifdef __BIG_ENDIAN + index = 0; + step = 1; +#else + index = 3; + step = -1; +#endif + break; + case 'l': + index = 3; + step = -1; + break; + case 'n': + case 'b': + default: + index = 0; + step = 1; + break; + } for (i = 0; i < 4; i++) { char temp[3]; /* hold each IP quad in reverse order */ - int digits = put_dec_trunc(temp, addr[i]) - temp; + int digits = put_dec_trunc(temp, addr[index]) - temp; if (leading_zeros) { if (digits < 3) *p++ = '0'; @@ -717,6 +741,7 @@ static char *ip4_string(char *p, const u8 *addr, bool leading_zeros) *p++ = temp[digits]; if (i < 3) *p++ = '.'; + index += step; } *p = '\0'; @@ -796,7 +821,7 @@ static char *ip6_compressed_string(char *p, const char *addr) if (useIPv4) { if (needcolon) *p++ = ':'; - p = ip4_string(p, &in6.s6_addr[12], false); + p = ip4_string(p, &in6.s6_addr[12], "I4"); } *p = '\0'; @@ -836,7 +861,7 @@ static char *ip4_addr_string(char *buf, char *end, const u8 *addr, { char ip4_addr[sizeof("255.255.255.255")]; - ip4_string(ip4_addr, addr, fmt[0] == 'i'); + ip4_string(ip4_addr, addr, fmt); return string(buf, end, ip4_addr, spec); } @@ -911,6 +936,7 @@ static char *uuid_string(char *buf, char *end, const u8 *addr, * - 'i' [46] for 'raw' IPv4/IPv6 addresses * IPv6 omits the colons (01020304...0f) * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) + * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order * - 'I6c' for IPv6 addresses printed as specified by * http://www.ietf.org/id/draft-kawamura-ipv6-text-representation-03.txt * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form -- cgit v1.2.3 From 4c54005ca438a8b46dd542b497d4f0dc2ca375e8 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 14 Jan 2010 16:10:57 -0800 Subject: rcu: 1Q2010 update for RCU documentation Add expedited functions. Review documentation and update obsolete verbiage. Also fix the advice for the RCU CPU-stall kernel configuration parameter, and document RCU CPU-stall warnings. Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <12635142581866-git-send-email-> Signed-off-by: Ingo Molnar --- lib/Kconfig.debug | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 25c3ed594c54..6bf97d176326 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -765,9 +765,9 @@ config RCU_CPU_STALL_DETECTOR CPUs are delaying the current grace period, but only when the grace period extends for excessive time periods. - Say Y if you want RCU to perform such checks. + Say N if you want to disable such checks. - Say N if you are unsure. + Say Y if you are unsure. config KPROBES_SANITY_TEST bool "Kprobes sanity tests" -- cgit v1.2.3 From 660e2acad81c19b404f7d7d06e57a6d5e6ce7426 Mon Sep 17 00:00:00 2001 From: Chris Smith Date: Wed, 27 Jan 2010 22:03:11 +0900 Subject: sh: kmemleak support. Enables support for kmemleak on sh. Signed-off-by: Chris Smith Signed-off-by: Paul Mundt --- lib/Kconfig.debug | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 25c3ed594c54..d62e3cdab357 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -355,7 +355,7 @@ config SLUB_STATS config DEBUG_KMEMLEAK bool "Kernel memory leak detector" depends on DEBUG_KERNEL && EXPERIMENTAL && !MEMORY_HOTPLUG && \ - (X86 || ARM || PPC || S390) + (X86 || ARM || PPC || S390 || SUPERH) select DEBUG_FS if SYSFS select STACKTRACE if STACKTRACE_SUPPORT -- cgit v1.2.3 From 24551f64d47af9539a7f324343bffeea09d9dcfa Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 12 Jan 2010 21:25:24 +0000 Subject: lmb: Add lmb_free() We can free memory allocated with lmb_alloc() by removing it from the list of reserved LMBs. Rework lmb_remove() to allow that possibility and add lmb_free() which exploits it. BenH: Removed some useless parenthesis Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt --- lib/lmb.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/lmb.c b/lib/lmb.c index 9cee17142b2c..b1fc52606524 100644 --- a/lib/lmb.c +++ b/lib/lmb.c @@ -205,9 +205,8 @@ long lmb_add(u64 base, u64 size) } -long lmb_remove(u64 base, u64 size) +static long __lmb_remove(struct lmb_region *rgn, u64 base, u64 size) { - struct lmb_region *rgn = &(lmb.memory); u64 rgnbegin, rgnend; u64 end = base + size; int i; @@ -254,6 +253,16 @@ long lmb_remove(u64 base, u64 size) return lmb_add_region(rgn, end, rgnend - end); } +long lmb_remove(u64 base, u64 size) +{ + return __lmb_remove(&lmb.memory, base, size); +} + +long __init lmb_free(u64 base, u64 size) +{ + return __lmb_remove(&lmb.reserved, base, size); +} + long __init lmb_reserve(u64 base, u64 size) { struct lmb_region *_rgn = &lmb.reserved; -- cgit v1.2.3 From 632ee200130899252508c478ad0e808222573fbc Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 22 Feb 2010 17:04:45 -0800 Subject: rcu: Introduce lockdep-based checking to RCU read-side primitives Inspection is proving insufficient to catch all RCU misuses, which is understandable given that rcu_dereference() might be protected by any of four different flavors of RCU (RCU, RCU-bh, RCU-sched, and SRCU), and might also/instead be protected by any of a number of locking primitives. It is therefore time to enlist the aid of lockdep. This set of patches is inspired by earlier work by Peter Zijlstra and Thomas Gleixner, and takes the following approach: o Set up separate lockdep classes for RCU, RCU-bh, and RCU-sched. o Set up separate lockdep classes for each instance of SRCU. o Create primitives that check for being in an RCU read-side critical section. These return exact answers if lockdep is fully enabled, but if unsure, report being in an RCU read-side critical section. (We want to avoid false positives!) The primitives are: For RCU: rcu_read_lock_held(void) For RCU-bh: rcu_read_lock_bh_held(void) For RCU-sched: rcu_read_lock_sched_held(void) For SRCU: srcu_read_lock_held(struct srcu_struct *sp) o Add rcu_dereference_check(), which takes a second argument in which one places a boolean expression based on the above primitives and/or lockdep_is_held(). o A new kernel configuration parameter, CONFIG_PROVE_RCU, enables rcu_dereference_check(). This depends on CONFIG_PROVE_LOCKING, and should be quite helpful during the transition period while CONFIG_PROVE_RCU-unaware patches are in flight. The existing rcu_dereference() primitive does no checking, but upcoming patches will change that. Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-1-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar --- lib/Kconfig.debug | 12 ++++++++++++ lib/debug_locks.c | 1 + 2 files changed, 13 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 6bf97d176326..6af20a8a0a54 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -499,6 +499,18 @@ config PROVE_LOCKING For more details, see Documentation/lockdep-design.txt. +config PROVE_RCU + bool "RCU debugging: prove RCU correctness" + depends on PROVE_LOCKING + default n + help + This feature enables lockdep extensions that check for correct + use of RCU APIs. This is currently under development. Say Y + if you want to debug RCU usage or help work on the PROVE_RCU + feature. + + Say N if you are unsure. + config LOCKDEP bool depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT diff --git a/lib/debug_locks.c b/lib/debug_locks.c index bc3b11731b9c..5bf0020b9248 100644 --- a/lib/debug_locks.c +++ b/lib/debug_locks.c @@ -23,6 +23,7 @@ * shut up after that. */ int debug_locks = 1; +EXPORT_SYMBOL_GPL(debug_locks); /* * The locking-testsuite uses to get a -- cgit v1.2.3 From 2676a58c980b7ef076cc9bbff3fd8c9d2d5417ea Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 22 Feb 2010 17:04:54 -0800 Subject: radix-tree: Disable RCU lockdep checking in radix tree Because the radix tree is used with many different locking designs, we cannot do any effective checking without changing the radix-tree APIs. It might make sense to do this later, but only if the RCU lockdep checking proves itself sufficiently valuable. Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-10-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar --- lib/radix-tree.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'lib') diff --git a/lib/radix-tree.c b/lib/radix-tree.c index 92cdd9936e3d..6b9670d6bbf9 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -364,7 +364,7 @@ static void *radix_tree_lookup_element(struct radix_tree_root *root, unsigned int height, shift; struct radix_tree_node *node, **slot; - node = rcu_dereference(root->rnode); + node = rcu_dereference_raw(root->rnode); if (node == NULL) return NULL; @@ -384,7 +384,7 @@ static void *radix_tree_lookup_element(struct radix_tree_root *root, do { slot = (struct radix_tree_node **) (node->slots + ((index>>shift) & RADIX_TREE_MAP_MASK)); - node = rcu_dereference(*slot); + node = rcu_dereference_raw(*slot); if (node == NULL) return NULL; @@ -568,7 +568,7 @@ int radix_tree_tag_get(struct radix_tree_root *root, if (!root_tag_get(root, tag)) return 0; - node = rcu_dereference(root->rnode); + node = rcu_dereference_raw(root->rnode); if (node == NULL) return 0; @@ -602,7 +602,7 @@ int radix_tree_tag_get(struct radix_tree_root *root, BUG_ON(ret && saw_unset_tag); return !!ret; } - node = rcu_dereference(node->slots[offset]); + node = rcu_dereference_raw(node->slots[offset]); shift -= RADIX_TREE_MAP_SHIFT; height--; } @@ -711,7 +711,7 @@ __lookup(struct radix_tree_node *slot, void ***results, unsigned long index, } shift -= RADIX_TREE_MAP_SHIFT; - slot = rcu_dereference(slot->slots[i]); + slot = rcu_dereference_raw(slot->slots[i]); if (slot == NULL) goto out; } @@ -758,7 +758,7 @@ radix_tree_gang_lookup(struct radix_tree_root *root, void **results, unsigned long cur_index = first_index; unsigned int ret; - node = rcu_dereference(root->rnode); + node = rcu_dereference_raw(root->rnode); if (!node) return 0; @@ -787,7 +787,7 @@ radix_tree_gang_lookup(struct radix_tree_root *root, void **results, slot = *(((void ***)results)[ret + i]); if (!slot) continue; - results[ret + nr_found] = rcu_dereference(slot); + results[ret + nr_found] = rcu_dereference_raw(slot); nr_found++; } ret += nr_found; @@ -826,7 +826,7 @@ radix_tree_gang_lookup_slot(struct radix_tree_root *root, void ***results, unsigned long cur_index = first_index; unsigned int ret; - node = rcu_dereference(root->rnode); + node = rcu_dereference_raw(root->rnode); if (!node) return 0; @@ -915,7 +915,7 @@ __lookup_tag(struct radix_tree_node *slot, void ***results, unsigned long index, } } shift -= RADIX_TREE_MAP_SHIFT; - slot = rcu_dereference(slot->slots[i]); + slot = rcu_dereference_raw(slot->slots[i]); if (slot == NULL) break; } @@ -951,7 +951,7 @@ radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results, if (!root_tag_get(root, tag)) return 0; - node = rcu_dereference(root->rnode); + node = rcu_dereference_raw(root->rnode); if (!node) return 0; @@ -980,7 +980,7 @@ radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results, slot = *(((void ***)results)[ret + i]); if (!slot) continue; - results[ret + nr_found] = rcu_dereference(slot); + results[ret + nr_found] = rcu_dereference_raw(slot); nr_found++; } ret += nr_found; @@ -1020,7 +1020,7 @@ radix_tree_gang_lookup_tag_slot(struct radix_tree_root *root, void ***results, if (!root_tag_get(root, tag)) return 0; - node = rcu_dereference(root->rnode); + node = rcu_dereference_raw(root->rnode); if (!node) return 0; -- cgit v1.2.3 From 96be753af91fc9d582450a84722f6a6721d218ad Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 22 Feb 2010 17:04:55 -0800 Subject: idr: Apply lockdep-based diagnostics to rcu_dereference() uses Because idr can be used with any of a number of locks or with any flavor of RCU, just disable the lockdep-based diagnostics. If idr needs diagnostics, the check expression will need to be passed into the relevant idr primitives as an additional argument. Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-11-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar --- lib/idr.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'lib') diff --git a/lib/idr.c b/lib/idr.c index 0dc782216d4b..2eb1dca03681 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -504,7 +504,7 @@ void *idr_find(struct idr *idp, int id) int n; struct idr_layer *p; - p = rcu_dereference(idp->top); + p = rcu_dereference_raw(idp->top); if (!p) return NULL; n = (p->layer+1) * IDR_BITS; @@ -519,7 +519,7 @@ void *idr_find(struct idr *idp, int id) while (n > 0 && p) { n -= IDR_BITS; BUG_ON(n != p->layer*IDR_BITS); - p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]); + p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]); } return((void *)p); } @@ -552,7 +552,7 @@ int idr_for_each(struct idr *idp, struct idr_layer **paa = &pa[0]; n = idp->layers * IDR_BITS; - p = rcu_dereference(idp->top); + p = rcu_dereference_raw(idp->top); max = 1 << n; id = 0; @@ -560,7 +560,7 @@ int idr_for_each(struct idr *idp, while (n > 0 && p) { n -= IDR_BITS; *paa++ = p; - p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]); + p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]); } if (p) { -- cgit v1.2.3 From 1ed509a225008c9e8c0644fbd22168e09a7383a0 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 22 Feb 2010 17:05:05 -0800 Subject: rcu: Add RCU_CPU_STALL_VERBOSE to dump detailed per-task information When RCU detects a grace-period stall, it currently just prints out the PID of any tasks doing the stalling. This patch adds RCU_CPU_STALL_VERBOSE, which enables the more-verbose reporting from sched_show_task(). Suggested-by: Thomas Gleixner Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-21-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar --- lib/Kconfig.debug | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 6af20a8a0a54..4cdab452bfe2 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -781,6 +781,18 @@ config RCU_CPU_STALL_DETECTOR Say Y if you are unsure. +config RCU_CPU_STALL_VERBOSE + bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR" + depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_RCU + default n + help + This option causes RCU to printk detailed per-task information + for any tasks that are stalling the current RCU grace period. + + Say N if you are unsure. + + Say Y if you want to enable such checks. + config KPROBES_SANITY_TEST bool "Kprobes sanity tests" depends on DEBUG_KERNEL -- cgit v1.2.3