linux-toradex.git/arch/parisc/kernel/unwind.c, branch v3.4.2 Linux kernel for Apalis and Colibri modules parisc: unwind - optimise linked-list searches for modules 2010-10-22T01:12:19+00:00 Phil Carmody ext-phil.2.carmody@nokia.com 2010-09-10T10:47:59+00:00 b1b1d4a6f244eb9513f006a188f7ed30d5014de5 Having many dozens of modules, the searches down the linked list of sections would dominate the lookup time, dwarfing any savings from the binary search within the section. A simple move-to-front optimisation exploits the commonality of the code paths taken, and in simple real-world tests on other architectures reduced the number of steps in the search to barely more than 1. Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com> Signed-off-by: Kyle McMartin <kyle@redhat.com> 
Having many dozens of modules, the searches down the linked
list of sections would dominate the lookup time, dwarfing
any savings from the binary search within the section.

A simple move-to-front optimisation exploits the commonality
of the code paths taken, and in simple real-world tests
on other architectures reduced the number of steps in the
search to barely more than 1.

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Kyle McMartin <kyle@redhat.com>
parisc: use sort() instead of home-made implementation (v2) 2009-12-16T03:48:55+00:00 Helge Deller deller@gmx.de 2009-11-06T23:07:42+00:00 8f78df872d463ac43315916663b3e688ebb2422f Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Randolph Chung <tausq@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca> 
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Randolph Chung <tausq@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
parisc: add CALLER_ADDR{0-6} macros 2009-12-16T03:48:54+00:00 Helge Deller deller@gmx.de 2009-10-25T21:48:36+00:00 11e178091f6a9c5ca479f8a276b9dd0dfacf8fc4 Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca> 
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
parisc: fix unwind with recent gcc versions 2009-11-30T16:20:24+00:00 Helge Deller deller@gmx.de 2009-11-28T20:33:11+00:00 33a932d14323b957a4e17a6c8428d3f048a30822 kernel unwinding is broken with gcc >= 4.x. Part of the problem is that binutils seems very sensitive to where the unwind information is stored. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
kernel unwinding is broken with gcc >= 4.x.  Part of the problem is that
binutils seems very sensitive to where the unwind information is stored.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parisc: fix GFP_KERNEL use while atomic in unwinder 2009-01-05T18:15:25+00:00 Helge Deller deller@gmx.de 2008-12-17T22:57:34+00:00 e0e7ed4811ce32d48ca8ee9fd136357d093243a9 Since unwind_frame_init_from_blocked_task() may be called from interrupt/in_atomic context, it needs to kmalloc() memory with GFP_ATOMIC instead of GFP_KERNEL. This fixes this warning (ShowTasks called from sysrq handler): BUG: sleeping function called from invalid context at mm/slab.c:3044 in_atomic(): 1, irqs_disabled(): 1, pid: 2119, name: miniruby Backtrace: [<10132e78>] __might_sleep+0x4c/0x118 [<1018f644>] kmem_cache_alloc+0x2c/0xb4 [<1011bae0>] unwind_frame_init_from_blocked_task+0x30/0xa0 [<1010fd3c>] parisc_show_stack+0x3c/0xac [<10132c7c>] show_state_filter+0x80/0xd8 [<102f4074>] __handle_sysrq+0xd0/0x1b0 [<102f9558>] receive_chars+0x22c/0x318 [<102f9940>] serial8250_handle_port+0x40/0x88 [<102f9a8c>] serial8250_interrupt+0x104/0x10c [<10161920>] handle_IRQ_event+0x44/0x94 [<10161acc>] __do_IRQ+0x15c/0x1dc [<102c442c>] superio_interrupt+0x74/0xa8 [<10161920>] handle_IRQ_event+0x44/0x94 [<10161acc>] __do_IRQ+0x15c/0x1dc [<10110fb4>] do_cpu_irq_mask+0x90/0xbc [<10114068>] intr_return+0x0/0x4 Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca> 
Since unwind_frame_init_from_blocked_task() may be called from
interrupt/in_atomic context, it needs to kmalloc() memory with
GFP_ATOMIC instead of GFP_KERNEL.

This fixes this warning (ShowTasks called from sysrq handler):

BUG: sleeping function called from invalid context at mm/slab.c:3044
in_atomic(): 1, irqs_disabled(): 1, pid: 2119, name: miniruby
Backtrace:
 [<10132e78>] __might_sleep+0x4c/0x118
 [<1018f644>] kmem_cache_alloc+0x2c/0xb4
 [<1011bae0>] unwind_frame_init_from_blocked_task+0x30/0xa0
 [<1010fd3c>] parisc_show_stack+0x3c/0xac
 [<10132c7c>] show_state_filter+0x80/0xd8
 [<102f4074>] __handle_sysrq+0xd0/0x1b0
 [<102f9558>] receive_chars+0x22c/0x318
 [<102f9940>] serial8250_handle_port+0x40/0x88
 [<102f9a8c>] serial8250_interrupt+0x104/0x10c
 [<10161920>] handle_IRQ_event+0x44/0x94
 [<10161acc>] __do_IRQ+0x15c/0x1dc
 [<102c442c>] superio_interrupt+0x74/0xa8
 [<10161920>] handle_IRQ_event+0x44/0x94
 [<10161acc>] __do_IRQ+0x15c/0x1dc
 [<10110fb4>] do_cpu_irq_mask+0x90/0xbc
 [<10114068>] intr_return+0x0/0x4

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
parisc: initialize unwinder much earlier 2008-10-10T16:32:30+00:00 James Bottomley James.Bottomley@HansenPartnership.com 2008-09-11T14:17:23+00:00 f0514ae323f19ba1ad4bea4174ea274c812f7eee The unwinder was being initialized way too late to be any use debugging early boot crashes. Instead of relying on module_init initcalls to initialize it, let's do it explicitly as early as we can. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca> 
The unwinder was being initialized way too late to be any use
debugging early boot crashes. Instead of relying on module_init
initcalls to initialize it, let's do it explicitly as early as
we can.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
[PARISC] Kill incorrect cast warning in unwinder 2007-10-18T07:59:04+00:00 Kyle McMartin kyle@mcmartin.ca 2007-10-18T07:03:56+00:00 7819994312fd4c3c04456abb6a64c810ecde3db4 Signed-off-by: Kyle McMartin <kyle@mcmartin.ca> 
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
kallsyms: make KSYM_NAME_LEN include space for trailing '\0' 2007-07-17T17:23:03+00:00 Tejun Heo htejun@gmail.com 2007-07-17T11:03:51+00:00 9281acea6a3687ff0f262e0be31eac34895b95d7 KSYM_NAME_LEN is peculiar in that it does not include the space for the trailing '\0', forcing all users to use KSYM_NAME_LEN + 1 when allocating buffer. This is nonsense and error-prone. Moreover, when the caller forgets that it's very likely to subtly bite back by corrupting the stack because the last position of the buffer is always cleared to zero. This patch increments KSYM_NAME_LEN by one and updates code accordingly. * off-by-one bug in asm-powerpc/kprobes.h::kprobe_lookup_name() macro is fixed. * Where MODULE_NAME_LEN and KSYM_NAME_LEN were used together, MODULE_NAME_LEN was treated as if it didn't include space for the trailing '\0'. Fix it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Paulo Marques <pmarques@grupopie.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
KSYM_NAME_LEN is peculiar in that it does not include the space for the
trailing '\0', forcing all users to use KSYM_NAME_LEN + 1 when allocating
buffer.  This is nonsense and error-prone.  Moreover, when the caller
forgets that it's very likely to subtly bite back by corrupting the stack
because the last position of the buffer is always cleared to zero.

This patch increments KSYM_NAME_LEN by one and updates code accordingly.

* off-by-one bug in asm-powerpc/kprobes.h::kprobe_lookup_name() macro
  is fixed.

* Where MODULE_NAME_LEN and KSYM_NAME_LEN were used together,
  MODULE_NAME_LEN was treated as if it didn't include space for the
  trailing '\0'.  Fix it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Paulo Marques <pmarques@grupopie.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[PARISC] unwinder improvements 2007-06-21T21:46:22+00:00 Randolph Chung tausq@debian.org 2007-06-12T06:27:32+00:00 05dc16d6a175139a5872d08db56ee277ec90df5b Add special-case handling for "handle_interruption" so that we can rewind past the interruption. This is useful for seeing what caused a BUG() or WARN_ON(); otherwise the unwind stops at the interruption. Signed-off-by: Randolph Chung <tausq@debian.org> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org> 
Add special-case handling for "handle_interruption" so that we can rewind
past the interruption. This is useful for seeing what caused a BUG() or
WARN_ON(); otherwise the unwind stops at the interruption.

Signed-off-by: Randolph Chung <tausq@debian.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
[PARISC] Fix unwinder on 64-bit kernels 2007-06-21T21:46:21+00:00 Randolph Chung tausq@debian.org 2007-06-12T06:27:32+00:00 e036306aa1832963cd147849b282259a32f5ac08 The unwinder was broken by the shift of PAGE_OFFSET in order to increase the size of the vmalloc area on 64-bit kernels. Signed-off-by: Randolph Chung <tausq@debian.org> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org> 
The unwinder was broken by the shift of PAGE_OFFSET in order to increase the
size of the vmalloc area on 64-bit kernels.

Signed-off-by: Randolph Chung <tausq@debian.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>