From 84a0bd5b2830722cf80ff6ad33ef98101a947e14 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 5 Aug 2010 09:22:19 -0500 Subject: [PATCH] gdbstub: Optimize kgdb's "thread:" response for the gdb serial protocol The gdb debugger understands how to parse short versions of the thread reference string as long as the bytes are paired in sets of two characters. The kgdb implementation was always sending 8 leading zeros which could be omitted, and further optimized in the case of non-negative thread numbers. The negative numbers are used to reference a specific cpu in the case of kgdb. An example of the previous i386 stop packet looks like: T05thread:00000000000003bb; New stop packet response: T05thread:03bb; The previous ThreadInfo response looks like: m00000000fffffffe,0000000000000001,0000000000000002,0000000000000003,0000000000000004,0000000000000005,0000000000000006,0000000000000007,000000000000000c,0000000000000088,000000000000008a,000000000000008b,000000000000008c,000000000000008d,000000000000008e,00000000000000d4,00000000000000d5,00000000000000dd New ThreadInfo response: mfffffffe,01,02,03,04,05,06,07,0c,88,8a,8b,8c,8d,8e,d4,d5,dd A few bytes saved means better response time when using kgdb over a serial line. Signed-off-by: Jason Wessel --- Reading git-format-patch failed