Messages in this thread Patch in this message | | | Date | Sun, 5 Jun 2011 18:40:38 -0600 | From | Jean Sacren <> | Subject | [PATCH 1/1] boot: Enhance performance by eliminating unnecessary calls to printf() |
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Hi,
Repeated calling to printf() for 13 times is a dire waste of CPU cycles. For performance, combine all those calls into one while source code formatting is preserved for readability.
Compile tested only.
Signed-off-by: Jean Sacren <sakiwit@gmail.com> --- arch/x86/boot/compressed/mkpiggy.c | 30 ++++++++++++++++-------------- 1 files changed, 16 insertions(+), 14 deletions(-)
diff --git a/arch/x86/boot/compressed/mkpiggy.c b/arch/x86/boot/compressed/mkpiggy.c index 46a8238..0b6d82c 100644 --- a/arch/x86/boot/compressed/mkpiggy.c +++ b/arch/x86/boot/compressed/mkpiggy.c @@ -44,6 +44,7 @@ int main(int argc, char *argv[]) long ilen; unsigned long offs; FILE *f; + char *msg; if (argc < 2) { fprintf(stderr, "Usage: %s compressed_file\n", argv[0]); @@ -82,21 +83,22 @@ int main(int argc, char *argv[]) offs += 64*1024 + 128; /* Add 64K + 128 bytes slack */ offs = (offs+4095) & ~4095; /* Round to a 4K boundary */ - printf(".section \".rodata..compressed\",\"a\",@progbits\n"); - printf(".globl z_input_len\n"); - printf("z_input_len = %lu\n", ilen); - printf(".globl z_output_len\n"); - printf("z_output_len = %lu\n", (unsigned long)olen); - printf(".globl z_extract_offset\n"); - printf("z_extract_offset = 0x%lx\n", offs); /* z_extract_offset_negative allows simplification of head_32.S */ - printf(".globl z_extract_offset_negative\n"); - printf("z_extract_offset_negative = -0x%lx\n", offs); - - printf(".globl input_data, input_data_end\n"); - printf("input_data:\n"); - printf(".incbin \"%s\"\n", argv[1]); - printf("input_data_end:\n"); + msg = ".section \".rodata..compressed\",\"a\",@progbits\n" + ".globl z_input_len\n" + "z_input_len = %lu\n" + ".globl z_output_len\n" + "z_output_len = %lu\n" + ".globl z_extract_offset\n" + "z_extract_offset = 0x%lx\n" + ".globl z_extract_offset_negative\n" + "z_extract_offset_negative = -0x%lx\n" + ".globl input_data, input_data_end\n" + "input_data:\n" + ".incbin \"%s\"\n" + "input_data_end:\n"; + + printf(msg, ilen, (unsigned long)olen, offs, offs, argv[1]); return 0; } -- 1.7.2.2
-- Jean Sacren
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